Evaluation of the anti-radical activity of two plant extracts: Ficus thonningii and Acacia nilotica, used by the korhogo population in the north of the Ivory Coast

Résumé

The objective of this work was to evaluate the anti-radical power of ethanolic and aqueous extracts of Ficus thonningii and Acacia nilotica, two plants widely used by the population of Korhogo, in the north of Ivory Coast. Phytochemical screening was carried out by the tube staining and precipitation method. As for the determination of total polyphenols, it was done using the colorimetric technique of Folin −Ciocalteur then using a calibration line Y= ax + b, while that of total flavonoids and tannins was determined through a spectrophometer with absorbance read respectively at 404 nm with quercetol as standard and 500 nm (catechin as standard). Finally, the antioxidant activity carried out by the DPPH method. The results obtained revealed the presence of several secondary metabolites including polyphenols, flavonoids, anthocyanins and tannins. The 50% free radical inhibitory concentrations (IC50) of the different Acacia nilotica extracts were 0.0044 mg/mL for the ethanolic extract and 0.0047 mg/mL for the aqueous extract. This result is very close to that of vitamin C (0.0036 mg/mL) taken as the reference molecule, while the IC50 of Ficus thonningii are respectively 0.0194 mg/mL and 0.083 mg/mL for the ethanolic extract. and watery. We note that the extracts have good anti-radical power but that the best remains the ethanolic and aqueous extracts of Acacia nolitica.