Effect of crude oil pollution on the in vitro antioxidant potential of methanol extracts of Mangifera indica leaf

Pollution continues to be a significant factor for adverse health implication and cause of death globally due to its strong link to oxidative stress. Oxidative stress is a condition of Redox imbalance in vivo leading to oxidative damage by reactive oxygen/nitrogen species. Crude oil and its products in the water bodies of South Eastern Nigeria are a constant source of pollution to the environment. Plants have been used for thousands of years due to their high levels of antioxidants, which help in quenching free radicals damage to effectively treat both acute and chronic disorders. The aim of this study is to investigate the antioxidant status of Mangifera indica leaves in crude oil polluted sites compared to unpolluted sites. The antioxidant status is accessed through the DPPH assay which measures the free radical removal ability and the FRAP assay, which evaluates the reducing power of the extract. The result shows that DPPH radical inhibition (%) was 60.00, 90.00, and 100.00 for Mangifera indica polluted leaf, Mangifera indica unpolluted and ascorbic acid respectively. Similarly Mangifera indica polluted leaf, and Mangifera indica unpolluted leaf also showed significant free radical scavenging action over each other and the FRAP value (µM) was 0.1, 0.2, 1.1 for Mangifera indica polluted leaf, Mangifera indica unpolluted and ascorbic acid respectively. Similarly Mangifera indica polluted leaf, and Mangifera indica unpolluted leaf also showed significant FRAP values over each other. The results reveal important insights into the effect of environmental contamination and the vital role of Mangifera indica owing to its antioxidant properties. The findings indicate that crude oil pollution is real and buttresses the importance of plants in management of diseases.