Comparative hypoglycemic potentials and phytochemical profiles of 12 common leafy culinary vegetables consumed in Nsukka, Southeastern Nigeria.

Background Metabolic disease like diabetes mellitus is on the increase in developing countries due to lack of access to orthodox medicine owing to its high cost. Health benefits of culinary vegetables cannot be overemphasized. This study therefore aims to profile the hypoglycaemic potentials of 12 common leafy vegetables consumed in Nsukka, Southeastern Nigeria and advise diabetic patients accordingly. Methods A total of 75 albino Wistar rats assigned to 15 groups of five rats per group were used for the study. Diabetes was induced in groups 1-14 rats by intraperitoneal injection of alloxan monohydrate (160 mg/kg), and rats in group 15 were not made diabetic. Groups 1-12 rats were treated with aqueous extracts of the vegetables (200 mg/kg), and group 13 rats received glibenclamide at 2 mg/kg and served as standard control. Rats in groups 14 and 15 received distilled water (10 mL/kg) to serve as negative and normal controls, respectively. The fasting blood glucose (FBG) values of the rats were determined 3, 6 and 24 h post-treatment. Phytochemical studies on the vegetables were also carried out. Results Results revealed that the hypoglycaemic activities of Gongronema latifolium, Pterocarpus santalinoides, Ocimum gratissimum, Pterocarpus mildbraedii and Vernonia amygdalina were comparable (p>0.05) to that obtained for glibenclamide (standard anti-diabetic drug) while Gnetum africanum and Piper guineense did not show significant hypoglycaemic activities. Phytochemicals such as flavonoids, alkaloids, tannins, saponins, glycosides, and terpenes were present in the vegetables. Conclusions It was concluded that the vegetables possess hypoglycaemic activities at different capacities with G. latifolium being the most potent.