Comparative Research on Total Flavonoids Extracted from Tea by Ultrasound Extraction and Traditional Ethanol Extraction

The conditions for the ultrasound-extraction technology of total flavonoids from tea was optimized by orthogonal experimental designs,and compared with the traditional ethanol extraction method.Results showed that ultrasonic method could increase the rate of total flavonoids from tea efficiently,and ethanol concentration(P0.01),extraction times(P0.01)and ratio of liquid to solid(0.01P0.05)has significant effects on flavonoids extraction.The optimal ultrasonic conditions were available in flavonoids extraction from tea as follows:ethanol concentration 90%,extraction times 2 and ratio of liquid to solid 40:1.Comparing with the traditional ethanol extraction method,the rate of total flavonoids is increased by 11.9%.