Phytochemical screening and antioxidant activity of leaves of Amaranthus hybridus L., Corchorus olitorius L and Hibiscus sabdariffa L. grown in northen of Côte d’Ivoire

Our work was based on the study of aqueous and hydroethanol extracts from the leaves of Amaranthus hybridus L. (Amaranthaceae), Corchorus olitorius L. (Tiliaceae) and Hibiscus sabdariffa L. (Malvaceae), and decoction. This work presents for the first time the phytochemical screening and the antioxidant activity of extracts of leaves of these three plants coming from the Cote d’Ivoire. Phytochemical analysis of these extracts revealed the presence of polyphenols and alkaloids in the three leaves. The total phenolic content of the extracts showed variations, between 13.22 and 90.89 mg GAE/g. The hydroethanol extract (90.89 mg GAE/g) and decoction of C. olitorius (57.89 mg GAE/g) had the most elevated contents. The evaluation of the reducing power with DPPH method revealed that the hydroethanol extract of C. olitorius was the most active (IC50 = 45.58 µg/mL). This result was in agreement with that obtained by FRAP method.