CNS activity of the methanol extract of Mallotus peltatus (Geist) Muell Arg. leaf: an ethnomedicine of Onge.

The aim of the present study was to investigate several neuropharmacological effects of the methanol extract and different fractions of Mallotus peltatus (Geist) Muell Arg. var acuminatus (Euphorbiaceae) leaves in Wistar albino rats and Swiss albino mice. General behavior, exploratory behavior, muscle relaxant activity and phenobarbitone sodium-induced sleeping time were studied. The results revealed that the crude extract at 200-300 mg kg(-1) p.o. and its fractions A and B at 50 mg kg(-1) caused a significant reduction in spontaneous activity (general behavioral profile), remarkable decrease in exploratory behavioral pattern (Y-maze and head dip tests), a reduction in muscle relaxant activity (rotarod, 30 degrees inclined screen and traction tests), and also significantly potentiated phenobarbitone sodium-induced sleeping time. The phytochemical study of crude leaf extract revealed the presence of tannin, triterpenoid, flavonoid, sterol, alkaloid and reducing sugar. Further fractionation and purification yielded two major fractions A (ursolic acid) and B (beta-sitosterol) with some fatty acids as the major compounds. The psychopharmacological activity of the crude leaf extracts appeared to be either due to fraction A (50 mg kg(-1)) or a combination of fractions A and B (50 mg kg(-1)) along with some fatty acids present in the n-butanol part of methanol extract of M. peltatus leaf (MEMPL).