Click image for caption and other photo information.

Read the magazine story to find out more.

Bioconversion Yields New Oil-Based Compounds

Bioconversion is the name for a "green" technology that's enabling researchers to convert fatty acids in vegetable oil into entirely new chemical compounds with antimicrobial, industrial or biomedical properties.

One such compound--called DOD, or 7(S),10(S)-dihydroxy-8(E)-octadecenoic acid--curbed the laboratory growth of Candida albicans, a yeast that sometimes causes thrush and other infections in humans. Another compound, called TOD for short, stopped the rice blast fungus, raising the prospect for a biological fungicide against this crop scourge, notes Tsung Min Kuo. He is a bioconversion team chemist at the Agricultural Research Service's National Center for Agricultural Utilization Research (NCAUR) in Peoria, Ill.

Both compounds, now patented and available for licensing, are recent examples of the researchers' efforts to open new, value-added markets for vegetable oils, particularly soyoil. By one estimate, 800 million of the 18 billion total pounds of soybean oil produced from 1999-2000 surpassed what could be used domestically or exported. Bioconversion, the researchers' approach to utilizing this surplus, involves harnessing certain microbes to modify long chains of carbon in the oil.

Kuo, at NCAUR's Microbial Genomics and Bioprocessing Research Unit, refers to the technology as "green" because it generates fewer waste byproducts than chemically-driven processes. Key is creating a favorable environment in which the technology's microbial workhorses--mainly yeast and bacteria--can feed on and catalyze fatty acids inside fermentation tanks.

In addition to being antimicrobial, DOD is structurally similar to surfactants, like those in soap, and has properties applicable for use in plastics and other industrial products, according to Ching Hou, an NCAUR biochemist. The scientists' bioconversion research also has given rise to three other new compounds, including THFA. This one is derived from linolenic acid in soybean oil and resembles tetrahydrofuranyl compounds that have cancer-fighting properties.

A longer article about bioconversion processing appears in this month's issue of Agricultural Research magazine.

ARS is the U.S. Department of Agriculture's main research arm.