Polyphenol content and antioxidative activity of various flower petals

The content of polyphenols, anthocyanins, and flavonols in petal extracts were determined spectrophotometrically in 95 kinds of flower petals, and the antioxidative activities of the petal extracts were examined by the decoloration of IR-carotene coupled with the oxidation of linoleic acid. The polyphenol content for each family of flower showed some differences in mean levels, i.e., 8.74% in Theaceae (camellia), 4.78% in Rosaceae (rose), and 1.66% in Compositae (chrysanthemum), which were calculated as gallic acid in 100 g dry matter of petal. The highest content was found to be 14.83% in red Rosa hybrida (Rosaceae). Almost all of the petal extracts showed antioxidative activity, and good correlation between the activity and the level of polyphenol content was observed, suggesting the direct contribution of polyphenols in the antioxidative activity. The highest ob- served in the red Rosa hybrida was as high as 10 times that of BHA. Further examination of correlation of the kind of polyphenol component and genus of family of flower indicated that the activity of the petals of red Rosa hybrida (rose genus) correlated with their anthocyanin content and activity of Compositae (chrysanthemum family) with the flavonol content.