Chemo-Enzymatic Epoxidation Of Oleic Acid Catalyzed With Candida SP.99-125 Lipase

Vegetable oils are a mixture of glycerine esters of unsaturated fatty acid Recently, with the ever-increasing public awareness of the green chemistry and social impacts of the fossil based materials,there has been a hot pot in the research of the renewable resource.Vegetable oils are one of the popular resource for the renewable materials synthesis, Nowadays,some vegetable oils have been put into industrial production of polymeric materials and daily chemicals. The usages of polymers form vegetable oils are widely than the petrochemicals based polymers in the medical and food industry.The aim of this study is to develop a chemo-enzymatic epoxidation of oleic acid catalyzed with Candida sp.99-125, epoxystearic acid is an important intermediate of organic synthesis.Factors which influence the epoxidation of oleic acid were optimized, FTIR and NMRwere used to identificated the epoxidation products. The works of this paper are listed below.(1)Optimization of the epoxidation reaction catalyzed by Candida sp.99-125. The factors such as solvent, reaction temperature, enzyme load, hydrogen peroxide added ways and stirring rate had been investigated. Candida sp.99-125 lipase immobilized on kieselguhr shows higher activity than other kinds of lipase temperature gradient reaction system with 0-6 h at 30?,6-8 h at 35?,and after 8 h at 40?,Under this condition,the oxirane value was 4.18% after12 h reaction with 20%wt enzyme loading(2) The separation and identification of production. Crystallization was used to separate the epoxystearic acid.The pure production was white power at room temperature, and the structure of products was identified by the FTIR and NMR.(3)Epoxystearic acid methyl estersynthesis. The epoxystearic acid could be used as plasticizer after esterification. After comparing two different substrates (epoxystearic acid and methyl ester) for the reaction, it was found that the esterification of epoxystearic acid catalyzed by lipase Candida sp.99-125 are better than methyl ester epoxidation, and the conversion was 98%.