Download Hi-Res ImageDownload to MS-PowerPointCite This:Ind. Eng. Chem. Res. 2019, 58, 27, 12149-12158

ArticleJune 10, 2019

Pilot-Scale Polyhydroxyalkanoate Production from Combined Treatment of Organic Fraction of Municipal Solid Waste and Sewage Sludge
Click to copy article linkArticle link copied!

Francesco Valentino*
Francesco Valentino
Department of Chemistry, “La Sapienza” University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
*E-mail: [email protected]
More by Francesco Valentino
http://orcid.org/0000-0003-2016-4347
Giulia Moretto
Giulia Moretto
Department of Environmental Science, Informatics and Statistics, Via Torino 155, 30170 Venezia Mestre, Italy
More by Giulia Moretto
Laura Lorini
Laura Lorini
Department of Chemistry, “La Sapienza” University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
More by Laura Lorini
David Bolzonella
David Bolzonella
Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
More by David Bolzonella
Paolo Pavan
Paolo Pavan
Department of Environmental Science, Informatics and Statistics, Via Torino 155, 30170 Venezia Mestre, Italy
More by Paolo Pavan
Mauro Majone
Mauro Majone
Department of Chemistry, “La Sapienza” University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
More by Mauro Majone

Open PDF

Industrial & Engineering Chemistry Research

Cite this: Ind. Eng. Chem. Res. 2019, 58, 27, 12149–12158

Click to copy citationCitation copied!

https://doi.org/10.1021/acs.iecr.9b01831

Published June 10, 2019

Request reuse permissions

Abstract

Click to copy section linkSection link copied!

Although the organic fraction of municipal solid waste (OFMSW) and sewage sludge (SS) originate from the same urban area and contain similar organic matter, they are collected separately and handled with different technologies. In this work, a combined treatment of OFMSW–SS mixture was investigated at pilot scale, by using a three-step mixed microbial culture (MMC) process in order to produce polyhydroxyalkanoate (PHA) as final high value biobased product. Biomass selection efficiency was quantified by PHA-specific storage rate that was 258 mg COD_PHA/g COD_Xa/h under the optimized process condition. In fed-batch tests, PHA-storing MMC was able to accumulate up to 46 wt % PHA. In the perspective of a full-scale application and taking into account the mass flows in each process step, an overall yield of 65 g PHA/kg TVS was estimated.

1. Introduction

Click to copy section linkSection link copied!

In the frame of applied microbiology and bioprocess engineering, the use of mixed microbial cultures (MMCs) is attracting remarkable attention for the development of novel bioprocesses that respond to changing environmental frameworks. A well-established example of MMC application consists of the production of a particular family of polyester, namely, polyhydroxyalkanoates (PHA). These biopolymers are synthesized as intracellular carbon and energy source mainly by numerous species of Gram-positive and/or Gram-negative microorganisms but also by anaerobic photosynthetic bacteria and Archea. (1) Since they are completely biodegradable and have thermoplastic properties, the interest in these biopolymers is progressively increasing, also in consideration of the possibility to use renewable resources (instead of fossil fuels) as carbon source for their synthesis. (2,3)

However, more investments are necessary to promote feasibility studies, possibly at a pilot-scale level, in order to quantify a reasonable range of PHA productivity and final polymer quality. These are crucial aspects for MMC derived PHA commercialization and relative market scenario, which presently does not exist yet. (4)

Nowadays, industrial-scale PHA production focuses on pure-culture systems, which are based on refine feedstock and sterile cultivation conditions. Both features entail a high-energy requirement that strongly increases the PHA production cost. (5) This is why the PHA production from microorganisms’ cultivation accounts for only a small percentage of global plastic production so far.

The possibility to integrate MMC–PHA production into infrastructures typically adopted for biowaste residuals and wastewater treatment could make this technology economically and environmentally sustainable. In the past decade, this basic concept has led to the scaling-up of the process from laboratory- to pilot-scale facilities with demonstrative plants. (2) The examples that have been reported in the literature show the integration of MMC–PHA production with municipal wastewater treatment, (6,7) excess sludge fermentation liquid, (8) and dairy and food-processing wastewater. (9,10)

Independent from the possible configurations, consistently explained in recent reviews, (2,4) MMC technology provides for the use of activated sludge as inoculum, the microbial composition of which needs to be enriched in bacteria with high polymer accumulation capacity. This approach is known as “feast–famine” selection strategy and is realized by applying dynamic feeding to microorganisms in sequencing reactors. (11) Under these process conditions, the microorganisms are submitted to consecutive periods of external substrate excess and lack. Those species able to store the substrate in the form of PHA during the feast phase have a competitive advantage over the others, because they can use the stored polymer as an intracellular carbon source when the substrate is no more available (famine phase). Fermented waste feedstock rich in volatile fatty acid (VFA) are usually the election substrates for this purpose.

Since our food supply chain has recently been recognized as being inefficient, producing large quantities of waste, (12) the need to both avoid waste production and find new renewable resources has led to the use of food waste as a renewable feedstock. Food waste includes the organic waste produced at household level or by the food service sector, and the waste produced at retail level. This source can be valorised with available practises and technologies (including composting, landfilling, anaerobic digestion, bioenergy production). In addition, the interest for biopolymer production from urban organic waste is relatively recent. In fact, few studies described different methods for PHA production from the organic fraction of municipal solid waste (OFMSW), (13) and related sources such as leachate, (14) percolate, (15) mixture of OFMSW, and primary sludge (PS). (16) In the context of a possible integration in the existing wastewater treatment plant (WWTP), pilot-scale demonstrations are of primary importance.

The study proposed herein describes PHA production by MMC using pretreated OFMSW and excess thickened secondary sludge (SS), applying the feast–famine approach in the traditional three-step process scheme, developed at pilot scale. The paper is focused on the treatment of these two relevant organic urban wastes since they have the same origin but are still separately collected and handled with different technologies. In this work, a single process technology has been proposed for the simultaneous treatment of both streams, collected in Treviso (northeast of Italy) municipality and presently valorized in a full-scale anaerobic digestion plant. If compared to the conventional anaerobic digestion technology, then PHA biobased products can offer a more profitable way to recover the organic matter, with the concrete option of retrofitting existing facilities of waste or wastewater treatment. The piloting facilities for PHA production from organic urban biowaste are located in the Treviso municipal WWTP.

2. Materials and Methods

Click to copy section linkSection link copied!

2.1. Pilot Plant Experimental Platform

A process schematic of the units installed at the Treviso WWTP is presented in Figure 1. A fermentation reactor produced a hydrolyzed and fermented OFMSW–SS mixture rich in VFA. The fermented feedstock was subjected to a first solid/liquid separation unit (C) for suspended solid removal before feeding in the first aerobic reactor (sequencing batch reactor, SBR). The SBR stimulated the storage response of initial activated sludge (inoculum), selecting a PHA-accumulating consortium. This selection was performed by applying a dynamic feeding condition, also known as feast-famine regime. (11) The second aerobic reactor (PHA production) produced PHA inside the harvested surplus biomass from SBR, when fed with VFA-rich stream after second solid/liquid separation unit (F).

Figure 1. Process scheme developed at pilot scale for OFMSW and SS valorization toward PHA production.

The start-up of the pilot units was realized in close times: acidogenic fermenter was started up in January 2017, and the SBR commenced biomass production from the end of March 2017. The first accumulation trials were made after pseudo steady state was achieved in the selection reactor. The operation of reactors is automated and controlled via a programmable logic controller (myRio Labview by National Instrument) except for the transfer of biomass from the selection/enrichment step to accumulation, and the treatment of VFA-rich stream in the second solid/liquid separation unit, which are manually operated/conducted.

2.1.1. Sewage Sludge (SS) and Organic Fraction of Municipal Solid Waste (OFMSW) Collection

The feedstock was collected weekly inside the Treviso municipal WWTP facility. The source-sorted collection of OFMSW was made throughout the whole Treviso municipality and transferred to the full-scale WWTP after its squeezing and homogenization in a dedicated plant. The squeezed OFMSW was then mixed with SS produced in the WWTP. The chemical features of the feedstock changed as a function of relative volume percentage of the substrates and mixed in two different ratios as it follows: OFMSW and SS at a volumetric fraction of 40–45% and 60–55%, respectively; OFMSW and SS at a volumetric fraction of 30–35% and 70–65%, respectively. Both mixtures were characterized in terms of total and volatile solids (TS and TVS), Total Kjeldahl nitrogen (TKN), and organic phosphorus (P), ammonium and phosphate, total and soluble chemical oxygen demand (COD_TOT, COD_SOL), and VFA. The main features of both mixtures are summarized in Table 1.

Table 1. Physical–Chemical Features of the Two Influent Mixtures of Urban Origin

	unfermented feedstock
parameter	OFMSW 40–45%/SS 60–55%^a	OFMSW 30–35%/SS 70–65%^a
TS (g/kg)	92 ± 5	56 ± 3
TVS (g/kg)	75 ± 4	44 ± 3
COD_TOT (g/L)	97 ± 8	62 ± 5
COD_SOL (g/L)	38 ± 2	20 ± 1
COD_VFA (g/L)	3.1 ± 0.9	2.5 ± 0.5
TKN (g N/kg TS)	24 ± 2	25 ± 3
phosphorus (P; g P/kg TS)	2.0 ± 0.1	2.3 ± 0.1
ammonia (N–NH₄⁺; mg/L)	327 ± 35	342 ± 28
phosphate (P–PO₄^3–; mg/L)	163 ± 6	113 ± 7

^{^a}

Each percentage refers to a volumetric fraction.

2.1.2. Pilot Units

The acidogenic fermentation unit included an anaerobic batch reactor (V = 380 L) and a filter-bag equipped centrifuge (unit “C”). The anaerobic reactor consisted of a continuous stirred tank reactor (CSTR), mechanically stirred and under temperature control by using a thermostatic jacket. The hydraulic retention time (HRT) was set at 6 days (equal to sludge retention time, SRT). The pH (5.0–5.5) was not controlled since the alkalinity of the feedstock ensured enough buffer capacity. A centrifugation unit was used for solids/liquid separation after fermentation: a coaxial centrifuge equipped with 5.0 μm porosity nylon filter bag for solids removal. This step was crucial for obtaining a cleaner filtered fermented stream (fFL), with a suspended solid level below 10.0 g/L, to be used for the following aerobic selection step after dilution with tap water.

Acidogenic fermentation has been conducted in continuous mode, by investigating different mixture composition and temperature (T); more specifically, different fermentation liquids (FL) were produced according to the following parameters: (FL-I) OFMSW 40–45% v/v, SS 55–60% v/v mixture, T 55 °C; (FL-II) OFMSW 30–35% v/v, SS 65–70% v/v mixture, T 55 °C; (FL-III) OFMSW 30–35% v/v, SS 65–70% v/v mixture, T 42 °C.

The three conditions have been tested without interruption of the fermentation process, by changing the OFMSW content first (from I to II) and then by changing the T from thermophilic (II) to mesophilic (III) conditions. The first trial tested condition I up to day 120, condition II from day 121 to 185, and condition III from day 185 to 255. The applied OLR was different between the three experimental conditions and strongly affected by the content of OFMSW in the feedstock: 12.2 ± 0.3 (condition I) and 6.6 ± 0.1 g TVS/L day (conditions II and III).

A SBR (working volume 120 L) was utilized for the PHA-accumulating biomass production. The SBR was inoculated with activated sludge from the Treviso full-scale WWTP. The aerobic run was conducted for approximately 7 months, at 1.0 day of HRT (equal to SRT) and a cycle length of 6 h. Each operating cycle was divided into four aerobic phases: biomass withdrawal (0.5 min), first aeration (10 min), feeding (0.5 min), and second aeration (349 min). The reactor was aerated by means of linear membrane blowers (Bibus EL-S-250), which allowed stirring the system. The temperature (22–25 °C, maintained with immersion heater) and pH (8.0–9.0) were continuously measured but not controlled. The applied OLR was set at 4.0 g COD_SOL/L day. In order to maintain such OLR, the fFLs were 6- to 10-fold diluted with tap water. Feedstock shifts were made at day 93 (from fFL-I to fFL-II) and day 160 (from fFL-II to fFL-III). The SBR performance was monitored by measurement of biomass concentration, as volatile suspended solid (VSS), PHA, and COD_SOL.

The accumulation potential of the biomass was exploited through fed-batch tests (V = 50–70 L), performed with both synthetic (acetic acid with no nutrient addition) and filtered fFL (ffFL; specifically ffFL-II and ffFL-III). The fFLs were further filtered with a stainless-steel filter press (unit “F”) equipped with 0.2 μm paper filter (CKP V28), in order to remove all the suspended solids and to obtain a clear feeding solution. The biomass (X) was loaded from the SBR at the end of the 6 h cycle and the initial ffFL/X ratio was chosen to be ≤2.0 COD basis, in order to prevent any possible substrate or pH inhibition phenomena. (17)

2.2. Sampling and Analytical Methods

Feedstock mixture was characterized after each collection (weekly basis). The analysis were performed on dry solid material at first, specifically for TS and TVS, COD, TKN, and P. COD_SOL, VFA, alkalinity, ammonium, and phosphate were measured on filtered (0.2 μm) samples. The same approach has been followed for fermented feedstock characterization even though with more frequent analysis (at least twice a week). In the aerobic reactors, the quantified parameters were total and volatile suspended solids (TSS and VSS), COD_SOL, ammonium, phosphate, VFA, and PHA. In the SBR, the mixed liquor was sampled at the end of the cycle (for COD_SOL, ammonium, phosphate, and PHA quantification) and at the end of the feast phase (for TSS, VSS, COD_SOL, and PHA quantification), according to a previous laboratory-scale study. (18) In the batch reactor, the mixed liquor was sampled at the beginning of each test and every hour (for VFA and PHA quantification). The COD_SOL and VSS were analyzed at the beginning and at the end of each test. All the analyses, except for VFA and PHA, were carried out in accordance with the standard methods. (19)

VFA were quantified using a gas chromatography (GC) method (Carlo Erba instruments) with hydrogen as gas carrier. The GC was equipped with a Fused Silica Capillary Column (Supelco Nukol TM, 15 m × 0.53 mm × 0.5 mm film thickness) and with a flame ionization detector (200 °C). During analysis, the temperature (T) increased from 80 to 200 °C with a rate of 10 °C/min.

For PHA measurements, 5.0 mL of unfiltered mixed liquor were treated with 1.0 mL of NaClO solution (5% active Cl₂) and then stored at −4 °C for following analysis. In accordance to Braunegg et al., (20) the polymer was extracted, hydrolyzed, and esterified to 3-hydroxyacyl methyl esters and quantified by GC method. The abundance of hydroxybutyric (HB) and hydroxyvaleric (HV) monomers were quantified using P(3HB-co-3HV) Sigma-Aldrich standard polymer at 5 wt % HV content.

2.3. Calculations

All the parameters characterizing reactor performances were calculated after steady states or pseudosteady state (for SBR) was achieved.

The fermentation process was considered under steady-state when a stable VFA distribution was observed, after 3.0 SRTs approximately (at day 20). Solubilization and fermentation yield (Y_VFA) were quantified with respect to the features of initial unfermented feedstock, in particular total COD (COD_TOT(0)) and TVS₍₀₎. COD_TOT was quantified as sum of separated COD analysis on dry matter and filtered liquid sample as explained in the above paragraph.

In the SBR, the pseudo steady state was recognized when the feast phase length remained approximately constant (within a 5% deviation from average) for at least 10 SRTs. (18) In each SBR cycle, the dissolved oxygen (DO) was continuously monitored in order to identify the period in which the readily biodegradable substrates (mainly VFA) were exhausted (end of feast phase), as indicated by a sudden increase of the O₂ concentration. The nonpolymer biomass (or active biomass, X_A) was calculated as the difference between VSS and PHA concentrations: X_A = VSS – PHA. The biomass PHA content (g PHA/g VSS) was defined as the ratio between the PHA and VSS concentrations. For rates and yields calculation, the mass values of X_A, PHA and VFA were converted into COD units by using the relative conversion factor from oxidation stoichiometry. (21) The specific VFA uptake rate was calculated as ratio between the removed VFA and the length of feast phase (t), per unit of X_A: (−qVFA^feast) = ΔVFA/(t·X_A). The specific COD_SOL removal rate was similarly calculated: (−qS^feast) = ΔCOD_SOL/(t·X_A). The PHA production rate was defined by the produced PHA divided by the feast phase length (t), per unit of X_A: qP^feast = ΔPHA/(t·X_A). The storage yields were defined by the ratio between the produced PHA and the consumed COD_SOL or VFA in the feast phase: Y_P/S^feast = ΔPHA/ΔCOD_SOL; Y_P/VFA^feast = ΔPHA/ΔVFA. The observed yield was calculated as it follows: Y_OBS^SBR = VSS/(OLR·HRT). In fed-batch accumulations, the specific PHA production rate (qP^batch) was calculated by linear regression of data versus time. Only the initial period (2.0 h from the beginning of each test) at constant rate was considered. The volumetric rate was transformed into specific rate using the X_A concentration at the beginning of the test. The growth yield was calculated as the ratio between the produced X_A and the removed VFA (Y_X/VFA^batch) or COD_SOL (Y_X/S^batch) at the end of each test. The storage yield was calculated as the ratio between the produced PHA and the removed VFA (Y_P/VFA^batch) or COD_SOL (Y_P/S^batch) at the end of the test. The final PHA content in the biomass was calculated at the end of each test as explained above.

3. Results and Discussion

Click to copy section linkSection link copied!

3.1. Fermentation of Feedstock for PHA Production

Acidogenic fermentation was feasible to good extent under each condition tested, even though some variations of performance were observed, particularly associated with the system stability.

Figure 2A shows the evolution of VFA production, COD_SOL, and pH from the process start-up; the three different periods at different feedstock composition and/or temperature are separated by vertical axis. Average data are reported in Table 2.

Figure 2. VFA, COD_SOL, and pH evolution in the fermented feedstock (A); VFA distribution under the three different conditions tested (B).

Table 2. Fermented Feedstock Characteristics and Related Fermentation Performances

parameter		FL-I	FL-II	FL-III
fermented feedstock characteristics
TS (g/kg)		82 ± 6	56 ± 4	57 ± 3
TVS (g/kg)		68 ± 4	46 ± 4	46 ± 2
COD_TOT (g/L)		98 ± 10	61 ± 8	60 ± 4
COD_SOL (g/L)		45 ± 8	32 ± 5	26 ± 3
COD_VFA (g/L)		23 ± 6	21 ± 3	19 ± 2
COD_VFA/COD_SOL		0.53 ± 0.11	0.64 ± 0.07	0.75 ± 0.09
alkalinity (mg CaCO₃/L)		5910 ± 469	4811 ± 741	4451 ± 498
TKN (g N/kg TS)		28 ± 4	23 ± 4	20 ± 2
phosphorus (P; g P/kg TS)		2.0 ± 0.3	2.2 ± 0.4	2.1 ± 0.3
ammonia (N–NH₄⁺; mg/L)		698 ± 55	724 ± 138	562 ± 44
phosphate (P–PO₄^3–; mg/L)		155 ± 28	127 ± 22	110 ± 9
COD_SOL/N/P		100/5.3/0.4	100/4.1/0.4	100/4.4/0.5
[C₃/(C₃+C₂)]_VFA (mol/mol)		0.15 ± 0.03	0.17 ± 0.02	0.16 ± 0.02
fermentation performance
solubilization	g COD_SOL/g COD_TOT(0)	0.08 ± 0.05	0.17 ± 0.02	0.10 ± 0.03
solubilization	g COD_SOL/g TVS₍₀₎	0.10 ± 0.06	0.26 ± 0.02	0.15 ± 0.03
yield (Y_VFA)	g COD_VFA/g COD_TOT(0)	0.23 ± 0.04	0.27 ± 0.03	0.25 ± 0.02
yield (Y_VFA)	g COD_VFA/g TVS₍₀₎	0.24 ± 0.06	0.39 ± 0.04	0.40 ± 0.03

In the FL-I, the higher OLR (due to the higher OFMSW content in the feedstock) resulted in lower conversion yield of total COD into COD_SOL and VFA, in accordance to what reported by Hao et al. (22) In spite of this, both higher COD_SOL and VFA concentration were observed. In particular, VFA trend was characterized by significant fluctuation of VFA concentration with maximum value up to 35 g COD_VFA/L. As a consequence, the pH was lower than in the following periods, on average, and often below 5.0. Moreover, even though both VFA concentration and COD_SOL were higher in FL-I (23 ± 6 g COD_VFA/L and 45 ± 8 g COD_SOL/L), the COD_VFA/COD_SOL ratio was consistently lower (0.53 ± 0.11), meaning that a significant fraction of solubilized COD (or TVS) was not converted into VFA.

By decreasing the OFMSW content (and correspondingly the OLR), a more stable VFA production was observed, even with lower average value 21 ± 3 (FL-II). Girotto and co-workers also observed lower VFA production by decreasing food waste load in batch acidogenic fermentation test. (23) The authors negatively highlighted this fact; however, in continuous process configuration as used in this platform, lower OLR allowed for a better control of acidogenic activity since the pH of the system was easily maintained slightly above 5.0. Thermophilic conditions led to a significant COD_TOT and TVS solubilization, even higher than those measured in condition I, which performances were strongly affected by system stability. Higher COD and TVS conversion into VFA were also observed (COD_VFA/COD_SOL ratio 0.64 ± 0.07).

Despite the lowest average VFA concentration (19 ± 2), FL-III seemed to be more suitable, giving the highest COD_VFA/COD_SOL ratio at 0.75 ± 0.09, a crucial parameter for an efficient selection/enrichment of a PHA-accumulating consortium. (6,18) The temperature of 42 °C led to lower COD solubilization (0.10 g COD_SOL/g COD_TOT(0) and 0.15 g COD_SOL/g TVS₍₀₎) but comparable VFA yields to thermophilic condition (FL-II). The measured yield was 0.40 g COD_VFA/g TVS₍₀₎, lower than those reported in some literature examples for OFMSW, 0.5–0.9 g COD_VFA/g TVS. (24) This difference could be reasonably attributed to the presence of sewage sludge in the mixture.

In terms of composition, butyric acid was predominant in FL-I (46% of total VFA, COD basis), followed by acetic (22%) and propionic (9%) acids. Other VFAs with higher molecular weight (up to C7) had lower concentrations (Figure 2B). By decreasing the OFMSW content and OLR in FL-II, a remarkable increase of acetic acid was quantified (28%), whereas the amount of butyric acid was considerably reduced to 28%. In addition, the content of caproic acid increased up to 15%, as well as for heptanoic acid (6%). A further increase of acetic (33%) and heptanoic (11%) acids was obtained in FL-III. On the contrary, butyric acid was further reduced to 25%. Despite of these differences in concentration, the VFA composition in FL-III was more similar to that of FL-II rather than FL-I. This similarity suggested that temperature did not have relevant effect on the final acids distribution (at least in the explored range).

For the three conditions tested, despite some differences in VFA distribution, the molar fraction of acids containing an odd number of carbon atoms (propionic, valeric, isovaleric and heptanoic etc.) with respect to total VFA [C₃/(C₃ + C₂)_VFA] was similar and strongly oriented to the predominance of acids with even number of C atoms (0.17 ± 0.02 mol/mol at maximum in FL-II). It is well-known that this parameter can be used to characterize complex VFA mixtures and to predict polymer composition in terms of monomers stoichiometry. (6,25)

In terms of continuous process operation, the process stability was strongly affected by the relative OFMSW and SS content (and consequent change of OLR); in particular, OFMSW volumetric percentage between 40 and 45% led to frequent spots of high VFA content not balanced by mixture buffering capacity. This caused an unstable VFA production for both concentration and composition with possible difficulties in the operations of the two following aerobic stages and likely affecting final polymer composition. (26) By decreasing OFMSW content to 30–35%, the OLR decreased, whereas the buffer capacity increased. As a result, VFA production was steadily maintained for the whole operation period and, importantly, the effluent presented a lower fraction of COD_SOL other than VFA. As mentioned above, a centrifuge filter has been used to obtain a filtered VFA-rich stream for selection and production of PHA-accumulating biomass.

The characterization of the fermented effluent after filtration (fFL) indicated a high volumetric recovery of filtrate (90–95% v/v of the feeding slurry) having TSS level between 5 and 8 g/L in the filtrate. Soluble COD and VFA were not affected by the filtration at all as well as for soluble nutrient level.

3.2. Biomass Selection/Enrichment under Aerobic Dynamic Feeding

After the inoculum, the adaptation of the biomass to the imposed dynamic feeding was easily evaluated by monitoring the dissolved oxygen (DO) concentration as illustrated in the representative example of Figure 3A. The DO concentration decreased to around 2.0 mg/L at the beginning of the cycle (fFL feeding), as a consequence of the increase of the metabolic activity. (27) After VFA (or most of COD_SOL) depletion, DO concentration started to increase and it stabilized approximately at 6.0 mg/L and slowly returned back to the initial value during the slowly biodegradable COD consumption. Indeed, the sharp increase of DO concentration was due to the consumption of the readily biodegradable COD, mainly consisting of VFA. This point has been recognized as “feast phase length”. PHA concentration profile confirmed the occurrence of feast–famine regime: The maximum PHA level was quantified at the end the feast phase (with almost complete VFA exhaustion) and then degraded over the course of remaining part of the cycle (Figure 3A).

Figure 3. Main parameters monitored in SBR: VFA, COD_SOL, PHA, ammonium, and phosphate in a typical SBR FL-III cycle (A). Feast phase/cycle length ratio (B), maximum and minimum PHA concentration (C), and storage rate and yield (D) in the three different SBR runs.

