大孔树脂修饰固定化脂肪酶催化合成L-薄荷醇酯  

Synthesis of L-Menthol Oleate Catalyzed by Lipase Immobilized on Modified Macroporous Resins

作　　者：李雪玉 周海燕[1] 周华[1] 韦萍[1] LI Xue-yu;ZHOU Hai-yan;ZHOU Hua;WEI Ping(College of Biological and Pharmaceutical Engineering,Nanjing Tech University,Nanjing 211800,China)

机构地区：[1]南京工业大学生物与制药工程学院,江苏南京211800

出　　处：《高校化学工程学报》2018年第5期1134-1139,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：国家重点基础研究计划(973)(2013CB733904)

摘　　要：L-薄荷醇酯是薄荷醇与脂肪酸作用形成的酯类化合物,具有强烈的清凉作用和清新的甜刺激气味,在化妆品、医药、食品以及化工领域有重要的应用,酶法是其首选的合成方法。研究以大孔树脂固定化脂肪酶为催化剂,在无溶剂体系中,对酶促合成L-薄荷醇酯的反应条件进行了优化。在底物摩尔比为1:1,L-薄荷醇浓度为1 mol?L-1,添加1.0U的固定化脂肪酶和4μL微量水的条件下,50℃,180 r?min-1反应24 h,油酸薄荷醇酯酯化率分别达91%(NKA)和89.8%(HA)。在优化条件下,分别以经多巴胺修饰的大孔树脂NKA固定化脂肪酶和以对苯醌修饰活化的大孔树脂HA固定化脂肪酶为催化剂合成油酸薄荷醇酯,酶的共价固定化均有利于维持酶的构象和提高催化反应的速率,酯化率分别可达94.6%、95.8%。连续催化反应10次后,共价固定化酶的稳定性比吸附固定化酶提高了1.75倍,表明多巴胺和聚乙二醇对载体的修饰均能明显提升固定化脂肪酶的催化性能。L-menthol oleate is usually synthesized with menthol and fatty acid, and it is an efficient mint with fresh odor, which has important applications in cosmetics, medicine and food industry. Enzymatic methods are usually the optimal synthetic method. The esterification of L-menthol oleate was studied in solvent-free system using lipase immobilized on macroporous resin as the catalyst, and the optimal reaction conditions for enzymatic synthesis of L-menthol oleate were studied. The best esterification rates were 91%（NKA） and 89.8%（HA） under conditions of 1 mol·L^-1 L-menthol, molar ratio of acid to alcohol = 1, enzyme activity = 1 U, temperature = 50℃ and water = 4 μL with reaction time = 24 h. The immobilized lipase with resins modified with dopamine or benzoquinone show esterification rates of 94.6% and 95.8%, respectively. Covalent immobilization is beneficial for lipase stability and esterification, and the esterification rates of the covalent immobilized lipase are over 70% after ten batches, which is 1.75 times higher than that of the adsorbed immobilized lipase. These results show that the modification of resins with dopamine and polyethylene glycol can improve the catalytic performance of immobilized lipase.

关 键 词：脂肪酶 多巴胺 聚乙二醇 大孔树脂 油酸薄荷醇酯 

分 类 号：Q-814.9[生物学]