An experimental study exploring the influencing factors for ultrasonic-assisted extraction of flavonoid compounds from leaves of Amorpha fruticosa L.

In this paper, the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized. In single factor experiments, solid/liquid ratios, ultrasonic power, ethanol concentrations and extraction cycles were experimental factors. Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids. The optimal extraction parameters were solid/liquid ratio 1:50 g/mL, ultrasonic power 316 W, ethanol concentration 50%, 4 extraction cycles. In the optimized condition, the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g.