National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
Bioresour Technol. 2012 Apr;109:7-12. doi: 10.1016/j.biortech.2012.01.035. Epub 2012 Jan 20.
An alkaline protease from Bacillus licheniformis, Protex 6L, was used for synthesis of sucrose monolaurate from sucrose and vinyl laurate in a tert-amyl alcohol/DMSO/water solvent mixture. Introducing sucrose as powder after mixing vinyl laurate with solvent mixture resulted in a higher reaction rate than when sucrose was added as a solution in DMSO. Response surface methodology (RSM) was applied to optimize the major reaction variables, water content, temperature and pH of the lyophilized enzyme. The optimal conditions derived from RSM (3.4% water content, 43 °C and pH of 10.1) provided a high initial reaction rate of 8.66 ± 0.3 mg/ml/h which agreed with the predicted value of 8.70 mg/ml/h. With 1.5 mg-enzyme/ml, 98.0% of the added sucrose was region-selectively converted to 1'-O-lauroylsucrose after 9h. Under the optimized conditions, Protex 6L exhibited a higher productivity for sucrose ester synthesis than Novozym 435 and three other commonly used enzymes.
地衣芽孢杆菌碱性蛋白酶 Protex 6L 用于在叔戊醇/DMSO/水溶剂混合物中合成蔗糖月桂酸单酯，由蔗糖和乙烯月桂酸酯合成。将乙烯月桂酸酯与溶剂混合物混合后再加入蔗糖作为粉末，其反应速率高于将蔗糖作为 DMSO 溶液加入时的反应速率。采用响应面法（RSM）对主要反应变量（冻干酶的含水量、温度和 pH）进行了优化。RSM 得出的最佳条件（含水量 3.4%、温度 43°C 和 pH 值为 10.1）提供了 8.66±0.3mg/ml/h 的高初始反应速率，与预测值 8.70mg/ml/h 吻合。在 1.5mg 酶/ml 条件下，经 9h 反应，添加的蔗糖中有 98.0%区域选择性转化为 1'-O-月桂酰基蔗糖。在优化条件下，Protex 6L 用于蔗糖酯合成的产率高于 Novozym 435 和其他三种常用酶。
