Abstract

Response surface optimization of flavonoids extraction from two kinds of chinese tea and research on antioxidant effect

Author(s): Li Hui-Duan

Ethanol extraction of total flavonoids from two kinds of Chinese tea, named as Buckwheat tea and Sparrow mouth tea, were studied in this paper. Based single-factor experimental results, the extract processes were optimized by RSM and Box-Benhnken design. The optimum extract conditions were ethanol concentration of 44%, solid-liquid ratio of 40:0.5 mL·g-1, extraction temperature of 63! and time of 2.1h with responding extraction ratio were 21.64% for Buckwheat tea and 19.41% for Sparrow mouth tea. The experimental extraction ratios matched well with the theoretical values by solving the multiple regression equation. RSM have been proved to be an effective technique for optimization extraction process and the fitted quadratic model has a predictive effect on target extracts. The scavenging effect of tea extracts on hydroxyl radicals displayed a significant dose-effect relationship.