【摘要】 通过苏云金芽胞杆菌工程菌BMB005发酵不同阶段补加葡萄糖发酵试验,研究了补糖对苏云金芽胞杆菌发酵的影响.结果表明:对数生长期补加葡萄糖可以提高生物量,进而使发酵液中杀虫晶体蛋白的质量分数提高33 1%,而稳定期补加葡萄糖则是通过提高菌体合成晶体蛋白的能力而使发酵液中晶体蛋白的质量分数提高18 1%. 30 L发酵罐补糖实验结果表明:在起始碳源质量浓度为3 0 g/dL的情况下,对数生长期补加1 0 g/dL葡萄糖可以将发酵液中杀虫晶体蛋白的质量分数和生物效价分别提高37%和51%;稳定期补加 1 0 g/dL葡萄糖可以将发酵液中杀虫晶体蛋白的质量分数和生物效价分别提高33 7%和75 1%;而且稳定期补加比对数生长期补加葡萄糖更有利于增效因子的合成.更多还原

【Abstract】 The effect of glucose feed on the fermentation of Bacillus thuringiensis BMB005 were investigated by feeding glucose at the exponential and stationary growth phases, respectively. In flasks, better effects were obtained by feeding glucose at the exponential phase causing a higher biomass concentration and the concentration of ICPs could be enhanced by 33.1%. When feeding glucose at stationary phase which increased the synthesis capability and the concentration of ICPs could be enhanced by 18.1% in turn. Implementing the fermentation in a 30 L B.Braun fermentor by constant feeding 1.0 g/dL glucose at exponential phase, the concentration of ICPs and the titer could be enhanced by 37% and 51%, respectively. while the concentration of ICPs and titer increased 33.7% and 75.1%, respectively, when feeding 1.0 g/dL glucose at the stationary phase. It is concluded that, the synthesis of synergistic factor can be promoted more effectively when feeding glucose at the stationary phase rather than exponential phase.更多还原