Studies on the antiinflammatory principle of Mentzelia chilensis

A crude aqueous extract of Mentzelia chilensis GAY (Loasaceae), the ethyl acetate extraction thereof as well as the molecular weight fraction <1000 Dalton obtained by ultrafiltration showed antiinflammatory activity on carrageenin induced rat paw oedema. Bioassay guided isolation led to the iridoid glycoside mentzeloside (syn. deutzioside) as an active principle. Mentzeloside showed a marked and significant dose dependent inhibitory activity on carrageenin induced rat paw oedema with an ED₅₀ of 40.4 μg/kg. © 1998 John Wiley & Sons, Ltd.