The ratio “feast phase/cycle length” was regularly measured and used to monitor biomass adaptation and process stability. From Figure 3B, acclimating biomass needed less than 1 week of operation (∼4/5 SRT) to achieve a stable response to the imposed dynamic feeding condition. Despite of the different COD_VFA/COD_SOL ratio of fFL-I, -II, and -III, the biomass behavior showed a certain stability as indicated by the low feast/cycle time ratio during the whole SBR run, with a maximum of 0.22 h/h, (with the exception of the first day after inoculum) and the short fluctuations casually recorded were no more than 1 day long or even less (Figure 3B). This indicated that the process was technically feasible for long-term operation, despite the presence of changing inputs. Average values of feast phase were 0.14 ± 0.05, 0.11 ± 0.02, and 0.10 ± 0.02 h/h in runs FL-I, FL-II, and FL-III, respectively, abundantly lower than largely recognized threshold of 0.2 h/h, necessary to achieve an efficient biomass selective pressure. (4,11) A slight decrease of F/F ratio was observed when moving from FL-I to FL-III, which can be likely linked to the corresponding increase of VFA/COD_SOL ratio in the feed.

The storage response was consequently expected to be strong and robust, and it was verified especially in run FL-II and FL-III where the difference between PHA concentration at the end of feast and the end of famine were higher and characterized by less variability with respect to run FL-I (Figure 3C).

Consequently, based on increasing effectiveness of dynamic feeding regime, biomass storage properties progressively increased as also indicated by the evolution of specific storage rate and yield (Figure 3D). (28) It is reasonable to suppose that the higher stability of biomass storage response was primarily favored by the equally more stable fermentation performance (in particular yield and VFA concentration), which made easier the operation of SBR. In addition, it was observed from recorded cycles profiles that non-VFA COD_SOL contributed only in minor part to PHA storage, as also reported in literature. (16,29) This observation was confirmed by the quite similar average storage yields quantified in run FL-III: Y_P/S^feast and Y_P/VFA^feast were equal to 0.36 ± 0.04 and 0.40 ± 0.04, respectively. This non-VFA COD_SOL can favor the growth of nonstoring bacteria during the famine phase, causing a less efficient culture selection. (30) Therefore, the progressive increase of VFA/COD_SOL ratio along the SBR operation had a significant impact on selective pressure and, as a consequence, on biomass storage properties.

Quantitatively, both specific storage rate and storage yield were strongly correlated with the increasing VFA/COD_SOL ratio of used fFL, as easily deducible from Table 3, where the main parameters measured in the three periods of SBR run are reported.

Table 3. Main Parameters (Average Values and Standard Deviations) Monitored in the SBR Runs

		average value
parameter	unit	run FL-I	run FL-II	run FL-III
TSS	mg TSS/L	2717 ± 132	1912 ± 64	1930 ± 101
VSS	mg VSS/L	2136 ± 95	1510 ± 61	1718 ± 78
VSS/TSS		0.79 ± 0.02	0.80 ± 0.01	0.88 ± 0.01
feast phase/cycle length ratio	h/h	0.14 ± 0.05	0.11 ± 0.02	0.10 ± 0.02
PHA (end of feast)	mg PHA/L	228 ± 58	196 ± 30	200 ± 16
PHA (end of famine)	mg PHA/L	104 ± 24	34 ± 12	20 ± 9
HV fraction	g HV/g PHA (%)	13.7 ± 0.4	16.1 ± 0.8	14 ± 1
specific PHA storage rate (qP^feast)	mgCOD_PHA/gCOD_Xa/h	101 ± 52	212 ± 35	258 ± 44
specific VFA removal rate (−qVFA^feast)	mgCOD_VFA/gCOD_Xa/h	332 ± 62	619 ± 54	634 ± 53
specific COD removal rate (−qS^feast)	mgCOD_SOL/gCOD_Xa/h	509 ± 84	840 ± 77	725 ± 62
storage yield (Y_P/S^feast)	COD_PHA/COD_SOL	0.22 ± 0.05	0.26 ± 0.06	0.36 ± 0.04
storage yield (Y_P/VFA^feast)	COD_PHA/COD_VFA	0.30 ± 0.06	0.34 ± 0.05	0.40 ± 0.04
observed yield (Y_OBS^SBR)	COD_VSS/COD_SOL	0.49 ± 0.05	0.42 ± 0.06	0.54 ± 0.08
effluent ammonia (N–NH₄⁺)	mg N–NH₄⁺/L	2.6 ± 1.2	0.8 ± 0.5	3.5 ± 0.9
effluent phospahte (PO₄^3–)	mg P–PO₄^3–/L	1.8 ± 0.5	1.9 ± 0.4	2.1 ± 0.3
effluent COD_SOL	mg COD_SOL/L	204 ± 37	102 ± 24	116 ± 8

Ammonium, phosphate, and COD_SOL concentrations were systematically measured in SBR effluent (Table 3). Despite different characteristics of the three fFL, the selection stage provided stable performance for carbon and nutrients removal. The percentage of removal from the influent was in a narrow range between the three runs: 85–97%, 69–82%, and 86–92% for ammonium, phosphate, and COD_SOL respectively.

3.3. PHA Accumulation

The PHA accumulation capacity of selected PHA-storing biomass was evaluated in fed-batch accumulation tests by means of multispike feeding strategy. (27) To do so, fFLs effluents were further refined by means of filtration on the filter press above-described (for fFL-II and fFL-III only) in order to obtain a refined filtered fermented liquids (ffFLs) characterized by no content of suspended solids.

Multiple pulsed additions of ffFL-II and ffFL-III was used to overcome any potential substrate inhibition phenomena. (14,27,31) As an example, Figure 4 shows the profile of PHA biomass content, VFA and PHA concentration during a typical accumulation test performed with run FL-III biomass, fed with either acetate as benchmark (Figure 4A) or ffFL-III (Figure 4B). In both cases, PHA production occurred linearly for at least 3 h, although at different rate. In the case of acetate, the PHA biomass content increased linearly up to 0.40 g PHA/g VSS; then, PHA production was no longer sustained and acetate uptake rate was remarkably reduced after the last pulse addition (4 h). On the other hand, a faster VFA depletion was observed with ffFL-III, at least within the four initial hours. This relatively high VFA uptake rate was associated with a considerable polymer production, since PHA concentration increased almost linearly in the first 4 h of accumulation and its biomass content reached 0.45 g PHA/g VSS. Afterward, VFA started to be consistently accumulated in the reactor and PHA was produced with a lower rate, achieving a final concentration above 2.0 g/L and PHA biomass content of 0.48 g PHA/g VSS. Quantitatively, PHA concentration was almost doubled, and PHA biomass content was roughly 20% higher than those obtained with acetate accumulation. This was likely due to the presence of nutrients in the carbon source, which probably did not limit the microbial activity in terms of PHA storage and new PHA-storing biomass growth. On the contrary, the acetate synthetic solution did not allow the growth of new biomass, and as a consequence, the whole PHA production potential of the consortium was limited.

Figure 4. Fed-batch accumulations conducted with biomass enriched in SBR FL-III run: synthetic acetate (A) and ffFL-III (B) as feeding solutions.

These results highlighted the importance of the nutrients in the expression of storage potential of biomass appropriately selected. Lack of nutrients is not always better than excess and/or partial limitation of nutrients, (32,33) especially if biomass response needs to be exploited to a large extent. (6) In the examined examples, PHA storage had been favored by the presence of nutrients (partially limiting respect to COD_SOL) and consequently by the simultaneous growth of PHA-storing organisms. However, better performance with ffFLs than that with acetate can also be due to the SBR biomass having been selected with a very similar fFL mixture instead of with pure acetate.

Table 4 summarizes the main outcomes of conducted accumulations. A first comparison with previous lab-scale investigation adopting an identical process configuration highlighted the promising results obtained in this study. (18) Similar PHA content and yield were achieved with even higher polymer productivity (up to 0.36 g PHA/L h), favored by the presence of nutrients and, as a consequence, by the growth of new active PHA-storing biomass during accumulation. Other investigations utilizing OFMSW sources have been mostly conducted at laboratory scale, at least for the aerobic process steps. (14−16,34) Amulya and co-workers proposed an integrated multistage approach for food waste valorization. (34) In that study, PHA production was strongly limited by low VFA level in the fermented feedstock (approximately 6.0 g COD_VFA/L), which made it difficult to operate at relatively high OLR. Hence, enriched biomass produced PHA with a specific rate of 11–42 mg COD_PHA/g COD_Xa/h, 1 order of magnitude lower than this study, 279–301 mg COD_PHA/g COD_Xa/h. Maximal PHA content achieved was 0.24 g PHA/g VSS, negatively affected by the abundant amount of COD_SOL other than VFA. Basset et al. used OFMSW FL alternatively mixed with PS. (16) The approach proposed by the authors was different from this pilot-scale demonstration, since it consisted in an integration of MMC selection with nitrogen removal (through aerobic–anoxic feast–famine regime) in a municipal WW treatment line. As a consequence, the storage performances quantified in fed-batch tests were still far, even though not properly comparable, from those exhibited by the fully aerobically selected biomass.

Table 4. Summary of Main Results Obtained in Fed-Batch Accumulations and Comparison with Previous Studies Focused on Food Waste Valorization

VFA-rich stream	PHA content (gPHA/gVSS)	PHA composition (wt % HB/HV)	Y_P/S^batch^a	Y_P/VFA^batch^a	Y_X/S^batch^a	Y_X/VFA^batch^a	qP^batch (mgCOD_PHA/gCOD_Xa/h)	PHA productivity (gPHA/L h)	refs
acetate (synth.)^b	0.40 ± 0.02	100/0		0.67 ± 0.05		0.08 ± 0.01	202 ± 33	0.20 ± 0.04	this study
OFMSW-SS mixture (ffFL-II)^f	0.43 ± 0.01	87/13	0.37 ± 0.06	0.44 ± 0.03	0.22 ± 0.05	0.24 ± 0.07	301 ± 81	0.29 ± 0.04	this study
OFMSW-SS mixture (ffFL-III)^f	0.46 ± 0.05	90/10	0.41 ± 0.05	0.50 ± 0.04	0.21 ± 0.01	0.26 ± 0.08	279 ± 41	0.36 ± 0.05	this study
pretreated OFMSW	0.39–0.52	7–13/93–87	0.39–0.47	0.43–0.57	0.18–0.24	0.19–0.28	255–436	0.28–0.49	(13)
leachate	0.78^c^,^d			0.33^c–0.40^d					(14)
percolate^f	0.41–0.48	54–57/46–43	0.44–0.52	0.66–1.13				0.18–0.29	(15)
OFMSW^f	0.11		0.08	0.22	0.77	0.36	20		(16)
OFMSW-PS^e mixture^f	0.09		0.003	0.011	0.79	0.47	11		(16)
VFA mixture (synth.)^b	0.48 ± 0.03	88/12		0.53 ± 0.03			196 ± 13	0.17 ± 0.02	(18)
food waste (FW)^f	0.24	60/40	0.09–0.17				11–42		(34)

^{^a}

COD basin.

^{^b}

No nutrients addition (COD/N/P = 100:0:0).

^{^c}

Biomass enriched with synthetic VFA mixture (90% v/v) and leachate (10% v/v).

^{^d}

Biomass enriched with synthetic VFA mixture (75% v/v) and leachate (25% v/v).

^{^e}

Primary sludge.

^{^f}

Fermented feedstock.

Better performance was obtained with leachate and percolate. (14,15) In the first case, the biomass was able to accumulate high level of polymer (0.78 g PHA/g VSS), but it has to be considered that its enrichment in SBR had been performed with a synthetic mixture mainly composed of acetate (75–90% v/v). The storage performances obtained with percolate were comparable with those obtained with ffFL-III with the exception for the composition of produced PHA. Percolate was characterized by higher level of HV precursor (mainly propionic acid, 29–46% w/w); HB and HV monomer fractions were consequently closer (54–57% and 46–43% g/g for HB and HV respectively) if compared to those fractions derived from ffFL-III (90% HB and 10% HV weight basis).

More recently, Valentino et al. (13) described a multistep pilot-scale platform for the conversion of pretreated OFMSW (not mixed with sludge) into PHA and biogas. Regarding the aerobic stage performances, the obtained results were comparable in terms of PHA production rate and yield, volumetric productivity, and polymer composition. However, compared to the previous approach, (13) the process scheme herein proposed offers the possibility for a simultaneous treatment of two different streams collected in the same urban area. In this way, a single technology can be used for efficient and integrated urban waste management.

3.4. Overall PHA Yield and Possible Future Perspective

Data analysis of each pilot unit, including the two solid/liquid separation units (“C” and “F”), have been related to the quantification of the overall PHA yield. This number indicates the amount of TVS necessary for the production of 1.0 kg of PHA, which corresponds to 1.70 kg of COD_PHA, based on quantified HB–HV wt % monomers composition. The relative mass flow diagram of PHA production is depicted in Figure 5. The backward calculation started from the final PHA biomass content of 0.46 g PHA/g VSS, obtained with fFL-III as feed solution (Table 3). This PHA content means a production of 1.17 kg (or 1.66 kg of COD) of active biomass X_A. For both produced X_A and PHA, it has been estimated a total consumption of 6.24 kg of COD_VFA, of which 3.38 kg of COD_VFA for polymer production in batch accumulation reactor and 2.86 for X_A production in SBR enrichment reactor. These separated contributions have been quantified based on the process yields the storage yield (Y_P/VFA^batch) of 0.50 COD_PHA/COD_VFA (Table 3), and the X_A observed yield (Y_Xa^SBR) of 0.58 COD_Xa/COD_VFA, for PHA and X_A production, respectively. Since the use of filter press reduced the volumetric load of fFL of 5% v/v with respect to influent FL, the equivalent amount of VFA has to be increased up to 3.56 kg of COD_VFA. This led to 6.42 kg of COD_VFA in the centrifuged FL, as quantified VFA consumption in both aerobic stages for each kilogram of produced PHA. In addition, taking into account the slight retention of FL in the filter bag centrifuge (roughly 5%), it has been overall estimated a total consumption of 6.76 kg of COD_VFA, which corresponds to 356 L of FL-III at a VFA level of 19.0 g COD/L. By considering the TVS concentration of 43 g/kg in the initial feedstock (before acidogenic fermentation), the amount of TVS needed for the production of 1.0 kg PHA is 15.3 kg of TVS, which corresponds to an overall yield of 65 g PHA/kg TVS. Such deep analysis is rarely reported in the literature, and the recent practical advancements of the MMC technology on the pilot-scale platforms showed yields in the same order of magnitude. Colombo and co-workers reported a global yield in the range 62.9–114 g PHA/kg TS by using the percolate fraction of fermented OFMSW; however, only the first fermentation step was performed at pilot scale. (15) In a more recent study, a complete pilot system was developed for the valorization of the OFMSW as the only carbon source. (13) From the mass balance assessment, the authors quantified an overall yield of 37 g PHA/kg TVS. Hence, the approach described in this study increased the yield of 40% approximately.

Figure 5. Mass flow diagram of PHA production from OFMSW-SS mixture.

In the perspective of a future market scenario for PHA synthesized by MMC, the maximization of the yield could have a remarkable impact on the process sustainability. Moreover, in a multisteps biorefinery approach, the simultaneous bioproducts and biogas production from the same organic feedstock could be more beneficial compared to a single product recovery. With reference to the same urban scenario described in this study, Moretto and co-workers quantified a maximum economic income of 245 000 €/year from the electrical energy produced in the Treviso full-scale anaerobic digestion (AD) plant. (35) The 2000 m³ AD reactor was designed for the treatment of OFMSW-SS mixture (roughly 1150 ton TVS/year), produced in an urban scenario of 70 000 Person Equivalent (PE). (35)

With the introduction of a designed PHA line, it can be estimated a request of the 60% of the organic solids (690 ton TVS/year) for the fermentation step and the production of a liquid VFA-rich stream amenable for PHA synthesis. (36) Based on the calculated yield (65 g PHA/kg TVS), a production of 45 ton PHA/year can be counted. Following the approach described in Valentino et al., the residual TVS amount (overflows) is represented by the sum of the 40% unfermented solids (460 ton TVS/year) and the solid-rich prefermented fraction (“cake”), which is discharged from the solid/liquid separation unit (80% of the fermentation TVS influent; 552 ton TVS/year). (36) From the specific gas production (SGP) quantified in the mesophilic AD treatment of the overflows (0.40 m³ biogas/kg TVS), (36) the estimated biogas production is 1124 m³/day. The technical feasibility of this approach has been recently demonstrated; (36) a revenue of 134 591 €/year is achievable from the sale of generated electricity (13.03 MWh/day). (36) In theory, taking into account an average PHA value of 4000 €/ton, (5) an additional revenue of 180 000 €/year has to be considered, potentially making the biorefinery platform a more profitable solution if compared to the traditional AD process.

4. Conclusions

Click to copy section linkSection link copied!

The present pilot-scale plant is an example of novel “biorefinery” for urban waste valorisation, providing an option to implement a synergic treatment of relevant organic waste streams produced and collected in the same urban area. The overall process yield of PHA production from selected organic waste has been estimated to 6.5 wt % with respect to the TVS on untreated waste stream, composed by the source sorted OFMSW and sewage sludge. In addition, a possible integration of the proposed approach could be the valorization of the solid-rich overflow, mainly produced by the filter bag centrifuge and basically composed by fermented OFMSW–SS through anaerobic digestion (AD). (35) This solution allows using one main technology for the conversion of urban biowastes into PHA, while also minimizing any residual or consequent waste to be disposed.

This work demonstrated how the innovation in urban waste management could contribute to better waste collection and processing for the production of higher value biobased products.

Author Information

Click to copy section linkSection link copied!

Corresponding Author
- Francesco Valentino - Department of Chemistry, “La Sapienza” University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; http://orcid.org/0000-0003-2016-4347; Email: [email protected]
Authors
- Giulia Moretto - Department of Environmental Science, Informatics and Statistics, Via Torino 155, 30170 Venezia Mestre, Italy
- Laura Lorini - Department of Chemistry, “La Sapienza” University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
- David Bolzonella - Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
- Paolo Pavan - Department of Environmental Science, Informatics and Statistics, Via Torino 155, 30170 Venezia Mestre, Italy
- Mauro Majone - Department of Chemistry, “La Sapienza” University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
Notes
The authors declare no competing financial interest.

Acknowledgments

Click to copy section linkSection link copied!

This work was supported by the REsources from URban BIo-waSte” - RES URBIS (GA 7303499) project in the European Horizon2020 (Call CIRC-05-2016) program.

References

Click to copy section linkSection link copied!

This article references 36 other publications.

