基于响应面分析法对烟叶中果胶测定方法的优化

为了对酶解-连续流动法测定烟叶中果胶含量的方法进行优化,采用Box-Benhnken实验设计及响应面分析法对酶解过程中的酶解温度、酶解时间和缓冲液pH值进行优化。结果显示,酶解温度对果胶测定影响最大,缓冲液pH次之,酶解时间影响最小,且最优酶解条件为酶解时间1.9 h、酶解温度56 ℃、缓冲液pH 3.8;在此条件下,果胶具有良好的线性关系(R²=0.999),加标回收率在99.2%~100.9%,相对标准偏差RSD(n=6)<3%;说明Box-Behnken设计结合响应面分析法优化所得的果胶测定方法具有较好的精密度及准确度,适用于烟叶中果胶含量的批量测定。

The Optimization of the Method of Tobacco Pectin Determination Based on the Response Surface Methodology

In order to optimize the method of determining tobacco pectin using enzymolysis-flow method, reaction temperature, enzymatic hydrolysis time and buffer pH were studied through the Box-Benhnken experimental design and response surface methodology. The results showed that reaction temperature had the greatest impact on the determination of pectin, followed by buffer pH, and the enzymatic hydrolysis time comes last. The optimal enzymatic hydrolysis conditions were pH 3.8, time 1.9 h and 56 ℃. Under this condition, the linear relationship of pectin was optimal (R²=0.999), with the recovery of pectin in tobacco ranged from 99.2% to 100.9%, and the RSD(n=6) was less than 3%. This suggested that the optimized enzymatic hydrolysis conditions used by the Box-behnken design and response surface analysis have good precision and accuracy and are suitable for testing large number of samples.