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Reviews

Biologically Active Vitamin B12 Compounds in Foods for Preventing Deficiency among Vegetarians and Elderly Subjects
Fumio Watanabe *- ,
Yukinori Yabuta - ,
Yuri Tanioka - , and
Tomohiro Bito
The usual dietary sources of vitamin B12 are animal-source based foods, including meat, milk, eggs, fish, and shellfish, although a few plant-based foods such as certain types of dried lavers (nori) and mushrooms contain substantial and considerable amounts of vitamin B12, respectively. Unexpectedly, detailed characterization of vitamin B12 compounds in foods reveals the presence of various corrinoids that are inactive in humans. The majority of edible blue-green algae (cyanobacteria) and certain edible shellfish predominately contain an inactive corrinoid known as pseudovitamin B12. Various factors affect the bioactivity of vitamin B12 in foods. For example, vitamin B12 is partially degraded and loses its biological activity during cooking and storage of foods. The intrinsic factor-mediated gastrointestinal absorption system in humans has evolved to selectively absorb active vitamin B12 from naturally occurring vitamin B12 compounds, including its degradation products and inactive corrinoids that are present in daily meal foods. The objective of this review is to present up-to-date information on various factors that can affect the bioactivity of vitamin B12 in foods. To prevent vitamin B12 deficiency in high-risk populations such as vegetarians and elderly subjects, it is necessary to identify plant-source foods that contain high levels of bioactive vitamin B12 and, in conjunction, to prepare the use of crystalline vitamin B12-fortified foods.
Agricultural and Environmental Chemistry

Molecular Docking and QSAR Studies: Noncovalent Interaction between Acephate Analogous and the Receptor Site of Human Acetylcholinesterase
Khodayar Gholivand *- ,
Ali Asghar Ebrahimi Valmoozi - ,
Hamid R. Mahzouni - ,
Saied Ghadimi - , and
Rayhaneh Rahimi
Twelve new compounds of acephate (Ace) analogues were synthesized and characterized by 31P, 13C, and 1H NMR and IR spectroscopy. The probable insecticide potential of these compounds as well as 23 previously prepared molecules with a general skeleton of RC(O)–NH–P(O)X1X2 was predicted by PASS software. Docking analysis showed that hydrophobic interaction and hydrogen bonding were created between the functional groups of Ace derivatives and the receptor sites of acetylcholinesterase. PCA–QSAR indicated that the electronic descriptors are dominated in comparison with the structural descriptors. The experimental–QSAR (R2 = 0.903 and VIF < 2.997) and DFT–QSAR (R2 = 0.990 and VIF ≤ 10) models clarified that the net charge of functional groups contributes an important function in an inhibition mechanism. Validity and integrity of this model were confirmed by the LOO cross-validation method with q2 = 0.940 and low residuals between the training and testing sets. The correlation matrix of DFT–QSAR model confirmed the molecular docking results.

Identification of Orfamide A as an Insecticidal Metabolite Produced by Pseudomonas protegens F6
Ja Yeong Jang - ,
Si Young Yang - ,
Young Cheol Kim - ,
Chul Won Lee - ,
Myung Soo Park - ,
Jin Cheol Kim - , and
In Seon Kim *
The use of biosurfactants for agricultural crop protection has been gaining interest because they are generally biodegradable and environmentally friendly. In the present study, we identified an insecticidal biosurfactant produced by Pseudomonas protegens F6 (F6) and examined its use for aphid control. The growth of F6 was accompanied by increased aphid mortality and decreased water surface tension. Bioassay-guided chromatography coupled with instrumental analyses, nuclear magnetic resonance (NMR), and time-of-flight mass spectrometer (TOF MS) identified orfamide A as a major metabolite that showed insecticidal activity against green peach aphid (Myzus persicae). Orfamide A revealed a dose-dependent mortality against aphids, producing a LC50 value at 34.5 μg/mL, and caused a considerable decrease in the surface tension value of water, giving about 35.7 mN/m at 10 μg/mL. Laboratory and greenhouse mortality bioassays suggested that orfamide A may be applicable to control aphids in organic agriculture. This is the first report of orfamide A as an insecticidal metabolite against Myzus persicae.

Synthesis and Evaluation of Effective Inhibitors of Plant δ1-Pyrroline-5-carboxylate Reductase
Giuseppe Forlani *- ,
Łukasz Berlicki - ,
Mattia Duò - ,
Gabriela Dziędzioła - ,
Samuele Giberti - ,
Michele Bertazzini - , and
Paweł Kafarski
Analogues of previously studied phenyl-substituted aminomethylene-bisphosphonic acids were synthesized and evaluated as inhibitors of Arabidopsis thaliana δ1-pyrroline-5-carboxylate reductase. With the aim of improving their effectiveness, two main modifications were introduced into the inhibitory scaffold: the aminomethylenebisphosphonic moiety was replaced with a hydroxymethylenebisphosphonic group, and the length of the molecule was increased by replacing the methylene linker with an ethylidene chain. In addition, chlorine atoms in the phenyl ring were replaced with various other substituents. Most of the studied derivatives showed activity in the micromolar to millimolar range, with two of them being more effective than the lead compound, with concentrations inhibiting 50% of enzyme activity as low as 50 μM. Experimental evidence supporting the ability of these inhibitors to interfere with proline synthesis in vivo is also shown.

