生物素对L-缬氨酸发酵的影响

Effect of Biotin Addition on Microbial Production of L-Valine

为研究生物素添加量对谷氨酸棒状杆菌(Corynebacterium glutamate)发酵生产L-缬氨酸的影响,以谷氨酸棒状杆菌XV0505(Leu^-+Ile^-+2-TA^r+α-AB^r+SG^r)为供试菌株,考察不同生物素添加量条件下菌体量、耗糖、产酸以及副产物L-丙氨酸的情况,确定了生物素最适添加量为50μg/L;利用膜偶联透析发酵方式有效解除了发酵生产过程中产生的反馈抑制现象,降低了副产物的产量,提高了L-缬氨酸的转化率及产量。与原单批次发酵的工艺相比,新工艺的最终L-缬氨酸总量达到106.1 g/L,产量提高了47.4%,糖酸转化率提高到34.5%。

This work was undertaken in order to study the effect of biotin addition on L-valine production by Corynebacterium glutamate XV0505(Leu^-+Ile^-+2-TA^r+α-AB^r+SG^r).The amount of biomass,sugar consumption,acid production and the production of L-alanine as a by-product were investigated at different concentrations of biotin.As a result,the optimum amount of biotin addition was determined to be 50μg/L.Fermentation coupled with membrane dialysis effectively relieved feedback inhibition while reducing the production of the by-product and improving the conversion rate and yield of L-valine.The L-valine production by the new process was 106.1 g/L,which was increased by 47.4%compared with single batch fermentation,and the conversion rate of sugar and acid was increased to 34.5%.