【摘要】 报道了淀粉液化芽孢杆菌(Bacillusamyloliquefacien)BS5582菌株产β-葡聚糖酶和蛋白酶的液体发酵条件优化和酶学特性的研究结果。摇瓶水平下产β-葡聚糖酶的最佳培养基(g/L)为大麦粉40,玉米粉30,豆饼粉30,Na2HPO4·12H2O6,(NH4)2SO44,MgSO·47H2O1,CaCl20.8;产酶最佳起始pH7.0,装液量25mL/250mL。种子于37℃培养10h后,接种量8%,在37℃下发酵51.75h后β-葡聚糖酶酶活最高达到182.52U/mL,蛋白酶酶活达8062U/mL。β-葡聚糖酶的最佳反应pH6.5,最佳反应温度50℃。10mmol/L的Ca2+、Na+、NH4+、K+、Mg2+对β-葡聚糖酶活性有一定的激活作用;而相同浓度的Cu2+、Fe2+则表现出较强的抑制作用。更多还原

【Abstract】 The fermentation conditions for the production of β-glucanase and protease by Bacillus amyloliquefaciens were optimized and enzyme characteristic was investigated in this paper.The best composition of medium for the flask fermentation was as follows(g/L):barley powder 40,corn powder 30,bean powder 30,Na2HPO4·12H2O 6,(NH4)2SO4 4,MgSO4·7H2O 1,CaCl2 0.8.The maximum β-glucanase activity as high as 182.52U/mL could be obtained at 37℃ for 51.75 hours with initial pH of 7.0,while the protease activity reached 8062U/mL at the same time.The optimal pH and temperature of reaction for the β-glucanase were determined as 6.5 and 37℃,respectively.It was found that the β-glucanase activity could be enhanced by 10.0 mmol/L of Ca2+,Na+,NH4+,K+,Mg2+,but could be reduced by Cu2+ and Fe2+ at the same concentration ignificantly.更多还原