Preliminary evaluation of the combined anticonvulsant activities of ethanol leaf extracts of Newbouldia laevis, Melissa officinalis, and unripe fruit of Musa paradisiaca

Abstract

In the present study, local Nigerian plants (Newbouldia laevis, Melissa officinalis, Musa paradisiaca) used folklorically against epilepsy, were evaluated for combined anticonvulsant activity in combination. Their anticonvulsant activity, individually and in combination was evaluated in mice using the pentylene tetrazole model. The order of decreasing anticonvulsant activity for the individual plants is 200 mg/kg M. paradisiaca (56.00 %) > 100 mg/kg M. paradisiaca (51.48 %) > 200 mg/kg M. officinalis (46.78 %) > 200 mg/kg N. laevis (43.09 %) > 100 mg/kg N. laevis (37.75 %) = 100 mg/kg M. officinalis (37.75 %). The percentage inhibition of the combined extracts shows 50 mg/kg:50 mg/kg ratio NBL/MP had the highest inhibition of 61.17 %. This may justify this ethnomedicinal combination since this was achieved at low doses of the respective constituent herbs. The order of decreasing inhibition by the combinations is 50:50 NBL/MP > 100:100 NBL/MP > 100:100 NBL/MO > 50:50 NBL/MO. None of the animals died. The above notwithstanding, the combinations may afford an enhanced activity in other seizure types. The anticonvulsant activity of the combinations is neither synergistic nor additive. However, the combination (50 mg/kg NBL and 50 mg/kg MP) provided activity comparable to carbamazepine, and may justify its ethnomedicinal use. Other plant combinations may be explored in search of a synergistic anticonvulsant effect.

Keywords: polyherbal, Musa paradisiaca, Newbouldia laevis, Melissa officinalis, anticonvulsant.