Enzymatic Epoxidation of High Oleic Soybean Oil

We report the production of epoxidized high oleic soybean oil using immobilized lipase as a sustainable replacement for the current acid-catalyzed process. Enzymatic epoxidation of conventional oil at 35 °C both with and without toluene resulted in yields of nearly 100%. While the addition of free fatty acids (FFA) to the reaction did not prevent hydrolysis of triglycerides, the yields were significantly higher when oleic acid (OA) was added at 8.0% of the oil mass. Relative reaction rates of unsaturated fatty acids for oleic and linoleic acid are similar and half that of linolenic acid, although full epoxidation of linolenic acid was not observed. Oil from high oleic genetically modified soybeans resulted in epoxidation yields of 95% at 35 °C without FFA added. These results suggest that toluene and FFA are not necessary to achieve high yields with enzymatic epoxidation at 35 °C, especially for high OA soybean oil.