内生菌产β-mannanase条件优化及底物特异性研究  

Optimal Conditions for β-mannanase Production by Endophytic Bacteria and Enzymatic Substrate Specificity

作　　者：张建新[1] 张吨 王海磊[1] 韩科芳[1] 赵杰[1] 聂国兴[1] 

机构地区：[1]河南师范大学生命科学学院,河南新乡453007 [2]周口科技职业学院,河南周口466000

出　　处：《食品研究与开发》2013年第16期100-104,共5页Food Research and Development

基　　金：河南省重点科技攻关(112102110118);河南省教育厅科技攻关(2010A180014)

摘　　要：以产β-甘露聚糖酶的植物内生菌Bacillus subtilis UD-20为研究对象,通过对产酶条件优化得出最佳产酶方案为:魔芋精粉30 g/L,蛋白胨3 g/L,硝酸铵3 g/L,氯化钙3.0 mmol/L,氯化镁2.0 mmol/L,氯化钡0.2 mmol/L,2%的接种量发酵培养72 h,酶活高达213.6 U/mL,是优化前的2.4倍,通过补料发酵使酶活提高到275.1 U/mL,较补料前提高了34%。另外,静置培养也使酶活得到了很大提高。较低的Km(10.9 mg/mL)和较高Vmax(9 960.2 U/mL)显示该酶的具有较强的底物特异性,以葡甘露聚糖为底物时的酶活高达6 116.6 U/mL,是酶解槐豆胶的22.2倍,酶解瓜尔豆胶的28.2倍。Bacillus subtilis UD-20 is an endophytic bacteria for β-mannanase production. The optimum of fermentation conditions was preliminary determined as follows： konjac glucomannan 30 g/L, peptone 3 g/L, NH4NO3 3 g/L, CaC12 2.0 mmol/L, MgC12 2.0 mmol/L, BaC12 0.2 mmol/L, inoculation volume of 2 % incubation for 72 h, the/3-mannanase activity （213.6 U/mL） was got and 2.4-fold of the original, the fed-batch fermentation activity is 275.1 U/mL and increased 34 % compared with the original. In addition, The static culture activity is better than the conventional fermentation. The lower Km value （10.9 mg/mL） and higher Vmax value （9 960.2 U/mL） showed that the β-mannanase from endophytic bacteria Bacillus subtilis UD-20 have Strong substrate specificity. The β- mannanase showed the highest activity （6 116.6 U/mL） on glucomannan, which was the best substrate, 22.2-fold of locust bean gum and 28.2-fold of guar gum.

关 键 词：内生菌 Β-甘露聚糖酶 葡甘露聚糖 静置培养 酶动力学 

分 类 号：TS201.3[轻工技术与工程—食品科学]