作　　者： ; ; ; ; ; ; ; ;

机构地区： 贵州大学

出　　处： 《微生物学通报》 2010年第2期256-262,共7页

摘　　要： 利用地衣芽孢杆菌作为出发菌株,以提油后的麻疯树饼粕作为培养基,采用固态发酵方式生产蛋白酶。控制培养基湿度为125%,添加10%的乳糖和5%的蛋白胨,30°C条件下发酵3d,蛋白酶产量达到最大值(7465U/g)。酶学性质研究表明,蛋白酶最适作用pH为5?6,最适催化温度为55°C,最大催化速度Vmax为0.0324μmol/(s·mg),Km值为0.0531mmol/L。有机溶剂对酶活力有明显促进作用,10%(V/V)甲醇和5%(V/V)乙醇可以使酶活力分别提高13.55%和70.9%。Mg2+可以使蛋白酶活力提高42.54%,而Hg2+却使酶彻底失活。 Solid-state fermentation was employed to produce protease by Bacillus licheniformis using deoiled Jatropha curcas seed cake as substrate. The optimal conditions of protease production were studied. Maximum protease production （7465 U/g of dry substrate, U/g） was obtained at 125% substrate moisture, a growth period of 3 days, supplementation with 10% （wt） of lactose and 5% （wt） of peptone. The results of protease analysis showed that the optimal temperature and pH were 55℃ and 5-6, respectively. The Vmax and Km of protease produced by Bacillus licheniformis were 0.0324 μmol/（s.mg） and 0.0531 mmol/L, respectively. Organic solvent can enhance protease activity. In comparison with control, the activities were increased by 13.55% and 70.9% when the protease was solved by 10% （V/V） of methanol and 5% （V/V） ofethanol, respectively. Mg^2＋ enhanced protease activity by 42.54% while Hg^2＋ damaged protease and entirely inactive its activity.

关 键 词： 麻疯树饼粕 地衣芽孢杆菌 蛋白酶 固态发酵 酶学性质

领　　域： [生物学] [轻工技术与工程] [轻工技术与工程]