【摘要】 对纤溶酶产生菌B .L .PY进行了紫外线与亚硝基胍复合诱变 ,选育到突变株B .L .PYUM ,其纤溶酶产量较出发菌株提高了 2 7.2 % .通过正交分析法进一步优化了该突变株的发酵条件为 (% ) :食用蔗糖 3,玉米粉 1.1,酵母膏 0 .2 ,MgSO4 ·7H2 O 0 .0 9,CaCl2 0 .0 2 ,K2 HPO4 0 .1,pH7.2 ,通气量为 1∶0 .5～ 1∶1,转速为 4 50r/min ,37℃下发酵 4d ,其纤溶酶产量为 1140U/mL ,较出发菌株提高 4 0 .7% .更多还原

【Abstract】 A fibrinolytic enzyme producing strain B.L.PY was treated with both ultraviolet rays and MNNG (N methyl N’ nitro N nitrosoguanidine),and a mutant strain B.L.PYUM with high yield of plasmin and stability was obtained,whose enzyme activity increased by 27.2 % over strain B.L.PY. Fermentation conditions for enzyme production have been established:Composititon of the medium (%) is edible sucrose 3,corn flour 1.1,yeast extract 0.2,,MgSO 4·7H 2O 0.09, CaCl 2 0.02,K 2HPO 4 0.1,pH7.2. After fermentation in 1.5 liter of fermentor at 37℃ with an aeration rate of 1∶0.5～1∶1 for 4 days,the average fibrinolytic activity was about 1140U/mL culture broth,increased by 40.7 % over the mutant.更多还原