Optimization of extraction of polyphenols from grape seeds by response surface methodology

Objective:To establish optimum conditions for extracting polyphenols from grape seeds.Methods:Polyphenols were extracted from grape seeds by ultrasonic-assisted ethanol extraction.Different influence of ferrous tartrate and Folin-Ciocalteau method was compared.On the basis of single factor experiment, response surface methodology based on Box-Behnken experimental design was used to explore the effect of liquid-to- solid ratio, ultrasonic treatment time, power and temperature on extraction efficiency.Results:The optimum extraction conditions were 13∶1 (mL/g) , 100min, 36W and 45℃ for liquid-to-solid ratio, ultrasonic treatment time, ultrasonic power and temperature, respectively.Under these conditions, the extraction content of polyphenol was 17.22mg/g.Extraction rate was high.Couclusions:Such extraction metod could effectively avoid polyphenol decomposition under temperature and yield was higher.The method could be widely applied in polyphenols extraction.