KSEF R&D Excellence: Selective Accumulation of Fatty Acids in Plant Oils

The use of plants as chemical factories such as the selective accumulation of epoxy and hydroxy compounds proposed here promises to greatly enhance the variety and quality of products available in the future. This requires no fossil fuel for the actual biosynthesis reactions instead using sunlight, H2O and atmospheric CO2 for the hydrocarbon syntheses. They also can directly and indirectly provide domestically produced renewable fuels. The aim of this research is to expand or provide additional renewable resources derived from crop plants that are industrially valuable. Engineering oilseeds (e.g. soybeans) for high epoxy and hydroxy fatty acid accumulation in triglyceride is the long-term goal. This would greatly increase the value of such improved seeds and should reduce epoxy production costs. Soybeans are an important crop for Kentucky agriculture. A considerable market currently exists for such molecules particularly in coatings, resins and plastics. Presently most of these are derived from petroleum. Certain genotypes of several plant species, however, accumulate high levels of epoxy and hydroxy fatty acids in the seed oil. The best examples of this are Vernonia galamensis and Ricinus communis but they cannot be grown to produce seed at near the efficiency (and hence cost) of current commercial oilseeds limiting their potential as industrial sources of epoxy compounds. Epoxygenase and hydroxylase genes have been cloned from several accumulators of epoxy and hydroxy fatty acids and high expression in developing Arabidopsis or soybean embryos can result in up to ~ 10% of these compounds in the seed oil but this is insufficient for commercial production in oilseeds. The selective accumulation of specific fatty acids into triacylglyceride appears to be the key to the effective commercialization of this process. Genes encoding enzymes identified to be important in the selective accumulation of oxygenated fatty acids in triacylglycerols will be cloned and tested for their importance in this process.