Assessment of antiradical potential of Calluna vulgaris (L.) Hull and its major flavonoid

BACKGROUND: Antioxidant capacity of the chloroform, ethyl acetate, n-butanol and water fractions of the aerial parts of Calluna vulgaris (L.) Hull (Ericaceae) has been assessed in this study. Antioxidant capacity of the plant was screened by assays of 2,2-diphenyl-beta-picrylhydrazyl, superoxide anion and hydrogen peroxide scavenging, metal-chelating activity and reducing power. Butylated hydroxyanisole was used as reference in all assays; ethylene diamine tetraacetic acid was also used as reference in the assay of metal-chelating activity. Total phenolic contents of the fractions were determined by the Folin-Ciocalteu method. RESULTS: Liquid chromatography/diode array detection/mass spectrometry was used for phytochemical identification of the fractions. Kaempferol-3-O-beta-D-galactoside was found to be the major constituent in the ethyl acetate fraction (37.1 +/- 0.9%), followed by the n-butanol fraction (4.6 +/- 0.1%). High occurrence of antioxidant capacity, with the exception of metal-chelating activity, was observed in the ethyl acetate and chloroform fractions as well as in kaempferol-3-O-beta-D-galactoside. CONCLUSION: Calluna vulgaris and its major flavonoid, kaempferol-3-O-beta-D-galactoside, show high antioxidant capacity in various assays. As far as is known, this is the first report on antioxidant capacity of C. vulgaris and its major flavonoid. (C) 2009 Society of Chemical industry