In this study a novel microwave-assisted extraction(MAE) device was presented. In this newly developed system, a 3/4 wavelength microwave resonance cavity was used as the microwave coupling device for replacing a traditional microwave oven. This device is used to extract flavonoids from Radix et caulis acanthopanacis senticosi. The effects of solvent concentration, microwave forward power and solvent uptake rate on the extraction yield of flavonoids were investigated by using orthogonal experimental design. The results show that the effects of the solvent(ethanol) concentration and solvent uptake rate on the extraction yield of flavonoids are very significant, the effect of the interaction of solvent concentration and solvent uptake rate is significant and the effects of the other factors are general. Under the optimal conditions of MAE the extraction yield of flavonoids by this system is 46% higher than that by Soxhlet method. The RSD of the method was lower than 6%.
