Phyto chemical screening and antioxidant activity of the stem bark extracts of Diospyros mespiliformis: a medicinal plant in Bauchi

Abstract

Approximately, about 80 % of rural populations in developing countries rely on traditional medicinal plants for their health care needs. As a result, people have developed their knowledge of these traditional medicines through their experiences and daily observations. In Bauchi, this information is deeply rooted in their culture, transferred from one generation to the next, orally and along gender lines. Diospyros mespiliformis, commonly known as African ebony is a large deciduous tree belonging to the family Ebanaceae, it has a wider range of Ethnomedicinal uses, most of which is yet to be substantiated scientifically. Traditionally, it’s used as an astringent, febrifuge, hemostatic, mild laxative, stimulant, vermifuge and to facilitate child birth. This study was aimed to determine the phytochemical constituents and antioxidant activity of the stem bark extracts of D. mespilifomis. The stem bark was collected within Bauchi Local Government Area, Bauchi State, identified by a botanist, Department of Biological Sciences, ATBU, Bauchi, air dried and ground into fine powder. The fine powder (100 g) was soaked in a 400 ml of 80 % v/v methanol for about 48 hrs. The extraction yield was determined (12.50 % w/w). The crude methanol extract was then partitioned sequentially in petroleum ether and ethylacetate. Standard method was used to screen for the phytochemicals and DPPH radical scavenging assay was employed to determine the antioxidant activity of the solvents extract. The phytochemical screening revealed the presence of alkaloids, tannins, phenolics, flavonoids, saponins, and glycosides, in the crude methanol extracts, while saponins, glycosides, terpenoids and stroids were present in petroleum ether fraction and ethylacetate fraction was also shown to contains tannins, flavoinoids, phenolics and alkaloids. DPPH radical scavenging assay revealed that the ethylacetate extract has the highest antioxidant potential (IC50= 30.69 ± 1.28), followed by methanol extract (IC50= 32.83 ± 1.29) and petroleum ether extract has the least antioxidant potential (IC50 = 43.80 ± 1.83). However the activity of the extracts was found to be less when compared to the standard (Ascorbic acid), IC50 = 25.65 ± 0.80 µg/cm3 at 20 µg/cm3. The results of the study supports the claims of efficacy reported in folk uses of the stem bark of the plant in the treatment of disease caused by free radicals and if further purified can be used to source novel antioxidants.