Phytochemical Screening and Evaluation of the Antioxidant Potentials of the Stem Bark Extracts of Erythrophleum Africanum (African Blackwood)

Antioxidant agents have been reported to play a significant role in protecting against infections induced by oxidant damage. Erythrophleum africanum have been found to be a reservoir of antioxidant agents. The powdered stem bark sample was macerated with acetone, methanol, and water successively for two weeks by using standard maceration method. The mixtures were agitated with a magnetic stirrer to dissolve the particles, decanted, filtered, and concentrated on rotavapor (R110) at 40 ℃ to obtain the acetone, methanol, and water (aqueous) extracts. By using hydrogen peroxide (H2O2) scavenging assay, the antioxidant potentials of Erythrophleum africanum stem bark extracts was investigated for its free radical scavenging property. The preliminary phytochemical screening of the extracts revealed the presence of seven (7) different secondary metabolites including: saponins, tannins, flavonoids, quinones, glycosides, phenols, and steroids. From the H2O2 scavenging assay, the acetone, methanol, and water (aqueous) extracts showed good dose-dependent free radical scavenging potentials. Both acetone and methanol extracts showed remarkable antioxidant capabilities compared with the standard (ascorbic acid), with the exception of the aqueous extract, which is lower than the standard (ascorbic acid, acetone, methanol, and water: 1.851, 2.412, 2,888, and 1.289). The presence of different secondary metabolites in the stem bark extracts of Erythrophleum africanum proves the use of the plant in folkore medicine and confirm its use as antioxidant.