The research on extraction of flavonoids from tartary buckwheat by microwave and changes of quantity in different growth periods

The method of extracting total flavonoids from the tartary buckwheat was investigated by microwave oven and orthogonal experiment design at three factors.Such as ethanol concentration 40%,60%,80%,solid-liquid ratio1∶15,1∶20,1∶25(W∶V),extracting temperature 40,60,80 ℃.The result showed that optimum extracting condition is aqueous ethanol 60%(V∶V),solid-liquid ratio 1∶20(W∶V),temperature 80 ℃ and time of vibrating extracting 1 h.Finally,the quantity was analyzed,including the total flavonoids of the different tartary buckwheat in different growth periods.The result showed that the quantity of the total flavonoids in period of 3～4 leaves was more than 5～7 leaves,and bloom was more than full-blooming.The quantity of the total flavonoids in Jiujiang-buckwheat was better than other two buckwheat varieties.It is one kind of good material for tartary buckwheat tea making.