Optimization of Extraction Process for Total Saponins from Rubus parvifolius in Aqueous Two-Phase System by Mixture Design

Abstract:

Objective: To optimize extraction process of total saponins from Rubus parvifolius in aqueous two-phase system. Method: Taking oleanolic acid as index component, ultrasound-assisted coupling ethanol-ammonium sulfate aqueous two-phase system was adopted to extract total saponins.Mixture design in linear constraints was employed with three independent variables including amounts of ammonium sulfate, ethanol and water, while the content of total saponins as dependent variable, mathematical model between index and factors was established by multi-linear regression and binomial fitting, then optimum process conditions were predicted. Result: Optimum process conditions were as follows:ammonium sulfate 11%, ethanol 37%, water 52%;Extraction rate of total saponins was 3.10%, which had relative error of -1.27% with the predicted value of 3.14%. Conclusion: Mixture design facilitated to optimize extraction technology of total saponins from R. parvifolius in aqueous two-phase system, this established model had good predictability.