A Time-Trend Hypoglycemic Study of Ethanol and Chloroform Extracts of Strophanthus hispidus

Abstract

Strophanthus hispidus Del., a plant widely distributed throughout the open African savanna, is used by ethnic, tribal people of Africa for various purposes, including the control of diabetes. To determine whether the plant was effective in the treatment of diabetes, a phytochemical screening and detailed study of ethanol and chloroform extracts of the leaf, stem, and root tissues of the plant were used to determine the effects of these extracts on blood glucose concentrations in laboratory animals. The phytochemical screening indicated the presence of alkaloids, flavonoids, saponins, and cardiac and cyanogenic glycosides. Significant concentration-dependent hypoglycemic effects (p < .05) of both the ethanol and chloroform extracts were observed with the 50% extracts being more effective than the 20% extracts. The ethanol leaf extract showed a higher hypoglycemic effect (60.0%) than other extracts at 1 hour after extract administration. The 50% and 20% chloroform root extracts exhibited more prolonged hypoglycemic effects than those of other chloroform and ethanol extracts. The highest hypoglycemic activity was observed at 1.5 hours after of extract administration, with an increase in blood glucose concentrations noted by 2 hours after extract administration. This study concludes that the leaf and root extracts of this plant could be a source of a potent drug for the management of diabetes, especially in the resource-poor rural communities of Nigeria, and gives credence to the alleged folklore use of extracts of the plant in the treatment of diabetes.