产PCA基因工程菌M18G反复补料分批培养研究

吩嗪-1-羧酸(PCA)是一种广谱、高效的微生物源农药,采用反复补料分批培养工艺可提高PCA合成速率,为实现PCA的商业化生产打下了良好的基础。本试验针对高产PCA的基因工程菌M18G,首先在摇瓶培养条件下,用正交试验法研究了培养基中各主要营养因子葡萄糖、黄豆粉、甘油、95%乙醇等对PCA产量的影响,并确定了适合PCA分泌的最佳培养基(1L)为:葡萄糖6g,黄豆粉40g,甘油6mL,95%乙醇5.9mL;然后确定了反复补料分批培养时更换新鲜培养基的最佳时间为每次培养进行48h后、体积比例为90%。在此条件下,培养进行五个周期后,PCA的合成速率可达到2.27mg/h,是优化后分批培养的1.34倍,同时延长了培养周期,有利于提高设备使用率,降低生产成本。

Repeated fed-batch culture condition for PCA production by genetic engineering strain M18G

An optimization method for repeated fed-batch culture was established with the aim of improving the productivity of PCA and providing valuable data for large scale fermentation.Under the condition of shaking flask fermentation,by means of orthogonal test,the effects of nutrition factors,such as glucose,soybean powder,glycerol and 95% ethanol,on the production of phenazine-1-carboxylic acid(PCA) by a genetic engineering strain M18G.The optimized components of culture medium were 6g glucose,22g soybean powder,6mL glycerol,5.9mL 95% ethanol in 1 liter;In repeated fed-batch culture,the optimized time and volume for refreshing culture was 90% per 48 hours.Under this condition,the productivity of PCA was up to 2.27mg/h,which was 34% increasement than that of the optimized.Also this method would greatly extend the culture cycle and reduce the cost.