以高浓度葡萄糖为碳源的L-苏氨酸发酵工艺研究

Study on L-threonine fermentation under high glucose concentration

以L-苏氨酸生产菌TRFC为供试菌株,研究了高葡萄糖浓度下各种生长因子和培养条件对L-苏氨酸发酵的影响。结果表明,脯氨酸可以解除高浓度葡萄糖对L-苏氨酸发酵的抑制作用,生物素可以提高L-苏氨酸生产菌的细胞得率及L-苏氨酸的产量,利用摇瓶发酵确定最佳用量分别为60mg/L和120μg/L;控制pH7.0和采用控制溶氧的脉冲补料方式L-苏氨酸产量得到进一步的提高。在最优条件下,利用10L发酵罐发酵38h,L-苏氨酸产量可达110.2g/L,糖酸转化率为45.7%。

Taking L-threonine Producing Strain TRFC as bacterial strains,the effect of the growth factors and culture conditions on the L-threonine fermentation under high glucose concentration was studied.The proline could release from restrain of high glucose concentration to L-threonine fermentation,the biotin could improve the cell yield and L-threonine yield,the optimal dosage were 60mg/L and 120μg/L respectively in shaking flask fermentation;The L-threonine yield could improve when pH was 7.0 and adopted pulse feed mode of controlling dissolved oxygen.Under optimal conditions,fermented 38h in 10L fermentor,the L-threonine yield could reach 110.2g/L,glucose acid invert ratio was 45.7%.