[Objective] To enhance amylase,protease and cellulase activities of Bacillus licheniformis LCB-8 by ultraviolet mutagenesis. [Method ] Ultraviolet light was used to mutate this strain. The activities of amylase, protease and cellulase were determined to get high - yielding strains. [Result] The best time for ultraviolet mutation was 30 s,and the mortality rate reached 72.4%. After primary screening and rescreening,two better strains were obtained. After mutagenesis,the activities of amylase,protease and cellulase of DY-97 strain were enhanced by 150% ,78% and 17% respectively. After mutagenesis,the activities of cellulase,amylase and protease of DY-34 strain were enhanced by 31% ,46% and 64% respectively . [ Conclusion ] The DY-97 strain is suitable for fermentation of feed rich in protein and amylum, whereas the DY-34 strain is suitable for fermentation of feed rich in cellulose.%[目的]对地表芽孢杆菌LCB-8进行紫外诱变,以提高其产淀粉酶、蛋白酶和纤维素酶的能力.[方法]利用紫外线进行诱变,并对诱变株淀粉酶、蛋白酶和纤维素酶的活力进行定性和定量测定.[结果]当紫外诱变的时间为30 s时,菌落的致死率达72.4％,因此紫外线照射诱变最佳时间为30s.经初筛和复筛,得到2株较好的诱变株.其中,DY-97的淀粉酶活提高150％,蛋白酶活提高78％,纤维素酶活提高17％；DY-34的纤维素酶活提高31％,淀粉酶活提高46％,蛋白酶活提高64％.[结论]通过诱变筛选得到的DY-97可用于含蛋白质和淀粉较多的饲料发酵,而DY-34可用于含纤维素较多的饲料发酵.
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