In vivo antihyperglycaemic activity of crude and partitioned fractions of selected medicinal plants

The incidence of diabetes mellitus is skyrocketing in sub-Saharan Africa and the world at large, with about 8.8% of the adult population currently affected and projected to rise to 9.9% by the year 2045. The currently used drugs are beset with serious side effects, reduced efficacy due to prolonged use and high cost. This study therefore aimed at exploring the use of medicinal plants for the development of cheaper and more effective herbal remedies/plant-derived anti-diabetic drugs. Ethanol extracts of the leaves of three (3) medicinal plants – Bauhinia reticulata (BR), Cassytha filiformis (CF) and Daniella olieveri (DO) were subjected to in vivo anti-hyperglycaemic screening. The BR and CF crude extracts were partitioned because of their promising antihyperglycaemic potentials, using solvents of varying polarities. The partitioned fractions were thereafter evaluated for anti-hyperglycaemic activity. 100 and 200 mg/dL b.w. were the doses of extracts and fractions administered to the experimental animals. Crude ethanol extract of BR had the highest antihyperglycemic activity, as it lowered blood glucose level of experimental mice from 219.80±22.94 mg/dL to 105.40±10.87 mg/dL with percentage blood glucose lowering effect of 52.05±0.53 %, which was higher than that recorded by the standard drug-Metformin (50.88±0.86 %) at dose of 200 mg/kg b.w. There was no significant difference (p>0.05) in the percentage glucose lowering effect of the ethyl acetate and n-hexane partitioned fractions of BR (55.91±0.20 and 55.80±0.68 % respectively), although, the standard drug had a higher percentage glucose lowering effect (65.92±0.87 %) at dose of 200 mg/kg b.w. Further purification of the fractions could yield active compound(s) which could serve as leads in the development of novel anti-diabetic drugs