重组大肠杆菌摇瓶发酵产环湖精葡基转移酶条件的优化

Study on optimization of production conditions of cyclodextrin glucanotransferase by Recombinant E.coli

对一株表达环糊精葡基转移酶基因工程菌E·coliBL21(DE3)产环糊精葡基转移酶的发酵条件进行了研究。利用单因素实验和正交实验获得该菌株产环糊精葡基转移酶的最佳条件为:种子培养时间14h,接种量3%,培养温度37℃,培养基初始pH8·0,发酵培养基的组成为玉米粉1·5%、玉米浆6%、蛋白胨1·0%,500mL三角瓶装液量为50mL,210r/min振荡培养,其发酵液酶活可达5010U/mL。

Production conditions of cyclodextrin glucanotransferase （CGTase） by Recombinant E.coli were studied. The optimal fermentation conditions for cyclodextrin glucanotransferase production were determined by a singlefactional experiment and orthogonal experiment.The results showed that the optimal conditions were as follows： inoculation time and inoculation amount was 14h and 3% respectively, incubation temperature 37℃, pH 8.0.The compositions of fermentation medium were maize powder 1.5% ,corn steep liquor 6% and peptone 1.0%.The load of 500mL-flask was 50mL and the shaking incubation took 24h at 210r/min and the enzyme activity could reach to 5010U/mL.