Antioxidant Activity and Flavonoid Estimation in Rosa multiflora and Rosa wichuraiana Fruits and Flowers

Abstract

The fruits of Rosa multiflora Thunberg and Rosa wichuraiana Crépin are oriental medicine resources used complementary in management dropsy, edema and nocturnal enuresis in Korea. The objective of the present study was to evaluate the antioxidant activity and the content of kaempferol and quercetin of Rosa multiflora and Rosa wichuraiana fruits and flowers. Crude ethanol extracts of the species’ fruits and flowers from the two Rosa species were fractionized with hexane, ether, ethyl acetate and water, and antioxidant activities of the resulting fractions were evaluated in vitro using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and superoxide anion radical scavenging activity. The content of kaempferol and quercetin was quantified by high-performance liquid chromatography (HPLC) analyses. The water fraction of R. multiflora and ethyl acetate fraction of R. wichuraiana exhibited the highest DPPH free radical scavenging activity, which are generally proportionally to concentration, and the ethyl acetate fraction of fruit and ether fraction of the flower from the two Rosa species exhibited the highest superoxide anion radical scavenging activity. Meanwhile, the ethyl acetate and ether fraction of flower and fruit from the two Rosa species contained high level content of kaempferol and quercetin. These findings indicate that the antioxidant activity and the content of kaempferol and quercetin of Rosa multiflora and Rosa wichuraiana is dependent on solvent fraction. Moreover, both Rosa species fruits and flowers are promising sources of antioxidant phytochemicals, which further supports their use in complementary oriental medicine resource in Korea.