共固定化酶对反胶束体系油酸酯化的催化条件优化  

Optimization conditions of co-immobilized double enzymes catalytic esterification of oleic acid in reverse micellar system

作　　者：包姗 袁兴中[1,2] 彭馨[1,2] 刘欢[1,2] 马玉洁[1,2] 曾光明[1,2] 

机构地区：[1]湖南大学环境科学与工程学院,长沙410082 [2]湖南大学环境生物与控制教育部重点实验室,长沙410082

出　　处：《环境工程学报》2016年第4期2016-2022,共7页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(50978087)

摘　　要：采用吸附共固定化纤维素酶和脂肪酶的双酶体系,同时采用生物表面活性剂鼠李糖脂(rhamnolipid,RL)构建RL/异辛烷/正己醇反胶束体系.考察共固定化双酶在RL/异辛烷/正己醇反胶束体系中对油酸酯化催化的优化条件和共固定化双酶的稳定性。结果表明,以生物炭作为载体的催化效果优于活性炭和明胶。在p H=6,临界胶束浓度(CMC)为60,反应2 h,温度45℃时共固定化双酶在反胶束体系对油酸的酯化效果最好,动力学米氏常数K_m=26.6,v_(max)=50 mmol/(L·min·mg)。共固定化酶在反胶束体系中重复利用的稳定性优于固定化单酶,重复使用8次后,酶活力仍保持60%以上,研究证明,共固定化双酶具有优越的可重复利用性和广阔的应用前景。In this study,cellulose and lipase were co-immobilized as the dual enzyme system by the absorption method; the RL / isooctane / n-hexanol reverse micelle system was constructed using rhamnolipids. We investigated the stability of the co-immobilized dual enzyme system and the esterification of oleic acid in the RL /isooctane / n-hexanol reverse micelle system. In addition,the reaction conditions of the esterification of oleic acid were optimized with the catalyst of co-immobilized dual enzyme system. The results indicated that biochar,the carrier of the co-immobilized dual enzymes,exhibited higher catalytic efficiency than did the activated carbon or gelatin. The co-immobilized dual enzymes had highest catalytic efficiency at p H 6. 0,RL of 60 critical micelle concentration（ CMC）,reaction time of 2 h,and reaction temperature of 45 ℃. Under these conditions,K_m and v_（max） were 26. 6 and 50 mmol /（ L·min·mg）,respectively. The stability of the reused co-immobilized dual enzyme-reverse micelle system was better than that of single enzyme immobilization,and the co-immobilized dual enzymes displayed 60% activity even after eight times of usage. These results show that the co-immobilized dual enzymes had excellent reusability and thus have great potential in the extraction industry.

关 键 词：鼠李糖脂 反胶束 共固定化双酶 酯 化 

分 类 号：X705[环境科学与工程—环境工程]