Antidiabetic Activity of Fractions of the n-Hexane Extract of Leaves of Eriosema psoraleoides (Lam) G. Don (Leguminosae) on Alloxan-induced Diabetic Albino Rats

Abstract

Diabetes is a chronic disease that is raising health concerns. Eriosema psoraleoides is one of the medicinal plants reported to be used in managing this condition in Eastern Nigeria. This study investigated the effect of four fractions [(n-hexane; n-hexane: dichloromethane (50:50); dichloromethane; and dichloromethane: methanol (95:5)] of the n-hexane leaf extract of this plant on the blood glucose levels of alloxan-induced diabetic rats. The n-hexane extract was obtained by maceration, filtration, and evaporation using a rotary evaporator. Phytochemical screening of the extracts was carried out using standard methods. The extract was fractionated using column chromatography, and ten fractions were obtained. The fractions were pooled together into four fractions based on the similarity in their Rf values. A dose of 200mg/kg of each of the fractions was given orally for 7 days to the alloxan-induced diabetic rats, and plasma blood glucose concentrations determined. Preliminary screening of the extract revealed the presence of flavonoids, steroids, reducing sugars, tannins and combined anthraquinones. Two fractions, the n-hexane: dichloromethane (50:50) and the dichloromethane, produced significant (p 0.05) decrease in blood glucose concentrations in their treated groups compared to that of glibenclamide (standard drug) treated, and the diabetic untreated groups of the diabetic rats. However, the n-hexane and the dichloromethane: methanol (95:5) fractions produced no significant (p 0.05) decrease in blood glucose concentrations. The observed antidiabetic property of the n-hexane: dichloromethane (50:50) and the dichloromethane (100%) fractions suggests that Eriosema psoraleoides could be used in the management of diabetes and this gives credence to its use in ethnomedicine for this purpose.