【摘要】 对纳豆芽孢杆菌CICC 20643液态发酵生产γ-聚谷氨酸(γ-PGA)的工艺进行了研究。采用单因素实验和正交实验获得了生产γ-PGA的优化培养条件:蔗糖25g/L,酵母膏5g/L,谷氨酸钠40g/L,装液量70mL/250mL锥形瓶,起始pH6.5,菌种在37℃、120r/min培养24h后,于培养基中添加5%NaCl,继续培养24h,γ-PGA的产量达到18.04g/L。实验结果表明:纳豆芽孢杆菌CICC20643是一株产γ-PGA优良菌种,在发酵过程中添加NaCl的工艺能明显提高γ-PGA的产量。更多还原

【Abstract】 Production of poly-γ-glutamic acid(γ-PGA)by cultivation of Bacillus subtilis natto CICC 20643 in submerged state had been studied.The optimum cultivation conditions through single factor and orthogonal experiments were set as follows:sucrose 25g/L,yeast extract 5g/L,glutamic acid 40g/L,initial pH at 6.5,culture volume 70mL in 250mL conical flask.Under the optimum cultivation conditions,B.subtilis natto was shaking cultivated at 37℃,120r/min for 24h,then 5%NaCl was added,and subsequently cultivated for another 24h.As a result,the yield ofγ-PGA was got at 18.04g/L.The experimental result showed that B.subtilis natto CICC 20643 was a strain of high-yieldγ-PGA and addition of NaCl in the course of cultivation could increase the yield ofγ-PGA.更多还原