Application of Response Surface Methodology for Optimizing Extraction Technology of Tea Saponin

Tea saponin (TS) was extracted from tea seed meal by alcohol extraction-acetone precipitation method and vanillin-concentrated sulfuric acid method was chosen to determine the content of TS. On the basis of single factor experiments, the extraction procedure was optimized using response surface methodology, and a mathematical regression model was established for predicting extraction yield of TS at different levels of ratio of liquid to solid, extraction temperature, extraction time. The optimal extraction conditions obtained from this model were as follows: using 80% alcohol as the extraction solvent, extraction at 85.7 ℃ for 3.3 h with a ratio of liquid to solid of 7.25:1. Under these conditions, the actual value of extraction yield of TS amounted to (9.48±0.05)% (n=3), which was in close agreement of the predicted.