Phytochemical screening and analgesic effect, in mice, of the methanolic leaf extract of Manniophyton fulvum Mull.-Arg. (Euphorbiaceae)

Medicinal plants continue to attract attention as an alternative form of therapy. Phytochemical screening, analgesic properties and probable mechanism/s of action of the methanol leaf extract of Manniophyton fulvum were carried out following claimed folkloric usefulness in this regard. Standard methods were used to screen for classes of phytochemicals. Acetic acid-induced writhing and hot plate tests in albino mice were used to evaluate the peripheral and central analgesic effects using acetylsalicylic acid and morphine respectively as positive controls, while 50% DMSO served as negative control. Elucidation of the possible mechanism/s of action of the extract was carried using phenoxybenzamine, naloxen, ondansetron, atropine and haloperidol. Alkaloids, saponins, carbohydrates, terpenoids, steroids tannins, and flavonoids were detected in the extract. At 100 mg/kg dose, significant (P<0.01) reduction in pain stimuli, compared to the negative control group in both models was observed. Higher doses of extract (200 and 400 mg/kg) did not produce any significant effect. Observed results suggest that the leaf extract of M. fulvum may have an analgesic effect that is centrally and peripherally mediated at a lower dose compared to the high dose. The findings provide possible scientific basis for the ethnomedicinal use of the plant in several pain conditions.