补料发酵枯草芽孢杆菌合成γ-聚谷氨酸的研究

An Investigation and Comparison of Batch and Fed-batch Fermentation of Bacillus subtilis forγ-PGA Production

在5L自动发酵罐中,通过分批发酵和补料分批发酵,对枯草芽孢杆菌(Bacillus subtilis HCUL-B-115)生物合成γ-聚谷氨酸(γ-PGA)进行研究,以达到高产的目的。结果表明:在分批发酵过程中,在通入空气条件下搅拌转速由150r/min提高至250r/min,发酵结束时γ-PGA产量从11.30g/L提高到30.86g/L;在补料分批发酵过程中,在通入空气条件下,搅拌转速采用250r/min,当糖质量浓度在20g/L以下时,每次补加50mL糖质量浓度200g/L的玉米糖化液则菌体大量生长,γ-PGA产量提高到52.20g/L。

In this study,Bacillus subtilis was cultivated in a 5-liter fermentor to produce byγ-PGA by two different fermentation processes： batch fermentation and fed-batch fermentation.The results showed that increasing the agitation speed from 150 to 250 r/min could bring the yield ofγ-PGA to 30.86 g/L from 11.30 g/L in batch fermentation under ventilation conditions.Ventilation conditions and agitation at 250 r/min were also used in the fed-batch fermentation,and 50 mL of 200 g/L glucose was fed at a time when glucose concentration in fermentation broth was lower than 20 g/L,increasing the yield of γ-PGA to 52.20 g/L.