Optimization of microwave-assisted extraction of polyphenols in Chinese chestnut kernel by response surface methodology

In order to provide the reference for the Chinese chestnut functional component research,the optimal conditions for Chinese chestnut kernel polyphenols were evaluated by means of response surface methodology.Microwave-assisted extraction(MAE) was applied to extract polyphenols from Chinese chestnut kernel.The effects of four independents variables in terms of ethanol concentration,microwave power,extract time,and solid-liquid ratio on the polyphenols yield were determined.On the basis of single-factor experiments,a quadratic polynomial regression equation of the forecasting model was set up by using Box-Behnken design.The optimal extraction parameters to obtain the highest polyphenols yield were ethanol concentration of 58%,time duration of 54 s,microwave power of 895 W,and a solid-liquid ratio of 1∶30(g/mL).The average experimental polyphenols yield under the optimum conditions was(0.345±0.004)%,which agree with the predicted value of 0.35%.MAE method was employed successfully to extract polyphenols from Chinese chestnut kernel.