响应面法优化藜麦麸皮皂苷热催化水解工艺

Optimization of Thermal Catalytic Hydrolysis Process of Quinoa Husk Saponins by Response Surface Methodology

采用响应面法研究藜麦麸皮皂苷的最佳热催化水解工艺参数,以提高低极性皂苷(Q;出峰物质)的得率,并探究水解转化前后抑菌活性的改变。在单因素实验基础上,筛选出最合适的影响因素中心点,然后选择pH值、温度及加热时间为自变量,以低极性皂苷3-O-α-L-arabinopyranosyl phytolaccagenic acid 28-O-β-D-glucopyranosy ester(Q_(2)出峰物质)含量为响应值,进行响应面法(Response surface methodology,RSM)中的Box-Behnken实验设计,最后得到目标产物与自变量之间的方程式,采用响应面分析法分析响应面图,研究影响因素间的相互作用及最优工艺参数;比较热催化水解前后皂苷溶液对金黄色萄球菌、表皮葡萄球菌、蜡样芽孢杆菌的抑制作用。结果表明,最佳工艺条件为pH12、温度120℃、加热时间1.5 h,在此条件下,Q_(2)出峰物质含量预测值是135.53μg,实际值是138.74μg,回归模型预测值与实际值之间有较好的拟合度(R^(2)=0.9339),转化后的皂苷溶液显示出更强的抑菌活性。引入高温条件及结合pH值,采用高温热催化水解法获得低极性皂苷,为制备低极性藜麦麸皮皂苷提供数据支持。

The optimum technological parameters of thermal catalytic hydrolysis of quinoa husk saponins and the changes of antibacterial activity before and after hydrolysis were studied.On the basis of single factor experiment,the most suitable influencing factor center was selected,then pH,temperature and heating time were selected as independent variables,and the content of 3-O-α-L-arabinopyranosyl phytolaccagenic acid-28-O-β-D-glucopyranosy ester(Q_(2) peak substance) was taken as index,BoxBehnken test method in response surface methodology was designed,the equations between the target product and independent variables were obtained,response surface methodology was used to analyze the thermal catalytic hydrolysis process of quinoa husk saponins.The results show that the optimal process conditions are as follows:pH 12,temperature 120 ℃ and heating time 1.5 h,the predicted value of Q_(2) peak substance content is 135.53 μg,the actual value is 138.74 μg,the regression model has a good fitting degree between the predicted value and the actual value(R^(2)=0.9339).The transformed quinoa husk saponins solution shows stronger antibacterial activity.By introducing high temperature conditions and adopting high temperature alkaline catalytic hydrolysis method,the less polar quinoa husk saporins was obtained.The study provided data support for the production and utilization of less polar quinoa husk saponins.