Antiinflammatory flavonoids from Opuntia dillenii (Ker-Gawl) Haw. flowers growing in Egypt.

Opuntia dillenii (Ker-Gawl) Haw. (Family Cactaceae), is used in folk medicine as an antidiabetic and antiinflammatory. The antiinflammatory activity of the alcohol extracts of the flowers, fruits and stems was carried out using the carrageenan-induced rat paw oedema model. The analgesic effect of the same extracts was evaluated using electric current as a noxious stimulus. The alcohol extract of the flowers revealed the most potent antiinflammatory effect and a pronounced analgesic action at a dose of 200 mg/kg. Bioassay-guided fractionation of this extract using VLC followed by Sephadex and paper chromatography, afforded three flavonoid glycosides, namely, kaempferol 3-O-alpha-arabinoside, isorhamnetin-3-O-glucoside and isorhamnetin-3-O-rutinoside. Their identification was based on physical, chemical and spectroscopic data.