Determination of Flavonoids From Polygo-Num Avculare by Microwave-Assisted Extraction and Spectrophotometry

Flavonoids were extracted from polygonum avculare by microwave-assisted extraction,and its content was determined by spectrophotometry using the rutin as the quality control standard.The effect of extraction temperature,solid to liquid ratio,alcohol concentration and extraction time on content determination were investigated by orthogonal.The optimum conditions are as follows: extraction temperature 80 ℃,the solid to liquid 1∶40,the volume ratio of ethanol 85% and extraction time 7 min.Under the optimum conditions,the average content of flavonoids in polygonum avculare is 2.099 mg/g,average total flavonoids extract ratio is 3.481%,RSD= 0.304%(n=6),and their recovery rate measured are in the range of 94.17% ~99.50%.