Soil Metabolism of [14C]Methiozolin under Aerobic and Anaerobic Flooded Conditions
Ki-Hwan Hwang - ,
Jong-Soo Lim - ,
Sung-Hun Kim - ,
Hee-Ra Chang - ,
Kyun Kim - ,
Suk-Jin Koo - , and
Jeong-Han Kim *
Methiozolin is a new turf herbicide controlling annual bluegrass in various cool- and warm-season turfgrasses. This study was conducted to investigate the fate of methiozolin in soil under aerobic and anaerobic flooded conditions using two radiolabeled tracers, [benzyl-14C]- and [isoxazole-14C]methiozolin. The mass balance of applied radioactivity ranged from 91.7 to 104.5% in both soil conditions. In the soil under the aerobic condition, [14C]methiozolin degraded with time to remain by 17.9 and 15.9% of the applied in soil at 120 days after treatment (DAT). [14C]Carbon dioxide and the nonextractable radioactivity increased as the soil aged to reach up to 41.5 and 35.7% for [benzyl-14C]methiozolin at 120 DAT, respectively, but 36.1 and 39.8% for [isoxazole-14C]methiozolin, respectively, during the same period. The nonextractable residue was associated more with humin and fulvic acid fractions under the aerobic condition. No significant volatile products or metabolites were detected during this study. The half-life of [14C]methiozolin was approximately 49 days in the soil under the aerobic condition; however, it could not be estimated in the soil under the anaerobic flooded condition because [14C]methiozolin degradation was limited. On the basis of these results, methiozolin is considered to undergo fast degradation by aerobic microbes, but not by anaerobic microbes in soil.
Analytical Methods

HPLC Determination of Isoflavone Levels in Osage Orange from the Midwest and Southern United States
Ketur Darji - ,
Cristina Miglis - ,
Ashley Wardlow - , and
Ehab A. Abourashed *
The fruit of the Maclura pomifera tree is a sustainable source for the pharmacologically interesting isoflavones, osajin and pomiferin. A reversed-phase HPLC method was developed to identify osage orange samples with high isoflavone content and to determine the optimum conditions for sample preparation. Analytical run time was 8 min at a flow rate of 1 mL/min using a gradient of acetonitrile in H2O (0.1% formic acid) and UV peak detection at 274 nm. The method was validated for specificity, accuracy, precision, and limits of detection and quantitation (LOD/LOQ). The method was applied to determine the levels of osajin and pomiferin in extracts prepared from different samples of osage orange growing in the Midwest and southern United States. Results demonstrated the effect of different variables, such as sample preparation, geographical location, and growth stage, on the levels of osajin and pomiferin in analyzed samples.

Preliminary Studies of Bio-oil from Fast Pyrolysis of Coconut Fibers
Tarciana M. Almeida - ,
Mozart D. Bispo - ,
Anne R. T. Cardoso - ,
Marcelo V. Migliorini - ,
Tiago Schena - ,
Maria Cecilia V. de Campos - ,
Maria Elisabete Machado - ,
Jorge A. López - ,
Laiza C. Krause - , and
Elina B. Caramão *
This work studied fast pyrolysis as a way to use the residual fiber obtained from the shells of coconut (Cocos nucifera L. var. Dwarf, from Aracaju, northeastern Brazil). The bio-oil produced by fast pyrolysis and the aqueous phase (formed during the pyrolysis) were characterized by GC/qMS and GC×GC/TOF-MS. Many oxygenated compounds such as phenols, aldehydes, and ketones were identified in the extracts obtained in both phases, with a high predominance of phenolic compounds, mainly alkylphenols. Eighty-one compounds were identified in the bio-oil and 42 in the aqueous phase using GC/qMS, and 95 and 68 in the same samples were identified by GC×GC/TOF-MS. The better performance of GC×GC/TOF-MS was due to the possibility of resolving some coeluted peaks in the one-dimension gas chromatography. Semiquantitative analysis of the samples verified that 59% of the area on the chromatogram of bio-oil is composed by phenols and 12% by aldehydes, mainly furfural. Using the same criterion, 77% of the organic compounds in the aqueous phase are phenols. Therefore, this preliminary assessment indicates that coconut fibers have the potential to be a cost-effective and promising alternative to obtain new products and minimize environmental impact.