1
Morgan-Sagastume, F. Characterisation of open, mixed microbial cultures for polyhydroxyalkanoate (PHA) production. Rev. Environ. Sci. Bio/Technol. 2016, 15, 593– 625, DOI: 10.1007/s11157-016-9411-0
Google Scholar
1
Characterisation of open, mixed microbial cultures for polyhydroxyalkanoate (PHA) production
Morgan-Sagastume, Fernando
Reviews in Environmental Science and Bio/Technology (2016), 15 (4), 593-625CODEN: RESBC6; ISSN:1569-1705. (Springer)
A review. The microbial community structure and population dynamics in both the biomass enrichment and the PHA accumulation process have not been equally analyzed. PHA-storing bacteria have been identified predominantly within the classes of Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria. Mol. techniques and microscopy have been preferentially used to characterize microbial diversity, abundance and activity in PHA-storing MMC. Fluorescence in situ hybridization remains relevant for the spatial identification and quantification of PHA-storing bacteria, and in tandem with Nile blue A staining helps identify actively PHA-storing bacteria. 16S rRNA-based fingerprinting is useful for describing dynamics in microbial community structure rather than diversity, and new generation sequencing provides a high-throughput characterization of microbial diversity, dynamics and relative abundance. The dominant bacteria and their dynamics in bioreactors enriching for MMC with PHA-storage capacity and actively accumulating PHA are further covered with respect to the operating conditions used to select microbial communities for the PHA-storage phenotype. The specification of the PHA-storage phenotype and metabolic activity in identified bacteria remains a challenge in the study of PHA-storing MMC.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhslygtbvI&md5=d372b09d707cfe56c6bc8d365be8fbd7
2
Kourmentza, C.; Plácido, J.; Venetsaneas, N.; Burniol-Figols, A.; Varrone, C.; Gavala, H. N.; Reis, M. A. M. Recent advances and challenges towards sustainable polyhydroxyalkanoate (PHA) production. Bioengineering 2017, 4, 55, DOI: 10.3390/bioengineering4020055
Google Scholar
There is no corresponding record for this reference.
3
Rodriguez-Perez, S.; Serrano, A.; Pantión, A. A.; Alonso-Farinas, B. Challenges of scaling-up PHA production from waste streams. A review. J. Environ. Manage. 2018, 205, 215– 230, DOI: 10.1016/j.jenvman.2017.09.083
Google Scholar
3
Challenges of scaling-up PHA production from waste streams. A review
Rodriguez-Perez, Santiago; Serrano, Antonio; Pantion, Alba A.; Alonso-Farinas, Bernabe
Journal of Environmental Management (2018), 205 (), 215-230CODEN: JEVMAW; ISSN:0301-4797. (Elsevier Ltd.)
The search for new materials that replace fossil fuel-based plastics has been focused on biopolymers with similar physicochem. properties to fossil fuel-based plastics, such as Polyhydroxyalkanoates (PHA). The present paper reviews the challenges of scaling-up PHA prodn. from waste streams during the period from 2014 to 2016, focusing on the feasibility of the alternatives and the most promising alternatives to its scaling-up. The reviewed research studies mainly focus on reducing costs or obtaining more valuable polymers. In the future, the integration of PHA prodn. into processes such as wastewater treatment plants, hydrogen prodn. or biodiesel factories could enhance its implementation at industrial scale.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhs1akur7K&md5=0d7e6f6829ab0015407b8ad570fe7db4
4
Valentino, F.; Morgan-Sagastume, F.; Campanari, S.; Villano, M.; Werker, A.; Majone, M. Carbon recovery from wastewater through bioconversion into biodegradable polymers. New Biotechnol. 2017, 37, 9– 23, DOI: 10.1016/j.nbt.2016.05.007
Google Scholar
4
Carbon recovery from wastewater through bioconversion into biodegradable polymers
Valentino, Francesco; Morgan-Sagastume, Fernando; Campanari, Sabrina; Villano, Marianna; Werker, Alan; Majone, Mauro
New Biotechnology (2017), 37 (Part_A), 9-23CODEN: NBEIBR; ISSN:1871-6784. (Elsevier B.V.)
Polyhydroxyalkanoates (PHA) are biodegradable polyesters that can be produced in bioprocesses from renewable resources in contrast to fossil-based bio-recalcitrant polymers. Research efforts have been directed towards establishing tech. feasibility in the use of mixed microbial cultures (MMC) for PHA prodn. using residuals as feedstock, mainly consisting of industrial process effluent waters and wastewaters. In this context, PHA prodn. can be integrated with waste and wastewater biol. treatment, with concurrent benefits of resource recovery and sludge minimization. Over the past 15 years, much of the research on MMC PHA prodn. has been performed at lab. scale in three process elements as follows: (1) acidogenic fermn. to obtain a volatile fatty acid (VFA)-rich stream, (2) a dedicated biomass prodn. yielding MMCs enriched with PHA-storing potential, and (3) a PHA accumulation step where (1) and (2) outputs are combined in a final biopolymer prodn. bioprocess. This paper reviews the recent developments on MMC PHA prodn. from synthetic and real wastewaters. The goals of the crit. review are: a) to highlight the progress of the three-steps in MMC PHA prodn., and as well to recommend room for improvements, and b) to explore the ideas and developments of integration of PHA prodn. within existing infrastructure of municipal and industrial wastewaters treatment. There has been much tech. advancement of ideas and results in the MMC PHA rich biomass prodn. However, clear demonstration of prodn. and recovery of the polymers within a context of product quality over an extended period of time, within an up-scalable com. viable context of regional material supply, and with well-defined quality demands for specific intent of material use, is a hill that still needs to be climbed in order to truly spur on innovations for this field of research and development.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhtVGit77O&md5=f2914ad754e3112c414c543569a0e864
5
Gholami, A.; Mohkam, M.; Rasoul-Amini, S.; Ghasemi, Y. Industrial production of polyhydroxyalkanoates by bacteria: opportunities and challenges. Minerva Biotechnol. 2016, 28, 59– 74
Google Scholar
There is no corresponding record for this reference.
6
Morgan-Sagastume, F.; Hjort, M.; Cirne, D.; Gérardin, F.; Lacroix, S.; Gaval, G.; Karabegovic, L.; Alexandersson, T.; Johansson, P.; Karlsson, A.; Bengtsson, S.; Arcos-Hernández, M.; Magnusson, P.; Werker, A. Integrated production of polyhydroxyalkanoates (PHAs) with municipal wastewater and sludge treatment at pilot scale. Bioresour. Technol. 2015, 181, 78– 89, DOI: 10.1016/j.biortech.2015.01.046
Google Scholar
6
Integrated production of polyhydroxyalkanoates (PHAs) with municipal wastewater and sludge treatment at pilot scale
Morgan-Sagastume, F.; Hjort, M.; Cirne, D.; Gerardin, F.; Lacroix, S.; Gaval, G.; Karabegovic, L.; Alexandersson, T.; Johansson, P.; Karlsson, A.; Bengtsson, S.; Arcos-Hernandez, M. V.; Magnusson, P.; Werker, A.
Bioresource Technology (2015), 181 (), 78-89CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
A pilot-scale process was operated over 22 mo at the Brussels North Wastewater Treatment Plant (WWTP) in order to evaluate polyhydroxyalkanoate (PHA) prodn. integration with services of municipal wastewater and sludge management. Activated sludge was produced with PHA accumulation potential (PAP) by applying feast-famine selection while treating the readily biodegradable COD from influent wastewater (av. removals of 70% COD, 60% CODsol, 24% nitrogen, and 46% phosphorus). The biomass PAP was evaluated to be in excess of 0.4 gPHA/gVSS. Batch fermn. of full-scale WWTP sludge at selected temps. (35, 42 and 55 °C) produced centrate (6-9.4 gCODVFA/L) of consistent VFA compn., with optimal fermn. performance at 42 °C. Centrate was used to accumulate PHA up to 0.39 gPHA/gVSS. The centrate nutrients are a challenge to the accumulation process but producing a biomass with 0.5 gPHA/gVSS is considered to be realistically achievable within the typically available carbon flows at municipal waste management facilities.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhsVans7Y%253D&md5=139eac0ce5d09ef3d7176ea108ce1292
7
Bengtsson, S.; Karlsson, A.; Alexandersson, T.; Quadri, L.; Hjort, M.; Johansson, P.; Morgan-Sagastume, F.; Anterrieu, S.; Arcos-Hernandez, M.; Karabegovic, L.; Magnusson, P.; Werker, A. A process for polyhydroxyalkanoate (PHA) production from municipal wastewater treatment with biological carbon and nitrogen removal demonstrated at pilot-scale. New Biotechnol. 2017, 35, 42– 53, DOI: 10.1016/j.nbt.2016.11.005
Google Scholar
7
A process for polyhydroxyalkanoate (PHA) production from municipal wastewater treatment with biological carbon and nitrogen removal demonstrated at pilot-scale
Bengtsson, Simon; Karlsson, Anton; Alexandersson, Tomas; Quadri, Luca; Hjort, Markus; Johansson, Peter; Morgan-Sagastume, Fernando; Anterrieu, Simon; Arcos-Hernandez, Monica; Karabegovic, Lamija; Magnusson, Per; Werker, Alan
New Biotechnology (2017), 35 (), 42-53CODEN: NBEIBR; ISSN:1871-6784. (Elsevier B.V.)
A process was developed for biol. treatment of municipal wastewater for carbon and nitrogen removal while producing added-value polyhydroxyalkanoates (PHAs). The process comprised steps for pre-denitrification, nitrification and post-denitrification and included integrated fixed-film activated sludge (IFAS) with biofilm carrier media to support nitrification. In a pilot-scale demonstration (500-800 L), wastewater treatment performance, in line with European stds., were achieved for total COD (83% removal) and total nitrogen (80% removal) while producing a biomass that was able to accumulate up to 49% PHA of volatile suspended solids with acetic acid or fermented org. residues as substrates. Robust performance in wastewater treatment and enrichment of PHA-producing biomass was demonstrated under realistic conditions including influent variability during 225 days of operation. The IFAS system was found to be advantageous since maintaining nitrification on the biofilm allowed for a relatively low (2 days) solids retention time (SRT) for the suspended biomass in the bulk phase. Lower SRT has advantages in higher biomass yield and higher active fraction in the biomass which leads to higher PHA productivity and content. The outcomes show that prodn. of added-value biopolymers may be readily integrated with carbon and nitrogen removal from municipal wastewater.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XitFGnsbbM&md5=8bae4266f36650fc46e3330579400659
8
Jia, Q.; Xiong, H.; Wang, H.; Shi, H.; Sheng, X.; Sun, R.; Chen, G. Production of polyhydroxyalkanoates (PHA) by bacterial consortium from excess sludge fermentation liquid at laboratory and pilot scales. Bioresour. Technol. 2014, 171, 159– 167, DOI: 10.1016/j.biortech.2014.08.059
Google Scholar
8
Production of polyhydroxyalkanoates (PHA) by bacterial consortium from excess sludge fermentation liquid at laboratory and pilot scales
Jia, Qianqian; Xiong, Huilei; Wang, Hui; Shi, Hanchang; Sheng, Xinying; Sun, Run; Chen, Guoqiang
Bioresource Technology (2014), 171 (), 159-167CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
The generation of polyhydroxyalkanoates (PHA) from excess sludge fermn. liq. (SFL) was studied at lab and pilot scale. A PHA-accumulated bacterial consortium (S-150) was isolated from activated sludge using simulated SFL (S-SFL) contained high concn. volatile fatty acids (VFA) and nitrogen. The maximal PHA content accounted for 59.18% in S-SFL and dropped to 23.47% in actual SFL (L-SFL) of the dry cell wt. (DCW) at lab scale. The pilot-scale integrated system comprised an anaerobic fermn. reactor (AFR), a ceramic membrane system (CMS) and a PHA prodn. bio-reactor (PHAR). The PHA content from pilot-scale SFL (P-SFL) finally reached to 59.47% DCW with the maximal PHA yield coeff. (YP/S) of 0.17 gPHA/gCOD. The results indicated that VFA-contg. SFL was suitable for PHA prodn. The adverse impact of excess nitrogen and non-VFAs in SFL might be eliminated by pilot-scale domestication, which might resulted in community structure optimization and substrate selective ability improvement of S-150.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhsVKntr%252FO&md5=ab0f27b2dd414a3774b23afd680b8fa0
9
Chakravarty, P.; Mhaisalkar, V.; Chakrabarti, T. Study on polyhydroxyalkanoate (PHA) production in pilot scale continuous mode wastewater treatment system. Bioresour. Technol. 2010, 101, 2896– 2899, DOI: 10.1016/j.biortech.2009.11.097
Google Scholar
9
Study on poly-hydroxyalkanoate (PHA) production in pilot scale continuous mode wastewater treatment system
Chakravarty, Partha; Mhaisalkar, Vasant; Chakrabarti, Tapan
Bioresource Technology (2010), 101 (8), 2896-2899CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
Generation of polyhydroxyalkanoates (PHAs) from milk and ice-cream processing wastewater was studied in a continuous mode reactor system at pilot scale. The integrated system comprised an anaerobic acidogenic reactor (AAR), a conventional activated sludge prodn. reactor (ASPR) and a PHA synthesis reactor (PHAR) to induce PHA accumulation in the biomass which was finally harvested while treating the raw dairy wastewater to meet the disposal limits thereby reducing generation of disposable sludge. The PHA content in the PHA rich biomass was ∼43% of the sludge dry wt. Kinetics of both ASPR and PHAR were studied. The max. PHA yield coeff. (Ymaxsp) with respect to COD degrdn. in the PHAR was derived as 0.25 kg PHA/kg of COD degraded. Similarly, the kinetic parameters i.e. Ks, μm, Yobs and kd of the ASPR were 37.16 mg/l COD, 0.97 d-1, 0.51 mg MLSS/mg COD and 0.049 d-1, resp.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXjvVekuw%253D%253D&md5=3690860328d3ba6992ce15249099dabd
10
Tamis, J.; Luzkova, K.; Jiang, Y.; van Loosdrecht, M. C. M.; Kleerebezem, R. Enrichment of Plasticicumulans acidivorans at pilot-scale for PHA production on industrial wastewater. J. Biotechnol. 2014, 192, 161– 169, DOI: 10.1016/j.jbiotec.2014.10.022
Google Scholar
10
Enrichment of Plasticicumulans acidivorans at pilot-scale for PHA production on industrial wastewater
Tamis, Jelmer; Luzkov, Katlin; Jiang, Yang; Loosdrecht, Mark C. M. van; Kleerebezem, Robbert
Journal of Biotechnology (2014), 192 (Part_A), 161-169CODEN: JBITD4; ISSN:0168-1656. (Elsevier B.V.)
A PHA producing microbial culture dominated by Plasticicumulans acidivorans was enriched in a pilot plant using fermented wastewater from the Mars candy bar factory. The pilot plant comprised (1) anaerobic fermn., (2) enrichment of a PHA-producing microbial community and (3) accumulation for maximization of the cellular PHA content. After anaerobic fermn., the wastewater contained mainly VFAs (0.64 ± 0.15 gCOD/gCOD) and ethanol (0.22 ± 0.13 gCOD/gCOD). In the enrichment reactor (cycle 12 h, SRT 24 h) a feast-famine pattern was established with a feast phase of around 35 ± 5 min. The culture was able to accumulate 0.70 ± 0.05 gPHA/gVSS. The difference with previous lab-scale results from P. acidivorans, in which a PHA content of 0.90 gPHA/gVSS was achieved, could be attributed to the presence of solids in the influent, the growth of a side population and the accumulation of non-PHA storage compds. that appeared to be related to ethanol consumption.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhvVams7vP&md5=11e29e8e3815deea6ff2f191adb0a969
11
Reis, M. A. M.; Albuquerque, M. G. E.; Villano, M.; Majone, M. Mixed culture processes for polyhydroxyalkanoate production from agroindustrial surplus wastes as feedstocks. Comprehensive Biotechnology 2011, 669– 683, DOI: 10.1016/B978-0-08-088504-9.00464-5
Google Scholar
There is no corresponding record for this reference.
12
Pfaltzgraff, L. A.; De bruyn, M.; Cooper, E. C.; Budarin, V.; Clark, J. H. Food waste biomass: a resource for high-value chemicals. Green Chem. 2013, 15, 307, DOI: 10.1039/c2gc36978h
Google Scholar
12
Food waste biomass: a resource for high-value chemicals
Pfaltzgraff, Lucie A.; De Bruyn, Mario; Cooper, Emma C.; Budarin, Vitaly; Clark, James H.
Green Chemistry (2013), 15 (2), 307-314CODEN: GRCHFJ; ISSN:1463-9262. (Royal Society of Chemistry)
Our society currently faces the twin challenges of resource depletion and waste accumulation leading to rapidly escalating raw material costs and increasingly expensive and restrictive waste disposal legislation. The variety of food processes used in the food and drink industry globally generate food supply chain waste on a multi tonne scale every year. Such resides include wheat straw surpluses, spent coffee grounds or citrus peels, all of which represent a resource for an integrated, product focused biorefinery. Orange peel is particularly interesting: pectin and D-limonene, 2 marketable components, can be produced together with several flavonoids under the same conditions at a liter scale using low temp. microwave treatment. The running costs for such a process on large scale (50,000 metric tonnes/yr) have been estd. on the basis of the combined prodn. of pectin and D-limonene.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXhsVOntr4%253D&md5=b77036666de2e9ba9cb1c9c748f058a8
13
Valentino, F.; Gottardo, M.; Micolucci, F.; Pavan, P.; Bolzonella, D.; Rossetti, S.; Majone, M. Organic fraction of municipal solid waste recovery by conversion into added-value polyhydroxyalkanoates and biogas. ACS Sustainable Chem. Eng. 2018, 6, 16375– 16385, DOI: 10.1021/acssuschemeng.8b03454
Google Scholar
13
Organic Fraction of Municipal Solid Waste Recovery by Conversion into Added-Value Polyhydroxyalkanoates and Biogas
Valentino, Francesco; Gottardo, Marco; Micolucci, Federico; Pavan, Paolo; Bolzonella, David; Rossetti, Simona; Majone, Mauro
ACS Sustainable Chemistry & Engineering (2018), 6 (12), 16375-16385CODEN: ASCECG; ISSN:2168-0485. (American Chemical Society)
The integrated-multistage process proposed herein is a practical example of a biorefinery platform in which the org. fraction of municipal solid waste (OFMSW) is used as a valued source for polyhydroxyalkanoates (PHA) and biogas prodn. Tech. and economical feasibilities of this approach have been demonstrated at pilot-scale, providing a possible upgrade to traditional biowaste management practices, presently based on anaerobic digestion (AD). A pH-controlled OFMSW fermn. stage produced a liq. VFA-rich stream with a high VFA/CODSOL ratio (0.90 COD/COD) that was easily used in the following aerobic stages for biomass and PHA prodn. The solid fraction was valorized into biogas through AD, obtaining energy and minimizing secondary flux waste generation. The reliable biomass enrichment was demonstrated by a stable feast-famine regime and supported by microbial community anal. The selected consortium accumulated PHA up to 55% wt. Compared to the traditional AD process in an urban scenario of 900000 AE, the integrated approach for OFMSW valorization is preferable, and it is characterized by an elec. energy prodn. of 85.7 MWh/d and 1.976 t/d as PHA productivity. The proposed process was also evaluated as economically sustainable if the PHA is marketed from 0.90 euro/kg as the min. threshold to a higher market price.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhvFChsbzK&md5=66ce81b9e5afba63f17526c6fecaf082
14
Korkakaki, E.; Mulders, M.; Veeken, A.; Rozendal, R.; van Loosdrecht, M. C. M.; Kleerebezem, R. PHA production from the organic fraction of municipal solid waste (OFMSW): Overcoming the inhibitory matrix. Water Res. 2016, 96, 74– 83, DOI: 10.1016/j.watres.2016.03.033
Google Scholar
14
PHA production from the organic fraction of municipal solid waste (OFMSW): Overcoming the inhibitory matrix
Korkakaki, Emmanouela; Mulders, Michel; Veeken, Adrie; Rozendal, Rene; van Loosdrecht, Mark C. M.; Kleerebezem, Robbert
Water Research (2016), 96 (), 74-83CODEN: WATRAG; ISSN:0043-1354. (Elsevier Ltd.)
Leachate from the source sepd. org. fraction of municipal solid waste (OFMSW) was evaluated as a substrate for polyhydroxyalkanoates (PHA) prodn. Initially, the enrichment step was conducted directly on leachate in a feast-famine regime. Maximization of the cellular PHA content of the enriched biomass yielded to low PHA content (29 wt%), suggesting that the selection for PHA-producers was unsuccessful. When the substrate for the enrichment was switched to a synthetic volatile fatty acid (VFA) mixt. -resembling the VFA carbon compn. of the leachate-the PHA-producers gained the competitive advantage and dominated. Subsequent accumulation with leachate in nutrient excess conditions resulted in a max. PHA content of 78 wt%. Based on the exptl. results, enriching a PHA-producing community in a "clean" VFA stream, and then accumulating PHA from a stream that does not allow for enrichment but does enable a high cellular PHA content, such as OFMSW leachate, makes the overall process much more economically attractive. The estd. overall process yield can be increased four-fold, in comparison to direct use of the complex matrix for both enrichment and accumulation.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28Xls1Ggsro%253D&md5=5d8b04530373aab084436e9f859962a4
15
Colombo, B.; Favini, F.; Scaglia, B.; Sciarria, T. P.; D’Imporzano, G.; Pognani, M.; Alekseeva, A.; Eisele, G.; Cosentino, C.; Adani, F. Enhanced polyhydroxyalkanoate (PHA) production from the organic fraction of municipal solid waste by using mixed microbial culture. Biotechnol. Biofuels 2017, 10, 201, DOI: 10.1186/s13068-017-0888-8
Google Scholar
15
Enhanced polyhydroxyalkanoate (PHA) production from the organic fraction of municipal solid waste by using mixed microbial culture
Colombo, Bianca; Favini, Francesca; Scaglia, Barbara; Sciarria, Tommy Pepe; D'imporzano, Giuliana; Pognani, Michele; Alekseeva, Anna; Eisele, Giorgio; Cosentino, Cesare; Adani, Fabrizio
Biotechnology for Biofuels (2017), 10 (), 201/1-201/15CODEN: BBIIFL; ISSN:1754-6834. (BioMed Central Ltd.)
In Europe, almost 87.6 million tonnes of food waste are produced. Despite the high biol. value of food waste, traditional management solns. do not consider it as a precious resource. Many studies have reported the use of food waste for the prodn. of high added value mols. Polyhydroxyalkanoates (PHAs) represent a class of interesting bio-polyesters accumulated by different bacterial cells, and has been proposed for prodn. from the org. fraction of municipal solid waste (OFMSW). Nevertheless, until now, no attention has been paid to the entire biol. process leading to the transformation of food waste to org. acids (OA) and then to PHA, getting high PHA yield per food waste unit. In particular, the acid-generating process needs to be optimized, maximizing OA prodn. from OFMSW. To do so, a pilot-scale Anaerobic Percolation Biocell Reactor (100 L in vol.) was used to produce an OA-rich percolate from OFMSW which was used subsequently to produce PHA. The optimized acidogenic process resulted in an OA prodn. of 151 g kg-1 from fresh OFMSW. The subsequent optimization of PHA prodn. from OA gave a PHA prodn., on av., of 223 ± 28 g kg-1 total OA fed. Total mass balance indicated, for the best case studied, a PHA prodn. per OFMSW wt. unit of 33.22 ± 4.2 g kg-1 from fresh OFMSW, corresponding to 114.4 ± 14.5 g kg-1 of total solids from OFMSW. PHA compn. revealed a hydroxybutyrate/hydroxyvalerate (%) ratio of 53/47 and Mw of 8·105 kDa with a low polydispersity index, i.e. 1.4. This work showed how by optimizing acidic fermn. it could be possible to get a large amt. of OA from OFMSW to be then transformed into PHA. This step is important as it greatly affects the total final PHA yield. Data obtained in this work can be useful as the starting point for considering the economic feasibility of PHA prodn. from OFMSW by using mixed culture.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXitV2nsb7N&md5=3c5295c849bc49d91e474aebcd6fc8a2
16
Basset, N.; Katsou, E.; Frison, N.; Malamis, S.; Dosta, J.; Fatone, F. Integrating the selection of PHA storing biomass and nitrogen removal via nitrite in the main wastewater treatment line. Bioresour. Technol. 2016, 200, 820– 829, DOI: 10.1016/j.biortech.2015.10.063
Google Scholar
16
Integrating the selection of PHA storing biomass and nitrogen removal via nitrite in the main wastewater treatment line
Basset, N.; Katsou, E.; Frison, N.; Malamis, S.; Dosta, J.; Fatone, F.
Bioresource Technology (2016), 200 (), 820-829CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
A novel scheme was developed for the treatment of municipal wastewater integrating nitritation/denitritation with the selection of polyhydroxyalkanoates (PHA) storing biomass under an aerobic/anoxic, feast/famine regime. The process took place in a sequencing batch reactor (SBR) and the subsequent PHA accumulation in a batch reactor. The carbon source added during the selection and accumulation steps consisted of fermn. liq. from the org. fraction of municipal solids waste (OFMSW FL) (Period I) and OFMSW and primary sludge fermn. liq. (Period II). Selection of PHA storing biomass was successful and denitritation was driven by internally stored PHA during the famine phase. Under optimum conditions of SBR operation ammonia removal was 93%, reaching a max. nitrite removal of 98%. The treated effluent met the nitrogen limits, while PHA-storing biomass was successfully selected. The max. accumulation of PHA was 10.6% (wt.) since the nutrients present in the carbon source promoted bacterial growth.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhslegu7vI&md5=67bcf3d5afa2fbe454c2f19785c77c0e
17
Valentino, F.; Morgan-Sagastume, F.; Fraraccio, S.; Corsi, G.; Zanaroli, G.; Werker, A.; Majone, M. Sludge minimization in municipal wastewater treatment by polyhydroxyalkanoate (PHA) production. Environ. Sci. Pollut. Res. 2015, 22, 7281– 7294, DOI: 10.1007/s11356-014-3268-y
Google Scholar
17
Sludge minimization in municipal wastewater treatment by polyhydroxyalkanoate (PHA) production
Valentino, Francesco; Morgan-Sagastume, Fernando; Fraraccio, Serena; Corsi, Giovanna; Zanaroli, Giulio; Werker, Alan; Majone, Mauro
Environmental Science and Pollution Research (2015), 22 (10), 7281-7294CODEN: ESPLEC; ISSN:0944-1344. (Springer)
An innovative approach has been recently proposed in order to link polyhydroxyalkanoates (PHA) prodn. with sludge minimization in municipal wastewater treatment, where (1) a sequencing batch reactor (SBR) is used for the simultaneous municipal wastewater treatment and the selection/enrichment of biomass with storage ability and (2) the acidogenic fermn. of the primary sludge is used to produce a stream rich in volatile fatty acids (VFAs) as the carbon source for the following PHA accumulation stage. The reliability of the proposed process has been evaluated at lab scale by using substrate synthetic mixts. for both stages, simulating a low-strength municipal wastewater and the effluent from primary sludge fermn., resp. Six SBR runs were performed under the same operating conditions, each time starting from a new activated sludge inoculum. In every SBR run, despite the low VFA content (10 % COD, COD basis) of the substrate synthetic mixt., a stable feast-famine regime was established, ensuring the necessary selection/enrichment of the sludge and sol. COD removal to 89 %. A good process reproducibility was obsd., as also confirmed by denaturing gradient gel electrophoresis (DGGE) anal. of the microbial community, which showed that a high similarity after SBR steady-state had been reached. The main variation factors of the storage properties among different runs were uncontrolled changes of settling properties which in turn caused variations of both sludge retention time and specific org. loading rate. In the following accumulation batch tests, the selected/enriched consortium was able to accumulate PHA with good rate (63 mg CODPHA g CODXa-1 h-1) and yield (0.23 CODPHA CODΔS-1) in spite that the feeding soln. was different from the acclimation one. Even though the PHA prodn. performance still requires optimization, the proposed process has a good potential esp. if coupled to minimization of both primary sludge (by its use as the VFA source for the PHA accumulation, via previous fermn.) and excess secondary sludge (by its use as the biomass source for the PHA accumulation).
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhtFeru7vE&md5=c51d7526f28c36bea36f353e25c46c5c
18
Valentino, F.; Beccari, M.; Fraraccio, S.; Zanaroli, G.; Majone, M. Feed frequency in a Sequencing Batch Reactor strongly affects the production of polyhydroxyalkanoates (PHAs) from volatile fatty acids. New Biotechnol. 2014, 31, 264– 275, DOI: 10.1016/j.nbt.2013.10.006
Google Scholar
18
Feed frequency in a sequencing batch reactor strongly affects the production of polyhydroxyalkanoates (PHAs) from volatile fatty acids
Valentino, Francesco; Beccari, Mario; Fraraccio, Serena; Zanaroli, Giulio; Majone, Mauro
New Biotechnology (2014), 31 (4), 264-275CODEN: NBEIBR; ISSN:1871-6784. (Elsevier B.V.)
The prodn. of polyhydroxyalkanoates (PHAs) by activated sludge selected in a sequencing batch reactor (SBR) has been investigated. Several SBR runs were performed at the same applied org. load rate (OLR), hydraulic retention time (HRT) and feed concn. (8.5 g COD L-1 of volatile fatty acids, VFAs) under aerobic conditions. The effect of the feeding time was only evaluated with a cycle length of 8 h; for this particular cycle length, an increase in the storage response was obsd. by increasing the rate at which the substrate was fed into the reactor (at a fixed feeding frequency). Furthermore, a significantly stronger effect was obsd. by decreasing the cycle length from 8 h to 6 h and then to 2 h, changing the feed frequency or changing the org. load given per cycle (all of the other conditions remained the same): the length of the feast phase decreased from 26 to 20.0 and then to 19.7% of the overall cycle length, resp., due to an increase in the substrate removal rate. This removal rate was high and similar for the runs with cycle lengths of 2 h and 6 h in the SBR. This result was due to an increase in the selective pressure and the specific storage properties of the selected biomass. The highest polymer productivity after long-term accumulation batch tests was 1.7 g PHA L-1 d-1, with PHA content in the biomass of approx. 50% on a COD basis under nitrogen limitation. The DGGE profiles showed that the good storage performance correlated to the development of Lampropedia hyalina, which was only obsd. in the SBR runs characterized by a shorter cycle length.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXhsl2gsrvJ&md5=bde6cdacea0a7bb083c1e9908b21f9fd
19
Standard Methods for the Examination of Water and Wastewater, 20th ed.; American Public Health Association, 1998.
Google Scholar
There is no corresponding record for this reference.
20
Braunegg, G.; Sonnleitner, B.; Lafferty, R. M. A. Rapid gas chromatographic method for the determination of poly-b-hydroxybutyric acid in microbial biomass. Eur. J. Appl. Microbiol. 1978, 6, 29– 37, DOI: 10.1007/BF00500854
Google Scholar
20
A rapid gas chromatographic method for the determination of poly-β-hydroxybutyric acid in microbial biomass
Braunegg, G.; Sonnleitner, B.; Lafferty, R. M.
European Journal of Applied Microbiology and Biotechnology (1978), 6 (1), 29-37CODEN: EJABDD; ISSN:0340-2118.
