A comparative study on the free radical scavenging activities of some fresh flowers in southern China

The scavenging activities of the crude aqueous extracts from 69 kinds of fresh flowers in southern China on DPPH, superoxide and hydroxyl free radicals, and their polyphenolic contents, were investigated and evaluated in the paper. The results showed that the extracts of red rose flowers had obviously stronger antioxidant activity when compared to other flowers. Polyphenolic content had significant relationships with the 1,1-diphenyl-2-picrylhydrazyl (DPPH) (r = 0.983, P < 0.01) and superoxide free radical scavenging activity (FRSA) (r = 0.588, P < 0.01), but no significant relationship with hydroxyl FRSA (r = 0.184, P > 0.05) in tested open flowers. However, in tested flower buds, polyphenolic content was correlated well with the DPPH FRSA (r = 0.993, P < 0.01), superoxide FRSA (r = 0.738, P < 0.01), and hydroxyl FRSA (r = 0.737, P < 0.01), respectively. Rose was found to be a promising resource of antioxidant polyphenolics that might contribute to the development of functional food.