L-Gln高产突变菌株发酵条件的初步优化

将诱变实验筛选出的遗传稳定性高产突变株C.glutamicum N-U-6作为研究对象,采用单次单因子非统计优化技术确定了它在培养温度为30℃下250 mL的摇瓶培养条件为:150 g.L-1葡萄糖,最佳无机氮源及其浓度为:40 g.L-1NH4Cl;最佳有机氮源及其浓度:14 g.L-1尿素;玉米浆浓度:10 g.L-1,初始pH为7.2,装液量为30 mL,种龄为12 h,接种量为10%。谷氨酰胺产量达到37.21 g.L-1,比优化前的突变株(33.54 g.L-1)提高10.9%。

Optimization of the Fermentation Process of A Highly L-Glutamine-Producting Mutant

A mutant（C.glutamicum N-U-6） with higher L-glutamine production has been obtaind,and its fermentation conditions were optimized.The effect of various factors on glutamine fermentation by using one-factor-at-a-time method was investigated.It was found that the optimal carbon source was glucose（150 g·L-1）,inorganic nitrogen source was NH4Cl（40 g·L-1）,and organic nitrogen was urea（14 g·L-1） ＋corn steep liquor（1 g/L）.The optimum fermentation conditions in Erlenmeyer flask of 250 mL were initial pH of 7.2,the inoculum concentration of 10 %,and the inoculum age of 12 h,and the liquid volume of 30 mL.C.glutamicum N-U-6 produced 10.9% more glutamine（37.21 g·L-1） under this optimized conditions than that under unoptimized conditions（33.54 g·L-1）.