响应面法优化章鱼内脏酸性蛋白酶提取条件

Extraction Condition Optimization of Acid Protease From Octopus Viscera by Response Surface Method

首先,以章鱼内脏为原料,通过单因素实验,分析pH值、温度、料液比、抽提时间对提取粗酶液中酸性蛋白酶活性的影响.然后,通过响应面法优化,得到多项式拟合回归方程,并对酶活的预测值和实测值进行验证.最后,测定粗酶液中蛋白酶的种类和活性.结果表明:酸性蛋白酶的最优抽提条件为pH值5.0、温度30℃、时间2.5h、料液比1∶5,由此得到的粗酶液酶活为917.2nkat·g-1,对应比活为28.5nkat·mg-1;响应面回归方程计算的预测值与实际值位于误差范围内,说明该方程具有预测作用;粗酶液中,蛋白酶大部分为酸性蛋白酶,占总蛋白酶76.0%.

To investigate the pH value,temperature,solid-liquid ratio,and extraction time on the acidic protease activity of the crude enzyme solution,the single factor experiment was carried out using octopus viscera as the raw material.The regression was obtained equation by response surface methodology,and the accuracy between predicted and actual values was verified.Finally,the kind and activity of three proteases in the crude enzyme solution were measured.The results showed that the optimum extraction conditions of acid proteases were：pH 5.0,temperature 30℃,time 2.5h,and solid-liquid ratio of 1∶5.Under these conditions,the enzyme activity was 917.2nkat·g^-1,and the specific activity was 28.5nkat·mg^-1.The predicted value and actual value lay within the range of error,which indicated that the regression equation has a predictive role.In addition,most of the total protease,approximately 76.0%,was acidic protease in the crude enzyme solution.