MOVING FROM agricultural chemistry to chemistry from agriculture, professor Kris Arvid Berglund of the department of chemical engineering and materials science at Michigan State University discussed the direct production of chemical feedstocks from biomass. (Berglund will soon join the faculty of Luleä University of Technology, in Sweden.) Biomass provides an opportunity to bypass petroleum but still use the concept of generating family trees of compounds by starting from a few simple platform molecules such as methane, ethanol, and lactic acid, Berglund said.

In Orlando, Berglund primarily discussed the use of succinic acid as a feedstock that can be used to prepare value-added chemicals and polymers. The patented technology to generate succinic acid involves a two-step fermentation of sugars derived from plants--such as corn, sugar beets, or wood--by a strain of Escherichia coli. The process, which has been validated on a 150,000-L scale, generates a succinate ion that is isolated as ammonium succinate. Succinic acid can be precipitated from solution by the addition of ammonium bisulfate.

Succinate salts, succinate esters, and succinic acid can be converted to a host of useful industrial and consumer products, Berglund said. Succinate salts are becoming popular as noncorrosive, low-toxicity runway deicing chemicals used in conjunction with glycols, he noted. Diethyl succinate is being used as a low-volatile, low-toxicity replacement for chlorinated solvents for cleaning metal parts.

Succinic acid is used in food and beverages as an acidulant, similar to citric acid, and can be used as a monomer for polyesters, he added. Berglund and coworkers' research has been completed over a number of years with funding and technology development from the Department of Energy.

Being able to learn from nature while doing agricultural chemistry and to utilize natural resources such as enzymes and technologies such as photosynthesis, Nelson said, "amply illustrates why agricultural applications of green chemistry are a central component both to the practice of green chemistry and to the future development of agriculture."

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