【摘要】 以野生菌谷氨酸棒杆菌Corynebacterium glutamicumCCTCCM 2 0 10 0 5为出发菌株 ,进行紫外和甲基磺酸乙酯逐级诱变 ,获得一株絮凝剂高产菌XMU YH1111,通过条件优化实验 ,获得突变株XMU YH1111合成生物絮凝剂的最佳发酵条件 :葡萄糖为碳源 ,尿素和酵母膏为氮源 ,培养基初始 pH 4～ 8,种子最佳种龄 16h ,接种量 5 % ,发酵罐通风量 1L/ (L·min) ,搅拌转速 10 0r/min。在此发酵条件下 ,絮凝活性最高可达到 892U/mL ,比原出发菌株CCTCCM 2 0 10 0 5的絮凝活性提高 2倍以上。更多还原

【Abstract】 A mutant XMU-YH1111 with high capacity of flocculant production was obtained by ultraviolet radiation and subsequent EMS mutagenesis using Corynebacterium glutamicum CCTCC M201005 as the parent strain. Fermentation conditions of XMU-YH1111 were also optimized. Glucose was proven to be the most favorable carbon source for bioflocculant secretion with the complexed nitrogen sources of urea and yeast extract. Initial pH of the fermentation medium seemed to have little effect on bioflocculant production when it was controlled in the range of 4 to 8. The optimum inoculum size was 5%(v/v). The favorable airflow rate and agitation speed in a 3-litre fermentor were 1 L/(L·min) and 100 r/min, respectively. Under above optimized fermentation conditions, the ultimate flocculating activity of XMU-YH1111 could reach as high as 892 U/mL, which was twice as much as that of the parent strain CCTCC M201005.更多还原