响应面法优化假单胞菌TS1138的产酶条件

摘要

Pseudomonas sp. TS 1138 was used as the test strain to produce L-cysteine. The culture medium components and enzyme production conditions of strain Pseudomonas sp. TS 1138 were optimized by response surface methodology. Initially,Plackett-Burman design was used to evaluate the process variables which were relevant to the enzyme production. Four statistically significant parameters including DL-ATC, com liquid, speed of revolution and liquid volume were selected and utilized in order to optimize the process. The optimized levels of these factors were defined by response surface analysis (RSA).7H2O, 3 g/L NaC1, 190 r/min, 42 ml/500 ml, 10% of inoculum size, initial pH7.5 and 29 ℃. Cell enzyme activity was 2255 U/ml under the optimum conditions, improved by 9.8% compared with 2053 U/ml under the original conditions.%以假单胞菌(Pseudomonas sp.)TS1138为供试菌株,运用响应面法对酶法合成L-半胱氨酸所用酶的生产条件进行优化.首先利用Plackett-Burman设计从影响TS1138菌株产酶的众多因素中筛选出影响较大的四个因素:DL-ATC、玉米浆、转速和装液量.在此基础上再利用二次响应面分析法进行优化,得出了最佳的实验条件.最佳产酶培养基配方为(g/L):葡萄糖30、DL-ATC·3H2O 3.0、玉米浆3.1、尿素3、MnSO4·H2O 1、K2HPO4·3H2O 3、FeSO4·7H2O 0.01、MgSO4·7H2O 0.5、NaCl 3;最佳产酶培养条件为:摇床转速190r/min、500ml摇瓶装液量42ml、接种量10%、产酶培养基初始pH7.5、培养温度29℃.在优化条件下进行产酶培养,细胞酶活力达2255U/ml,比未优化前的2053U/ml提高了9.8%.