脂肪酶催化合成α-生育酚阿魏酸酯

摘要

通过比较6种脂肪酶作为催化剂、4种有机溶剂和无溶剂底物作为反应介质对a-生育酚阿魏酸酯合成的影响,发现在以固定化南极假丝酵母脂肪酶B(Novozym435)作为催化剂,甲苯作为反应介质的有机溶剂体系中产率达17.7%,在无溶剂体系中产率达23.8%.和甲苯相比无溶剂体系是更理想的反应体系.通过实验确定无溶剂体系中的最佳反应条件:α-生育酚和阿魏酸乙酯的物质的量比为5:1、水活度<0.01、加酶量与底物质量比为5%、温度为60℃、转速为180 r/min,反应72 h时最高产率可达25.47%.向介质中添加4%的极性硅胶,反应72 h后产率达到29.2%.%By using six kinds of lipases as biocatalyst, four kinds of organic solvents and Solvent - Free system as reaction medium, Lipase - catalyzed synthesis of α - Tocopheryl ferulate was studied.The results indicated that the yield of α- Tocopheryl ferulate was 17.7％ in using the immobilized lipase B from Candida Antarctica (Novozym 435) as the biocatalyst and the toluene as the reaction medium,but it was 23.8％ in the Solvent -Free medium.So the solvent - free medium is a more desirable reaction system.When the molar ratio of alpha - tocopheryl to ethyl ferulate (EF) was 5:1 ,water activity was ＜0.01 ,the ratio of enzyme to substrate was 5％ (W/W) ,the temperature and stirring rate were 60 ℃ and 180 r/min,the maximum yield of 25.47％ was reached after 72 -hour incubation; using 4％ polarity silica gel/substrate (W/W)in solvent- free medium,the yield of 29.2％ was reached after 72 h.