High-Precision 87Sr/86Sr Analyses in Wines and Their Use as a Geological Fingerprint for Tracing Geographic Provenance
Sara Marchionni - ,
Eleonora Braschi - ,
Simone Tommasini - ,
Andrea Bollati - ,
Francesca Cifelli - ,
Nadia Mulinacci - ,
Massimo Mattei *- , and
Sandro Conticelli *
The radiogenic isotopic compositions of inorganic heavy elements such as Sr, Nd, and Pb of the food chain may constitute a reliable geographic fingerprint, their isotopic ratios being inherited by the geological substratum of the territory of production. The Sr isotope composition of geomaterials (i.e., rocks and soils) is largely variable, and it depends upon the age of the rocks and their nature (e.g., genesis, composition). In this study we developed a high-precision analytical procedure for determining Sr isotopes in wines at comparable uncertainty levels of geological data. With the aim of verifying the possibility of using Sr isotope in wine as a reliable tracer for geographic provenance, we performed Sr isotope analyses of 45 bottled wines from four different geographical localities of the Italian peninsula. Their Sr isotope composition has been compared with that of rocks from the substrata (i.e., rocks) of their vineyards. In addition wines from the same winemaker but different vintage years have been analyzed to verify the constancy with time of the 87Sr/86Sr. Sr isotope compositions have been determined by solid source thermal ionization mass spectrometry following purification of Sr in a clean laboratory. 87Sr/86Sr of the analyzed wines is correlated with the isotopic values of the geological substratum of the vineyards, showing little or no variation within the same vineyard and among different vintages. Large 87Sr/86Sr variation is observed among wines from the different geographical areas, reinforcing the link with the geological substratum of the production territory. This makes Sr isotopes a robust geochemical tool for tracing the geographic authenticity and provenance of wine.

Simultaneous Spectrophotometric Determination of Cd2+, Cu2+, and Zn2+ in Rice and Vegetal Samples with Dimethyl-spiro[isobenzofurane-1,6′-pyrorolo[2,3-d]pyrimidine]-2′,3,4,5′(1′H,3′H,7′H)tetraone Using Wavelet Transformation–Feed Forward Neural Networks
Maryam Abbasi Tarighat - ,
Mohammad Reza Mohammadizadeh - , and
Gholamreza Abdi
A multicomponent analysis method for the simultaneous spectrophotometric determination of the Cd2+, Cu2+, and Zn2+ based on complex formation with dimethyl-spiro[isobenzofurane-1,6′-pyrorolo[2,3-d]pyrimidine]-2′,3,4,5′(1′H,3′H,7′H)tetraone using wavelet transformation–feed forward neural network is proposed. The analytical data showed that metal to ligand ratios in all metal complexes was 1:1. The absorption spectra were evaluated with respect to synthetic ligand concentration and pH. It was found that, at pH 6.7, the complexation reactions were completed. Spectral data were reduced using continuous wavelet transformation (CWT) and subjected to artificial neural networks. The presence of nonlinearities was confirmed by a partial response plot. The structures of the CWT–feed forward neural networks (WT-FFNN) were simplified using the corresponding wavelet coefficients of mother wavelets. Once the optimal wavelet coefficients are selected, different ANN models can be employed for the calculation of the final calibration model. The proposed methods were successfully applied to the simultaneous determination of Cd2+, Cu2+, and Zn2+ in rice, dill, tomato, and lettuce samples.
Bioactive Constituents and Functions

Analysis of Fatty Acids and Phytosterols in Ethanol Extracts of Nelumbo nucifera Seeds and Rhizomes by GC-MS
Xu Zhao - ,
Jian Shen - ,
Kyung Ja Chang - , and
Sung Hoon Kim *
The purpose of this study was to investigate the fatty acid and phytosterol contents in ethanol extracts of lotus seeds and rhizomes. These ethanol extracts were extracted with hexane. The hexane extracts were hydrolyzed in a microwave reactor, and total fatty acids and phytosterols were analyzed. The hexane extracts were also subjected to silica gel column chromatography. Nonpolar components (triglycerides and steryl-fatty acid esters) were hydrolyzed, and then the contents were analyzed. Polar components (diglycerides, monoglycerides, fatty acids, and phytosterols) were analyzed directly. Seeds contained higher concentrations of fatty acids and phytosterols compared to rhizomes. Linoleic acid, palmitic acid, and oleic acid were the main fatty acid components in seeds and rhizomes, and most of them in seeds were in the ester form. In seeds, phytosterols existed mainly in the free form rather than in steryl-fatty acid ester form. β-Sitosterol was the most abundant phytosterol in seeds and rhizomes.

Dihydroasparagusic Acid: Antioxidant and Tyrosinase Inhibitory Activities and Improved Synthesis
Alessandro Venditti - ,
Manuela Mandrone *- ,
Anna Maria Serrilli - ,
Armandodoriano Bianco - ,
Carmelina Iannello - ,
Ferruccio Poli - , and
Fabiana Antognoni
Dihydroasparagusic acid (DHAA) is the reduced form of asparagusic acid, a sulfur-containing flavor component produced by Asparagus plants. In this work, DHAA was synthetically produced by modifying some published protocols, and the synthesized molecule was tested in several in vitro assays (DPPH, ABTS, FRAP-ferrozine, BCB, deoxyribose assays) to evaluate its radical scavenging activity. Results show that DHAA is endowed with a significant in vitro antioxidant activity, comparable to that of Trolox. DHAA was also evaluated for its inhibitory activity toward tyrosinase, an enzyme involved, among others, in melanogenesis and in browning processes of plant-derived foods. DHAA was shown to exert an inhibitory effect on tyrosinase activity, and the inhibitor kinetics, analyzed by a Lineweaver–Burk plot, exhibited a competitive mechanism. Taken together, these results suggest that DHAA may be considered as a potentially active molecule for use in various fields of application, such as pharmaceutical, cosmetics, agronomic and food.

