Active Composition of Different Solvent Extracts of Rubus crategefolius Bunge. Root and Their Antioxidant Activity in Vitro

The bioactive constituents of Rubus crategefolius Bunge. were extracted with solvent extraction method. The contents of total flavonoids,total saponins and total phenolic acid were also measured. The in vitro antioxidant activity of each extract was determined by DPPH,ABTS and superoxide anion scavenging assays. The results showed that the contents of total flavonoids,total saponins and total phenolic acid of n-buthanol extract were 5.06%,7.41% and 6.18% and it was higher than those of chloroform extract and ethyl-acetate extract. Among the extracts,ethyl-acetate extract showed higher DPPH and superoxide anion scavenging activities and its IC₅₀ were 94.64 μg/mL and 50 μg/mL,respectively. n-Buthanol extract showed higher ABTS scavenging activity than other extracts and IC₅₀ was 66.43 μg/mL. In conclusion,the roots of R. crataegifolius Bunge. contains flavonoids,saponins and phenolic acid. Furthermore,chloroform extract,ethyl-acetate extract and n-buthanol extract of roots of R. crataegifolius Bunge. had shown strong antioxidant activity. The data could provide the theory basis for the developing R. crataegifolius Bunge. as natural antioxidant or functional food.