产纤溶活性酶凝结芽孢杆菌的分离鉴定及其酶活性质初探

从传统发酵食品豆豉中分离到一株纤溶活性酶产生菌株,命名为YC 4,经鉴定为凝结芽孢杆菌(Bacilluscoagulans).纯化菌株接种到发酵培养液中,37℃ 200 rpm振荡发酵72 h,发酵上清酶活达452 IU/mL.酶活性质的初步研究结果表明,该酶对温度相对稳定,37℃保温5 h,酶活性保持80%以上;酶的适宜pH为7～9,最适pH为9;用改良的纤维蛋白平板测定其酶活作用方式表明,该酶既有直接纤溶活性,也有纤溶酶原激活活性.

Abstract：

A fibrinolytic enzyme-producing strain, YC-4, was screened and purified from douchi - a Chinese traditional fermented food, and was identified as Bacillus coagulans. After the strain was cultured in BPY medium at 37 ℃ and 200 rpm for 72 h, the fibrinolytic activity of its supernatant was up to 452 IU/mL.The fibrinolytic enzyme from the supernatant was stable below 37 ℃ and its preferable pH ranged from 7 to 9, with 9 being the optimum. Further research with plate determination indicated that the fibrinolytic enzyme showed not only direct fibrinolytic activity, but also plasminogen activator activity.