响应面分析法优化酸性蛋白酶固态发酵培养基的研究

用响应面分析法(采用中心组合一致精度的设计)对影响土曲霉产酸性蛋白酶固态发酵培养基的4个主要影响因素(麸皮与豆粕比例、硫酸铵、硝酸钠、磷酸二氢钾)进行了优化,考察了各因素及其交互作用对酸性蛋白酶酶活的影响。用SAS9.1.3软件模拟二次多项式回归预测模型并建立了影响因素与响应值(酸性蛋白酶酶活)之间的函数关系,即回归方程,找到了各因素的最佳水平,即麸皮与豆粕比例为1:0.20、硫酸铵为1.9%、硝酸钠为0.97%、磷酸二氢钾为3.3%,此时酸性蛋白酶酶活为9326U/g。通过验证试验,5次重复试验的平均值为9327U/g,与模型预测值基本一致。

Study on culture medium optimization of solid fermentation producing acidic proteinase by response surface analysis

Response surface analysis(central composite design of uniform precision)was applied to optimize the significant four factors[the ratio of bran and soybean meal,(NH4)2SO4,NaNO3 and KH2PO3] for culture medium of Aspergillus terreus by researching the contributiveness of factors and their interactions to the enzyme activity of acidic proteinase.The functional connection of the factors and response,that is the equation of polynomial regression was established by using SAS 9.1.3 to simulate the predictive model.Through the equation of polynomial regression,the value of optimization was obtained,namely the ratio of bran and soybean meal is 1:0.20;the quantity of(NH4)2SO4 is 1.9%;the quantity of NaNO3 is 0.97%;the quantity of KH2PO3 is 3.3%.Under the optimization,the enzyme activity of acidic proteinase is 9 326 U/g.Through validating test,the average value of five tests is 9 327 U/g.It is identical to the value of predictive model.