Stable Binding of Alternative Protein-Enriched Food Matrices with Concentrated Cranberry Bioflavonoids for Functional Food Applications
Mary H. Grace - ,
Ivette Guzman - ,
Diana E. Roopchand - ,
Kristin Moskal - ,
Diana M. Cheng - ,
Natasha Pogrebnyak - ,
Ilya Raskin - ,
Amy Howell - , and
Mary Ann Lila *
Defatted soy flour (DSF), soy protein isolate (SPI), hemp protein isolate (HPI), medium-roast peanut flour (MPF), and pea protein isolate (PPI) stably bind and concentrate cranberry (CB) polyphenols, creating protein/polyphenol-enriched matrices. Proanthocyanidins (PAC) in the enriched matrices ranged from 20.75 mg/g (CB-HPI) to 10.68 mg/g (CB-SPI). Anthocyanins (ANC) ranged from 3.19 mg/g (CB-DSF) to 1.68 mg/g (CB-SPI), whereas total phenolics (TP) ranged from 37.61 mg/g (CB-HPI) to 21.29 mg/g (CB-SPI). LC-MS indicated that the enriched matrices contained all identifiable ANC, PAC, and flavonols present in CB juice. Complexation with SPI stabilized and preserved the integrity of the CB polyphenolic components for at least 15 weeks at 37 °C. PAC isolated from enriched matrices demonstrated comparable antiadhesion bioactivity to PAC isolated directly from CB juice (MIC 0.4–0.16 mg/mL), indicating their potential utility for maintenance of urinary tract health. Approximately 1.0 g of polyphenol-enriched matrix delivered the same amount of PAC available in 1 cup (300 mL) of commercial CB juice cocktail, which has been shown clinically to be the prophylactic dose for reducing recurring urinary tract infections. CB-SPI inhibited Gram-positive and Gram-negative bacterial growth. Nutritional and sensory analyses indicated that the targeted CB–matrix combinations have high potential for incorporation in functional food formulations.

Formation of 4(5)-Methylimidazole and Its Precursors, α-Dicarbonyl Compounds, in Maillard Model Systems
Hae Won Jang - ,
Yaping Jiang - ,
Matt Hengel - , and
Takayuki Shibamoto *
Glyoxal, methylglyoxal, and diacetyl formed from sucrose alone and from a d-glucose/ammonia Maillard model system were analyzed by gas chromatography. They are known as precursors of 4(5)-methylimidazole (MI). Glyoxal and methylglyoxal formed more in acidic conditions than in basic conditions, whereas diacetyl formed the most at the highest basic condition of pH 12. Glyoxal formation from sucrose ranged from 0.33 to 32.90 μg/g under four different time and temperature conditions. Amounts of glyoxal, methylglyoxal, and diacetyl formed in Maillard model systems ranged from 2.98 to 46.12 μg/mL, from 8.27 to 156.61 μg/mL, and from 14.94 to 1588.45 μg/mL, respectively. 4(5)-MI formation in the same model systems ranged from 28.56 to 1269.71 μg/mL. Addition of sodium sulfite reduced formation of these chemicals significantly. Total α-dicarbonyl compounds in 12 commercial soft drinks ranged from 5.75 to 50.72 μg/mL. 4(5)-MI was found in levels ranging from 1.76 to 28.11 ng/mL in 10 commercial soft drinks.

Peroxisome Proliferator-Activated Receptor-γ Activators Monascin and Rosiglitazone Attenuate Carboxymethyllysine-Induced Fibrosis in Hepatic Stellate Cells through Regulating the Oxidative Stress Pathway but Independent of the Receptor for Advanced Glycation End Products Signaling
Wei-Hsuan Hsu - ,
Bao-Hong Lee - ,
Ya-Wen Hsu - , and
Tzu-Ming Pan *
Advanced glycation end products (AGEs) signaling through its receptors (RAGE) results in an increase in reactive oxygen species (ROS) and is thought to contribute to hepatic fibrosis via hyperglycemia. Carboxymethyllysine (CML) is a key AGE, with highly reactive dicarbonyl metabolites. We investigated the inhibitory effect of Monascus-fermented metabolite monascin and rosiglitazone on CML-induced RAGE signaling in hepatic stellate cells (HSCs) and its resulting antihepatic fibrosis activity. We found that monascin and rosiglitazone upregulated peroxisome proliferator-activated receptor-γ (PPAR-γ) to attenuate α-smooth muscle actin (SMA) and ROS generation in CML-treated HSCs in a RAGE activation-independent pathway. Therefore, monascin may delay or inhibit the progression of liver fibrosis through the activation of PPAR-γ and might prove to be a major antifibrotic mechanism to prevent liver disease.
Chemical Aspects of Biotechnology/Molecular Biology