The gas chromatog. method for the detn. of poly-β-hydroxybutyric acid (PHB) [26063-00-3] consists of a mild acid or alk. methanolysis of poly-β-hydroxybutyric acid directly without previous extn. of PHB from the cells; this is followed by gas chromatog. of the 3-hydroxybutyric acid Me ester. The method is characterized by high accuracy and excellent reproducibility, permitting detns. as low as 10-5 g/L. Only 4 h is required from sampling from the fermentor till completion of the PHB detn.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE1MXosFWruw%253D%253D&md5=db9baae8c3e1888aca113cb5cfdd0a2d
21
Valentino, F.; Brusca, A. A.; Beccari, M.; Nuzzo, A.; Zanaroli, G.; Majone, M. Start up of biological sequencing batch reactor (SBR) and short-term biomass acclimation for polyhydroxyalkanoates production. J. Chem. Technol. Biotechnol. 2013, 88, 261– 270, DOI: 10.1002/jctb.3824
Google Scholar
21
Start up of biological sequencing batch reactor (SBR) and short-term biomass acclimation for polyhydroxyalkanoates production
Valentino, Francesco; Brusca, Angelo Antonio; Beccari, Mario; Nuzzo, Andrea; Zanaroli, Giulio; Majone, Mauro
Journal of Chemical Technology and Biotechnology (2013), 88 (2), 261-270CODEN: JCTBED; ISSN:0268-2575. (John Wiley & Sons Ltd.)
The adaptation/selection of mixed microbial cultures under feast/famine conditions is an essential step for polyhydroxyalkanoates (PHA) prodn. This study investigated the short-term adaptation of a mixed microbial culture (activated sludge) during the start up of a sequencing batch reactor (SBR). Four different SBR runs were performed starting from different inocula and operated at the same org. load rate (8.5 gCOD L-1 d-1) and hydraulic retention time (1 day). At 3-7 days from SBR start up, the selected biomass was able to store PHA at comparable rate and yield with those obtained after long-term acclimation. Independently from the time passed, a short feast phase was the key parameter to obtain PHA storage at high rate and yield in the following accumulation stage (244 mgCOD g-1CODnonPolym h-1 for specific storage rate and 48% COD COD-1 as PHA content in the biomass). The DGGE profiles showed that the good storage performance and the structure of the microbial community were not fully correlated. CONCLUSIONS: The results suggest a new strategy for operating the PHA accumulation stage directly in the SBR, after very short biomass adaptation, instead of using two sep. reactors for biomass enrichment and PHA accumulation, resp. Copyright © 2012 Society of Chem. Industry.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmslKlt7Y%253D&md5=40a192b1ba88f4e94a1edcc60a524d65
22
Hao, J.; Wang, H. Volatile fatty acids productions by mesophilic and thermophilic sludge fermentation: Biological responses to fermentation temperature. Bioresour. Technol. 2015, 175, 367– 373, DOI: 10.1016/j.biortech.2014.10.106
Google Scholar
22
Volatile fatty acids productions by mesophilic and thermophilic sludge fermentation: Biological responses to fermentation temperature
Hao, Jiuxiao; Wang, Hui
Bioresource Technology (2015), 175 (), 367-373CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
The volatile fatty acids (VFAs) productions, as well as hydrolases activities, microbial communities, and homoacetogens, of mesophilic and thermophilic sludge anaerobic fermn. were investigated to reveal the microbial responses to different fermn. temps. Thermophilic fermn. led to 10-fold more accumulation of VFAs compared to mesophilic fermn. α-glucosidase and protease had much higher activities in thermophilic reactor, esp. protease. Illumina sequencing manifested that raising fermn. temp. increased the abundances of Clostridiaceae, Microthrixaceae and Thermotogaceae, which could facilitate either hydrolysis or acidification. Real-time PCR anal. demonstrated that under thermophilic condition the relative abundance of homoacetogens increased in batch tests and reached higher level at stable fermn., whereas under mesophilic condition it only increased slightly in batch tests. Therefore, higher fermn. temp. increased the activities of key hydrolases, raised the proportions of bacteria involved in hydrolysis and acidification, and promoted the relative abundance of homoacetogens, which all resulted in higher VFAs prodn.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhvVGgur3M&md5=2d352c6299cbaac265cf3b3607812394
23
Girotto, F.; Lavagnolo, M. C.; Pivato, A.; Cossu, R. Acidogenic fermentation of the organic fraction of municipal solid waste and cheese whey for bio-plastic precursors recovery – Effects of process conditions during batch tests. Waste Manage. 2017, 70, 71– 80, DOI: 10.1016/j.wasman.2017.09.015
Google Scholar
23
Acidogenic fermentation of the organic fraction of municipal solid waste and cheese whey for bio-plastic precursors recovery - Effects of process conditions during batch tests
Girotto, Francesca; Lavagnolo, Maria Cristina; Pivato, Alberto; Cossu, Raffaello
Waste Management (Oxford, United Kingdom) (2017), 70 (), 71-80CODEN: WAMAE2; ISSN:0956-053X. (Elsevier Ltd.)
The problem of fossil fuels dependency is being addressed through sustainable bio-fuels and bio-products prodn. worldwide. At the base of this bio-based economy there is the efficient use of biomass as non-virgin feedstock. Through acidogenic fermn., org. waste can be valorised in order to obtain several precursors to be used for bio-plastic prodn. Some investigations have been done but there is still a lack of knowledge that must be filled before moving to effective full scale plants. Acidogenic fermn. batch tests were performed using food waste (FW) and cheese whey (CW) as substrates. Effects of nine different combinations of substrate to inoculum (S/I) ratio (2, 4, and 6) and initial pH (5, 7, and 9) were investigated for metabolites (acetate, butyrate, propionate, valerate, lactate, and ethanol) productions. Results showed that the most abundant metabolites deriving from FW fermn. were butyrate and acetate, mainly influenced by the S/I ratio (acetate and butyrate max. productions of 21.4 and 34.5 g/L, resp., at S/I = 6). Instead, when dealing with CW, lactate was the dominant metabolite significantly correlated with pH (lactate max. prodn. of 15.7 g/L at pH = 9).
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFGgtbbL&md5=d14ba64e05f69b36cf2e3684f151911b
24
Bolzonella, D.; Fatone, F.; Pavan, P.; Cecchi, F. Anaerobic fermentation of organic fraction of municipal solid waste for the production of soluble organic compounds. Ind. Eng. Chem. Res. 2005, 44, 3412– 3418, DOI: 10.1021/ie048937m
Google Scholar
24
Anaerobic Fermentation of Organic Municipal Solid Wastes for the Production of Soluble Organic Compounds
Bolzonella, David; Fatone, Francesco; Pavan, Paolo; Cecchi, Franco
Industrial & Engineering Chemistry Research (2005), 44 (10), 3412-3418CODEN: IECRED; ISSN:0888-5885. (American Chemical Society)
After investigating the application of the mesophilic and thermophilic processes in completely stirred, batch, and plug-flow reactors, in this study the authors consider the anaerobic fermn. of source-sorted org. municipal solid wastes in psychrophilic conditions (14-22°) without pH control. The pilot-scale reactor was operated in a batch mode, with a hydraulic retention time of 4-4.5 d. The prodn. of sol. COD from the particulate matter was (on av.) 0.27 g COD per g of total volatile solids fed to the reactor when operating with a total solids content of 20-35 g/L. The volatile fatty acids (VFA) were 15% of the sol. COD produced after 4 d of reaction. These values are far lower than those found in mesophilic and thermophilic conditions, where the prodn. of sol. COD ranged from 0.5 up to 0.9 g COD/g TVSfed and volatile fatty acids could reach 90% of sol. COD. Further, the first-order reaction const. for the hydrolysis process, Kh, for the psychrophilic conditions was found equal to 0.11 d-1 at 20°, while it was in the range 0.2-0.4 d-1 when operating in mesophilic or thermophilic conditions. Conclusively, the study of the psychrophilic fermn. process allowed for completing the scenario of different options of anaerobic solid-state fermn. of org. waste. Though mesophilic and thermophilic processes resulted in being more effective in dissoln. of particulate matter, psychrophilic processes can be of some interest because they are simpler and energy saving. In particular, psychrophilic processes can be useful for the prodn. of rough sol. COD to be used, e.g., for sustaining the biol. nutrients removal processes in wastewater treatment.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXis1OgsLg%253D&md5=960c634b2349a290bc3defbadb22a4a6
25
Bengtsson, S.; Pisco, A. R.; Johansson, P.; Lemos, P. C.; Reis, M. A. M. Molecular weight and thermal properties of polyhydroxyalkanoates produced from fermented sugar molasses by open mixed cultures. J. Biotechnol. 2010, 147, 172– 179, DOI: 10.1016/j.jbiotec.2010.03.022
Google Scholar
25
Molecular weight and thermal properties of polyhydroxyalkanoates produced from fermented sugar molasses by open mixed cultures
Bengtsson, Simon; Pisco, Ana R.; Johansson, Peter; Lemos, Paulo C.; Reis, Maria A. M.
Journal of Biotechnology (2010), 147 (3-4), 172-179CODEN: JBITD4; ISSN:0168-1656. (Elsevier B.V.)
Polyhydroxyalkanoates (PHAs) produced from fermented molasses and synthetic feeds contg. single volatile fatty acids (VFAs) by an open mixed culture enriched in glycogen accumulating organisms (GAOs) were characterized with regards to mol. wt. and thermal properties. The polymer contained five types of monomers, namely 3-hydroxybutyrate, 3-hydroxy-2-methylbutyrate, 3-hydroxyvalerate, 3-hydroxy-2-methylvalerate and 3-hydroxyhexanoate in different ratios depending on the VFA compn. of the substrate. Polymers produced from fermented molasses had wt. av. mol. wts. (Mw) in the range (3.5-4.3) × 105 g/mol and polydispersity indexes (PDI) of 1.8-2.1 while polymers produced from synthetic VFAs had Mw of (4.5-9.0) × 105 g/mol and PDI of 1.7-3.9. Thermal properties such as glass transition temp. (-14 °C to 4.8 °C), melting temp. (89-174 °C) and melting enthalpy (0-82.1 J/g) were controlled in broad ranges by the monomer compn. The decompn. temps. of the polymers produced were between 277.2 °C and 294.9 °C, and independent of monomer compn. and mol. wt.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXntVemu7o%253D&md5=ca4dc0cfef36e81a81ee31a666fe4c4f
26
Pittmann, T.; Steinmetz, H. Polyhydroxyalkanoate production on waste water treatment plants: process scheme, operating conditions and potential analysis for german and european municipal waste water treatment plants. Bioengineering 2017, 4, 54, DOI: 10.3390/bioengineering4020054
Google Scholar
There is no corresponding record for this reference.
27
Campanari, S.; e Silva, F. A.; Bertin, L.; Villano, M.; Majone, M. Effect of the organic loading rate on the production of polyhydroxyalkanoates in a multi-stage process aimed at the valorization of olive oil mill wastewater. Int. J. Biol. Macromol. 2014, 71, 34– 41, DOI: 10.1016/j.ijbiomac.2014.06.006
Google Scholar
27
Effect of the organic loading rate on the production of polyhydroxyalkanoates in a multi-stage process aimed at the valorization of olive oil mill wastewater
Campanari, Sabrina; e Silva, Francisca A.; Bertin, Lorenzo; Villano, Marianna; Majone, Mauro
International Journal of Biological Macromolecules (2014), 71 (), 34-41CODEN: IJBMDR; ISSN:0141-8130. (Elsevier B.V.)
Mixed microbial culture polyhydroxyalkanoates (PHA) prodn. has been investigated by using olive oil mill wastewater (OMW) as no-cost feedstock in a multi-stage process, also involving phenols removal and recovery. The selection of PHA-storing microorganisms occurred in a sequencing batch reactor (SBR), fed with dephenolized and fermented OMW and operated at different org. loading rates (OLR), ranging from 2.40 to 8.40 gCOD/L d. The optimal operating condition was obsd. at an OLR of 4.70 gCOD/L d, which showed the highest values of storage rate and yield (339 ± 48 mgCOD/gCOD h and 0.56 ± 0.05 COD/COD, resp.). The OLR applied to the SBR largely affected the performance of the PHA-accumulating reactor, which was fed through multiple pulsed addns. of pretreated OMW. From an overall mass balance, involving all the stages of the process, an abatement of about 85% of the OMW initial COD (COD) was estd. whereas the conversion of the influent COD into PHA was about 10% (or 22% by taking into account only the COD contained in the pretreated OMW, which is directly fed to the PHA prodn. stages). Overall, polymer volumetric productivity (calcd. from the combination of both the SBR and the accumulation reactor) accounted for 1.50 gPHA/L d.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXht1ags73N&md5=ff144388feec0f5a9c28bdef58724e83
28
Dionisi, D.; Majone, M.; Papa, V.; Beccari, M. Biodegradable polymers from organic acids by using activated sludge enriched by aerobic periodic feeding. Biotechnol. Bioeng. 2004, 85, 569– 579, DOI: 10.1002/bit.10910
Google Scholar
28
Biodegradable polymers from organic acids by using activated sludge enriched by aerobic periodic feeding
Dionisi, Davide; Majone, Mauro; Papa, Viviana; Beccari, Mario
Biotechnology and Bioengineering (2004), 85 (6), 569-579CODEN: BIBIAU; ISSN:0006-3592. (John Wiley & Sons, Inc.)
This article describes a process for the prodn. of biopolymers (polyhydroxyalkanoates, PHAs) based on the aerobic enrichment of activated sludge to obtain mixed cultures able to store PHAs at high rates and yields. Enrichment was obtained through the selective pressure established by feeding the C source in a periodic mode (feast and famine regime) in a sequencing batch reactor. A concd. mixt. of acetic, lactic, and propionic acids (overall concn. of 8.5 g COD/L) was fed every 2 h at 1/day overall diln. rate. Even at such high org. load (8.5 g COD/L-day), the selective pressure due to periodic feeding was effective in obtaining a biomass with a storage ability much higher than activated sludges. The immediate biomass response to substrate excess (as detd. thorough short-term batch tests) was characterized by a storage rate and yield of 649 mg PHA (as COD) g biomass (as COD)-1 h-1 and 0.45 mg PHA (as COD) mg removed substrates (as COD-1), resp. When the substrate excess was present for >2 h (long-term batch tests), the storage rate and yield decreased, whereas growth rate and yield significantly increased due to biomass adaptation. A max. polymer fraction in the biomass was therefore obtained at ∼50% (on COD basis). As for the PHA compn., the copolymer poly(β-hydroxybutyrate/β-hydroxyvalerate) with 31% of hydroxyvalerate monomer was produced from the substrate mixt. Comparison of the tests with individual and mixed substrates seemed to indicate that, on removing the substrate mixt. for copolymer prodn., propionic acid was fully utilized to produce propionylCoA, whereas the acetylCoA was fully provided by acetic and lactic acid.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXhvFektrg%253D&md5=78541ffc37180f2db21541d656329af1
29
Albuquerque, M. G. E.; Torres, C. A. V.; Reis, M. A. M. Polyhydroxyalkanoates (PHA) production by a mixed microbial culture using sugar molasses: effect of the influent substrate concentration on culture selection. Water Res. 2010, 44, 3419– 3433, DOI: 10.1016/j.watres.2010.03.021
Google Scholar
29
Polyhydroxyalkanoate (PHA) production by a mixed microbial culture using sugar molasses: Effect of the influent substrate concentration on culture selection
Albuquerque, M. G. E.; Torres, C. A. V.; Reis, M. A. M.
Water Research (2010), 44 (11), 3419-3433CODEN: WATRAG; ISSN:0043-1354. (Elsevier B.V.)
In Polyhydroxyalkanoate (PHA) prodn. processes using Mixed Microbial Culture (MMC), the success of the culture selection step dets., to a great extent, the PHA accumulation performance obtained in the final PHA prodn. stage. In this study, the effect of the influent substrate concn. (30-60 Cmmol VFA/L) on the selection of a PHA-storing culture using a complex feedstock, fermented sugar molasses, was assessed. At 30 and 45 Cmmol VFA/L, substrate concn. impacted on the process kinetics through a substrate dependent kinetic limitation effect. However, further increasing the carbon substrate concn. to 60 Cmmol VFA/L, resulted in an unforeseen growth limitation effect assocd. with a micronutrient deficiency of the fermented feedstock (magnesium) and high operating pH. Struvite pptn. caused a nutrient limitation which prevented biomass concn. increase, thus causing the feast to famine length ratio to vary in the selection reactor, with subsequent impact on the selective pressure for PHA-storing organisms. A highly dynamic response of the selected population to transient conditions of feast to famine ratio, in the range of 0.21-1.1, was obsd. Kinetic (limiting concn. of carbon source) and physiol. (loss of internal growth limitation due to the shorter length of famine phase) effects, resulting from variation of the influent substrate concn., were subsequently demonstrated in batch studies. The culture selected at an influent substrate concn. of 45 Cmmol VFA/L showed the best PHA-storing capacity since neither substrate concn. nor feast to famine ratio were limiting factors. This culture, highly enriched in PHA-storing organisms (88%), reached a max. PHA content of 74.6%.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXmtlKhur8%253D&md5=6a686a80ffaafb558c056f4ccd234949
30
Majone, M.; Massanisso, P.; Carucci, A.; Lindrea, K.; Tandoi, V. Influence of storage on kinetic selection to control aerobic filamentous bulking. Water Sci. Technol. 1996, 34, 223– 232, DOI: 10.2166/wst.1996.0554
Google Scholar
30
Influence of storage on kinetic selection to control aerobic filamentous bulking
Majone, M.; Massanisso, P.; Carucci, A.; Lindrea, K.; Tandoi, V.
Water Science and Technology (1996), 34 (5-6, Water Quality International '96, Part 3), 223-232CODEN: WSTED4; ISSN:0273-1223. (Elsevier)
In various activated sludge systems, sludge grows under transient (unbalanced) conditions and storage of internal polymers becomes important. Differences in storage capacity under transients are often used to explain kinetic control of bulking, but storage is neither studied in detail nor usually included in modeling. For this reason, the transient response of different aerobic mixed cultures was studied by exptl. detg. the role of storage. Two different mixed cultures (bulking and non-bulking) were selected in an acetate-limited medium, by continuous or intermittent feeding of a CSTR, resp. Batch tests were used to investigate the transient response of the selected cultures as a function of the starvation time and of the ratio of the initial concn. of the substrate and sludge biomass (So/Xo). In most exptl. conditions, both cultures showed that the storage of polyhydroxybutyrate (PHB) is in general the prevailing mechanism of substrate removal. In particular, the culture dominated by floc-formers showed very fast response to the substrate spike with a high obsd. yield. Storage was practically the only metab. occurring. The ratio So/Xo did not have a major role in detg. the type and extent of the response. Starvation did not affect the response of the floc-formers to transient conditions. For the filamentous bacteria, both the growth response and, even more significantly, the storage response were neg. affected. Hence, the difference in storage capacity between filamentous and floc-forming bacteria was further increased.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK28XnsFOrsLs%253D&md5=fd6c600d855da23ef031310fbb0e94a7
31
Albuquerque, M. G. E.; Eiroa, M.; Torres, C.; Nunes, B. R.; Reis, M. A. M. Strategies for the development of a side stream process for polyhydroxyalkanoate (PHA) production from sugar cane molasses. J. Biotechnol. 2007, 130, 411– 421, DOI: 10.1016/j.jbiotec.2007.05.011
Google Scholar
31
Strategies for the development of a side stream process for polyhydroxyalkanoate (PHA) production from sugar cane molasses
Albuquerque, M. G. E.; Eiroa, M.; Torres, C.; Nunes, B. R.; Reis, M. A. M.
Journal of Biotechnology (2007), 130 (4), 411-421CODEN: JBITD4; ISSN:0168-1656. (Elsevier B.V.)
A three-stage process was developed to produce polyhydroxyalkanoates (PHAs) from sugar cane molasses. The process includes (1) molasses acidogenic fermn., (2) selection of PHA-accumulating cultures, (3) PHA batch accumulation using the enriched sludge and fermented molasses. In the fermn. step, the effect of pH (5-7) on the org. acids profile and productivity was evaluated. At higher pH, acetic and propionic acids were the main products, while lower pH favored the prodn. of butyric and valeric acids. PHA accumulation using fermented molasses was evaluated with two cultures selected either with acetate or fermented molasses. The effect of org. acids distribution on polymer compn. and yield was evaluated with the acetate selected culture. Storage yields varied from 0.37 to 0.50 Cmmol HA/Cmmol VFA. A direct relationship between the type of org. acids used and the polymers compn. was obsd. Low ammonia concn. (0.1 Nmmol/l) in the fermented molasses stimulated PHA storage (0.62 Cmmol HA/Cmmol VFA). In addn., strategies of reactor operation to select a PHA-accumulating culture on fermented molasses were developed. The combination of low org. loading with high ammonia concn. selected a culture with a stable storage capacity and with a storage yield (0.59 Cmmol HA/Cmmol VFA) similar to that of the acetate-selected culture.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXnsFKgsb0%253D&md5=eb8c5b8ee714eacc8f3d7979c5ff9f8a
32
Valentino, F.; Karabegovic, L.; Majone, M.; Morgan-Sagastume, F.; Werker, A. Polyhydroxyalkanoate (PHA) storage within a mixed-culture biomass with simultaneous growth as a function of accumulation substrate nitrogen and phosphorus levels. Water Res. 2015, 77, 49– 63, DOI: 10.1016/j.watres.2015.03.016
Google Scholar
32
Polyhydroxyalkanoate (PHA) storage within a mixed-culture biomass with simultaneous growth as a function of accumulation substrate nitrogen and phosphorus levels
Valentino, Francesco; Karabegovic, Lamija; Majone, Mauro; Morgan-Sagastume, Fernando; Werker, Alan
Water Research (2015), 77 (), 49-63CODEN: WATRAG; ISSN:0043-1354. (Elsevier Ltd.)
The response of a mixed-microbial-culture (MMC) biomass for PHA accumulation was evaluated over a range of relative nitrogen (N) and phosphorus (P) availabilities with respect to the supply of either complex (fermented whey permeate - FWP) or simpler (acetic acid) org. feedstocks. Fed-batch feed-on-demand PHA accumulation expts. were conducted where the feed N/COD and P/COD ratios were varied ranging from conditions of nutrient starvation to excess. A feast-famine enrichment (activated sludge) biomass, produced in a pilot-scale aerobic sequencing batch reactor on FWP and with a long history of stable PHA accumulation performance, was used for all the expts. as ref. material. FWP with N/COD ratios of (2, 5, 15, 70 mg/g all with P/COD = 8 mg/g) as well as simulated FWP with nutrient starvation (N/COD = P/COD = 0) conditions were applied. For the acetic acid accumulations, nutrient starvation as well as N/COD variations (2.5, 5, 50 mg/g all with P/COD = 9 mg/g) and P/COD variations (0.5, 2, 9, 15 mg/g all with N/COD = 10 mg/g) were evaluated. An optimal range of combined N and P limitation with N/COD from 2 to 15 mg/g and P/COD from 0.5 to 3 mg/g was considered to offer consistent improvement of productivity over the case of nutrient starvation. Productivity increased due to active biomass growth of the PHA storing biomass without obsd. risk for a growth response overtaking PHA storage activity. PHA prodn. with respect to the initial active biomass was significantly higher even in cases of excess nutrient addns. when compared to the cases of nutrient starvation. The 24-h PHA productivities were enhanced as much as 4-fold from a base value of 1.35 g-PHA per g initial active biomass with respect nutrient starvation feedstock. With or without nutrient loading the biomass consistently accumulated similar and significant PHA (nominally 60% g-PHA/g-VSS). Based on results from replicate expts. some variability in the extant biomass max. PHA content was attributed to interpreted differences in the biomass initial physiol. state and not due to changes in feedstock nutrient loading. We found that the accumulation process prodn. rates for mixed cultures can be sustained long after the max. PHA content of the biomass was reached. Within the specific context of the applied fed-batch feed-on-demand methods, active biomass growth was interpreted to have been largely restricted to the PHA-storing phenotypic fraction of the biomass. This study suggests practical prospects for mixed culture PHA prodn. using a wide range of volatile fatty acid (VFA) rich feedstocks. Such VFA sources derived from residual industrial or municipal org. wastes often naturally contain assocd. nutrients ranging in levels from limitation to excess.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXlsFeqsbw%253D&md5=48c1b6127e1a67e236ed39bc9c9222a9
33
Morgan-Sagastume, F.; Valentino, F.; Hjort, M.; Zanaroli, G.; Majone, M.; Werker, A. Acclimation process for enhancing polyhydroxyalkanoate accumulation in activated-sludge biomass. Waste Biomass Valorization 2019, 10, 1065– 1082, DOI: 10.1007/s12649-017-0122-8
Google Scholar
33
Acclimation Process for Enhancing Polyhydroxyalkanoate Accumulation in Activated-Sludge Biomass
Morgan-Sagastume, Fernando; Valentino, Francesco; Hjort, Markus; Zanaroli, Giulio; Majone, Mauro; Werker, Alan
Waste and Biomass Valorization (2019), 10 (4), 1065-1082CODEN: WBVAAG; ISSN:1877-2641. (Springer)
A strategy was evaluated for conditioning activated sludge biomass to a new substrate whereby the polyhydroxyalkanoate (PHA) accumulation capacity of the biomass was enhanced based on a series of aerobic feast-famine acclimation cycles applied prior to PHA accumulation. Different biomass types enriched during the treatment of municipal wastewater at lab., pilot, and full scales were exposed to aerobic feast-famine acclimation cycles at different feast-to-famine ratios with an acetate-propionate mixt. (lab. scale), acetate (pilot scale), and fermented waste-sludge centrate (pilot scale). A sevenfold increase in specific PHA storage rates and 20% increase in substrate utilization rates were obsd. during acclimation cycles (lab. acetate-propionate). Biomass acclimation led to more than doubling of the specific substrate utilization rates, PHA storage rates, biomass PHA contents, and specific PHA productivities (per initial biomass) during PHA accumulation. The biomass PHA contents were found to increase due to acclimation from 0.19 to 0.34 (lab. acetate-propionate), 0.39 to 0.46 (pilot acetate) and 0.19 to 0.25 gPHA/gVSS (pilot centrate). A similar bacterial community structure during acclimation indicated that a physiol. rather than a genotypic adaptation occurred in the biomass. The physiol. state of the biomass at the start of PHA accumulation was deemed significant in the subsequent PHA-accumulation performance. Pos. acclimation trends can be monitored by measuring the relative increase in feast substrate utilization or respiration rates with respect to those of the first acclimation cycle.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsl2murvE&md5=56c42a11f8f6bbda1ba157abb55a0969
34
Amulya, K.; Jukuri, S.; Venkata Mohan, S. Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling. Bioresour. Technol. 2015, 188, 231– 239, DOI: 10.1016/j.biortech.2015.01.070
Google Scholar
34
Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling
Amulya, K.; Jukuri, Srinivas; Venkata Mohan, S.
Bioresource Technology (2015), 188 (), 231-239CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
Polyhydroxyalkanoates (PHA) prodn. was evaluated in a multistage operation using food waste as a renewable feedstock. The first step involved the prodn. of bio-hydrogen (bio-H2) via acidogenic fermn. Volatile fatty acid (VFA) rich effluent from bio-H2 reactor was subsequently used for PHA prodn., which was carried out in two stages, Stage II (culture enrichment) and Stage III (PHA prodn.). PHA-storing microorganisms were enriched in a sequencing batch reactor (SBR), operated at two different cycle lengths (CL-24; CL-12). Higher polymer recovery as well as VFA removal was achieved in CL-12 operation both in Stage II (16.3% dry cell wt. (DCW); VFA removal, 84%) and Stage III (23.7% DCW; VFA removal, 88%). The PHA obtained was a co-polymer [P(3HB-co-3HV)] of PHB and PHV. The results obtained indicate that this integrated multistage process offers new opportunities to further leverage large scale PHA prodn. with simultaneous waste remediation in the framework of biorefinery.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhvVCjtro%253D&md5=782d175b055534d6dd451623826729df
35
Moretto, G., Ardolino, F., Piasentin, A., Girotto, L., Cecchi, F. Integrated anaerobic codigestion system for the organic fraction of municipal solid waste and sewage sludge treatment: an Italian case study. J. Chem. Technol. Biotechnol. 2019, DOI: 10.1002/jctb.5993 .
Google Scholar
There is no corresponding record for this reference.
36
Valentino, F.; Moretto, G.; Gottardo, M.; Pavan, P.; Bolzonella, D.; Majone, M. Novel routes for urban bio-waste management: A combined acidic fermentation and anaerobic digestion process for platform chemicals and biogas production. J. Cleaner Prod. 2019, 220, 368– 375, DOI: 10.1016/j.jclepro.2019.02.102
Google Scholar
36
Novel routes for urban bio-waste management: A combined acidic fermentation and anaerobic digestion process for platform chemicals and biogas production
Valentino, Francesco; Moretto, Giulia; Gottardo, Marco; Pavan, Paolo; Bolzonella, David; Majone, Mauro
Journal of Cleaner Production (2019), 220 (), 368-375CODEN: JCROE8; ISSN:0959-6526. (Elsevier Ltd.)
A combined acidic fermn. and anaerobic digestion (AD) treatment has been developed on pilot scale for urban bio-waste conversion into volatile fatty acid (VFA) and biogas. The specific waste mixt. was composed by the pre-treated org. fraction of municipal solid waste (OFMSW) and waste activated sludge (WAS), both produced inside the Treviso (northeast Italy) municipality. The effect of temp. (37 °C and 55 °C) was investigated in both steps. Only the mesophilic fermn. process provided a VFA-rich stream (19.5 g CODVFA/L) with stable phys.-chem. features, with no need of chems. addn. for pH control. The sludge buffering capacity made this step tech. feasible. The AD step was performed on the solid-rich fraction of fermented bio-waste, after diln. with excess WAS. No relevant differences were obsd. under the two investigated temp.: in the steady state (org. loading rate of 2.5 kg VS/m3 d), the specific biogas prodn. was 0.40 and 0.45 m3/kg VS at 37 °C and 55 °C resp., with similar CH4 content (63-64% vol./vol.). The scaled-up version of the system (in an av. urban municipality of 170,000 Person Equiv.) revealed that the whole process is thermally sustainable if both reactors are operated at mesophilic temp.: 36% of surplus thermal energy and 13,03 MWh/d of produced electricity, which corresponds to a revenue of 609,605 euro/yr. In addn., 2,262 kg CODVFA/d are available for parallel purposes, such as the synthesis of bio-products with higher added value than bio-methane (e.g. biopolymers).
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXjs1Oqt78%253D&md5=92be45b65b4d98da3577900ccb2c3e2c

