解淀粉芽孢杆菌诱变菌株NCU116-1的生物学特性及其酶系分析

Biological characteristics and exoenzymes analysis of a mutated strain Bacillus amyloliquefaciens NCU116-1

以解淀粉芽孢杆菌诱变菌株NCU116-1为出发菌,对其生物学特性和培养特征进行研究。并用国标法、羧甲基纤维素糖化法等对该突变株的主要酶系的发酵时间和酶学性质进行分析测定。结果表明,淀粉酶、糖化酶和纤维素酶的最佳发酵时间是40 h;中性蛋白酶最佳发酵时间是44 h,果胶酶最佳发酵时间是42 h。中性蛋白酶在50℃时活力最高,Mn2+对其有激动作用,最适宜酶解温度为40~45℃、适宜酶解p H为8;糖化酶在35℃时活力最高,Cu2+、Fe3+和Mn2+对其有激动作用,最适宜酶解温度为35℃左右、适宜酶解p H为8.0;果胶酶在40℃时活力最高,Mn2+和Ca2+对其有激动作用,最适宜酶解温度为35~40℃、适宜酶解p H为6.0;纤维素酶在50℃时活力最高,Ca2+和Cu2+对其有激动作用,最适宜酶解温度为40~45℃,适宜酶解p H为7.0。该菌株生产的胞外酶符合水酶法提取植物油脂复合酶制剂的要求,本文为该类菌株的应用奠定理论基础。

The biological characteristics and culture characteristics of Bacillus amyloliquefaciens NCUll6-1 were studied. Nation-standard method and carboxymethyl cellulose saccharification method were used to analyze the enzymes production fastigium and their properties.The result showed that the optimal fermentation time of amylase, amylase and cellulase was 40 h. The optimum fermentation time of the neutral protease was 44 h.The optimum fermentation time of pectinase was 42 h, The neutral protease had the maximum activity at 50 ℃.Mn2＋ was an activator of neutral protease.Its optimum temperature and pH value were 40-45 ℃ and 8 respectively.The glucoamylase had the maximum activity at 35 ℃, and was activated by Ca2 ＋ , Fe3 ＋ and Mn2＋ .Its optimum temperatures and pH value were 35-40 ℃ and 8.0 respectively.The pectase had the maximum activity at 40 ℃,and was activated by Mn2＋ and Ca2＋ .Its optimum temperatures and pH value were 35-40 ℃ and 6.0 respectively.The cellulase had the maximum activity at 50 %, and was activated by Ca2＋ and Cu2＋ .Its optimum temperatures and pH value were 40-45 ℃ and 7.0 respectively.The extracellular enzymes produced by the strain meet the requirements of aqueous enzymatic method and this paper lays a theoretical foundation for the application of this kind of strain.