Two Family 11 Xylanases from Achaetomium sp. Xz-8 with High Catalytic Efficiency and Application Potentials in the Brewing Industry
Liang Zhao - ,
Kun Meng - ,
Yingguo Bai - ,
Pengjun Shi - ,
Huoqing Huang - ,
Huiying Luo - ,
Yaru Wang - ,
Peilong Yang - ,
Wei Song - , and
Bin Yao *
This study identified two family-11 xylanase genes (xynC81 and xynC83) in Achaetomium sp. Xz-8, a thermophilic strain from a desert area with substantial xylanase activity, and successfully expressed them in Pichia pastoris. Their deduced amino acid sequences showed the highest identity of ≤90% to known fungal xylanases and of ≤62% with each other. The purified recombinant xylanases showed optimal activities at pH 5.5 and 60–65 °C and exhibited stability over pH 5.0–10.0 and temperatures at 55 °C and below. XynC81 had high catalytic efficiency (6082 mL/s/mg), and XynC83 was favorable for xylooligosaccharide production. Under simulated mashing conditions, combination of XynC83 and a commercial β-glucanase improved the filtration rate by 34.76%, which is much better than that of Novozymes Ultraflo (20.71%). XynC81 and XynC83 had a synergistic effect on viscosity reduction (7.08%), which is comparable with that of Ultraflo (8.47%). Thus, XynC81 and XynC83 represent good candidates for application in the brewing industry.

Selected Wheat Seed Defense Proteins Exhibit Competitive Binding to Model Microbial Lipid Interfaces
Michael R. Sanders - ,
Luke A. Clifton - ,
Cameron Neylon - ,
Richard A. Frazier - , and
Rebecca J. Green *
Puroindolines (Pins) and purothionins (Pths) are basic, amphiphilic, cysteine-rich wheat proteins that play a role in plant defense against microbial pathogens. This study examined the co-adsorption and sequential addition of Pins (Pin-a, Pin-b, and a mutant form of Pin-b with Trp-44 to Arg-44 substitution) and β-purothionin (β-Pth) model anionic lipid layers using a combination of surface pressure measurements, external reflection FTIR spectroscopy, and neutron reflectometry. Results highlighted differences in the protein binding mechanisms and in the competitive binding and penetration of lipid layers between respective Pins and β-Pth. Pin-a formed a blanket-like layer of protein below the lipid surface that resulted in the reduction or inhibition of β-Pth penetration of the lipid layer. Wild-type Pin-b participated in co-operative binding with β-Pth, whereas the mutant Pin-b did not bind to the lipid layer in the presence of β-Pth. The results provide further insight into the role of hydrophobic and cationic amino acid residues in antimicrobial activity.

Dual Effects of Chitosan Decoration on the Liposomal Membrane Physicochemical Properties As Affected by Chitosan Concentration and Molecular Conformation
Chen Tan - ,
Jin Xue - ,
Karangwa Eric - ,
Biao Feng - ,
Xiaoming Zhang - , and
Shuqin Xia *
This study was devoted to a further understanding of the dependence of liposomal membrane properties on chitosan conformation and proved the dual effects of chitosan. The concentration dependence of chitosan conformation in aqueous solution was illustrated by surface tension and fluorescence probe techniques. Fluorescence and Raman spectra were subsequently employed to investigate the dynamic and structural changes of the liposomal membrane resulting from chitosan decoration. Results showed that the unfolded and crimped chains of chitosan flatly adsorbed onto the membrane surface via electrostatic attraction and favored liposome stability. Furthermore, the adsorption of crimped chains seemed stronger due to the embedding of their hydrophobic moieties. However, the presence of chitosan coils induced the increase in membrane fluidity, the intrachain disorder in lipid molecules, and the gauche conformation change of choline group. Dynamic light scattering and lipid oxidation measurements demonstrated that this perturbation was correlated with the permeation of coils into the lipid bilayer.
Food and Beverage Chemistry/Biochemistry

Milk Whey Protein Modification by Coffee-Specific Phenolics: Effect on Structural and Functional Properties
Mostafa Ali - ,
Thomas Homann - ,
Mahmoud Khalil - ,
Hans-Peter Kruse - , and
Harshadrai Rawel *
A suitable vehicle for integration of bioactive plant constituents is proposed. It involves modification of proteins using phenolics and applying these for protection of labile constituents. It dissects the noncovalent and covalent interactions of β-lactoglobulin with coffee-specific phenolics. Alkaline and polyphenol oxidase modulated covalent reactions were compared. Tryptic digestion combined with MALDI-TOF-MS provided tentative allocation of the modification type and site in the protein, and an in silico modeling of modified β-lactoglobulin is proposed. The modification delivers proteins with enhanced antioxidative properties. Changed structural properties and differences in solubility, surface hydrophobicity, and emulsification were observed. The polyphenol oxidase modulated reaction provides a modified β-lactoglobulin with a high antioxidative power, is thermally more stable, requires less energy to unfold, and, when emulsified with lutein esters, exhibits their higher stability against UV light. Thus, adaptation of this modification provides an innovative approach for functionalizing proteins and their uses in the food industry.

