高产脂肪酶菌株的筛选鉴定及产酶条件优化

Screening and identification of high yield lipase strains and optimization of enzyme production conditions

采用罗丹明B平板法和脂肪酶活力测定从张弓老酒大曲中分离筛选出一株高产脂肪酶菌株E-11,经形态学、生理生化试验和16SrDNA序列分析,鉴定该菌株为枯草芽孢杆菌(Bacillus subtilis)。通过单因素和响应面试验设计对该菌株的产酶条件进行优化,结果表明,最佳产酶条件为葡萄糖3%、蛋白胨4%、初始pH值为8.0。优化后的脂肪酶活力达15.09U/mL,是优化前产酶能力的1.2倍。

A high yield lipase strain E-11 was isolated and screened from Daqu of Zhanggonglaojiu by rhodamine B plate method and lipase activity determination. After morphological,physiological and biochemical tests and 16S rDNA sequences analysis,the strain was identified as Bacillus subtilis. The optimum conditions of enzyme production were optimized by single factor tests and response surface methodology and were determined as follows: glucose 3%,peptone 4%,and initial pH 8.0. Under the optimal conditions,the lipase activity reached 15.09 U/ml,which was 1.2 times that of before optimization.