响应面法优化藜麦总皂苷提取工艺研究

Extraction of Total Saponins of Quinoa by Response Surface Methodology

采用响应面法优化乙醇回流法提取藜麦总皂苷条件。在单因素试验基础上,选择提取溶剂乙醇体积分数、液固比、提取温度和提取时间为自变量,进行四因素三水平Box-Behnken中心组合设计,以总皂苷含量为指标,采用响应面法(RSM)分析4个因素对响应值的影响。方差分析结果表明:回归模型较好地反映藜麦总皂苷含量与乙醇体积分数、液固比、提取温度和提取时间之间的关系。试验结果表明,最优提取条件为乙醇体积分数90%,液固比78∶1,提取温度72.0℃,提取时间125 min,回归模型预测值与实际值之间有较好的拟合度(R2=0.973 9)。在此提取条件下藜麦总皂苷含量为1.580 g/100 g,与预测值的相对误差为0.57%,精密度RSD为0.279%,回收率96.0%~105.0%,相对标准偏差为4.05%,总皂苷含量响应模型的回归分析、验证试验、精密度和准确性试验证明本方法合理可行。

We used response surface analysis methodology （RSM）to optimize the ethanol reflux extraction condi- tions of total saponins in quinoa. Based on single factor experiments, the concentrations of ethanol in solvent, ratio of liquid to solid, extraction temperature and extraction time were chosen as causal factors ,four- factors -three -levels Box -Behnken central composition experiments design were applied. With the aim of the content of total saponins, RSM was employed to study the effect of these factors on the content of total saponins in quinoa. Variance analysis showed that the regression model fits the relationship of total saponins content to the four process parameters well. The test results showed that the obtained optimum extraction parameters are concentration of ethanol 90% （V/V）, ratio of solvent to raw material 78 ： 1, extraction temperature 72. 0 ℃, extraction time 125 min. The experimental values agree with those predicted from the regression model indicated a good fitness （R2 = 0. 973 9）. The total saponins content was 1. 580 g/100 g,the relative error to the predicted yield was 0. 57% ,the RSD of precision is 0. 279% ,the recovery rate between 96.0% - 105.0% ,relative standard deviations was 4. 05%. It was proved that the method was reasonable and feasible by the regression equation of total saponin content response model, verification test, precision and accuracy test.