Antioxidant Activity of High Molecular Weight Chitosan and N,O-Quaternized Chitosans
Ajun Wan *- ,
Qing Xu - ,
Yan Sun - , and
Huili Li *
The objective of this study was to evaluate the in vitro antioxidant activity of high molecular weight chitosan based films. Three kinds of water-soluble quaternized chitosans with high molecular weight, namely N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (400-HTCC and 1240-HTCC), N-(2-hydroxyl) propyl-3-triethyl ammonium chitosan chloride (400-HTEC and 1240-HTEC), and O-(2-hydroxyl) propyl-3- trimethyl ammonium chitosan chloride (400-O-HTCC) were prepared from high molecular weight chitosans (400 and 1240 kDa). The in vitro antioxidant activity of a high molecular weight chitosan (1240-CS) and five quaternized chitosans was evaluated and compared as radical scavengers against 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH•), hydroxyl radical (•OH), and superoxide radical (•O2–) using established methods, and the effect of the molecular weight, the concentration, the newly generated hydroxyl group, the extra introduced positive charge of quaternary ammonium salt group, etc., on the antioxidant activity of these high molecular weight chitosans is discussed. The data obtained in vitro models exhibited good antioxidant potency and suggested the possibility that high molecular weight chitosan based films could be effectively employed as natural antioxidant materials for application in the field of food and medicine.

Effect of Pressurized Hot Water Extraction on Antioxidants from Grape Pomace before and after Enological Fermentation
José R. Vergara-Salinas - ,
Pedro Bulnes - ,
María Carolina Zúñiga - ,
Jara Pérez-Jiménez - ,
Josep Lluís Torres - ,
María Luisa Mateos-Martín - ,
Eduardo Agosin - , and
José R. Pérez-Correa *
Grape pomace was extracted with pressurized hot water at laboratory scale before and after fermentation to explore the effects of fermentation and extraction temperature (50–200 °C) and time (5 and 30 min) on total extracted antioxidant levels and activity and to determine the content and recovery efficiency of main grape polyphenols, anthocyanins, and tannins. Fermented pomace yielded more total antioxidants (TAs), antioxidant activity, and tannins, than unfermented pomace but fewer anthocyanins. Elevating the extraction temperature increased TA extraction and antioxidant activity. Maximum anthocyanin extraction yields were achieved at 100 °C and at 150 °C for tannins and tannin–anthocyanin adducts. Using higher temperatures and longer extraction times resulted in a sharp decrease of polyphenol extraction yield. Relevant proanthocyanidin amounts were extracted only at 50 and 100 °C. Finally, TA recovery and activity were not directly related to the main polyphenol content when performing pressurized hot water grape pomace extraction.

A New Method for the Preparative Isolation of Chlorogenic Acid Lactones from Coffee and Model Roasts of 5-Caffeoylquinic Acid
Nils Kaiser - ,
David Birkholz - ,
Silvia Colomban - ,
Luciano Navarini - , and
Ulrich H. Engelhardt *
Chlorogenic acid lactones (CQL) are known to contribute to the bitter taste of roasted coffee. CQL might also have beneficial biological activities. Until now, there is a lack of pure standard compounds for quantification and biological testing. Using high-speed countercurrent chromatography, milligram amounts of lactones could be isolated. The structures of 3-O-caffeoyl-γ-quinide, 4-O-caffeoyl-muco-γ-quinide, and 5-O-caffeoyl-epi-δ-quinide were confirmed by 1D and 2D NMR spectroscopy including 13C NMR data, which were previously not available from the literature. An UHPLC method was developed that enabled the separation of the lactones from roasted coffee in significantly shorter time than conventional HPLC.

Structural Features of Copigmentation of Oenin with Different Polyphenol Copigments
Natércia Teixeira - ,
Luís Cruz - ,
Natércia F. Brás - ,
Nuno Mateus - ,
Maria João Ramos - , and
Victor de Freitas *
The copigmentation binding constants (K) for the interaction of different copigments with oenin (major red wine anthocyanin) were determined. All tests were performed in a 12% ethanol citrate buffer solution (0.2 M) at pH 3.5, with an ionic strength adjusted to 0.5 M by the addition of sodium chloride. Over the past years, several copigmentation studies were made and many copigments were tested, but none of them included prodelphinidin B3 or a dimeric-type adduct like oenin-(O)-catechin, probably due to the difficulty in obtaining them. The data yielded from this study allowed concluding that (a) the presence of a pyrogallol group in the B ring of the flavan-3-ol structure slightly increases the copimentation potential and (b) within all copigments tested oenin-(O)-catechin was revealed to be the best. According to computational studies performed on epicatechin/oenin, epigallocatechin/oenin, procyanidin B3/oenin, and oenin-(O)-catechin/oenin complexes, the ΔGbinding energy of the oenin-(O)-catechin/oenin complex is the most negative compared to the other copigmentation complexes, hence being more stable and thermodynamically favored. All structural data show that oenin-(O)-catechin and epigallocatechin are closer to the pigment molecule, which is in accordance with these two copigments having the highest experimental copigmentation binding constants for oenin.

