产α-葡萄糖苷酶菌株的筛选及其培养条件的研究

以6株霉菌为出发菌株发酵提取α-葡萄糖苷酶,以麦芽糖为底物进行转苷试验,用高压液相色谱法分析,筛选出1株产酶活力较高的菌株黑曲霉41873,并对其液体培养产酶条件进行了优化.单因素试验发现最佳碳源为麦芽糖,最佳氮源为豆饼粉,钙离子对产酶有促进作用.为进一步优化产酶条件,采用Plackett-Burman试验设计,从8因素中选出影响产酶的3个重要因素:麦芽糖浓度、接种量和培养时间.利用响应面分析法预测了当麦芽糖浓度为19.8 g/L,培养时间为18.2 h,接种量为0.2 ml时酶活达最大,为549.65 U/ml,通过试验验证,实际酶活分别为529、544U/ml,该模型有较好的预测性.

Study on Screening and Culture Condition of Strains Producing Alpha-transglucosidase

Alpha-transglucosidase was extracted from 6 strains in the lab.Asp.niger 41873 was selected for its higher enzyme activity when using maltose as substrate and HPLC method to analyze.The best enzyme production condition of the strain was also studied.Single factor experiment showed that the best carbon source was maltose,the best nitrogen source was soybean powder and Ca2 promoted the activity of enzyme.In order to optimize the condition,Plackett-Burman(PB) experiment was designed.The 3 important factors influencing enzyme production were selected out from 8 factors,which were maltose quality,inoculate quantity and culture time.With response surface analysis,the predicted maximum enzyme activity was 549.65 U/ml at the condition of 19.8 g/L maltose concentration,18.2 h culture time and 0.2 ml inoculate.The demonstration test showed that the enzyme activity were 529 and 544 U/ml,which means this model could predict precisely.