地衣芽胞杆菌WX-02补糖发酵聚γ-谷氨酸的工艺优化

以地衣芽胞杆菌(Bacillus licheniformis)WX-02为研究对象,在摇瓶发酵中得到优化的葡萄糖补料方案,即初始葡萄糖质量浓度为70g/L时,发酵至15h一次性补加15g/L葡萄糖。将此补料方案在3L发酵罐上进行验证,结果表明:发酵生物量和聚γ-谷氨酸产量最大值分别为3.9g/L和44.5g/L,与对照相比分别提高56%和50%;谷氨酸利用率达到46%,而对照中仅为30%。通过补糖可以提高生物量,提高对谷氨酸的利用率,从而提高聚γ-谷氨酸发酵水平。

Optimization of glucose fed-batch culture in poly(γ-glutamic acid) fermentation by Bacillus licheniformis WX-02

Through flask-shaking fed-batch fermentation,the optimum system of glucose feeding for poly(γ-glutamic acid)(γ-PGA) fermentation by Bacillus licheniformis WX-02 was summerized as follows:the initial concentration of glucose was 70.0 g/L,then 15.0 g/L of glucose was added at 15th hour of fermentation carried out in a 3.0 L fermentor.The results showed that the biomass and the yield of γ-PGA were 3.9 g/L and 44.5 g/L,increasing 56% and 50% compared with the control.The utilization rate of glutamic acid in the end of fermentation was 46%,while that of control was 30%.Feeding glucose at the 15th hour of fermentation process could increase biomass,enhance utilization of glutamic acid and finally increase the γ-PGA yield by B.licheniformis WX-02.