Comparison of different methods for extracting flavonoids from water chestnut

The best extraction method and process of flavonoids from water chestnut were studied by used ethanol extraction,ultrasonic extraction and microwave extraction. The optimum conditions of three methods were obtained by orthogonal test respectively. Ethanol concentration,stuff-liquid ratio,power of extraction,and time of extraction as several influential factors of orthogonal test,then the flavonoids extraction rate as an indicator. The extraction rate of ethanol extraction is 2.25%,ultrasonic extraction is 3.01%,and microwave extraction is 3.43%. Compared with others methods,microwave extraction have some advantages include high efficiency and short time. The maximum yield of flavonoids with microwave extraction was obtained by dual extraction with 60% ethanol,1/40 stuff-liquid ratio,400W power,and 2 minutes.