Cited By

Click to copy section linkSection link copied!

Explore this article's citation statements on scite.ai

This article is cited by 115 publications.

Gaia Salvatori, Angela Marchetti, Anna Maria Russo, Jesus Rodriguez, Vadim Scerbacov, Francesco Fianelli, Sara Alfano, Simona Crognale, Alessio Massimi, Simona Rossetti, Giacomo Canali, Tiziana De Micheli, David Bolzonella, Marianna Villano. Pilot-Scale Acidogenic Fermentation of Reground Pasta Byproduct for Polyhydroxyalkanoate Production with Mixed Microbial Cultures. ACS Sustainable Chemistry & Engineering 2025, 13 (8) , 3024-3035. https://doi.org/10.1021/acssuschemeng.4c03754
Tijo Cherian Karthika Rajendran Beena Cherian Shibin Eranhottu Fahmeeda Parveen Panikkaveetil Shahulhameed . Transformation of Biochar for Removal of Noxious Contaminants from Industrial Effluents: A Green Technology for Sustainable Future. , 247-263. https://doi.org/10.1021/bk-2024-1478.ch011
Gaia Salvatori, Sara Alfano, Andrea Martinelli, Marco Gottardo, Marianna Villano, Bruno S. Ferreira, Francesco Valentino, Laura Lorini. Chlorine-free Extractions of Mixed-Culture Polyhydroxyalkanoates Produced from Fermented Sewage Sludge at Pilot Scale. Industrial & Engineering Chemistry Research 2023, 62 (43) , 17400-17407. https://doi.org/10.1021/acs.iecr.3c02684
Cecilia Bruni, Alessia Foglia, Anna Laura Eusebi, Nicola Frison, Çağrı Akyol, Francesco Fatone. Targeted Bio-Based Volatile Fatty Acid Production from Waste Streams through Anaerobic Fermentation: Link between Process Parameters and Operating Scale. ACS Sustainable Chemistry & Engineering 2021, 9 (30) , 9970-9987. https://doi.org/10.1021/acssuschemeng.1c02195
Mariana Matos, Rafaela A. P. Cruz, Pedro Cardoso, Fernando Silva, Elisabete B. Freitas, Gilda Carvalho, Maria A. M. Reis. Combined Strategies to Boost Polyhydroxyalkanoate Production from Fruit Waste in a Three-Stage Pilot Plant. ACS Sustainable Chemistry & Engineering 2021, 9 (24) , 8270-8279. https://doi.org/10.1021/acssuschemeng.1c02432
Chin-San Wu, Dung-Yi Wu, Shan-Shue Wang. Biodegradable Composite Nanofiber Containing Fish-Scale Extracts. ACS Applied Bio Materials 2021, 4 (1) , 462-469. https://doi.org/10.1021/acsabm.0c00955
Giulia Moretto, Laura Lorini, Paolo Pavan, Simona Crognale, Barbara Tonanzi, Simona Rossetti, Mauro Majone, Francesco Valentino. Biopolymers from Urban Organic Waste: Influence of the Solid Retention Time to Cycle Length Ratio in the Enrichment of a Mixed Microbial Culture (MMC). ACS Sustainable Chemistry & Engineering 2020, 8 (38) , 14531-14539. https://doi.org/10.1021/acssuschemeng.0c04980
Beatriz Melendez-Rodriguez, Sergio Torres-Giner, Laura Lorini, Francesco Valentino, Chris Sammon, Luis Cabedo, Jose Maria Lagaron. Valorization of Municipal Biowaste into Electrospun Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Biopapers for Food Packaging Applications. ACS Applied Bio Materials 2020, 3 (9) , 6110-6123. https://doi.org/10.1021/acsabm.0c00698
Fabiano Asunis, Paolo Dessì, Giorgia De Gioannis, Aldo Muntoni. VFA extraction through silicone membrane fosters PHA production from nutrient-rich biowaste. Bioresource Technology 2025, 426 , 132314. https://doi.org/10.1016/j.biortech.2025.132314
Jordana Georgin, Claudete Gindri Ramos, Jivago Schumacher de Oliveira, Younes Dehmani, Noureddine El Messaoudi, Lucas Meili, Dison S. P. Franco. A Critical Review of the Advances and Current Status of the Application of Adsorption in the Remediation of Micropollutants and Dyes Through the Use of Emerging Bio-Based Nanocomposites. Sustainability 2025, 17 (5) , 2012. https://doi.org/10.3390/su17052012
Irene Izarra, Irene Álvarez, F. Javier Pinar, Javier Mena. Urban Biorefinery Demonstration: Production of Polyhydroxyalkanoates from a Municipal Solid Waste. Applied Sciences 2025, 15 (6) , 3272. https://doi.org/10.3390/app15063272
Laura Pozo-Morales, Antonio Rosales Martínez, Enrique Baquerizo, Germán del Valle Agulla. Simulation Tool for the Techno-Economic Assessment of the Integrated Production of Polyhydroxyalkanoates as Value-Added Byproducts of a Wastewater Treatment Plant. Processes 2025, 13 (2) , 295. https://doi.org/10.3390/pr13020295
Cora M. Laumeyer, Julia Zimmer, Heidrun Steinmetz. From fruit juice wastewater to biopolymer – How the mixed microbial culture and PHA content develop over time. Chemical Engineering Journal 2025, 503 , 158314. https://doi.org/10.1016/j.cej.2024.158314
Antonio Mineo, Mark M.C. van Loosdrecht, Giorgio Mannina. From waste activated sludge to polyhydroxyalkanoate: Insights from a membrane-based enrichment process. Chemical Engineering Journal 2025, 506 , 160089. https://doi.org/10.1016/j.cej.2025.160089
Ghazal Srivastava, Kaoutar Aboudi, Vinay Kumar Tyagi, Absar Ahmad Kazmi. Role of intracellular storage polymers in simultaneous biological nutrient removal and resources recovery. Journal of Environmental Management 2025, 373 , 123720. https://doi.org/10.1016/j.jenvman.2024.123720
Vishal Ahuja, Pankaj Kumar Singh, Chandan Mahata, Jong-Min Jeon, Gopalakrishnan Kumar, Yung-Hun Yang, Shashi Kant Bhatia. A review on microbes mediated resource recovery and bioplastic (polyhydroxyalkanoates) production from wastewater. Microbial Cell Factories 2024, 23 (1) https://doi.org/10.1186/s12934-024-02430-0
Giovanna Pesante, Chiara Tesoriero, Emma Cadoria, Marco Andreolli, Silvia Lampis, Andrea Vettori, Nicola Frison. Valorisation of agricultural residues into Thauera sp. Sel9 microbial proteins for aquaculture. Environmental Technology & Innovation 2024, 36 , 103772. https://doi.org/10.1016/j.eti.2024.103772
Éamonn Walsh, Lekha Menon Margassery, Alejandro Rodriguez-Sanchez, David Wall, Paul Bolger, Marcel A.K. Jansen, Niall O'Leary. Integration of microbial bioreactors and Lemna minor cultivation for sustainable treatment of dairy processing wastewater. Journal of Water Process Engineering 2024, 67 , 106290. https://doi.org/10.1016/j.jwpe.2024.106290
Rui Guo, Xiaotong Cen, Bing-Jie Ni, Min Zheng. Bioplastic polyhydroxyalkanoate conversion in waste activated sludge. Journal of Environmental Management 2024, 370 , 122866. https://doi.org/10.1016/j.jenvman.2024.122866
Pema Lhamo, Biswanath Mahanty, Shishir Kumar Behera. Optimization of biomass and polyhydroxyalkanoate production by Cupriavidus necator using response surface methodology and genetic algorithm optimized artificial neural network. Biomass Conversion and Biorefinery 2024, 14 (17) , 20053-20068. https://doi.org/10.1007/s13399-023-04043-w
Shina Gautam, Alok Gautam, Juily Pawaday, Rekha Karshanbhai Kanzariya, Zhitong Yao. Current Status and Challenges in the Commercial Production of Polyhydroxyalkanoate-Based Bioplastic: A Review. Processes 2024, 12 (8) , 1720. https://doi.org/10.3390/pr12081720
Giorgio Mannina, Antonio Mineo. A comprehensive comparison between two strategies to produce polyhydroxyalkanoates from domestic sewage sludge. Journal of Cleaner Production 2024, 468 , 143052. https://doi.org/10.1016/j.jclepro.2024.143052
Emmanuel da Silva Côgo Miguel, Beatriz Santos Machado, Ana Paula Silva Teles, Thalita Ferreira da Silva, Fernando Jorge Corrêa Magalhães Filho, Priscila Sabioni Cavalheri. Optimizing sewage treatment by UV/H2O2 process and vertical flow constructed wetland integration. Journal of Water Process Engineering 2024, 64 , 105580. https://doi.org/10.1016/j.jwpe.2024.105580
Zixin Zhang, Yufen Wang, Xiaomin Wang, Yaobin Zhang, Tingting Zhu, Lai Peng, Yifeng Xu, Xueming Chen, Dongbo Wang, Bing-Jie Ni, Yiwen Liu. Towards scaling-up implementation of polyhydroxyalkanoate (PHA) production from activated sludge: Progress and challenges. Journal of Cleaner Production 2024, 447 , 141542. https://doi.org/10.1016/j.jclepro.2024.141542
Zain Ali, Muhammad Abdullah, Muhammad Talha Yasin, Kinza Amanat, Khurshid Ahmad, Ishfaq Ahmed, Muther Mansoor Qaisrani, Jallat Khan. Organic waste-to-bioplastics: Conversion with eco-friendly technologies and approaches for sustainable environment. Environmental Research 2024, 244 , 117949. https://doi.org/10.1016/j.envres.2023.117949
Sundramurthy Venkatesa Prabhu, Abas Siraj Hamda, Mani Jayakumar, Selvakumar Periyasamy, Subramanian Manivannan, Workisa Bacha. Production strategies and potential repercussion of sewage sludge biochar as a futuristic paradigm toward environmental beneficiation: A comprehensive review. Environmental Quality Management 2024, 33 (3) , 1-19. https://doi.org/10.1002/tqem.22007
Jeniffer Gracia, Armando Espinosa, Nubia Moreno, Iván Cabeza. Evaluation of the production and extraction of polyhydroxybutyrate from volatile fatty acids and using mixed cultures of PTAR and B. cepacia. Environmental Research 2024, 96 , 118448. https://doi.org/10.1016/j.envres.2024.118448
J.R. Almeida, E. Serrano León, F. Rogalla, J.C. Fradinho, A. Oehmen, M.A.M. Reis. Polyhydroxyalkanoates production in purple phototrophic bacteria ponds: A breakthrough in outdoor pilot-scale operation. Science of The Total Environment 2024, 912 , 168899. https://doi.org/10.1016/j.scitotenv.2023.168899
Guangbao Zhang, Weishuang Zheng, Xinyi Bai, Libo Xu, Kang Li, Mengjun Zhang, Yi Huang. Polyhydroxyalkanoates (PHAs) biological recovery approaches and protein-mediated secretion model hypothesis. Journal of Cleaner Production 2024, 440 , 140851. https://doi.org/10.1016/j.jclepro.2024.140851
Francesco Traina, Santo Fabio Corsino, Marco Capodici, Enrico Licitra, Gaetano Di Bella, Michele Torregrossa, Gaspare Viviani. Combined recovery of polyhydroxyalkanoates and reclaimed water in the mainstream of a WWTP for agro-food industrial wastewater valorisation by membrane bioreactor technology. Journal of Environmental Management 2024, 351 , 119836. https://doi.org/10.1016/j.jenvman.2023.119836
Wafa Al-Gethami, Muhammad Azam Qamar, Mohammad Shariq, Abdel-Nasser M. A. Alaghaz, Ahmad Farhan, Ashwaq A. Areshi, M. Hisham Alnasir. Emerging environmentally friendly bio-based nanocomposites for the efficient removal of dyes and micropollutants from wastewater by adsorption: a comprehensive review. RSC Advances 2024, 14 (4) , 2804-2834. https://doi.org/10.1039/D3RA06501D
Constantinos Noutsopoulos, Victoria Gkoutzioupa, Evina Katsou, Nicola Frison, Francesco Fatone, Simos Malamis. Integrated selection of PHA-storing biomass and nitrogen removal via nitrite from sludge reject water: a mathematical model. Environmental Technology 2024, 45 (1) , 73-86. https://doi.org/10.1080/09593330.2022.2099311
S. Mann, J. G. Sharma, R. Kataria. Microbial accumulation of bioplastics from waste stream: recent advancements and applications. International Journal of Environmental Science and Technology 2024, 21 (2) , 2279-2306. https://doi.org/10.1007/s13762-023-05126-x
Paolo Costa, Marina Basaglia, Sergio Casella, Christian Kennes, Lorenzo Favaro, María C. Veiga. Autotrophic production of polyhydroxyalkanoates using acidogenic-derived H2 and CO2 from fruit waste. Bioresource Technology 2023, 390 , 129880. https://doi.org/10.1016/j.biortech.2023.129880
Saima Jan, Awdhesh Kumar Mishra, Mujtaba Aamir Bhat, Mudasir Ahmad Bhat, Arif Tasleem Jan. Pollutants in aquatic system: a frontier perspective of emerging threat and strategies to solve the crisis for safe drinking water. Environmental Science and Pollution Research 2023, 30 (53) , 113242-113279. https://doi.org/10.1007/s11356-023-30302-4
Tanlong Zhou, Shunli Wang, Wanqin Zhang, Fubin Yin, Qitao Cao, Tianjing Lian, Hongmin Dong. Polyhydroxyalkanoates production from lactic acid fermentation broth of agricultural waste without extra purification: The effect of concentrations. Environmental Technology & Innovation 2023, 32 , 103311. https://doi.org/10.1016/j.eti.2023.103311
Laura Isern-Cazorla, Antonio Mineo, María Eugenia Suárez-Ojeda, Giorgio Mannina. Effect of organic loading rate on the production of Polyhydroxyalkanoates from sewage sludge. Journal of Environmental Management 2023, 343 , 118272. https://doi.org/10.1016/j.jenvman.2023.118272
Lalit Goswami, Anamika Kushwaha, Suchada Chanprateep Napathorn, Beom Soo Kim. Valorization of organic wastes using bioreactors for polyhydroxyalkanoate production: Recent advancement, sustainable approaches, challenges, and future perspectives. International Journal of Biological Macromolecules 2023, 247 , 125743. https://doi.org/10.1016/j.ijbiomac.2023.125743
Chiara Bastianelli, Giovanna Pesante, Stefano Ambrosini, Anita Zamboni, Nicola Frison. Upcycling of PHA-producing bacteria for biostimulants production and polyhydroxyalkanoates recovery. Science of The Total Environment 2023, 888 , 164238. https://doi.org/10.1016/j.scitotenv.2023.164238
Bruno C. Marreiros, Mónica Carvalheira, Cláudia Henriques, Daniela Pequito, Yen Nguyen, Runar G. Solstad, J. Johannes Eksteen, Maria A.M. Reis. Pilot-scale valorisation of salmon peptone into polyhydroxyalkanoates by mixed microbial cultures under conditions of high ammonia concentration. Journal of Environmental Chemical Engineering 2023, 11 (3) , 110100. https://doi.org/10.1016/j.jece.2023.110100
Richa Prasad Mahato, Saurabh Kumar, Padma Singh. Production of polyhydroxyalkanoates from renewable resources: a review on prospects, challenges and applications. Archives of Microbiology 2023, 205 (5) https://doi.org/10.1007/s00203-023-03499-8
Truus de Vrije, Ricardo M. Nagtegaal, Ruud M. Veloo, Frans H.J. Kappen, Frits A. de Wolf. Medium chain length polyhydroxyalkanoate produced from ethanol by Pseudomonas putida grown in liquid obtained from acidogenic digestion of organic municipal solid waste. Bioresource Technology 2023, 375 , 128825. https://doi.org/10.1016/j.biortech.2023.128825
Tülin Yılmaz Nayır, Selver Konuk, Serdar Kara. Extraction of polyhydroxyalkanoate from activated sludge using supercritical carbon dioxide process and biopolymer characterization. Journal of Biotechnology 2023, 364 , 50-57. https://doi.org/10.1016/j.jbiotec.2023.01.011
Roberto Lauri, Emma Incocciati, Biancamaria Pietrangeli, Lionel Nguemna Tayou, Francesco Valentino, Marco Gottardo, Mauro Majone. Hazop Analysis of a Bioprocess for Polyhydroxyalkanoate (PHA) Production from Organic Waste: Part A. Fermentation 2023, 9 (2) , 99. https://doi.org/10.3390/fermentation9020099
Roberto Lauri, Emma Incocciati, Biancamaria Pietrangeli, Lionel Nguemna Tayou, Francesco Valentino, Marco Gottardo, Mauro Majone. Hazop Analysis of a Bioprocess for Polyhydroxyalkanoate (PHA) Production from Organic Waste: Part B. Fermentation 2023, 9 (2) , 154. https://doi.org/10.3390/fermentation9020154
Giovanna Pesante, Nicola Frison. Recovery of bio-based products from PHA-rich biomass obtained from biowaste: A review. Bioresource Technology Reports 2023, 21 , 101345. https://doi.org/10.1016/j.biteb.2023.101345
Dario Presti, María Eugenia Suárez-Ojeda, Giorgio Mannina. Integration of polyhydroxyalkanoates (PHAs) production into urban wastewater treatment plants. 2023, 31-60. https://doi.org/10.1016/B978-0-323-99920-5.00001-9
Giuseppe Gallo, Walter Arancio, Emilia Palazzotto, Fanny Claire Capri, Rosa Alduina. Microbial biotechnology for wastewater treatment into circular economy. 2023, 333-354. https://doi.org/10.1016/B978-0-323-99920-5.00003-2
Mateo Saavedra del Oso, Miguel Mauricio-Iglesias, Almudena Hospido, Bernhard Steubing. Prospective LCA to provide environmental guidance for developing waste-to-PHA biorefineries. Journal of Cleaner Production 2023, 383 , 135331. https://doi.org/10.1016/j.jclepro.2022.135331
Anamika Kushwaha, Nidhi Hans, Ishrat Jahan Badruddin, Won-Gyun Oh, Rishabh Shukla, Lalit Goswami, Beom Soo Kim. Polyhydroxyalkanoates production from biowastes: A route towards environmental sustainability. 2023, 143-182. https://doi.org/10.1016/B978-0-323-91149-8.00013-2
Elena Rossi, Isabella Pecorini, Antonio Panico, Renato Iannelli. Impact of reactor configuration and relative operating conditions on volatile fatty acids production from organic waste. Environmental Technology Reviews 2022, 11 (1) , 156-186. https://doi.org/10.1080/21622515.2022.2139641
Chris M. Vermeer, Maaike Nielsen, Vincent Eckhardt, Matthijs Hortensius, Jelmer Tamis, Stephen J. Picken, Gabrie M.H. Meesters, Robbert Kleerebezem. Systematic solvent screening and selection for polyhydroxyalkanoates (PHBV) recovery from biomass. Journal of Environmental Chemical Engineering 2022, 10 (6) , 108573. https://doi.org/10.1016/j.jece.2022.108573
Shuping Wu, Weijian Shi, Kanghui Li, Jiawei Cai, Lingyun Chen. Recent advances on sustainable bio-based materials for water treatment: Fabrication, modification and application. Journal of Environmental Chemical Engineering 2022, 10 (6) , 108921. https://doi.org/10.1016/j.jece.2022.108921
Paola Critelli, Giovanna Pesante, Stefania Lupinelli, Michele Modesti, Silvia Zanatta, Federico Battista, David Bolzonella, Nicola Frison. Production and characterisation of PHAs by pure culture using protein hydrolysates as sole carbon source. Environmental Technology & Innovation 2022, 28 , 102919. https://doi.org/10.1016/j.eti.2022.102919
Fabiano Asunis, Alessandra Carucci, Giorgia De Gioannis, Gianluigi Farru, Aldo Muntoni, Alessandra Polettini, Raffaella Pomi, Andreina Rossi, Daniela Spiga. Combined biohydrogen and polyhydroxyalkanoates production from sheep cheese whey by a mixed microbial culture. Journal of Environmental Management 2022, 322 , 116149. https://doi.org/10.1016/j.jenvman.2022.116149
Naima Khan, Iftikhar Ali, Sumaira Mazhar, Sajida Munir, Rida Batool, Nazia Jamil. Co-Culture of Halotolerant Bacteria to Produce Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Using Sewage Wastewater Substrate. Polymers 2022, 14 (22) , 4963. https://doi.org/10.3390/polym14224963
Fabiano Asunis, Giovanna Cappai, Alessandra Carucci, Giorgia De Gioannis, Paolo Dessì, Aldo Muntoni, Alessandra Polettini, Raffaella Pomi, Andreina Rossi, Daniela Spiga, Cristina Trois. Dark fermentative volatile fatty acids production from food waste: A review of the potential central role in waste biorefineries. Waste Management & Research: The Journal for a Sustainable Circular Economy 2022, 40 (11) , 1571-1593. https://doi.org/10.1177/0734242X221103940
Federico Battista, Giuseppe Strazzera, Francesco Valentino, Marco Gottardo, Marianna Villano, Mariana Matos, Fernando Silva, Maria.A. M. Reis, Joan Mata-Alvarez, Sergi Astals, Joan Dosta, Rhys Jon Jones, Jaime Massanet-Nicolau, Alan Guwy, Paolo Pavan, David Bolzonella, Mauro Majone. New insights in food waste, sewage sludge and green waste anaerobic fermentation for short-chain volatile fatty acids production: A review. Journal of Environmental Chemical Engineering 2022, 10 (5) , 108319. https://doi.org/10.1016/j.jece.2022.108319
Federico Verdini, Silvia Tabasso, Francesco Mariatti, Francesca Bosco, Chiara Mollea, Emanuela Calcio Gaudino, Alessio Cirio, Giancarlo Cravotto. From Agri-Food Wastes to Polyhydroxyalkanoates through a Sustainable Process. Fermentation 2022, 8 (10) , 556. https://doi.org/10.3390/fermentation8100556
Marco Gottardo, David Bolzonella, Giulia Adele Tuci, Francesco Valentino, Mauro Majone, Paolo Pavan, Federico Battista. Producing volatile fatty acids and polyhydroxyalkanoates from foods by-products and waste: A review. Bioresource Technology 2022, 361 , 127716. https://doi.org/10.1016/j.biortech.2022.127716
Niravkumar Mahendrasinh Kosamia, Mahdieh Samavi, Kachuol Piok, Sudip Kumar Rakshit. Perspectives for scale up of biorefineries using biochemical conversion pathways: Technology status, techno-economic, and sustainable approaches. Fuel 2022, 324 , 124532. https://doi.org/10.1016/j.fuel.2022.124532
Mridul Umesh, Sabarathinam Shanmugam, Timo Kikas, Nguyen Thuy Lan Chi, Arivalagan Pugazhendhi. Progress in bio-based biodegradable polymer as the effective replacement for the engineering applicators. Journal of Cleaner Production 2022, 362 , 132267. https://doi.org/10.1016/j.jclepro.2022.132267
Paloma Cabecas Segura, Quentin De Meur, Abbas Alloul, Audrey Tanghe, Rob Onderwater, Siegfried E. Vlaeminck, Alain Vande Wouwer, Ruddy Wattiez, Laurent Dewasme, Baptiste Leroy. Preferential photoassimilation of volatile fatty acids by purple non-sulfur bacteria: Experimental kinetics and dynamic modelling. Biochemical Engineering Journal 2022, 186 , 108547. https://doi.org/10.1016/j.bej.2022.108547
A. Lanfranchi, G. Tassinato, F. Valentino, G.A. Martinez, E. Jones, C. Gioia, L. Bertin, C. Cavinato. Hydrodynamic cavitation pre-treatment of urban waste: Integration with acidogenic fermentation, PHAs synthesis and anaerobic digestion processes. Chemosphere 2022, 301 , 134624. https://doi.org/10.1016/j.chemosphere.2022.134624
Francesca Crisafi, Francesco Valentino, Federico Micolucci, Renata Denaro. From Organic Wastes and Hydrocarbons Pollutants to Polyhydroxyalkanoates: Bioconversion by Terrestrial and Marine Bacteria. Sustainability 2022, 14 (14) , 8241. https://doi.org/10.3390/su14148241
Patrick Sekoai, Obinna Ezeokoli, Kelvin Yoro, Orevaoghene Eterigho-Ikelegbe, Olivier Habimana, Samuel Iwarere, Michael Daramola, Tunde Ojumu. The production of polyhydroxyalkanoates using volatile fatty acids derived from the acidogenic biohydrogen effluents: An overview. Bioresource Technology Reports 2022, 18 , 101111. https://doi.org/10.1016/j.biteb.2022.101111
Laura Lorini, Gianluca Munarin, Gaia Salvatori, Sara Alfano, Paolo Pavan, Mauro Majone, Francesco Valentino. Sewage sludge as carbon source for polyhydroxyalkanoates: a holistic approach at pilot scale level. Journal of Cleaner Production 2022, 354 , 131728. https://doi.org/10.1016/j.jclepro.2022.131728
Santo Fabio Corsino, Daniele Di Trapani, Francesco Traina, Ilenia Cruciata, Laura Scirè Calabrisotto, Francesco Lopresti, Vincenzo La Carrubba, Paola Quatrini, Michele Torregrossa, Gaspare Viviani. Integrated production of biopolymers with industrial wastewater treatment: Effects of OLR on process yields, biopolymers characteristics and mixed microbial community enrichment. Journal of Water Process Engineering 2022, 47 , 102772. https://doi.org/10.1016/j.jwpe.2022.102772
Crognale Simona, Lorini Laura, Valentino Francesco, Villano Marianna, Marzo Gago Cristina, Tonanzi Barbara, Majone Mauro, Rossetti Simona. Effect of the organic loading rate on the PHA-storing microbiome in sequencing batch reactors operated with uncoupled carbon and nitrogen feeding. Science of The Total Environment 2022, 825 , 153995. https://doi.org/10.1016/j.scitotenv.2022.153995
Neda Amanat, Bruna Matturro, Marianna Villano, Laura Lorini, Marta Maria Rossi, Marco Zeppilli, Simona Rossetti, Marco Petrangeli Papini. Enhancing the biological reductive dechlorination of trichloroethylene with PHA from mixed microbial cultures (MMC). Journal of Environmental Chemical Engineering 2022, 10 (2) , 107047. https://doi.org/10.1016/j.jece.2021.107047
Shikha Guleria, Harpreet Singh, Vamika Sharma, Neha Bhardwaj, Shailendra Kumar Arya, Sanjeev Puri, Madhu Khatri. Polyhydroxyalkanoates production from domestic waste feedstock: A sustainable approach towards bio-economy. Journal of Cleaner Production 2022, 340 , 130661. https://doi.org/10.1016/j.jclepro.2022.130661
Simone Bagatella, Riccardo Ciapponi, Elena Ficara, Nicola Frison, Stefano Turri. Production and Characterization of Polyhydroxyalkanoates from Wastewater via Mixed Microbial Cultures and Microalgae. Sustainability 2022, 14 (6) , 3704. https://doi.org/10.3390/su14063704
Alan Werker, Laura Lorini, Marianna Villano, Francesco Valentino, Mauro Majone. Modelling Mixed Microbial Culture Polyhydroxyalkanoate Accumulation Bioprocess towards Novel Methods for Polymer Production Using Dilute Volatile Fatty Acid Rich Feedstocks. Bioengineering 2022, 9 (3) , 125. https://doi.org/10.3390/bioengineering9030125
Elena Rossi, Isabella Pecorini, Paola Paoli, Renato Iannelli. Plug-flow reactor for volatile fatty acid production from the organic fraction of municipal solid waste: Influence of organic loading rate. Journal of Environmental Chemical Engineering 2022, 10 (1) , 106963. https://doi.org/10.1016/j.jece.2021.106963
Maximilian T. Schmid, Eva Sykacek, Kevin O'Connor, Markus Omann, Norbert Mundigler, Markus Neureiter. Pilot scale production and evaluation of mechanical and thermal properties of P( 3HB ) from Bacillus megaterium cultivated on desugarized sugar beet molasses. Journal of Applied Polymer Science 2022, 139 (3) https://doi.org/10.1002/app.51503
Ilke Pala-Ozkok, Gülsüm Emel Zengin, Didem Okutman Taş, Nevin Yağcı, Didem Güven, H. Güçlü Insel, Emine Çokgör. Polyhydroxyalkanoate production from food industry residual streams using mixed microbial cultures. 2022, 265-284. https://doi.org/10.1016/B978-0-323-90178-9.00010-X
Mónica Carvalheira, Bruno C. Marreiros, M.A.M Reis. Acids (VFAs) and bioplastic (PHA) recovery. 2022, 245-254. https://doi.org/10.1016/B978-0-323-90178-9.00016-0
Mukesh Kumar, Inderpal Devgon, Ritu Bala, Abhishek Rana, Manpreet Kaur Somal, Rohan Samir Kumar Sachan, Arun Karnwal. Integrated production of polyhydroxyalkonate (bioplastic) with municipal wastewater and sludge treatment for sustainable development. 2022, 283-303. https://doi.org/10.1016/B978-0-323-91180-1.00011-9
Gabriella Papa, Tommy Pepe Sciarria, Barbara Scaglia, Fabrizio Adani. Diversifying the products from the organic fraction of municipal solid waste (OFMSW) by producing polyhydroxyalkanoates from the liquid fraction and biomethane from the residual solid fraction. Bioresource Technology 2022, 344 , 126180. https://doi.org/10.1016/j.biortech.2021.126180
Qi Hao Goh, Amr A. Farouk, IreneMei Leng Chew. Optimizing the bioplastic chemical building block with wastewater sludge as the feedstock using carbon-hydrogen-oxygen framework. Resources, Conservation and Recycling 2022, 176 , 105920. https://doi.org/10.1016/j.resconrec.2021.105920
Chris M. Vermeer, Maaike Nielsen, Vincent Eckhardt, Matthijs Hortensius, Jelmer Tamis, Stephen J. Picken, Gabrie M. H. Meesters, Robbert Kleerebezem. Systematic Solvent Screening and Selection for Polyhydroxyalkanoates (Phbv) Recovery from Biomass. SSRN Electronic Journal 2022, 13 https://doi.org/10.2139/ssrn.4122159
Fabiano Asunis, Alessandra Carucci, Giorgia De Gioannis, Gianluigi Farru, Aldo Muntoni, Alessandra Polettini, Raffaella Pomi, Andreina Rossi, Daniela Spiga. Combined Biohydrogen and Polyhydroxyalkanoates Production from Sheep Cheese Whey by a Mixed Microbial Culture. SSRN Electronic Journal 2022, 244 https://doi.org/10.2139/ssrn.4170586
Sonam Tripathi, Diane Purchase, Sarah Al-Rashed, Ram Chandra. Microbial community dynamics and their relationships with organic and metal pollutants of sugarcane molasses-based distillery wastewater sludge. Environmental Pollution 2022, 292 , 118267. https://doi.org/10.1016/j.envpol.2021.118267
Mónica Carvalheira, Loic Hilliou, Catarina S.S. Oliveira, Eliana C. Guarda, Maria A.M. Reis. Polyhydroxyalkanoates from industrial cheese whey: Production and characterization of polymers with differing hydroxyvalerate content. Current Research in Biotechnology 2022, 4 , 211-220. https://doi.org/10.1016/j.crbiot.2022.03.004
Nausheen Jaffur, Pratima Jeetah, Gopalakrishnan Kumar. A review on enzymes and pathways for manufacturing polyhydroxybutyrate from lignocellulosic materials. 3 Biotech 2021, 11 (11) https://doi.org/10.1007/s13205-021-03009-x
Jesús E. Rodríguez G., Silvia Brojanigo, Marina Basaglia, Lorenzo Favaro, Sergio Casella. Efficient production of polyhydroxybutyrate from slaughterhouse waste using a recombinant strain of Cupriavidus necator DSM 545. Science of The Total Environment 2021, 794 , 148754. https://doi.org/10.1016/j.scitotenv.2021.148754
Vasanth Kumar Vaithyanathan, Hubert Cabana. Integrated Biotechnology Management of Biosolids: Sustainable Ways to Produce Value—Added Products. Frontiers in Water 2021, 3 https://doi.org/10.3389/frwa.2021.729679
Vineet Kumar, Shaili Srivastava, Indu Shekhar Thakur. Enhanced recovery of polyhydroxyalkanoates from secondary wastewater sludge of sewage treatment plant: Analysis and process parameters optimization. Bioresource Technology Reports 2021, 15 , 100783. https://doi.org/10.1016/j.biteb.2021.100783
Anouk F. Duque, Riccardo Campo, Angeles Val del Rio, Catarina L. Amorim. Wastewater Valorization: Practice around the World at Pilot- and Full-Scale. International Journal of Environmental Research and Public Health 2021, 18 (18) , 9466. https://doi.org/10.3390/ijerph18189466
Marta M. Rossi, Edoardo Dell’Armi, Laura Lorini, Neda Amanat, Marco Zeppilli, Marianna Villano, Marco Petrangeli Papini. Combined Strategies to Prompt the Biological Reduction of Chlorinated Aliphatic Hydrocarbons: New Sustainable Options for Bioremediation Application. Bioengineering 2021, 8 (8) , 109. https://doi.org/10.3390/bioengineering8080109
Sara Alfano, Laura Lorini, Mauro Majone, Fabio Sciubba, Francesco Valentino, Andrea Martinelli. Ethylic Esters as Green Solvents for the Extraction of Intracellular Polyhydroxyalkanoates Produced by Mixed Microbial Culture. Polymers 2021, 13 (16) , 2789. https://doi.org/10.3390/polym13162789
Erica Pascale, Elena Franchitti, Chiara Caredda, Stefania Fornasero, Giulia Carletto, Biancamaria Pietrangeli, Francesco Valentino, Paolo Pavan, Giorgio Gilli, Elisa Anedda, Deborah Traversi. Bioaerosol Emissions during Organic Waste Treatment for Biopolymer Production: A Case Study. Atmosphere 2021, 12 (8) , 1069. https://doi.org/10.3390/atmos12081069
Francisco G. Blanco, Natalia Hernández, Virginia Rivero-Buceta, Beatriz Maestro, Jesús M. Sanz, Aránzazu Mato, Ana M. Hernández-Arriaga, M. Auxiliadora Prieto. From Residues to Added-Value Bacterial Biopolymers as Nanomaterials for Biomedical Applications. Nanomaterials 2021, 11 (6) , 1492. https://doi.org/10.3390/nano11061492
Ángel Estévez-Alonso, Ruizhe Pei, Mark C.M. van Loosdrecht, Robbert Kleerebezem, Alan Werker. Scaling-up microbial community-based polyhydroxyalkanoate production: status and challenges. Bioresource Technology 2021, 327 , 124790. https://doi.org/10.1016/j.biortech.2021.124790
Laura Lorini, Andrea Martinelli, Paolo Pavan, Mauro Majone, Francesco Valentino. Downstream processing and characterization of polyhydroxyalkanoates (PHAs) produced by mixed microbial culture (MMC) and organic urban waste as substrate. Biomass Conversion and Biorefinery 2021, 11 (2) , 693-703. https://doi.org/10.1007/s13399-020-00788-w
Shashi Kant Bhatia, Sachin V. Otari, Jong-Min Jeon, Ranjit Gurav, Yong-Keun Choi, Ravi Kant Bhatia, Arivalagan Pugazhendhi, Vinod Kumar, J. Rajesh Banu, Jeong-Jun Yoon, Kwon-Young Choi, Yung-Hun Yang. Biowaste-to-bioplastic (polyhydroxyalkanoates): Conversion technologies, strategies, challenges, and perspective. Bioresource Technology 2021, 326 , 124733. https://doi.org/10.1016/j.biortech.2021.124733
Neda Amanat, Bruna Matturro, Marta Rossi, Francesco Valentino, Marianna Villano, Marco Petrangeli Papini. Assessment of Long-Term Fermentability of PHA-Based Materials from Pure and Mixed Microbial Cultures for Potential Environmental Applications. Water 2021, 13 (7) , 897. https://doi.org/10.3390/w13070897
Laura Lorini, Andrea Martinelli, Giorgio Capuani, Nicola Frison, Maria Reis, Bruno Sommer Ferreira, Marianna Villano, Mauro Majone, Francesco Valentino. Characterization of Polyhydroxyalkanoates Produced at Pilot Scale From Different Organic Wastes. Frontiers in Bioengineering and Biotechnology 2021, 9 https://doi.org/10.3389/fbioe.2021.628719
Chiara Cavaliere, Anna Laura Capriotti, Andrea Cerrato, Laura Lorini, Carmela Maria Montone, Francesco Valentino, Aldo Laganà, Mauro Majone. Identification and Quantification of Polycyclic Aromatic Hydrocarbons in Polyhydroxyalkanoates Produced from Mixed Microbial Cultures and Municipal Organic Wastes at Pilot Scale. Molecules 2021, 26 (3) , 539. https://doi.org/10.3390/molecules26030539
Asmita Gupta, Madan Kumar, Shaili Srivastava. Recent Advances in Wastewater Sludge Valorization. 2021, 225-247. https://doi.org/10.1007/978-981-15-9696-4_10

