Processing Comparative of Solvent Extraction and Ultrasonic-assisted Extraction for Polyphenols from Lycium ruthenicum Murr.

The suitable extraction technology of polyphenols from Lycium ruthenicum Murr. was investigated. Single factor experiments and Box-Behnken(BB)experimental design method were adopted to optimize the extraction technology parameters,and the solvent extraction and ultrasonic assisted extraction were compared in this paper. The results showed that the optimum extraction parameters of solvent extraction were:Ethanol volume fraction 70%,liquid to solid ratio 50:1 mL/g,extraction temperature 58 ℃,extraction time 37 min,and the yield of Lycium ruthenicum Murr. polyphenols was 35.9021 mg/g with the RSD to the predicted value was 0.95%. The optimum extraction parameters of ultrasonic assisted extraction were:Ethanol volume fraction 60%,liquid to solid ratio 50:1 mL/g,extraction temperature 36 ℃,extraction time 31 min and ultrasonic power 240 W,and the yield of Lycium ruthenicum Murr. polyphenols was 39.6845 mg/g with the RSD to the predicted value was 0.29%. It was found that the solvent extraction method had more ethanol dosage with 1.16 times than ultrasonic assisted extraction,the extraction temperature 22 ℃ higher and extended the extraction time 16.22% than the latter. Therefore,the ultrasonic-assisted extraction process had advantages of simple process,time-saving,low energy consumption and high efficiency,which would provide foundation for further study of Lycium ruthenicum Murr. polyphenols.