Teneurs en phénols totaux, activités antioxydantes des macérés et décocté des feuilles de Uvaria chamae P. Beauv. (Annonaceae)

Abstract

Uvaria chamae is a plant of the Ivorian biodiversity used in traditional medicine. Despite the biological and therapeutic virtues of this plant, little information on the total phenol content and antioxidant activity exist. The objective of this study was to evaluate the total phenol content, antioxidant activity of aqueous macerate, B. BAMBA et al. / Int. J. Biol. Chem. Sci. 15(1): 54-67, 2021 55 ethanolic macerate and aqueous decocate of Uvaria chamae leaves. The total phenol content was determined by the Folin-Ciocalteu method. Antioxidant activity was evaluated by the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ORAC (Oxygen Radical Absorbance Capacity) scavenging method. The total phenol content was 110.51 ± 7.18 μg GAE/mg extract, 86.34 ± 1.38 μg GAE/mg extract and 65.80 ± 0.13 μg GAE/mg extract for ethanolic macerate, aqueous decocate and aqueous macerate of Uvaria chamae, respectively. The different macerated and decocted products presented an activity of scavenging of the two free radicals. Concerning the DPPH radical, the ethanolic macerate of U. chamae exerts a significant antiradical activity with an IC50 of the order of 0.08 ± 0.02 mg/ml. With the ORAC method, the ethanolic macerate of U. chamae (3.51 ± 0.15 μmol TE/μg extract) and the aqueous decocate of U. chamae (3.36 ± 0.18 μmol TE/μg extract) show significant antioxidant activity values. On the other hand, the antioxidant activity values of the aqueous macerate of U. chamae (3.04 ± 0.20 μmol TE/μg extract) and the positive control: ethanolic extract of R. officinalis (2.54 ± 0.06 μmol TE/μg extract) are not significantly different (P ˃ 0.05). These results show the existence of a good linear correlation between the total phenol content and the antioxidant power of the different macerated and decocted phenols of this plant. This Ivorian plant could thus be considered as a source of natural antioxidant for medicinal purposes. © 2021 International Formulae Group. All rights reserved.