Box-Behnken中心组合设计优化酶法提取马齿苋多糖的工艺

Optimization on enzymatic extraction of polysaccharides from Portulaca oleracea L.by Box-Behnken central composite design

采用Box-Behnken中心组合试验设计,以果胶酶添加量、酶解温度、料液比为自变量,以多糖得率和羟基自由基(·OH)清除率为因变量,利用响应面法优化果胶酶酶解提取马齿苋多糖的工艺。结果表明,料液比1∶37(g/ml)、果胶酶添加量10.67 g/kg、酶解温度36.4℃、pH值5.0、酶解时间80 min条件下,马齿苋多糖得率预测值与测定值的相对标准偏差为2.29%,模型拟合度较高。体外抗氧化试验结果表明,马齿苋多糖具有较好的抗氧化性。因此,采用响应面法优化酶法提取马齿苋多糖工艺条件是可行的。

The Box-Behnken central composite design was used in this study.Taking pectinase addition,hydrolysis temperature and solid-liquid ratio as independent variables,the extraction rate of polysaccharides and the clearance rate of hydroxyl radical(·OH)as dependent variables,the response surface method was adopted to optimize the enzymatic extraction process of polysaccharides from Portulaca oleraceae L..The results showed that the optimal conditions were as follows∶the solid-liquid ratio was 1∶37(g/ml),pectinase addition was 10.67 g/kg,hydrolysis temperature was 36.4℃,pH value was 5.0,and enzymolysis time was 80 min.Under the optimal conditions,the relative standard deviation of polysaccharide yield between the predicted value and the measured value was 2.29%,and the model fitting degree was high.The results of antioxidant test in vitro indicated that polysaccharides from Portulaca oleracea L.had better antioxidant properties.Therefore,it is feasible to optimize the extraction conditions of Portulaca oleracea L.polysaccharides by the method of response surface.