摘要
本试验以实验室克隆表达的产琼脂硫酸酯酶的重组大肠杆菌(E.coli-ars)为研究对象,首先在摇瓶中对其诱导条件进行单因素优化,得到最佳条件为:诱导温度21℃,诱导时间24h,诱导剂α-乳糖4g/L,诱导初始菌浓度(OD_(50))0.6;然后在5 L罐中对菌株进行发酵,在发酵过程中进行补料试验,结果表明补料提高了生物量,但是对酶活力没有促进效果。最后在摇瓶及5 L罐发酵基础上,分别进行20 L和200 L发酵罐的中试放大实验,结果表明,20 L罐中最大酶活力为157.5 U/mL,200 L罐中的最大酶活力为110.4 U/mL。
This experiment regarded the strain of recombinant Escherichia coli(E.coli-ars) which produced recombinant agar sulfatase as the research object.First,the optimization of induction conditions in shaking flask were implemented by single factor experiment to enhance enzyme production,and then the optimal induction conditions were obtained:induction temperature 21℃,induction time 24 h,inducing agent α-lactose 4g/L,inducing initial biomass(OD_(600)) 0.6.Thereafter,the fermented experiment of E.coli-ars in 5 L bioreactor was carried out.Research results indicated that additional medium significantly improved cell density,while it had no effect on enzyme accumulation.Finally,the pilot scale test of 20 L and 200 L were conducted on the basis of the optimized fermentation processes of shaking flask and 5 L bioreactor.The enzyme activity of the agar sulfatase in 20 L and 200 L bioreactor reached 157.5 U/mL and 110.4 U/mL,respectively.
引文