Chemometric Classification of Apple Juices According to Variety and Geographical Origin Based on Polyphenolic Profiles
Jing Guo - ,
Tianli Yue *- ,
Yahong Yuan - , and
Yutang Wang
To characterize and classify apple juices according to apple variety and geographical origin on the basis of their polyphenol composition, the polyphenolic profiles of 58 apple juice samples belonging to 5 apple varieties and from 6 regions in Shaanxi province of China were assessed. Fifty-one of the samples were from protected designation of origin (PDO) districts. Polyphenols were determined by high-performance liquid chromatography coupled to photodiode array detection (HPLC-PDA) and to a Q Exactive quadrupole-Orbitrap mass spectrometer. Chemometric techniques including principal component analysis (PCA) and stepwise linear discriminant analysis (SLDA) were carried out on polyphenolic profiles of the samples to develop discrimination models. SLDA achieved satisfactory discriminations of apple juices according to variety and geographical origin, providing respectively 98.3 and 91.2% success rate in terms of prediction ability. This result demonstrated that polyphenols could served as characteristic indices to verify the variety and geographical origin of apple juices.

Indirect Homologous Competitive Enzyme-Linked Immunosorbent Assay for the Detection of a Class of Glycosylated Dihydrochalcones
Anupama Ranganathan - ,
Grace A. Paradise - ,
Chad A. Hansen - ,
Mark R. McCoy - ,
Shirley J. Gee - ,
Ping Zhong - ,
Dan Chang - , and
Bruce D. Hammock *
Hesperetin dihydrochalcone 4′-glucoside, 1, and phloretin 4′-glucoside, 2, belong to a family of dihydrochalcone glycosides that exhibit flavorant properties. In this study was developed a competitive, indirect homologous ELISA for the detection of targets 1 and 2 in fermentation media. Immunogen and coating antigen were prepared by conjugating hapten, 4-(3-oxo-3-(2,6-dihydroxy-4-glucoside phenyl)propyl) benzoic acid, to thyroglobulin and bovine serum albumin, respectively. Antibodies raised in rabbits M6122, M6123, and M6124 and the coating antigen were screened and characterized to determine their optimum concentrations. The optimized ELISA, developed with antibody M6122, gave IC50 values of 27.8 and 21.8 ng/mL for 1 and 2, respectively. Selectivity of the assay was assessed by measuring cross-reactivity of antibody M6122 to related congeners such as aglycones and the 2′-glycosides of hesperetin dihydrochalcone, 5 and phloretin, 6. Antibody M6122 showed very low recognition of 5 and virtually no recognition of the aglycones and 6.

Comprehensive Analysis of Nonenzymatic Post-Translational β-Lactoglobulin Modifications in Processed Milk by Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry
Jasmin Meltretter - ,
Johannes Wüst - , and
Monika Pischetsrieder *
Nonenzymatic post-translational protein modifications (nePTMs) result in changes of the protein structure that may severely influence physiological and technological protein functions. In the present study, ultrahigh-performance liquid chromatography–electrospray ionization tandem mass spectrometry (UHPLC–ESI-MS/MS) was applied for the systematic identification and site-specific analysis of nePTMs of β-lactoglobulin in processed milk. For this purpose, β-lactoglobulin, which had been heated with lactose under conditions to force nePTM formation (7 d/60 °C), was screened for predicted modifications by using full scans and enhanced resolution scan experiments combined with enhanced product ion scans. Thus, the main glycation, glycoxidation, oxidation, and deamidation products of lysine, arginine, methionine, cysteine, tryptophan, and asparagine, as well as the N-terminus, were identified. Using these MS data, a very sensitive scheduled multiple reaction monitoring method suitable for the analysis of milk products was developed. Consequently, 14 different PTM structures on 25 binding sites of β-lactoglobulin were detected in different milk products.

Fuzhuanins A and B: The B-ring Fission Lactones of Flavan-3-ols from Fuzhuan Brick-Tea
Zhen-Mei Luo - ,
Hai-Xia Du - ,
Li-Xiang Li - ,
Mao-Qiang An - ,
Zheng-Zhu Zhang - ,
Xiao-Chun Wan - ,
Guan-Hu Bao - ,
Liang Zhang - , and
Tie-Jun Ling *
Fuzhuan brick-tea is a special dark tea prepared from the leaves of Camellia sinensis var. sinensis. Its production involves a fungal fermentation stage, which forms the unique flavors and functions by a series of biochemical reactions. Our phytochemical research of the material led to the isolation of two new B-ring fission lactones of flavan-3-ols, fuzhuanins A (1) and B (2). In addition, three other flavan-3-ol derivatives (3–5), three flavone C-glycosides (6–8), eight flavonoid O-glycosides (10–17), five simple phenolics (19–23), two norisoprenoid glycosides (24, 25), two sesquiterpenoids (26, 27), and theobromine (28), as well as two flavonoid anions (9 and 18), were also identified. The structures of these compounds were determined by spectroscopic methods. Compounds 4, 19, 20, 22–24, 26, and 27 were reported for the first time in Camellia spp. and tea. Furthermore, HPLC analysis method was performed to compare the chemical constituents of the before/after fungal fermentation Fuzhuan brick-teas. Compound 1 was indicated as one of the major characteristic constituents generated in the fungal fermentation process. The IC50 value of the antiproliferative activity of 2 on HeLa cells was assayed as 4.48 μM. None of the isolated compounds showed any inhibition activity against the enteric pathogenic microbes at 800 μg/mL by the hole plate diffusion method.
Food Safety and Toxicology