Load all citations

Download PDF

Get e-Alerts

Industrial & Engineering Chemistry Research

Cite this: Ind. Eng. Chem. Res. 2019, 58, 27, 12149–12158

Click to copy citationCitation copied!

https://doi.org/10.1021/acs.iecr.9b01831

Published June 10, 2019

Request reuse permissions

Article Views

Altmetric

Citations

115

Learn about these metrics

Article Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.

Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.

The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated.

Abstract
High Resolution Image
Download MS PowerPoint Slide
Figure 1
Figure 1. Process scheme developed at pilot scale for OFMSW and SS valorization toward PHA production.
High Resolution Image
Download MS PowerPoint Slide
Figure 2
Figure 2. VFA, COD_SOL, and pH evolution in the fermented feedstock (A); VFA distribution under the three different conditions tested (B).
High Resolution Image
Download MS PowerPoint Slide
Figure 3
Figure 3. Main parameters monitored in SBR: VFA, COD_SOL, PHA, ammonium, and phosphate in a typical SBR FL-III cycle (A). Feast phase/cycle length ratio (B), maximum and minimum PHA concentration (C), and storage rate and yield (D) in the three different SBR runs.
High Resolution Image
Download MS PowerPoint Slide
Figure 4
Figure 4. Fed-batch accumulations conducted with biomass enriched in SBR FL-III run: synthetic acetate (A) and ffFL-III (B) as feeding solutions.
High Resolution Image
Download MS PowerPoint Slide
Figure 5
Figure 5. Mass flow diagram of PHA production from OFMSW-SS mixture.
High Resolution Image
Download MS PowerPoint Slide
References
This article references 36 other publications.
1. 1
  Morgan-Sagastume, F. Characterisation of open, mixed microbial cultures for polyhydroxyalkanoate (PHA) production. Rev. Environ. Sci. Bio/Technol. 2016, 15, 593– 625, DOI: 10.1007/s11157-016-9411-0
  1
  Characterisation of open, mixed microbial cultures for polyhydroxyalkanoate (PHA) production
  Morgan-Sagastume, Fernando
  Reviews in Environmental Science and Bio/Technology (2016), 15 (4), 593-625CODEN: RESBC6; ISSN:1569-1705. (Springer)
  A review. The microbial community structure and population dynamics in both the biomass enrichment and the PHA accumulation process have not been equally analyzed. PHA-storing bacteria have been identified predominantly within the classes of Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria. Mol. techniques and microscopy have been preferentially used to characterize microbial diversity, abundance and activity in PHA-storing MMC. Fluorescence in situ hybridization remains relevant for the spatial identification and quantification of PHA-storing bacteria, and in tandem with Nile blue A staining helps identify actively PHA-storing bacteria. 16S rRNA-based fingerprinting is useful for describing dynamics in microbial community structure rather than diversity, and new generation sequencing provides a high-throughput characterization of microbial diversity, dynamics and relative abundance. The dominant bacteria and their dynamics in bioreactors enriching for MMC with PHA-storage capacity and actively accumulating PHA are further covered with respect to the operating conditions used to select microbial communities for the PHA-storage phenotype. The specification of the PHA-storage phenotype and metabolic activity in identified bacteria remains a challenge in the study of PHA-storing MMC.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhslygtbvI&md5=d372b09d707cfe56c6bc8d365be8fbd7
2. 2
  Kourmentza, C.; Plácido, J.; Venetsaneas, N.; Burniol-Figols, A.; Varrone, C.; Gavala, H. N.; Reis, M. A. M. Recent advances and challenges towards sustainable polyhydroxyalkanoate (PHA) production. Bioengineering 2017, 4, 55, DOI: 10.3390/bioengineering4020055
  There is no corresponding record for this reference.
3. 3
  Rodriguez-Perez, S.; Serrano, A.; Pantión, A. A.; Alonso-Farinas, B. Challenges of scaling-up PHA production from waste streams. A review. J. Environ. Manage. 2018, 205, 215– 230, DOI: 10.1016/j.jenvman.2017.09.083
  3
  Challenges of scaling-up PHA production from waste streams. A review
  Rodriguez-Perez, Santiago; Serrano, Antonio; Pantion, Alba A.; Alonso-Farinas, Bernabe
  Journal of Environmental Management (2018), 205 (), 215-230CODEN: JEVMAW; ISSN:0301-4797. (Elsevier Ltd.)
  The search for new materials that replace fossil fuel-based plastics has been focused on biopolymers with similar physicochem. properties to fossil fuel-based plastics, such as Polyhydroxyalkanoates (PHA). The present paper reviews the challenges of scaling-up PHA prodn. from waste streams during the period from 2014 to 2016, focusing on the feasibility of the alternatives and the most promising alternatives to its scaling-up. The reviewed research studies mainly focus on reducing costs or obtaining more valuable polymers. In the future, the integration of PHA prodn. into processes such as wastewater treatment plants, hydrogen prodn. or biodiesel factories could enhance its implementation at industrial scale.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhs1akur7K&md5=0d7e6f6829ab0015407b8ad570fe7db4
4. 4
  Valentino, F.; Morgan-Sagastume, F.; Campanari, S.; Villano, M.; Werker, A.; Majone, M. Carbon recovery from wastewater through bioconversion into biodegradable polymers. New Biotechnol. 2017, 37, 9– 23, DOI: 10.1016/j.nbt.2016.05.007
  4
  Carbon recovery from wastewater through bioconversion into biodegradable polymers
  Valentino, Francesco; Morgan-Sagastume, Fernando; Campanari, Sabrina; Villano, Marianna; Werker, Alan; Majone, Mauro
  New Biotechnology (2017), 37 (Part_A), 9-23CODEN: NBEIBR; ISSN:1871-6784. (Elsevier B.V.)
  Polyhydroxyalkanoates (PHA) are biodegradable polyesters that can be produced in bioprocesses from renewable resources in contrast to fossil-based bio-recalcitrant polymers. Research efforts have been directed towards establishing tech. feasibility in the use of mixed microbial cultures (MMC) for PHA prodn. using residuals as feedstock, mainly consisting of industrial process effluent waters and wastewaters. In this context, PHA prodn. can be integrated with waste and wastewater biol. treatment, with concurrent benefits of resource recovery and sludge minimization. Over the past 15 years, much of the research on MMC PHA prodn. has been performed at lab. scale in three process elements as follows: (1) acidogenic fermn. to obtain a volatile fatty acid (VFA)-rich stream, (2) a dedicated biomass prodn. yielding MMCs enriched with PHA-storing potential, and (3) a PHA accumulation step where (1) and (2) outputs are combined in a final biopolymer prodn. bioprocess. This paper reviews the recent developments on MMC PHA prodn. from synthetic and real wastewaters. The goals of the crit. review are: a) to highlight the progress of the three-steps in MMC PHA prodn., and as well to recommend room for improvements, and b) to explore the ideas and developments of integration of PHA prodn. within existing infrastructure of municipal and industrial wastewaters treatment. There has been much tech. advancement of ideas and results in the MMC PHA rich biomass prodn. However, clear demonstration of prodn. and recovery of the polymers within a context of product quality over an extended period of time, within an up-scalable com. viable context of regional material supply, and with well-defined quality demands for specific intent of material use, is a hill that still needs to be climbed in order to truly spur on innovations for this field of research and development.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhtVGit77O&md5=f2914ad754e3112c414c543569a0e864
5. 5
  Gholami, A.; Mohkam, M.; Rasoul-Amini, S.; Ghasemi, Y. Industrial production of polyhydroxyalkanoates by bacteria: opportunities and challenges. Minerva Biotechnol. 2016, 28, 59– 74
  There is no corresponding record for this reference.
6. 6
  Morgan-Sagastume, F.; Hjort, M.; Cirne, D.; Gérardin, F.; Lacroix, S.; Gaval, G.; Karabegovic, L.; Alexandersson, T.; Johansson, P.; Karlsson, A.; Bengtsson, S.; Arcos-Hernández, M.; Magnusson, P.; Werker, A. Integrated production of polyhydroxyalkanoates (PHAs) with municipal wastewater and sludge treatment at pilot scale. Bioresour. Technol. 2015, 181, 78– 89, DOI: 10.1016/j.biortech.2015.01.046
  6
  Integrated production of polyhydroxyalkanoates (PHAs) with municipal wastewater and sludge treatment at pilot scale
  Morgan-Sagastume, F.; Hjort, M.; Cirne, D.; Gerardin, F.; Lacroix, S.; Gaval, G.; Karabegovic, L.; Alexandersson, T.; Johansson, P.; Karlsson, A.; Bengtsson, S.; Arcos-Hernandez, M. V.; Magnusson, P.; Werker, A.
  Bioresource Technology (2015), 181 (), 78-89CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
  A pilot-scale process was operated over 22 mo at the Brussels North Wastewater Treatment Plant (WWTP) in order to evaluate polyhydroxyalkanoate (PHA) prodn. integration with services of municipal wastewater and sludge management. Activated sludge was produced with PHA accumulation potential (PAP) by applying feast-famine selection while treating the readily biodegradable COD from influent wastewater (av. removals of 70% COD, 60% CODsol, 24% nitrogen, and 46% phosphorus). The biomass PAP was evaluated to be in excess of 0.4 gPHA/gVSS. Batch fermn. of full-scale WWTP sludge at selected temps. (35, 42 and 55 °C) produced centrate (6-9.4 gCODVFA/L) of consistent VFA compn., with optimal fermn. performance at 42 °C. Centrate was used to accumulate PHA up to 0.39 gPHA/gVSS. The centrate nutrients are a challenge to the accumulation process but producing a biomass with 0.5 gPHA/gVSS is considered to be realistically achievable within the typically available carbon flows at municipal waste management facilities.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhsVans7Y%253D&md5=139eac0ce5d09ef3d7176ea108ce1292
7. 7
  Bengtsson, S.; Karlsson, A.; Alexandersson, T.; Quadri, L.; Hjort, M.; Johansson, P.; Morgan-Sagastume, F.; Anterrieu, S.; Arcos-Hernandez, M.; Karabegovic, L.; Magnusson, P.; Werker, A. A process for polyhydroxyalkanoate (PHA) production from municipal wastewater treatment with biological carbon and nitrogen removal demonstrated at pilot-scale. New Biotechnol. 2017, 35, 42– 53, DOI: 10.1016/j.nbt.2016.11.005
  7
  A process for polyhydroxyalkanoate (PHA) production from municipal wastewater treatment with biological carbon and nitrogen removal demonstrated at pilot-scale
  Bengtsson, Simon; Karlsson, Anton; Alexandersson, Tomas; Quadri, Luca; Hjort, Markus; Johansson, Peter; Morgan-Sagastume, Fernando; Anterrieu, Simon; Arcos-Hernandez, Monica; Karabegovic, Lamija; Magnusson, Per; Werker, Alan
  New Biotechnology (2017), 35 (), 42-53CODEN: NBEIBR; ISSN:1871-6784. (Elsevier B.V.)
  A process was developed for biol. treatment of municipal wastewater for carbon and nitrogen removal while producing added-value polyhydroxyalkanoates (PHAs). The process comprised steps for pre-denitrification, nitrification and post-denitrification and included integrated fixed-film activated sludge (IFAS) with biofilm carrier media to support nitrification. In a pilot-scale demonstration (500-800 L), wastewater treatment performance, in line with European stds., were achieved for total COD (83% removal) and total nitrogen (80% removal) while producing a biomass that was able to accumulate up to 49% PHA of volatile suspended solids with acetic acid or fermented org. residues as substrates. Robust performance in wastewater treatment and enrichment of PHA-producing biomass was demonstrated under realistic conditions including influent variability during 225 days of operation. The IFAS system was found to be advantageous since maintaining nitrification on the biofilm allowed for a relatively low (2 days) solids retention time (SRT) for the suspended biomass in the bulk phase. Lower SRT has advantages in higher biomass yield and higher active fraction in the biomass which leads to higher PHA productivity and content. The outcomes show that prodn. of added-value biopolymers may be readily integrated with carbon and nitrogen removal from municipal wastewater.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XitFGnsbbM&md5=8bae4266f36650fc46e3330579400659
8. 8
  Jia, Q.; Xiong, H.; Wang, H.; Shi, H.; Sheng, X.; Sun, R.; Chen, G. Production of polyhydroxyalkanoates (PHA) by bacterial consortium from excess sludge fermentation liquid at laboratory and pilot scales. Bioresour. Technol. 2014, 171, 159– 167, DOI: 10.1016/j.biortech.2014.08.059
  8
  Production of polyhydroxyalkanoates (PHA) by bacterial consortium from excess sludge fermentation liquid at laboratory and pilot scales
  Jia, Qianqian; Xiong, Huilei; Wang, Hui; Shi, Hanchang; Sheng, Xinying; Sun, Run; Chen, Guoqiang
  Bioresource Technology (2014), 171 (), 159-167CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
  The generation of polyhydroxyalkanoates (PHA) from excess sludge fermn. liq. (SFL) was studied at lab and pilot scale. A PHA-accumulated bacterial consortium (S-150) was isolated from activated sludge using simulated SFL (S-SFL) contained high concn. volatile fatty acids (VFA) and nitrogen. The maximal PHA content accounted for 59.18% in S-SFL and dropped to 23.47% in actual SFL (L-SFL) of the dry cell wt. (DCW) at lab scale. The pilot-scale integrated system comprised an anaerobic fermn. reactor (AFR), a ceramic membrane system (CMS) and a PHA prodn. bio-reactor (PHAR). The PHA content from pilot-scale SFL (P-SFL) finally reached to 59.47% DCW with the maximal PHA yield coeff. (YP/S) of 0.17 gPHA/gCOD. The results indicated that VFA-contg. SFL was suitable for PHA prodn. The adverse impact of excess nitrogen and non-VFAs in SFL might be eliminated by pilot-scale domestication, which might resulted in community structure optimization and substrate selective ability improvement of S-150.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhsVKntr%252FO&md5=ab0f27b2dd414a3774b23afd680b8fa0
9. 9
  Chakravarty, P.; Mhaisalkar, V.; Chakrabarti, T. Study on polyhydroxyalkanoate (PHA) production in pilot scale continuous mode wastewater treatment system. Bioresour. Technol. 2010, 101, 2896– 2899, DOI: 10.1016/j.biortech.2009.11.097
  9
  Study on poly-hydroxyalkanoate (PHA) production in pilot scale continuous mode wastewater treatment system
  Chakravarty, Partha; Mhaisalkar, Vasant; Chakrabarti, Tapan
  Bioresource Technology (2010), 101 (8), 2896-2899CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
  Generation of polyhydroxyalkanoates (PHAs) from milk and ice-cream processing wastewater was studied in a continuous mode reactor system at pilot scale. The integrated system comprised an anaerobic acidogenic reactor (AAR), a conventional activated sludge prodn. reactor (ASPR) and a PHA synthesis reactor (PHAR) to induce PHA accumulation in the biomass which was finally harvested while treating the raw dairy wastewater to meet the disposal limits thereby reducing generation of disposable sludge. The PHA content in the PHA rich biomass was ∼43% of the sludge dry wt. Kinetics of both ASPR and PHAR were studied. The max. PHA yield coeff. (Ymaxsp) with respect to COD degrdn. in the PHAR was derived as 0.25 kg PHA/kg of COD degraded. Similarly, the kinetic parameters i.e. Ks, μm, Yobs and kd of the ASPR were 37.16 mg/l COD, 0.97 d-1, 0.51 mg MLSS/mg COD and 0.049 d-1, resp.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXjvVekuw%253D%253D&md5=3690860328d3ba6992ce15249099dabd
10. 10
  Tamis, J.; Luzkova, K.; Jiang, Y.; van Loosdrecht, M. C. M.; Kleerebezem, R. Enrichment of Plasticicumulans acidivorans at pilot-scale for PHA production on industrial wastewater. J. Biotechnol. 2014, 192, 161– 169, DOI: 10.1016/j.jbiotec.2014.10.022
  10
  Enrichment of Plasticicumulans acidivorans at pilot-scale for PHA production on industrial wastewater
  Tamis, Jelmer; Luzkov, Katlin; Jiang, Yang; Loosdrecht, Mark C. M. van; Kleerebezem, Robbert
  Journal of Biotechnology (2014), 192 (Part_A), 161-169CODEN: JBITD4; ISSN:0168-1656. (Elsevier B.V.)
  A PHA producing microbial culture dominated by Plasticicumulans acidivorans was enriched in a pilot plant using fermented wastewater from the Mars candy bar factory. The pilot plant comprised (1) anaerobic fermn., (2) enrichment of a PHA-producing microbial community and (3) accumulation for maximization of the cellular PHA content. After anaerobic fermn., the wastewater contained mainly VFAs (0.64 ± 0.15 gCOD/gCOD) and ethanol (0.22 ± 0.13 gCOD/gCOD). In the enrichment reactor (cycle 12 h, SRT 24 h) a feast-famine pattern was established with a feast phase of around 35 ± 5 min. The culture was able to accumulate 0.70 ± 0.05 gPHA/gVSS. The difference with previous lab-scale results from P. acidivorans, in which a PHA content of 0.90 gPHA/gVSS was achieved, could be attributed to the presence of solids in the influent, the growth of a side population and the accumulation of non-PHA storage compds. that appeared to be related to ethanol consumption.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhvVams7vP&md5=11e29e8e3815deea6ff2f191adb0a969
11. 11
  Reis, M. A. M.; Albuquerque, M. G. E.; Villano, M.; Majone, M. Mixed culture processes for polyhydroxyalkanoate production from agroindustrial surplus wastes as feedstocks. Comprehensive Biotechnology 2011, 669– 683, DOI: 10.1016/B978-0-08-088504-9.00464-5
  There is no corresponding record for this reference.
12. 12
  Pfaltzgraff, L. A.; De bruyn, M.; Cooper, E. C.; Budarin, V.; Clark, J. H. Food waste biomass: a resource for high-value chemicals. Green Chem. 2013, 15, 307, DOI: 10.1039/c2gc36978h
  12
  Food waste biomass: a resource for high-value chemicals
  Pfaltzgraff, Lucie A.; De Bruyn, Mario; Cooper, Emma C.; Budarin, Vitaly; Clark, James H.
  Green Chemistry (2013), 15 (2), 307-314CODEN: GRCHFJ; ISSN:1463-9262. (Royal Society of Chemistry)
  Our society currently faces the twin challenges of resource depletion and waste accumulation leading to rapidly escalating raw material costs and increasingly expensive and restrictive waste disposal legislation. The variety of food processes used in the food and drink industry globally generate food supply chain waste on a multi tonne scale every year. Such resides include wheat straw surpluses, spent coffee grounds or citrus peels, all of which represent a resource for an integrated, product focused biorefinery. Orange peel is particularly interesting: pectin and D-limonene, 2 marketable components, can be produced together with several flavonoids under the same conditions at a liter scale using low temp. microwave treatment. The running costs for such a process on large scale (50,000 metric tonnes/yr) have been estd. on the basis of the combined prodn. of pectin and D-limonene.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXhsVOntr4%253D&md5=b77036666de2e9ba9cb1c9c748f058a8
13. 13
  Valentino, F.; Gottardo, M.; Micolucci, F.; Pavan, P.; Bolzonella, D.; Rossetti, S.; Majone, M. Organic fraction of municipal solid waste recovery by conversion into added-value polyhydroxyalkanoates and biogas. ACS Sustainable Chem. Eng. 2018, 6, 16375– 16385, DOI: 10.1021/acssuschemeng.8b03454
  13
  Organic Fraction of Municipal Solid Waste Recovery by Conversion into Added-Value Polyhydroxyalkanoates and Biogas
  Valentino, Francesco; Gottardo, Marco; Micolucci, Federico; Pavan, Paolo; Bolzonella, David; Rossetti, Simona; Majone, Mauro
  ACS Sustainable Chemistry & Engineering (2018), 6 (12), 16375-16385CODEN: ASCECG; ISSN:2168-0485. (American Chemical Society)
  The integrated-multistage process proposed herein is a practical example of a biorefinery platform in which the org. fraction of municipal solid waste (OFMSW) is used as a valued source for polyhydroxyalkanoates (PHA) and biogas prodn. Tech. and economical feasibilities of this approach have been demonstrated at pilot-scale, providing a possible upgrade to traditional biowaste management practices, presently based on anaerobic digestion (AD). A pH-controlled OFMSW fermn. stage produced a liq. VFA-rich stream with a high VFA/CODSOL ratio (0.90 COD/COD) that was easily used in the following aerobic stages for biomass and PHA prodn. The solid fraction was valorized into biogas through AD, obtaining energy and minimizing secondary flux waste generation. The reliable biomass enrichment was demonstrated by a stable feast-famine regime and supported by microbial community anal. The selected consortium accumulated PHA up to 55% wt. Compared to the traditional AD process in an urban scenario of 900000 AE, the integrated approach for OFMSW valorization is preferable, and it is characterized by an elec. energy prodn. of 85.7 MWh/d and 1.976 t/d as PHA productivity. The proposed process was also evaluated as economically sustainable if the PHA is marketed from 0.90 euro/kg as the min. threshold to a higher market price.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhvFChsbzK&md5=66ce81b9e5afba63f17526c6fecaf082
14. 14
  Korkakaki, E.; Mulders, M.; Veeken, A.; Rozendal, R.; van Loosdrecht, M. C. M.; Kleerebezem, R. PHA production from the organic fraction of municipal solid waste (OFMSW): Overcoming the inhibitory matrix. Water Res. 2016, 96, 74– 83, DOI: 10.1016/j.watres.2016.03.033
  14
  PHA production from the organic fraction of municipal solid waste (OFMSW): Overcoming the inhibitory matrix
  Korkakaki, Emmanouela; Mulders, Michel; Veeken, Adrie; Rozendal, Rene; van Loosdrecht, Mark C. M.; Kleerebezem, Robbert
  Water Research (2016), 96 (), 74-83CODEN: WATRAG; ISSN:0043-1354. (Elsevier Ltd.)
