Antiradical Activity of Five Plants Used for the Treatment of Type 2 Diabetes in Benin: A Comparative and Analytical Overview

The number of diabetics is increasing year by year in the world and the complications of the disease are debilitating. Type 2 diabetes is closely linked to oxidative stress created by excess fat. Oxidative stress has been shown to induce insulin resistance. The objective of this work is to establish the link between the composition in phenolic compounds and the antiradical activity of five plants treating diabetes in the south and in the center of Benin. Coloration and precipitation processes relevant to each metabolite family were used to identify secondary metabolites. The Folin Ciocalteu technique was used to determine total phenols. Total flavonoids were quantified using the aluminium trichloride technique. The antiradical ability of 2,2-diphenyl-l-picrylhydrazyl(DPPH) was determined. Our results showed that the leaves of three plants contained high level of phenolic compounds; Mangifera indica (29.409 mgGAE/g); Parkia biglobosa (26.909mgGAE/g) and Bambusa vulgaris (23.298 mgGAE/gEx). It is the hydro-ethanolic extracts of these three plants that have shown higher anti-radical activities than that of vitamin C. Bambusa vulgaris (IC50=0.28mg/mL), Parkia biglobosa (IC50=0.3mg/mL), Mangifera indica (IC50=2.5mg/mL), vitamin C (IC50=3.2 mg/mL). The composition in polyphenols and the antiradical activity of these three plants could justify their role in the prevention and treatment of type 2 diabetes and its complications.