Phenolic Compound Content and Antioxidant Activity of Extracts from the Leaves of Anogeissus leiocarpus (Combretaceae), a Plant Used in the North of Côte d'Ivoire for the Traditional Treatment of Gastrointestinal Disorders in Broiler Chickens

Abstract

Anogeissus leiocarpus (Combretaceae) (DC.) Guill. & Perr. is a plant found in West Africa, from Senegal to Cameroon and extending to Ethiopia and East Africa. In the north of Côte d’Ivoire, this plant is commonly used by livestock farmers to treat various pathologies, including digestive and gastrointestinal disorders. The aim of this study was to determine the phenolic compound content and antioxidant properties of 70% hydroethanol and aqueous extracts of A. leiocarpus’ leaves. Phenolic compound contents were determined by spectrophotometric methods. Antioxidant activities were assessed using ABTS, DPPH and FRAP tests. The 70% hydroethanolic and aqueous extracts of A. leiocarpus presented roughly equivalent concentrations of total polyphenols (608.41 and 558.25 mg EAG/g respectively). However, the hydroethanolic extract was richer in flavonoids (539.60 mg EQ/g) than the aqueous extract (388.95 mg EQ/g). In addition, the average inhibition rate of the ABTS radical in the presence of the 70% hydroethanol extract was 11.56 µM Trolox equivalent/g, compared with 8.32 µM Trolox equivalent/g with the aqueous extract. The average chelation percentages were 31.93% (70% hydroethanol extract) and 20.92% (aqueous extract). As for the reduction of DPPH radical, the ICs50 for the 70% hydroethanol and aqueous extracts were 4.4 mg/mL and 6.0 mg/mL respectively. This study confirms that Anogeissus leiocarpus is a plant containing phenolic compounds. The presence of these phenolic compounds in this plant, together with its antioxidant activities with low values (IC50), could justify its widespread use by livestock farmers in northern Côte d'Ivoire, particularly those rearing broiler chickens.