Evaluation of Hypericum perforatum oil extracts for an antiinflammatory and gastroprotective activity in rats.

Oil extracts of Hypericum perforatum L. (Oleum Hyperici) were prepared in three different ways according to the prescriptions from traditional medicine. Variability of constituents and biological activity were evaluated in the obtained oil extracts. The carrageenan-induced rat paw edema test has been used for screening the antiinflammatory activity, while the indomethacin-induced rat gastric mucosa damage test was used for evaluation of gastroprotective activity. All examined oil extracts possessed antiinflammatory and gastroprotective activity. Among them, the oil extract prepared by maceration with 96% ethanol, followed by extraction with sunflower oil by heating on a water bath (extract 2), in a dose of 1.25 mL/kg p.o., exhibited the highest antiinflammatory effect (95.24 +/- 11.66%) and gastroprotective activity (gastric damage score of 0.21 +/- 0.12). The same oil extract had the highest content of quercetin and I3,II8-biapigenin (129 +/- 9 microg/mL and 52 +/- 4 microg/mL, respectively). Quercetin and I3,II8-biapigenin exhibited antiinflammatory activity similar to those of indomethacin as well as significant gastroprotective activity. The results provide evidence for the usage of Oleum Hyperici as an antiinflammatory and gastroprotective agent, which has been based previously only on ethnopharmacological claims.