  Leachate from the source sepd. org. fraction of municipal solid waste (OFMSW) was evaluated as a substrate for polyhydroxyalkanoates (PHA) prodn. Initially, the enrichment step was conducted directly on leachate in a feast-famine regime. Maximization of the cellular PHA content of the enriched biomass yielded to low PHA content (29 wt%), suggesting that the selection for PHA-producers was unsuccessful. When the substrate for the enrichment was switched to a synthetic volatile fatty acid (VFA) mixt. -resembling the VFA carbon compn. of the leachate-the PHA-producers gained the competitive advantage and dominated. Subsequent accumulation with leachate in nutrient excess conditions resulted in a max. PHA content of 78 wt%. Based on the exptl. results, enriching a PHA-producing community in a "clean" VFA stream, and then accumulating PHA from a stream that does not allow for enrichment but does enable a high cellular PHA content, such as OFMSW leachate, makes the overall process much more economically attractive. The estd. overall process yield can be increased four-fold, in comparison to direct use of the complex matrix for both enrichment and accumulation.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28Xls1Ggsro%253D&md5=5d8b04530373aab084436e9f859962a4
15. 15
  Colombo, B.; Favini, F.; Scaglia, B.; Sciarria, T. P.; D’Imporzano, G.; Pognani, M.; Alekseeva, A.; Eisele, G.; Cosentino, C.; Adani, F. Enhanced polyhydroxyalkanoate (PHA) production from the organic fraction of municipal solid waste by using mixed microbial culture. Biotechnol. Biofuels 2017, 10, 201, DOI: 10.1186/s13068-017-0888-8
  15
  Enhanced polyhydroxyalkanoate (PHA) production from the organic fraction of municipal solid waste by using mixed microbial culture
  Colombo, Bianca; Favini, Francesca; Scaglia, Barbara; Sciarria, Tommy Pepe; D'imporzano, Giuliana; Pognani, Michele; Alekseeva, Anna; Eisele, Giorgio; Cosentino, Cesare; Adani, Fabrizio
  Biotechnology for Biofuels (2017), 10 (), 201/1-201/15CODEN: BBIIFL; ISSN:1754-6834. (BioMed Central Ltd.)
  In Europe, almost 87.6 million tonnes of food waste are produced. Despite the high biol. value of food waste, traditional management solns. do not consider it as a precious resource. Many studies have reported the use of food waste for the prodn. of high added value mols. Polyhydroxyalkanoates (PHAs) represent a class of interesting bio-polyesters accumulated by different bacterial cells, and has been proposed for prodn. from the org. fraction of municipal solid waste (OFMSW). Nevertheless, until now, no attention has been paid to the entire biol. process leading to the transformation of food waste to org. acids (OA) and then to PHA, getting high PHA yield per food waste unit. In particular, the acid-generating process needs to be optimized, maximizing OA prodn. from OFMSW. To do so, a pilot-scale Anaerobic Percolation Biocell Reactor (100 L in vol.) was used to produce an OA-rich percolate from OFMSW which was used subsequently to produce PHA. The optimized acidogenic process resulted in an OA prodn. of 151 g kg-1 from fresh OFMSW. The subsequent optimization of PHA prodn. from OA gave a PHA prodn., on av., of 223 ± 28 g kg-1 total OA fed. Total mass balance indicated, for the best case studied, a PHA prodn. per OFMSW wt. unit of 33.22 ± 4.2 g kg-1 from fresh OFMSW, corresponding to 114.4 ± 14.5 g kg-1 of total solids from OFMSW. PHA compn. revealed a hydroxybutyrate/hydroxyvalerate (%) ratio of 53/47 and Mw of 8·105 kDa with a low polydispersity index, i.e. 1.4. This work showed how by optimizing acidic fermn. it could be possible to get a large amt. of OA from OFMSW to be then transformed into PHA. This step is important as it greatly affects the total final PHA yield. Data obtained in this work can be useful as the starting point for considering the economic feasibility of PHA prodn. from OFMSW by using mixed culture.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXitV2nsb7N&md5=3c5295c849bc49d91e474aebcd6fc8a2
16. 16
  Basset, N.; Katsou, E.; Frison, N.; Malamis, S.; Dosta, J.; Fatone, F. Integrating the selection of PHA storing biomass and nitrogen removal via nitrite in the main wastewater treatment line. Bioresour. Technol. 2016, 200, 820– 829, DOI: 10.1016/j.biortech.2015.10.063
  16
  Integrating the selection of PHA storing biomass and nitrogen removal via nitrite in the main wastewater treatment line
  Basset, N.; Katsou, E.; Frison, N.; Malamis, S.; Dosta, J.; Fatone, F.
  Bioresource Technology (2016), 200 (), 820-829CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
  A novel scheme was developed for the treatment of municipal wastewater integrating nitritation/denitritation with the selection of polyhydroxyalkanoates (PHA) storing biomass under an aerobic/anoxic, feast/famine regime. The process took place in a sequencing batch reactor (SBR) and the subsequent PHA accumulation in a batch reactor. The carbon source added during the selection and accumulation steps consisted of fermn. liq. from the org. fraction of municipal solids waste (OFMSW FL) (Period I) and OFMSW and primary sludge fermn. liq. (Period II). Selection of PHA storing biomass was successful and denitritation was driven by internally stored PHA during the famine phase. Under optimum conditions of SBR operation ammonia removal was 93%, reaching a max. nitrite removal of 98%. The treated effluent met the nitrogen limits, while PHA-storing biomass was successfully selected. The max. accumulation of PHA was 10.6% (wt.) since the nutrients present in the carbon source promoted bacterial growth.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhslegu7vI&md5=67bcf3d5afa2fbe454c2f19785c77c0e
17. 17
  Valentino, F.; Morgan-Sagastume, F.; Fraraccio, S.; Corsi, G.; Zanaroli, G.; Werker, A.; Majone, M. Sludge minimization in municipal wastewater treatment by polyhydroxyalkanoate (PHA) production. Environ. Sci. Pollut. Res. 2015, 22, 7281– 7294, DOI: 10.1007/s11356-014-3268-y
  17
  Sludge minimization in municipal wastewater treatment by polyhydroxyalkanoate (PHA) production
  Valentino, Francesco; Morgan-Sagastume, Fernando; Fraraccio, Serena; Corsi, Giovanna; Zanaroli, Giulio; Werker, Alan; Majone, Mauro
  Environmental Science and Pollution Research (2015), 22 (10), 7281-7294CODEN: ESPLEC; ISSN:0944-1344. (Springer)
  An innovative approach has been recently proposed in order to link polyhydroxyalkanoates (PHA) prodn. with sludge minimization in municipal wastewater treatment, where (1) a sequencing batch reactor (SBR) is used for the simultaneous municipal wastewater treatment and the selection/enrichment of biomass with storage ability and (2) the acidogenic fermn. of the primary sludge is used to produce a stream rich in volatile fatty acids (VFAs) as the carbon source for the following PHA accumulation stage. The reliability of the proposed process has been evaluated at lab scale by using substrate synthetic mixts. for both stages, simulating a low-strength municipal wastewater and the effluent from primary sludge fermn., resp. Six SBR runs were performed under the same operating conditions, each time starting from a new activated sludge inoculum. In every SBR run, despite the low VFA content (10 % COD, COD basis) of the substrate synthetic mixt., a stable feast-famine regime was established, ensuring the necessary selection/enrichment of the sludge and sol. COD removal to 89 %. A good process reproducibility was obsd., as also confirmed by denaturing gradient gel electrophoresis (DGGE) anal. of the microbial community, which showed that a high similarity after SBR steady-state had been reached. The main variation factors of the storage properties among different runs were uncontrolled changes of settling properties which in turn caused variations of both sludge retention time and specific org. loading rate. In the following accumulation batch tests, the selected/enriched consortium was able to accumulate PHA with good rate (63 mg CODPHA g CODXa-1 h-1) and yield (0.23 CODPHA CODΔS-1) in spite that the feeding soln. was different from the acclimation one. Even though the PHA prodn. performance still requires optimization, the proposed process has a good potential esp. if coupled to minimization of both primary sludge (by its use as the VFA source for the PHA accumulation, via previous fermn.) and excess secondary sludge (by its use as the biomass source for the PHA accumulation).
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhtFeru7vE&md5=c51d7526f28c36bea36f353e25c46c5c
18. 18
  Valentino, F.; Beccari, M.; Fraraccio, S.; Zanaroli, G.; Majone, M. Feed frequency in a Sequencing Batch Reactor strongly affects the production of polyhydroxyalkanoates (PHAs) from volatile fatty acids. New Biotechnol. 2014, 31, 264– 275, DOI: 10.1016/j.nbt.2013.10.006
  18
  Feed frequency in a sequencing batch reactor strongly affects the production of polyhydroxyalkanoates (PHAs) from volatile fatty acids
  Valentino, Francesco; Beccari, Mario; Fraraccio, Serena; Zanaroli, Giulio; Majone, Mauro
  New Biotechnology (2014), 31 (4), 264-275CODEN: NBEIBR; ISSN:1871-6784. (Elsevier B.V.)
  The prodn. of polyhydroxyalkanoates (PHAs) by activated sludge selected in a sequencing batch reactor (SBR) has been investigated. Several SBR runs were performed at the same applied org. load rate (OLR), hydraulic retention time (HRT) and feed concn. (8.5 g COD L-1 of volatile fatty acids, VFAs) under aerobic conditions. The effect of the feeding time was only evaluated with a cycle length of 8 h; for this particular cycle length, an increase in the storage response was obsd. by increasing the rate at which the substrate was fed into the reactor (at a fixed feeding frequency). Furthermore, a significantly stronger effect was obsd. by decreasing the cycle length from 8 h to 6 h and then to 2 h, changing the feed frequency or changing the org. load given per cycle (all of the other conditions remained the same): the length of the feast phase decreased from 26 to 20.0 and then to 19.7% of the overall cycle length, resp., due to an increase in the substrate removal rate. This removal rate was high and similar for the runs with cycle lengths of 2 h and 6 h in the SBR. This result was due to an increase in the selective pressure and the specific storage properties of the selected biomass. The highest polymer productivity after long-term accumulation batch tests was 1.7 g PHA L-1 d-1, with PHA content in the biomass of approx. 50% on a COD basis under nitrogen limitation. The DGGE profiles showed that the good storage performance correlated to the development of Lampropedia hyalina, which was only obsd. in the SBR runs characterized by a shorter cycle length.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXhsl2gsrvJ&md5=bde6cdacea0a7bb083c1e9908b21f9fd
19. 19
  Standard Methods for the Examination of Water and Wastewater, 20th ed.; American Public Health Association, 1998.
  There is no corresponding record for this reference.
20. 20
  Braunegg, G.; Sonnleitner, B.; Lafferty, R. M. A. Rapid gas chromatographic method for the determination of poly-b-hydroxybutyric acid in microbial biomass. Eur. J. Appl. Microbiol. 1978, 6, 29– 37, DOI: 10.1007/BF00500854
  20
  A rapid gas chromatographic method for the determination of poly-β-hydroxybutyric acid in microbial biomass
  Braunegg, G.; Sonnleitner, B.; Lafferty, R. M.
  European Journal of Applied Microbiology and Biotechnology (1978), 6 (1), 29-37CODEN: EJABDD; ISSN:0340-2118.
  The gas chromatog. method for the detn. of poly-β-hydroxybutyric acid (PHB) [26063-00-3] consists of a mild acid or alk. methanolysis of poly-β-hydroxybutyric acid directly without previous extn. of PHB from the cells; this is followed by gas chromatog. of the 3-hydroxybutyric acid Me ester. The method is characterized by high accuracy and excellent reproducibility, permitting detns. as low as 10-5 g/L. Only 4 h is required from sampling from the fermentor till completion of the PHB detn.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE1MXosFWruw%253D%253D&md5=db9baae8c3e1888aca113cb5cfdd0a2d
21. 21
  Valentino, F.; Brusca, A. A.; Beccari, M.; Nuzzo, A.; Zanaroli, G.; Majone, M. Start up of biological sequencing batch reactor (SBR) and short-term biomass acclimation for polyhydroxyalkanoates production. J. Chem. Technol. Biotechnol. 2013, 88, 261– 270, DOI: 10.1002/jctb.3824
  21
  Start up of biological sequencing batch reactor (SBR) and short-term biomass acclimation for polyhydroxyalkanoates production
  Valentino, Francesco; Brusca, Angelo Antonio; Beccari, Mario; Nuzzo, Andrea; Zanaroli, Giulio; Majone, Mauro
  Journal of Chemical Technology and Biotechnology (2013), 88 (2), 261-270CODEN: JCTBED; ISSN:0268-2575. (John Wiley & Sons Ltd.)
  The adaptation/selection of mixed microbial cultures under feast/famine conditions is an essential step for polyhydroxyalkanoates (PHA) prodn. This study investigated the short-term adaptation of a mixed microbial culture (activated sludge) during the start up of a sequencing batch reactor (SBR). Four different SBR runs were performed starting from different inocula and operated at the same org. load rate (8.5 gCOD L-1 d-1) and hydraulic retention time (1 day). At 3-7 days from SBR start up, the selected biomass was able to store PHA at comparable rate and yield with those obtained after long-term acclimation. Independently from the time passed, a short feast phase was the key parameter to obtain PHA storage at high rate and yield in the following accumulation stage (244 mgCOD g-1CODnonPolym h-1 for specific storage rate and 48% COD COD-1 as PHA content in the biomass). The DGGE profiles showed that the good storage performance and the structure of the microbial community were not fully correlated. CONCLUSIONS: The results suggest a new strategy for operating the PHA accumulation stage directly in the SBR, after very short biomass adaptation, instead of using two sep. reactors for biomass enrichment and PHA accumulation, resp. Copyright © 2012 Society of Chem. Industry.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmslKlt7Y%253D&md5=40a192b1ba88f4e94a1edcc60a524d65
22. 22
  Hao, J.; Wang, H. Volatile fatty acids productions by mesophilic and thermophilic sludge fermentation: Biological responses to fermentation temperature. Bioresour. Technol. 2015, 175, 367– 373, DOI: 10.1016/j.biortech.2014.10.106
  22
  Volatile fatty acids productions by mesophilic and thermophilic sludge fermentation: Biological responses to fermentation temperature
  Hao, Jiuxiao; Wang, Hui
  Bioresource Technology (2015), 175 (), 367-373CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
  The volatile fatty acids (VFAs) productions, as well as hydrolases activities, microbial communities, and homoacetogens, of mesophilic and thermophilic sludge anaerobic fermn. were investigated to reveal the microbial responses to different fermn. temps. Thermophilic fermn. led to 10-fold more accumulation of VFAs compared to mesophilic fermn. α-glucosidase and protease had much higher activities in thermophilic reactor, esp. protease. Illumina sequencing manifested that raising fermn. temp. increased the abundances of Clostridiaceae, Microthrixaceae and Thermotogaceae, which could facilitate either hydrolysis or acidification. Real-time PCR anal. demonstrated that under thermophilic condition the relative abundance of homoacetogens increased in batch tests and reached higher level at stable fermn., whereas under mesophilic condition it only increased slightly in batch tests. Therefore, higher fermn. temp. increased the activities of key hydrolases, raised the proportions of bacteria involved in hydrolysis and acidification, and promoted the relative abundance of homoacetogens, which all resulted in higher VFAs prodn.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhvVGgur3M&md5=2d352c6299cbaac265cf3b3607812394
23. 23
  Girotto, F.; Lavagnolo, M. C.; Pivato, A.; Cossu, R. Acidogenic fermentation of the organic fraction of municipal solid waste and cheese whey for bio-plastic precursors recovery – Effects of process conditions during batch tests. Waste Manage. 2017, 70, 71– 80, DOI: 10.1016/j.wasman.2017.09.015
  23
  Acidogenic fermentation of the organic fraction of municipal solid waste and cheese whey for bio-plastic precursors recovery - Effects of process conditions during batch tests
  Girotto, Francesca; Lavagnolo, Maria Cristina; Pivato, Alberto; Cossu, Raffaello
  Waste Management (Oxford, United Kingdom) (2017), 70 (), 71-80CODEN: WAMAE2; ISSN:0956-053X. (Elsevier Ltd.)
  The problem of fossil fuels dependency is being addressed through sustainable bio-fuels and bio-products prodn. worldwide. At the base of this bio-based economy there is the efficient use of biomass as non-virgin feedstock. Through acidogenic fermn., org. waste can be valorised in order to obtain several precursors to be used for bio-plastic prodn. Some investigations have been done but there is still a lack of knowledge that must be filled before moving to effective full scale plants. Acidogenic fermn. batch tests were performed using food waste (FW) and cheese whey (CW) as substrates. Effects of nine different combinations of substrate to inoculum (S/I) ratio (2, 4, and 6) and initial pH (5, 7, and 9) were investigated for metabolites (acetate, butyrate, propionate, valerate, lactate, and ethanol) productions. Results showed that the most abundant metabolites deriving from FW fermn. were butyrate and acetate, mainly influenced by the S/I ratio (acetate and butyrate max. productions of 21.4 and 34.5 g/L, resp., at S/I = 6). Instead, when dealing with CW, lactate was the dominant metabolite significantly correlated with pH (lactate max. prodn. of 15.7 g/L at pH = 9).
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFGgtbbL&md5=d14ba64e05f69b36cf2e3684f151911b
24. 24
  Bolzonella, D.; Fatone, F.; Pavan, P.; Cecchi, F. Anaerobic fermentation of organic fraction of municipal solid waste for the production of soluble organic compounds. Ind. Eng. Chem. Res. 2005, 44, 3412– 3418, DOI: 10.1021/ie048937m
  24
  Anaerobic Fermentation of Organic Municipal Solid Wastes for the Production of Soluble Organic Compounds
  Bolzonella, David; Fatone, Francesco; Pavan, Paolo; Cecchi, Franco
  Industrial & Engineering Chemistry Research (2005), 44 (10), 3412-3418CODEN: IECRED; ISSN:0888-5885. (American Chemical Society)
  After investigating the application of the mesophilic and thermophilic processes in completely stirred, batch, and plug-flow reactors, in this study the authors consider the anaerobic fermn. of source-sorted org. municipal solid wastes in psychrophilic conditions (14-22°) without pH control. The pilot-scale reactor was operated in a batch mode, with a hydraulic retention time of 4-4.5 d. The prodn. of sol. COD from the particulate matter was (on av.) 0.27 g COD per g of total volatile solids fed to the reactor when operating with a total solids content of 20-35 g/L. The volatile fatty acids (VFA) were 15% of the sol. COD produced after 4 d of reaction. These values are far lower than those found in mesophilic and thermophilic conditions, where the prodn. of sol. COD ranged from 0.5 up to 0.9 g COD/g TVSfed and volatile fatty acids could reach 90% of sol. COD. Further, the first-order reaction const. for the hydrolysis process, Kh, for the psychrophilic conditions was found equal to 0.11 d-1 at 20°, while it was in the range 0.2-0.4 d-1 when operating in mesophilic or thermophilic conditions. Conclusively, the study of the psychrophilic fermn. process allowed for completing the scenario of different options of anaerobic solid-state fermn. of org. waste. Though mesophilic and thermophilic processes resulted in being more effective in dissoln. of particulate matter, psychrophilic processes can be of some interest because they are simpler and energy saving. In particular, psychrophilic processes can be useful for the prodn. of rough sol. COD to be used, e.g., for sustaining the biol. nutrients removal processes in wastewater treatment.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXis1OgsLg%253D&md5=960c634b2349a290bc3defbadb22a4a6
25. 25
  Bengtsson, S.; Pisco, A. R.; Johansson, P.; Lemos, P. C.; Reis, M. A. M. Molecular weight and thermal properties of polyhydroxyalkanoates produced from fermented sugar molasses by open mixed cultures. J. Biotechnol. 2010, 147, 172– 179, DOI: 10.1016/j.jbiotec.2010.03.022
  25
  Molecular weight and thermal properties of polyhydroxyalkanoates produced from fermented sugar molasses by open mixed cultures
  Bengtsson, Simon; Pisco, Ana R.; Johansson, Peter; Lemos, Paulo C.; Reis, Maria A. M.
  Journal of Biotechnology (2010), 147 (3-4), 172-179CODEN: JBITD4; ISSN:0168-1656. (Elsevier B.V.)
  Polyhydroxyalkanoates (PHAs) produced from fermented molasses and synthetic feeds contg. single volatile fatty acids (VFAs) by an open mixed culture enriched in glycogen accumulating organisms (GAOs) were characterized with regards to mol. wt. and thermal properties. The polymer contained five types of monomers, namely 3-hydroxybutyrate, 3-hydroxy-2-methylbutyrate, 3-hydroxyvalerate, 3-hydroxy-2-methylvalerate and 3-hydroxyhexanoate in different ratios depending on the VFA compn. of the substrate. Polymers produced from fermented molasses had wt. av. mol. wts. (Mw) in the range (3.5-4.3) × 105 g/mol and polydispersity indexes (PDI) of 1.8-2.1 while polymers produced from synthetic VFAs had Mw of (4.5-9.0) × 105 g/mol and PDI of 1.7-3.9. Thermal properties such as glass transition temp. (-14 °C to 4.8 °C), melting temp. (89-174 °C) and melting enthalpy (0-82.1 J/g) were controlled in broad ranges by the monomer compn. The decompn. temps. of the polymers produced were between 277.2 °C and 294.9 °C, and independent of monomer compn. and mol. wt.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXntVemu7o%253D&md5=ca4dc0cfef36e81a81ee31a666fe4c4f
26. 26
  Pittmann, T.; Steinmetz, H. Polyhydroxyalkanoate production on waste water treatment plants: process scheme, operating conditions and potential analysis for german and european municipal waste water treatment plants. Bioengineering 2017, 4, 54, DOI: 10.3390/bioengineering4020054
  There is no corresponding record for this reference.
27. 27
