Antioxidant activity of polyphenols from Hypericum triquetrifolium Turra.

From the aerial parts of Hypericum triquetrifolium Turra (Guttiferae) 3-8"-biapigenin, quercetin, rutin and chlorogenic acid were isolated. Their structures were elucidated by spectral techniques. Furthermore, the phenolic compounds were tested for antioxidant activity, using an in vitro method based on sodium arachidonoate, bleomycin and thiobarbituric acid with alpha-tocopherol as the reference solution.