Study on the extraction of total flavonoids from Gynostemma pentaphyllum by enzymatic-ultrasonic method and the flavonoids antioxidation activities

The effective extraction of total flavonoids and its antioxidant activities from Gynostemma pentaphyllum were studied in the paper.The samples were treated by cellulase and pectinase respectively, and then extracted by ultrasonic extraction. The yield of the flavonoids was 0.498% by the method. The antioxidant activities of flavonoids from Gynostemma pentaphyllum were studied.The results showed that the flavonoids had strong activity for DPPH and hydroxyl radical scavenging, and the reduction ability increased with the concentration in experimental selecting concentration range.