用于丁酸香叶酯合成的褶皱假丝酵母脂肪酶固定化

Immobilization of Candida rugosa lipase for the Synthesis of Geranyl Butyrate

对褶皱假丝酵母脂肪酶(Candida rugosa lipase,CRL)固定化进行研究,采用吸附法将CRL固定在4种不同树脂上,采用考马斯亮蓝法测定酶蛋白在树脂上的固定化率,GC测定催化合成丁酸香叶酯的酯化率,筛选出固定化效果最好的弱酸性大孔阳离子交换树脂D151。采用单因素实验考察酶液浓度、磷酸盐缓冲液pH值以及固定化温度对固定化效果的影响,以固定化酶催化合成丁酸香叶酯的酯化率为指标,优化固定化过程。结果表明,CRL经树脂D151固定后,在酶液质量浓度15 mg/mL,磷酸盐缓冲液pH 6.5,固定化温度45℃条件下,吸附8 h,固定化酶具有最高的催化性能,丁酸香叶酯的酯化率可达84%。

This study focused on the immobilization of Candida rugosa lipase(CRL)onto four kinds of different resins by adsorption.The Bradford method was adopted to determine the immobilization ratio,and GC method was used to measure esterification ratio of geranyl butyrate.Finally,the weak-acidic macroporous cation exchange resin D151 obtained the best results of immobilization.Taking the influence of factors including enzyme concentration,the pH of phosphate buffer and the temperature into consideration,the esterification ratio of geranyl butyrate production catalyzed by the immobilized CRL was set as evaluation index to optimize the immobilization process.The results indicated that the highest esterification ratio of 84%could be achieved by the CRL immobilized on D151 resin under optimized conditions:15 mg/mLCRL,pH of the phosphate buffer 6.5,and immobilization temperature 45℃。