谷氨酸发酵溶氧研究(Ⅰ)

Study on the Dissolved Oxygen in Fermentation of Glutamic Acid

采用带溶氧电极的摇瓶对谷氨酸发酵过程进行研究,结果表明,只有对发酵过程(特别是生产期)的溶氧严加控制,才有可能得到谷氨酸高产。在装液量为30ml,摇床转速为160-180r/min,发酵中期溶氧水平8-10％时,谷氨酸产率6.56％,糖酸转化率55％。当采用pH和溶氧为标准补尿时,所得pH曲线及溶氧曲线不完全一致,但产酸率很接近,说明溶氧曲线至少可以作为补尿及判断发酵终点的依据之一。

The fermentation of glutamic acid (GA) was investigated by adopting shaking flask with dissolved oxygen (DO) electrode. The results reveal that a high yield of GA can be obtained only if the dissolved oxygen in fermentation especially during the production phase is strictly controlled. With a medium of 30 ml and a shaker with rotating speed of 160- 180 r/min and a DO level of 8-10% during the metaphase of fermentation, a GA yield of 6. 56% and a sugar acid conversion rate of 55% can be achieved. When pH and DO are taken as the criteria of urea addition, the curves of pH and DO are not fully conform with but GA yield and sugar acid conversion rate are close to one another. It shows that DO curve may serve at least as the basis for urea addition and for assessing the end point of fermentation.