Optimization of enzymatic-assisted ultrasonic extraction process of total flavonoids from Sedum aizoon L. and its antioxidant activity

Abstract

In order to optimize the enzymatic-assisted ultrasonic extraction method of total flavonoids from Sedum aizoon L., the effects of solid-liquid ratio, ethanol concentration, extraction temperature, extraction time, and ultrasound power on the extraction rate were investigated by single factor experiment. The optimum technological conditions for enzymatic-assisted ultrasonic extraction of total flavonoids from Sedum aizoon L. were as follows: solid-liquid ratio 1:55 (g/mL), ethanol volume fraction 60%, extraction temperature 45°C, extraction time 2 5 min, and ultrasound power 150 W. Under these conditions, the extraction rate of total flavonoids from Sedum aizoon L. could reach 10.77%. The antioxidant activity of flavonoids from Sedum aizoon L. was positively correlated with the concentration, and the greater the concentration, the stronger the antioxidant capacity. At a concentration of 0.96 mg/mL, the scavenging rate of the DPPH• radical reached 67.5%. The scavenging rate of the ABTs+• radical reached 55.8% at a concentration of 1.92 mg/mL.