摘要
在巨大芽孢杆菌(Bacillus megaterium)发酵产转糖基β-半乳糖苷酶过程中,以单因素试验为基础研究了不同金属离子和表面活性剂对转糖基β-半乳糖苷酶活性的影响,利用Mintab15软件响应面分析法优化在转糖基β-半乳糖苷酶活性最大时的最佳金属离子浓度、表面活性剂的添加量及加入时机。结果表明,发酵培养基中镁离子浓度为0.031%,吐温-80添加量为0.24%,钾离子浓度为0.047%时,最有利于提高转糖基β-半乳糖苷酶的活性且酶的活性最大。为保持产酶过程中β-半乳糖苷酶的最大活性,在菌体生长对数期的初期,OD值为1.6时添加0.2%的吐温-80,添加过早或过晚都会影响转糖基β-半乳糖苷酶的活性。
The effects of metal ions and surfactants on the activity of transglycosylating β-galactosidase were studied by single factor test in the production of transglycosylating β-galactosidase by Bacillus megaterium. The addition amount and adding time of metal ions and surfactants were optimized by response surface analysis （using Mintab 15 system） to achieve the highest activity of transglycosylating β-galactosidase. The results showed that the activity of transglycosylating β-galactosidase could be improved to the highest level when the concentrations of Mg^2＋, Tween-80 and K＋ were 0.031%, 0.24% and 0.047%, respectively. To keep the maximum activity of β-galactosidase during fermentation, 0.2% Tween-80 was added when the OD500 was 1.6.
出处
《中国酿造》
CAS
北大核心
2010年第8期100-104,共5页
China Brewing
