响应面法优化脂肪酶活性包涵体固定化条件

Optimization of Immobilization Conditions of Lipase Active Inclusion Body by Response Surface Methodology

目的优化Serratia marcescens ECU1010脂肪酶活性包涵体的固定化条件。方法利用Plackett-Burman试验设计筛选影响固定化过程的几项因素,用最陡爬坡实验逼近最大响应区域,采用Box-Behnken试验设计及Design-Expert软件对实验结果进行二次回归分析。结果戊二醛(GA)浓度,酶浓度,GA与酶用量比对固定化过程的影响较显著。通过求解回归方程得到最佳固定化条件:GA浓度0.13%(w/v),酶浓度16.5 mg/mL,GA与酶用量比11:2。结论在优化条件下,固定化酶的酶活性可达426.6 U/L,预测值与验证实验平均值基本相符。

Objective To optimize the immobilization conditions of lipase active inclusion body.Methods Firstly,the important factors influencing the process of immobilization were evaluated by initial screening method of Plackett-Burman.Then,the path of steepest ascent was undertaken to approach the optimal region of the significant factors.Finally,Box-Behnken design and response surface analysis by Design-Expert software were adopted to further investigate the mutual interactions between the variables and the optimal values.Results The concentrations of glutaraldehyde（GA）and enzyme as well as the ratio of GA to enzyme had substantial influence on lipase immobilization.The optimal immobilization conditions were as follows： GA 0.13%（w/v）,enzyme 16.5 mg/mL,ratio of GA to enzyme of 11：2.Conclusion Under the optimal conditions,the activity of immobilized lipase can be up to 426.6 U/L,which is on the whole consistent with the predictive value.