玉米秸秆酶解液发酵生产丙酸联产益生菌

Production of propionic acid and probiotics using corn stalk hydrolysate

分别以葡萄糖和玉米秸秆酶解液作为碳源,研究了利用玉米秸秆酶解液发酵生产丙酸的可行性。考察了秸秆酶解液糖浓度对丙酸发酵的影响,建立了丙酸和益生菌联产的补料分批发酵工艺,有效解决了高糖秸秆酶解液对丙酸发酵的抑制问题,提高了丙酸产量和菌体量。补料分批工艺：初始糖浓度为15 g/L,通过间歇补料维持葡萄糖浓度在15 g/L以下,用氨水调节pH为6.8-7.0,发酵周期130 h,丙酸产量可达19.97 g/L,丙酸产生速率为0.15 g/L.h,活菌数达到6.90×10^12 cfu/mL。

The feasibility of propionic acid fermentation using corn stalk hydrolysate had been studied by corn stalk hydrolysate and glucose as the carbon source for Propionibacterium freudenreichii fermentation,respectively.In this article,the effect of corn stalk hydrolysate concentration on the propionic acid fermentation was studied.Based on the changes of related parameters in corn stalk hydrolysate fermentation process,the fed-batch fermentation process was established.It effectively solved the inhibition problem of high concentration of corn stalk hydrolysate on the propionic acid fermentation,improved the yield of propionic acid and biomass.The fed-batch fermentation process：the initial glucose concentration was 15 g/L,feeding the high concentration corn stalk hydrolysate medium to keep the glucose concentration below 15 g/L,regulating pH 6.8 ~ 7.0 by ammonia water.After fed-batch fermentation of 130 h,the production of propionic acid was 19.97 g/L and the productivity was 0.15 g/L·h.The viable number of Propionibacterium freudenreichii was up to 6.90×1012cfu/mL.