Antioxidants activities, HPTLC and HPLC/MS characterization of some phenolic acids of <i>Grangea maderaspatana</i> roots extracts from Burkina Faso

Grangea maderaspatana belonging to Asteraceae family is used for its pharmacological properties. The aim of this study is a bio-guided antioxidant compounds characterization of Grangea maderaspatana roots extracts. Extracts were obtained using hexane, dichloromethane, ethyl acetate and methanol. Each crude extract was tested for its free radical scavenging activity using DPPH method. Ethyl acetate extract was found to have the most antioxydant activity with IC50=64.720 µg/mL. This active extract was passed through to column chromatography fractionation to yield seven sub-fractions of which sub-fraction F’’’6 was the most active (IC50=2.897µg/mL). HPTLC and HPLC/MS analysis showed that this sub-fraction mainly contained phenolic acids of which eight were identified as chlorogenic acid (5-caffeoylquinic acid), 1,3,5-tricaffeoyl-4- succinoylquinic acid, 3,4,5-tricaffeoylquinic acid, 1,5-dicaffeoyl-4-succinoylquinic acid, 1,3- dicaffeoyl-5- fumaroylquinic acid, 3,5-dicaffeoyl-1-fumaroylquinic acid, 1,5-dicaffeoyl-4-fumaroylquinic acid and 1- fumaroyl-3,5- dicaffeoyl-4-succinoylquinic acid. Thus, it can be seen from the present study that Grangea maderaspatana roots extract mainly contain phenolic acids and could be used as natural oxidant.