基于Desirability函数法对米根霉发酵制备富马酸的多目标优化

以富马酸产量和生产速率为目标，通过正交实验考察了种龄，接种量，葡萄糖和尿素浓度对两者的影响，进一步利用基于响应曲面方法的Desirability函数确定了葡萄糖和尿素的最佳浓度。结果表明，最佳的种龄和接种量分别为36h和15%，葡萄糖和尿素的优化浓度为132.73和0.0586g/l，此时模型预测的富马酸产量和生产速率达到71.42g/l和0.804g/(l.h)，Desirability的函数值高达0.966。该条件下在5L发酵罐水平上进行验证试验，经过88h的发酵最终生成富马酸66.5g/l，生产速率达到0.755 g/(l.h)，与未优化前相比，产量和生产速率分别提高了13.9%和15.8%，取得了理想的效果，实现了产量和生产速率的同时优化，为发酵法制备富马酸的工业化放大奠定了基础。

Muitiple target optimization on the fumaric acid production by Rhizopus oryzae based on Desirability function

Using the strain of Rhizopus oryzae ME-F12, the fermentation conditions for fumaric acid were studied for the purpose of optimizing both fumaric acid production and productivity. An orthogonal experiment was designed to investigate the influence of glucose concentration, urea concentration, seed age and inoculation size. The optimal seed age and inoculation size was determined as 36h and 6ml, respectively. A Desirability function based on response surface analysis was further applied to perform the multiple variable optimization. The best glucose and urea concentration were determined as 132.73g/l and 0.0586g/l, respectively. The predicted value for fumaric acid production, productivity and the Desirability value were 71.42g/l, 0.804g/(l.h) and 0.966, respectively. Verification experiment was carried out on a 5L fermentor. After a 88h fermentation period, 130g/l glucose was converted into 66.5g/l fumaric acid with the productivity of 0.755 g/(l.h). Comparing to the value before optimization, the production and productivity of fumaric acid were increased by 13.9% and 15.8%. Results indicated that both the production and productivity were successfully optimized simultaneously, which laid a solid foundation for the further scale-up.