Determination of Arsenic Species in Rice from Thailand and Other Asian Countries Using Simple Extraction and HPLC-ICP-MS Analysis
Sumontha Nookabkaew - ,
Nuchanart Rangkadilok - ,
Chulabhorn Mahidol - ,
Gunlatida Promsuk - , and
Jutamaad Satayavivad *
Human exposure to arsenic (As) via rice consumption is of increasing concern. In the present study, the extraction and HPLC-ICP-MS analysis for As speciation in rice were investigated. A simple extraction with water and digestion with α-amylase followed by the analysis using ion-paring mode HPLC separation was developed. The method showed good extraction efficiencies (generally >80%) and column efficiencies (>90%) for rice samples. The optimization of mobile phase showed well separated peaks of As species. The limits of quantification (LOQ) of AsIII, AsV, MMA, and DMA that were calculated based on sample mass were 1.6, 2.0, 2.0, and 1.6 μg kg–1, respectively. A total of 185 rice samples (various types of rice) collected from different four regions in Thailand and some other Asian countries were analyzed. The total As and inorganic As in rice samples were in the ranges of 22.51–375.39 and 13.89–232.62 μg kg–1, respectively. The estimated weekly intake of inorganic As from rice by Thai people accounted for 13.91–29.22% of the provisional tolerable weekly intake (PTWI).
Targeted Metabolomics Applied to Agriculture and Food

Metabolite Profiling Approach Reveals the Interface of Primary and Secondary Metabolism in Colored Cauliflowers (Brassica oleracea L. ssp. botrytis)
Soo-Yun Park - ,
Sun-Hyung Lim - ,
Sun-Hwa Ha - ,
Yunsoo Yeo - ,
Woo Tae Park - ,
Do Yeon Kwon - ,
Sang Un Park *- , and
Jae Kwang Kim *
In the present study, carotenoids, anthocyanins, and phenolic acids of cauliflowers (Brassica oleracea L. ssp. botrytis) with various colored florets (white, yellow, green, and purple) were characterized to determine their phytochemical diversity. Additionally, 48 metabolites comprising amino acids, organic acids, sugars, and sugar alcohols were identified using gas chromatography–time-of-flight mass spectrometry (GC-TOFMS). Carotenoid content was considerably higher in green cauliflower; anthocyanins were detected only in purple cauliflower. Phenolic acids were higher in both green and purple cauliflower. Results of partial least-squares discriminant, Pearson correlation, and hierarchical clustering analyses showed that green cauliflower is distinct on the basis of the high levels of amino acids and clusters derived from common or closely related biochemical pathways. These results suggest that GC-TOFMS-based metabolite profiling, combined with chemometrics, is a useful tool for determining phenotypic variation and identifying metabolic networks connecting primary and secondary metabolism.

Metabolic Effect of an Exogenous Gene on Transgenic Beauveria bassiana Using Liquid Chromatography–Mass Spectrometry-Based Metabolomics
Feifei Luo - ,
Ruili Lu - ,
Hong Zhou - ,
Fenglin Hu *- ,
Guanhu Bao - ,
Bo Huang - , and
Zengzhi Li
Genetic modification of Beauveria bassiana with the scorpion neurotoxin aaIT gene can distinctly increase its insecticidal activity, whereas the effect of this exogenous gene on the metabolism of B. bassiana is unknown until now. Thus, we investigate the global metabolic profiling of mycelia and conidia of transgenic and wild-type B. bassiana by liquid chromatography–mass spectrometry (LC–MS). Principal component analysis (PCA) and orthogonal projection to latent structure discriminant analysis (OPLS-DA) reveal clear discrimination of wild-type mycelia and conidia from transgenic mycelia and conidia. The decrease of glycerophospholipids, carnitine, and fatty acids and the increase of oxylipins, glyoxylate, pyruvic acid, acetylcarnitine, fumarate, ergothioneine, and trehalose in transgenic mycelia indicate the enhanced oxidative reactions. In contrast, most metabolites related to oxidative stress are not altered significantly in conidia, which implies that there will be no significant oxidative stress reaction when the aaIT gene is quiescent in cells.
Correspondence/Rebuttal
Comment on Acetylcholinesterase Inhibitory Activity of Volatile Oil from Peltophorum Dasyrachis Kurz Ex Bakar (Yellow Batai) and Bisabolane-Type Sesquiterpenoids
Christophe Wiart *
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