Cellular reactive oxygen species inhibitory constituents of Hypericum thasium Griseb

Four benzophenone derivatives 1-4, a known benzophenone 5 and four known flavonoids were isolated from EtOAc extract of Hypericum thasium. Lucigenin- and luminal-based chemiluminescence assays were employed to monitor the inhibitory activity of these compounds against reactive oxygen species produced by human polymorphoneutrophils.