产L-精氨酸基因工程菌发酵培养基优化

以基因工程菌Escherichia.coli LGE35 (Thr-,Met-, Kan+)为实验菌株,利用SAS软件中的Plackett- Burman设计法,对影响菌株发酵生产L-精氨酸的八个因素进行了筛选,确定了蔗糖、硫酸铵和酵母粉为影响摇瓶发酵生产L-精氨酸的主要因素.利用响应曲面分析法对这三个主要因素的最佳水平及其交互作用进行了研究,建立了二次回归方程:Y=14.397+1.177 812 X1+0.701 125 X2-1.058 062 X3-1.067 688 X1X1+0.100 5 X1X2-1.244 813 X2X2+0.469 375 X1X3+1.296 25 X2X3-1.873 437 X3X3,并最终确定了发酵培养基为:蔗糖 71 g/L,硫酸铵31 g/L,酵母粉14 g/L,硫酸镁1 g/L,磷酸氢二钾3 g/L,L-蛋氨酸150 mg/L,L-苏氨酸100 mg/L,卡那霉素50 mg/L,VB1 100 mg/L.与对照相比,在此条件下L-精氨酸产量提高了19.26;,残糖降低了33.04;.

Optimization of Fermentation Medium for L-Arginine by Recombined Strain

The objective of this paper was to screen the 8 factors which affected batch of fermentation production of L-arginine by SAS software,the genetically engineered bacteria of E.coli LGE 35(Thr-,Met-,Kan+) were used as experimental bacterial strain.The major factors which affect the flask-shaking batch fermentation production of L-arginine secreted by the genetically engineered bacteria of E.coli LGE35(Thr-,Met-,Kan+) were investigated by SAS software.The results showed that the sucrose,ammonium sulfate and yeast extract were significant factors by the Plackett-Burman design.The optimal level of these three main factors and their interaction were studied by response surface analysis.The polynomial regression model was established and final fermentation medium was: sucrose 71 g/L,ammonium sulfate 31 g/L,yeast extract 14 g/L,MgSO4·7H2O 1 g/L,K2HPO4 3 g/L,methionine 150 mg/L,threonine 100 mg/L kanamycin 50 mg/L,VB1 100 mg/L.Under these conditions,the production of L-arginine increased by 19.26 percent,residual sugar reduced by 33.04 percent compared with the control.