Study on extraction process and antioxidative activity of total saponins from Globba racemosa Smith roots

The purpose was to explore the optimal ultrasonic extraction conditions of total saponins from Globba racemosa Smith roots, and evaluate the antioxidant activity.On the basis of single factor experiment, 3 factors and 3 level response surface test was adopted. The results showed that the optimum extraction parameters of the total saponins in the Globba racemosa Smith roots were the ratio of liquid to material was 1:30 (g/mL), the particle sizes of sample were 40 mesh and the ultrasonic extraction time was 51 min. According to this process, the total saponins in the Globba racemosa Smith roots were extracted in different habitats, the content of total saponins in Wuchuancounty and Sanducounty were relatively high and stable, with content of 16.88 mg/g and 16.92 mg/g respectively. The antioxidant analysis of using DPPH and ABTS showed that the concentration of extracting in the Globba racemosa Smith roots was proportional to the antioxidant activity. The free radical scavenging rate of the total saponins extract of the Globba racemosa Smith roots was different in different habitats, and the intensity of the free radical scavenging rate was positively correlated with the total saponins content extracted from Globba racemosa Smith roots. It is verified that the antioxidant ability was related to the total saponins content.