紫色红曲霉M-35菌株产淀粉酶发酵条件和培养基配方的优化

以实验室前期从红曲米中筛选的高产淀粉酶紫色红曲霉(Monascus purpureus)M-35菌株为研究对象,将单因素试验结果与响应面分析法相结合,对M-35菌株的发酵条件和培养基配方进行优化。摇瓶发酵单因素试验优化了培养温度、初始pH值、碳源种类和含量、氮源种类和含量、金属离子种类和含量等。采用Minitab 17软件的P-B试验设计法,筛选对淀粉酶活有显著影响的因素为:淀粉含量、蛋白胨含量和NaCl含量。根据P-B试验结果,运用响应面法分析,确定M-35菌株产淀粉酶优化的培养基配方为:淀粉含量7.5%,蛋白胨含量4.0%,NaCl含量0.5%;在此条件下,淀粉酶活最高为276.14 U/m L,较优化前提高约1.57倍。利用优化的培养基配方和条件进行5L发酵罐发酵试验,结果表明,M-35菌株发酵80~116 h,淀粉酶活可稳定在296 U/m L左右。

Fermentation Conditions and Medium Optimizing of Monascus purpureus Strain M-35 Producing High-yielding Amylase

Single factor experiment and response surface methodology was combined to optimize the submerged culture conditions and medium for the production of amylase enzyme using Monascus purpureus strain M-35 as material, which had high yield of amylase and purified from the natural fermentation of red yeast rice. The culture temperature, initial pH, kind and content of carbon source, nitrogen source and content, variety of metal ions, and content were optimize by shake flask fermentation single factor experiment. Using Plackett-Burman (P-B) in Minitab 17, 3 significant effects (C content, N content and NaCl content) on amylase enzyme activity were screened out. According to the P-B experiment results and analysis of response surface methodology in Design Expert, the data showed that C content 7.5 %, N content 4.0 %, NaCl content 0.5%, and the maximum amylase enzyme activity was up to 276.14 U/mL under this condition. Fermentation experiment in 5 L fermenter results showed that amylase enzyme activity was up to 296 U/mL after 80-116 h fermentation using the optimal conditions.