AOT逆胶束体系脂肪酶催化合成油酸乙酯

Enzymatic Synthesis of Ethyl Oleate by Lipase in AOT Reverse Micellar System

在二-(2-乙基己基)琥珀酸酯磺酸钠和异辛烷构建的逆胶束体系中,以Lipex脂肪酶为催化剂,合成了油酸乙酯,考察了各影响因素对其产率的影响,并进行了脂肪酶紫外荧光检测和体系粒度分析.结果表明,Lipex脂肪酶具有良好的催化活性,反应条件优化选用异辛烷为溶剂,在反应温度25℃、缓冲液pH6.5、水/表面活性剂(摩尔比)10、乙醇/油酸(摩尔比)20及Lipex脂肪酶浓度0.035g/L、油酸浓度0.005mol/L、摇床转速150r/min、反应36h的条件下,油酸乙酯产率达到71.25%.逆胶束粒度和酶构象直接影响酶活性,最适逆胶束粒度约为80nm.

Synthesis of ethyl oleate catalyzed by Lipex lipase in AOT/isooctane reverse micellar system was studied. The influential factors on its yield were investigated. The fluorescence analysis of Lipex lipase and particle size analysis of reverse micellar system were carried out. It was confirmed that Lipex lipase had a good activation in the AOT reverse micellar system, and the best solvent was isooctane. The reaction conditions were optimized. When the temperature was 25 ℃, buffer pH 6.5, molar ratio of water to surfactant 10, molar ratio of alcohol to oleic acid 20, concentration of oleic acid and Lipex lipase 0.005 mol/L and 0.035 g/L respectively, agitation speed 150 r/min, and reaction time 36 h, the yield of ethyl oleate reached 71.25%. The activity of Lipex lipase was affected by the particle size of reverse micellar system and configuration of Lipex lipase. The suitable particle size of reverse micella was about 80 nm.