Abstract

Andrianjato Tartin*, Ralaivaon-dratsitonta Jumael Edith Fabrice, Andrianarijaona Mamy, Razanakoto Jacquelin Albert, Rasolofonirina Hubert Xavier, Léa Herilala Rasoanaivo, Randrianasolo Rivoarison

ABSTRACT

Background: Didierea madagascariensis Baill. is a plant endemic of Madagascar. Traditionally, a decoction of its leaves is used to relieve back pain and reduce blood pressure. After childbirth, it is used by women as a bath three months after delivery to promote the closure of the cervix, facilitate the discharge of lochia, and cleanse the uterus.[1,2] Aim of the study: This work aims to evaluate the chemical constituents and antioxidant activity of this plant. Materials and methods: The chemical constituents of the crude ethanolic, hexane, ethyl acetate and butanolic extracts of the leaves were studied. Column chromatography and TLC methods allowed the isolation of products. The structures of the isolated products were identified by concerted analysis of the 1D and 2D NMR spectra and by comparison with the literatures. The hexane, ethyl acetate and butanolic extracts were used for antioxidant activity using DPPH° free radical scavenging. Results: According to this method, crude ethanolic extract of Didierea madagascariensis leaves exhibited an antioxidant capacity (IC50= 6.56 µg / ml), the antioxidant capacity being more powerful than α-tocopherol (11.43 µg / ml), used as standard drug. Its antioxidant capacity is focalised in ethyl acetate extract (IC50= 5.43 μg/ml). The fractionation of the ethyl acetate and butanolic extracts led to the isolation of four phenolic compounds: 7-hydroxyisoformonetin (P1), quercetin (P2), 1,6-dihydroxy-3,7-dimethoxy-2-(3,8'-dimethyloct-2',7'-dienyl)xanthone (P3) and scutellarin (P4).