对1株产纤溶酶毕赤酵母工程菌菌株pk53,利用单因素试验和正交试验确定该菌株的适宜廉价发酵培养基为:麸皮1.5%,豆粕粉2.0%,KH2PO40.5%,MgSO4.7H2O 0.05%;发酵条件为:接种龄14 h,接种量1%,甲醇添加量1.5%,培养基装液量30 mL(250 mL三角瓶),生长pH为5.5,诱导pH为6.0;在此条件下培养,纤溶酶酶活力达429.06 U/mL,是初始发酵条件下酶活力的8.88倍。

The fermentation medium and conditions of the strain were studied via single factor test and orthogonal design.The optimal fermentation medium was determined as follows:glucose 1.5%,soypeptone 2.0%,KH2PO4 0.5%,MgSO4·7H2O 0.05%.The best fermentation conditions were:inoculating time 14 h,inoculating amount 1%,methanol supply 1.5%,medium volume 30 mL in 250 mL flask,initial pH 5.5.Under such conditions,the activity of fibrinolytic enzyme(corresponding to the unit of urokinase activity) was 429.06 U/mL,which was 8.88 times of the initial strain.