白色链霉菌发酵生产ε-聚赖氨酸工艺的优化

Optimization of the Fermentation Technology of ε-polylysine by Streptomyces albus

采用白色链霉菌N31-69菌株发酵制备ε-聚赖氨酸,考察碳源、氮源等因素对ε-聚赖氨酸产量的影响,优化发酵培养基。结果表明,优化的培养基为葡萄糖、(NH4)2SO4和酵母浸出粉的浓度分别为30、7、7 g/L,ε-聚赖氨酸摇瓶发酵产量达1.519 g/L,比优化前的产量提高了28.0%。进一步对N31-69菌株在5 L发酵罐内的发酵工艺进行优化,发现发酵48 h后采用流加补糖方式控制还原糖浓度为10～15 g/L,从72 h开始控制pH为4.3,发酵168 h后ε-聚赖氨酸的产量可达15.60 g/L。

The effects of carbon source, nitrogen sources on fermentation of e-polylysine biosynthesis in shake flasks by Streptomyces albus strain N31-69 were studied. The results showed that content of glucose, （NH4）2SO4, yeast extract powder in the optimum medium was 30, 7, 7 g/L, respectively. The fermentation yield of e-polylysine could reach to 1.519 g/L, increased by 28.0% compared with the original medium. Batch fermentation of e-polylysine in 5 L bioreactor was carried out. Controlling pH at 4.3 after 72 h of fermentation and controlling glucose concentration at 10-15 g/L by fed-batch strategy, the fermentation yield of e-polylysine reached up to 15.60 g/L after 168 h of fermentation.