Optimization of ultrasound extraction of Wolfberry Flavonoids and its antioxidant activities

The solidtosolvent ratio, ethanol concentration, extraction temperature and extraction time were investigated for extracting total flavonoids from wolfberry. The optimal conditions were found to be extracted at the ratio of material to solvent 1:20 (g/mL), 60 ℃ for 40 min with 70% (v/v) ethanol. The D101 macroporous resin was chosen to purify the flavonoids from the crude extracts, the ORAC value of purified flavonoids was enhanced 83.38% than that of the crude one. The Wolfberry were kindly provided by Ningxia Tang Ming Pharmaceutcal Co., Ltd., the herbs were ground with a DFY1000C omnipotent disintegrator (Wenling Dade machinery Co., Ltd., China) to get a relatively homogenous drug powder and then sieved through 100mesh screen. The Wolfberry powder was stored in a desiccator. The standard of Rutin (>98%) was purchased from Bei Na Chuang Lian Biotechnology Institute of Beijing. All other chemical agents were analytical grade. Extraction methods