Optimization of polyphenol, flavonoid and tannin extraction conditions from Pouzolzia zeylanica L. benn using response surface methodology

Abstract

In this study, the extraction of phenolic compounds from Pouzolzia Zeylanica L. Benn was conducted by using pure water as a solvent. The optimal conditions for the extraction of three phenolic compounds such as polyphenols, flavonoids and tannins were determined by using response surface methodology (RSM). A central composite design (CCD) was applied to investigate the effects of three independent variables, namely the ratio of water-to-dried material (20:1 to 30:1, v/w), temperature (70 to 90oC ) and time extraction (20 to 40 minutes). The dependent variables were total polyphenol content (TPC), total flavonoid content (TFC) and tannin content (TC). A second-order polynomial model was used for predicting the response. Optimized conditions for bioactive compounds extraction, water-to-dried material ratio, time and temperature extraction were 27 (v/w), 30 minutes and 81oC, respectively. The experimental values agreed with predicted values within a 95% confidence interval. Total polyphenol, flavonoid and tannin content extracted by these optimized conditions were achieved (521 mgGAE/100g dried material (DM), 363 mgQE/100g DM and 643 mgTAE/100g DM, respectively).