食品科学 ›› 2008, Vol. 29 ›› Issue (12): 439-443.

• 生物工程 • 上一篇    下一篇

β-环糊精葡萄糖基转移酶高产菌株MS-UD2的选育及产酶条件的研究

 郭利伟, 王卫卫, 陈兴都, 李端   

  1.  西北大学生命科学学院;
  • 出版日期:2008-12-15 发布日期:2011-12-08

Study on Screening and Fermentation Conditions of High β-Cyclodextrin Glucanotransferase-producing Strain MG-UD2 of Bacillus alcalophilus

 GUO  Li-Wei, WANG  Wei-Wei, CHEN  Xing-Du, LI  Duan   

  1. College of Life Science,Northwest University,Xi ’an 710069,China
  • Online:2008-12-15 Published:2011-12-08

摘要: 采用紫外线、硫酸二乙酯和UV+DES复合诱变,对一株产环糊精葡萄糖基转移酶的嗜碱芽孢杆菌IS进行诱变育种,获得了产酶能力是出发菌株2.96倍且产酶性能稳定的高产菌株MS-UD2,并利用单因素分析和正交试验获得突变株的最佳产酶培养基组成为:玉米粉2.0%、玉米浆6.0%、K2HPO4 0.15%、MgSO4·7H2O 0.02%;在温度28℃、pH10.0、接种量8%、250ml三角瓶装液量为50ml的发酵条件下,180r/min二级摇瓶振荡培养36h产酶活力达5741.6U/ml。5L发酵罐36h产环糊精葡萄糖基转移酶活力为5920.0U/ml。

关键词: 嗜碱芽孢杆菌, 环糊精葡萄糖基转移酶, 诱变育种, 条件优化

Abstract: The original strain Bacillus alcalophilus IS was mutated with ultraviolet(UV),diethl sulfate(DES) and UV plus DES. A mutant MS-UD2 was obtained,whose β-cyclodextrin glucanothansferase(CGTase) productivity was 2.96 folds as much as that of parent strain. The continuous 10 generations experiments showed that the mutant MS-UD2 is stable in CGTase production. The fermentation conditions for CGTase production were optimized via single-factor test and orthogonal test. The results showed that the optimal conditions are as follows:using fermentation medium consisting of maize powder 2%,corn steep liquor 6%,K2HPO4 0.15% and MgSO4·7H2O 0.02%,incubation temperature 28 ℃,amount of inoculum 8%,pH 10.0,filled medium volume in 250-ml flask 50 ml and adopting shaking incubation for 36 h at 180 r/min. The enzyme activity could reach as high as 5741.6 U/ml,under these conditions,and in 5-L fermentor the enzyme activity could reach 5920.0 U/ml.

Key words: Bacillus alcalophilus; &beta, -cyclodextrin glycanotransferase; strain breeding; fermentation condition optimization;