  Campanari, S.; e Silva, F. A.; Bertin, L.; Villano, M.; Majone, M. Effect of the organic loading rate on the production of polyhydroxyalkanoates in a multi-stage process aimed at the valorization of olive oil mill wastewater. Int. J. Biol. Macromol. 2014, 71, 34– 41, DOI: 10.1016/j.ijbiomac.2014.06.006
  27
  Effect of the organic loading rate on the production of polyhydroxyalkanoates in a multi-stage process aimed at the valorization of olive oil mill wastewater
  Campanari, Sabrina; e Silva, Francisca A.; Bertin, Lorenzo; Villano, Marianna; Majone, Mauro
  International Journal of Biological Macromolecules (2014), 71 (), 34-41CODEN: IJBMDR; ISSN:0141-8130. (Elsevier B.V.)
  Mixed microbial culture polyhydroxyalkanoates (PHA) prodn. has been investigated by using olive oil mill wastewater (OMW) as no-cost feedstock in a multi-stage process, also involving phenols removal and recovery. The selection of PHA-storing microorganisms occurred in a sequencing batch reactor (SBR), fed with dephenolized and fermented OMW and operated at different org. loading rates (OLR), ranging from 2.40 to 8.40 gCOD/L d. The optimal operating condition was obsd. at an OLR of 4.70 gCOD/L d, which showed the highest values of storage rate and yield (339 ± 48 mgCOD/gCOD h and 0.56 ± 0.05 COD/COD, resp.). The OLR applied to the SBR largely affected the performance of the PHA-accumulating reactor, which was fed through multiple pulsed addns. of pretreated OMW. From an overall mass balance, involving all the stages of the process, an abatement of about 85% of the OMW initial COD (COD) was estd. whereas the conversion of the influent COD into PHA was about 10% (or 22% by taking into account only the COD contained in the pretreated OMW, which is directly fed to the PHA prodn. stages). Overall, polymer volumetric productivity (calcd. from the combination of both the SBR and the accumulation reactor) accounted for 1.50 gPHA/L d.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXht1ags73N&md5=ff144388feec0f5a9c28bdef58724e83
28. 28
  Dionisi, D.; Majone, M.; Papa, V.; Beccari, M. Biodegradable polymers from organic acids by using activated sludge enriched by aerobic periodic feeding. Biotechnol. Bioeng. 2004, 85, 569– 579, DOI: 10.1002/bit.10910
  28
  Biodegradable polymers from organic acids by using activated sludge enriched by aerobic periodic feeding
  Dionisi, Davide; Majone, Mauro; Papa, Viviana; Beccari, Mario
  Biotechnology and Bioengineering (2004), 85 (6), 569-579CODEN: BIBIAU; ISSN:0006-3592. (John Wiley & Sons, Inc.)
  This article describes a process for the prodn. of biopolymers (polyhydroxyalkanoates, PHAs) based on the aerobic enrichment of activated sludge to obtain mixed cultures able to store PHAs at high rates and yields. Enrichment was obtained through the selective pressure established by feeding the C source in a periodic mode (feast and famine regime) in a sequencing batch reactor. A concd. mixt. of acetic, lactic, and propionic acids (overall concn. of 8.5 g COD/L) was fed every 2 h at 1/day overall diln. rate. Even at such high org. load (8.5 g COD/L-day), the selective pressure due to periodic feeding was effective in obtaining a biomass with a storage ability much higher than activated sludges. The immediate biomass response to substrate excess (as detd. thorough short-term batch tests) was characterized by a storage rate and yield of 649 mg PHA (as COD) g biomass (as COD)-1 h-1 and 0.45 mg PHA (as COD) mg removed substrates (as COD-1), resp. When the substrate excess was present for >2 h (long-term batch tests), the storage rate and yield decreased, whereas growth rate and yield significantly increased due to biomass adaptation. A max. polymer fraction in the biomass was therefore obtained at ∼50% (on COD basis). As for the PHA compn., the copolymer poly(β-hydroxybutyrate/β-hydroxyvalerate) with 31% of hydroxyvalerate monomer was produced from the substrate mixt. Comparison of the tests with individual and mixed substrates seemed to indicate that, on removing the substrate mixt. for copolymer prodn., propionic acid was fully utilized to produce propionylCoA, whereas the acetylCoA was fully provided by acetic and lactic acid.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXhvFektrg%253D&md5=78541ffc37180f2db21541d656329af1
29. 29
  Albuquerque, M. G. E.; Torres, C. A. V.; Reis, M. A. M. Polyhydroxyalkanoates (PHA) production by a mixed microbial culture using sugar molasses: effect of the influent substrate concentration on culture selection. Water Res. 2010, 44, 3419– 3433, DOI: 10.1016/j.watres.2010.03.021
  29
  Polyhydroxyalkanoate (PHA) production by a mixed microbial culture using sugar molasses: Effect of the influent substrate concentration on culture selection
  Albuquerque, M. G. E.; Torres, C. A. V.; Reis, M. A. M.
  Water Research (2010), 44 (11), 3419-3433CODEN: WATRAG; ISSN:0043-1354. (Elsevier B.V.)
  In Polyhydroxyalkanoate (PHA) prodn. processes using Mixed Microbial Culture (MMC), the success of the culture selection step dets., to a great extent, the PHA accumulation performance obtained in the final PHA prodn. stage. In this study, the effect of the influent substrate concn. (30-60 Cmmol VFA/L) on the selection of a PHA-storing culture using a complex feedstock, fermented sugar molasses, was assessed. At 30 and 45 Cmmol VFA/L, substrate concn. impacted on the process kinetics through a substrate dependent kinetic limitation effect. However, further increasing the carbon substrate concn. to 60 Cmmol VFA/L, resulted in an unforeseen growth limitation effect assocd. with a micronutrient deficiency of the fermented feedstock (magnesium) and high operating pH. Struvite pptn. caused a nutrient limitation which prevented biomass concn. increase, thus causing the feast to famine length ratio to vary in the selection reactor, with subsequent impact on the selective pressure for PHA-storing organisms. A highly dynamic response of the selected population to transient conditions of feast to famine ratio, in the range of 0.21-1.1, was obsd. Kinetic (limiting concn. of carbon source) and physiol. (loss of internal growth limitation due to the shorter length of famine phase) effects, resulting from variation of the influent substrate concn., were subsequently demonstrated in batch studies. The culture selected at an influent substrate concn. of 45 Cmmol VFA/L showed the best PHA-storing capacity since neither substrate concn. nor feast to famine ratio were limiting factors. This culture, highly enriched in PHA-storing organisms (88%), reached a max. PHA content of 74.6%.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXmtlKhur8%253D&md5=6a686a80ffaafb558c056f4ccd234949
30. 30
  Majone, M.; Massanisso, P.; Carucci, A.; Lindrea, K.; Tandoi, V. Influence of storage on kinetic selection to control aerobic filamentous bulking. Water Sci. Technol. 1996, 34, 223– 232, DOI: 10.2166/wst.1996.0554
  30
  Influence of storage on kinetic selection to control aerobic filamentous bulking
  Majone, M.; Massanisso, P.; Carucci, A.; Lindrea, K.; Tandoi, V.
  Water Science and Technology (1996), 34 (5-6, Water Quality International '96, Part 3), 223-232CODEN: WSTED4; ISSN:0273-1223. (Elsevier)
  In various activated sludge systems, sludge grows under transient (unbalanced) conditions and storage of internal polymers becomes important. Differences in storage capacity under transients are often used to explain kinetic control of bulking, but storage is neither studied in detail nor usually included in modeling. For this reason, the transient response of different aerobic mixed cultures was studied by exptl. detg. the role of storage. Two different mixed cultures (bulking and non-bulking) were selected in an acetate-limited medium, by continuous or intermittent feeding of a CSTR, resp. Batch tests were used to investigate the transient response of the selected cultures as a function of the starvation time and of the ratio of the initial concn. of the substrate and sludge biomass (So/Xo). In most exptl. conditions, both cultures showed that the storage of polyhydroxybutyrate (PHB) is in general the prevailing mechanism of substrate removal. In particular, the culture dominated by floc-formers showed very fast response to the substrate spike with a high obsd. yield. Storage was practically the only metab. occurring. The ratio So/Xo did not have a major role in detg. the type and extent of the response. Starvation did not affect the response of the floc-formers to transient conditions. For the filamentous bacteria, both the growth response and, even more significantly, the storage response were neg. affected. Hence, the difference in storage capacity between filamentous and floc-forming bacteria was further increased.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK28XnsFOrsLs%253D&md5=fd6c600d855da23ef031310fbb0e94a7
31. 31
  Albuquerque, M. G. E.; Eiroa, M.; Torres, C.; Nunes, B. R.; Reis, M. A. M. Strategies for the development of a side stream process for polyhydroxyalkanoate (PHA) production from sugar cane molasses. J. Biotechnol. 2007, 130, 411– 421, DOI: 10.1016/j.jbiotec.2007.05.011
  31
  Strategies for the development of a side stream process for polyhydroxyalkanoate (PHA) production from sugar cane molasses
  Albuquerque, M. G. E.; Eiroa, M.; Torres, C.; Nunes, B. R.; Reis, M. A. M.
  Journal of Biotechnology (2007), 130 (4), 411-421CODEN: JBITD4; ISSN:0168-1656. (Elsevier B.V.)
  A three-stage process was developed to produce polyhydroxyalkanoates (PHAs) from sugar cane molasses. The process includes (1) molasses acidogenic fermn., (2) selection of PHA-accumulating cultures, (3) PHA batch accumulation using the enriched sludge and fermented molasses. In the fermn. step, the effect of pH (5-7) on the org. acids profile and productivity was evaluated. At higher pH, acetic and propionic acids were the main products, while lower pH favored the prodn. of butyric and valeric acids. PHA accumulation using fermented molasses was evaluated with two cultures selected either with acetate or fermented molasses. The effect of org. acids distribution on polymer compn. and yield was evaluated with the acetate selected culture. Storage yields varied from 0.37 to 0.50 Cmmol HA/Cmmol VFA. A direct relationship between the type of org. acids used and the polymers compn. was obsd. Low ammonia concn. (0.1 Nmmol/l) in the fermented molasses stimulated PHA storage (0.62 Cmmol HA/Cmmol VFA). In addn., strategies of reactor operation to select a PHA-accumulating culture on fermented molasses were developed. The combination of low org. loading with high ammonia concn. selected a culture with a stable storage capacity and with a storage yield (0.59 Cmmol HA/Cmmol VFA) similar to that of the acetate-selected culture.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXnsFKgsb0%253D&md5=eb8c5b8ee714eacc8f3d7979c5ff9f8a
32. 32
  Valentino, F.; Karabegovic, L.; Majone, M.; Morgan-Sagastume, F.; Werker, A. Polyhydroxyalkanoate (PHA) storage within a mixed-culture biomass with simultaneous growth as a function of accumulation substrate nitrogen and phosphorus levels. Water Res. 2015, 77, 49– 63, DOI: 10.1016/j.watres.2015.03.016
  32
  Polyhydroxyalkanoate (PHA) storage within a mixed-culture biomass with simultaneous growth as a function of accumulation substrate nitrogen and phosphorus levels
  Valentino, Francesco; Karabegovic, Lamija; Majone, Mauro; Morgan-Sagastume, Fernando; Werker, Alan
  Water Research (2015), 77 (), 49-63CODEN: WATRAG; ISSN:0043-1354. (Elsevier Ltd.)
  The response of a mixed-microbial-culture (MMC) biomass for PHA accumulation was evaluated over a range of relative nitrogen (N) and phosphorus (P) availabilities with respect to the supply of either complex (fermented whey permeate - FWP) or simpler (acetic acid) org. feedstocks. Fed-batch feed-on-demand PHA accumulation expts. were conducted where the feed N/COD and P/COD ratios were varied ranging from conditions of nutrient starvation to excess. A feast-famine enrichment (activated sludge) biomass, produced in a pilot-scale aerobic sequencing batch reactor on FWP and with a long history of stable PHA accumulation performance, was used for all the expts. as ref. material. FWP with N/COD ratios of (2, 5, 15, 70 mg/g all with P/COD = 8 mg/g) as well as simulated FWP with nutrient starvation (N/COD = P/COD = 0) conditions were applied. For the acetic acid accumulations, nutrient starvation as well as N/COD variations (2.5, 5, 50 mg/g all with P/COD = 9 mg/g) and P/COD variations (0.5, 2, 9, 15 mg/g all with N/COD = 10 mg/g) were evaluated. An optimal range of combined N and P limitation with N/COD from 2 to 15 mg/g and P/COD from 0.5 to 3 mg/g was considered to offer consistent improvement of productivity over the case of nutrient starvation. Productivity increased due to active biomass growth of the PHA storing biomass without obsd. risk for a growth response overtaking PHA storage activity. PHA prodn. with respect to the initial active biomass was significantly higher even in cases of excess nutrient addns. when compared to the cases of nutrient starvation. The 24-h PHA productivities were enhanced as much as 4-fold from a base value of 1.35 g-PHA per g initial active biomass with respect nutrient starvation feedstock. With or without nutrient loading the biomass consistently accumulated similar and significant PHA (nominally 60% g-PHA/g-VSS). Based on results from replicate expts. some variability in the extant biomass max. PHA content was attributed to interpreted differences in the biomass initial physiol. state and not due to changes in feedstock nutrient loading. We found that the accumulation process prodn. rates for mixed cultures can be sustained long after the max. PHA content of the biomass was reached. Within the specific context of the applied fed-batch feed-on-demand methods, active biomass growth was interpreted to have been largely restricted to the PHA-storing phenotypic fraction of the biomass. This study suggests practical prospects for mixed culture PHA prodn. using a wide range of volatile fatty acid (VFA) rich feedstocks. Such VFA sources derived from residual industrial or municipal org. wastes often naturally contain assocd. nutrients ranging in levels from limitation to excess.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXlsFeqsbw%253D&md5=48c1b6127e1a67e236ed39bc9c9222a9
33. 33
  Morgan-Sagastume, F.; Valentino, F.; Hjort, M.; Zanaroli, G.; Majone, M.; Werker, A. Acclimation process for enhancing polyhydroxyalkanoate accumulation in activated-sludge biomass. Waste Biomass Valorization 2019, 10, 1065– 1082, DOI: 10.1007/s12649-017-0122-8
  33
  Acclimation Process for Enhancing Polyhydroxyalkanoate Accumulation in Activated-Sludge Biomass
  Morgan-Sagastume, Fernando; Valentino, Francesco; Hjort, Markus; Zanaroli, Giulio; Majone, Mauro; Werker, Alan
  Waste and Biomass Valorization (2019), 10 (4), 1065-1082CODEN: WBVAAG; ISSN:1877-2641. (Springer)
  A strategy was evaluated for conditioning activated sludge biomass to a new substrate whereby the polyhydroxyalkanoate (PHA) accumulation capacity of the biomass was enhanced based on a series of aerobic feast-famine acclimation cycles applied prior to PHA accumulation. Different biomass types enriched during the treatment of municipal wastewater at lab., pilot, and full scales were exposed to aerobic feast-famine acclimation cycles at different feast-to-famine ratios with an acetate-propionate mixt. (lab. scale), acetate (pilot scale), and fermented waste-sludge centrate (pilot scale). A sevenfold increase in specific PHA storage rates and 20% increase in substrate utilization rates were obsd. during acclimation cycles (lab. acetate-propionate). Biomass acclimation led to more than doubling of the specific substrate utilization rates, PHA storage rates, biomass PHA contents, and specific PHA productivities (per initial biomass) during PHA accumulation. The biomass PHA contents were found to increase due to acclimation from 0.19 to 0.34 (lab. acetate-propionate), 0.39 to 0.46 (pilot acetate) and 0.19 to 0.25 gPHA/gVSS (pilot centrate). A similar bacterial community structure during acclimation indicated that a physiol. rather than a genotypic adaptation occurred in the biomass. The physiol. state of the biomass at the start of PHA accumulation was deemed significant in the subsequent PHA-accumulation performance. Pos. acclimation trends can be monitored by measuring the relative increase in feast substrate utilization or respiration rates with respect to those of the first acclimation cycle.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsl2murvE&md5=56c42a11f8f6bbda1ba157abb55a0969
34. 34
  Amulya, K.; Jukuri, S.; Venkata Mohan, S. Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling. Bioresour. Technol. 2015, 188, 231– 239, DOI: 10.1016/j.biortech.2015.01.070
  34
  Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling
  Amulya, K.; Jukuri, Srinivas; Venkata Mohan, S.
  Bioresource Technology (2015), 188 (), 231-239CODEN: BIRTEB; ISSN:0960-8524. (Elsevier Ltd.)
  Polyhydroxyalkanoates (PHA) prodn. was evaluated in a multistage operation using food waste as a renewable feedstock. The first step involved the prodn. of bio-hydrogen (bio-H2) via acidogenic fermn. Volatile fatty acid (VFA) rich effluent from bio-H2 reactor was subsequently used for PHA prodn., which was carried out in two stages, Stage II (culture enrichment) and Stage III (PHA prodn.). PHA-storing microorganisms were enriched in a sequencing batch reactor (SBR), operated at two different cycle lengths (CL-24; CL-12). Higher polymer recovery as well as VFA removal was achieved in CL-12 operation both in Stage II (16.3% dry cell wt. (DCW); VFA removal, 84%) and Stage III (23.7% DCW; VFA removal, 88%). The PHA obtained was a co-polymer [P(3HB-co-3HV)] of PHB and PHV. The results obtained indicate that this integrated multistage process offers new opportunities to further leverage large scale PHA prodn. with simultaneous waste remediation in the framework of biorefinery.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhvVCjtro%253D&md5=782d175b055534d6dd451623826729df
35. 35
  Moretto, G., Ardolino, F., Piasentin, A., Girotto, L., Cecchi, F. Integrated anaerobic codigestion system for the organic fraction of municipal solid waste and sewage sludge treatment: an Italian case study. J. Chem. Technol. Biotechnol. 2019, DOI: 10.1002/jctb.5993 .
  There is no corresponding record for this reference.
36. 36
  Valentino, F.; Moretto, G.; Gottardo, M.; Pavan, P.; Bolzonella, D.; Majone, M. Novel routes for urban bio-waste management: A combined acidic fermentation and anaerobic digestion process for platform chemicals and biogas production. J. Cleaner Prod. 2019, 220, 368– 375, DOI: 10.1016/j.jclepro.2019.02.102
  36
  Novel routes for urban bio-waste management: A combined acidic fermentation and anaerobic digestion process for platform chemicals and biogas production
  Valentino, Francesco; Moretto, Giulia; Gottardo, Marco; Pavan, Paolo; Bolzonella, David; Majone, Mauro
  Journal of Cleaner Production (2019), 220 (), 368-375CODEN: JCROE8; ISSN:0959-6526. (Elsevier Ltd.)
  A combined acidic fermn. and anaerobic digestion (AD) treatment has been developed on pilot scale for urban bio-waste conversion into volatile fatty acid (VFA) and biogas. The specific waste mixt. was composed by the pre-treated org. fraction of municipal solid waste (OFMSW) and waste activated sludge (WAS), both produced inside the Treviso (northeast Italy) municipality. The effect of temp. (37 °C and 55 °C) was investigated in both steps. Only the mesophilic fermn. process provided a VFA-rich stream (19.5 g CODVFA/L) with stable phys.-chem. features, with no need of chems. addn. for pH control. The sludge buffering capacity made this step tech. feasible. The AD step was performed on the solid-rich fraction of fermented bio-waste, after diln. with excess WAS. No relevant differences were obsd. under the two investigated temp.: in the steady state (org. loading rate of 2.5 kg VS/m3 d), the specific biogas prodn. was 0.40 and 0.45 m3/kg VS at 37 °C and 55 °C resp., with similar CH4 content (63-64% vol./vol.). The scaled-up version of the system (in an av. urban municipality of 170,000 Person Equiv.) revealed that the whole process is thermally sustainable if both reactors are operated at mesophilic temp.: 36% of surplus thermal energy and 13,03 MWh/d of produced electricity, which corresponds to a revenue of 609,605 euro/yr. In addn., 2,262 kg CODVFA/d are available for parallel purposes, such as the synthesis of bio-products with higher added value than bio-methane (e.g. biopolymers).
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXjs1Oqt78%253D&md5=92be45b65b4d98da3577900ccb2c3e2c

Pilot-Scale Polyhydroxyalkanoate Production from Combined Treatment of Organic Fraction of Municipal Solid Waste and Sewage SludgeClick to copy article linkArticle link copied!

Industrial & Engineering Chemistry Research

Abstract

1. Introduction

2. Materials and Methods

2.1. Pilot Plant Experimental Platform

Figure 1

2.1.1. Sewage Sludge (SS) and Organic Fraction of Municipal Solid Waste (OFMSW) Collection

2.1.2. Pilot Units

2.2. Sampling and Analytical Methods

2.3. Calculations

3. Results and Discussion

3.1. Fermentation of Feedstock for PHA Production

Figure 2

3.2. Biomass Selection/Enrichment under Aerobic Dynamic Feeding

Figure 3

3.3. PHA Accumulation

Figure 4

3.4. Overall PHA Yield and Possible Future Perspective

Figure 5

4. Conclusions

Author Information

Acknowledgments

References

Cited By

Industrial & Engineering Chemistry Research

Article Views

Altmetric

Citations

Recommended Articles

Abstract

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

References

Pilot-Scale Polyhydroxyalkanoate Production from Combined Treatment of Organic Fraction of Municipal Solid Waste and Sewage Sludge
Click to copy article linkArticle link copied!