IMPACT OF SOLVENT POLARITIES ON ANTIOXIDANT CAPACITY OF SOME MEDICINAL PLANTS

Abstract

It is well established that various extraction factors, including the method, temperature, time, and solvent system, significantly influence the antioxidant quality of plant-derived products. Extraction conditions are an important factor in the process of obtaining bioactive compounds from plant matrix. Previously, extraction of the plant materials was carried out with Polar (methanol and ethanol) solvents via maceration and thereafter assayed for its antioxidant capacity. In this study, solvents of gradient polarity were used to fractionate the crude extracts of ten (10) plant materials and thereafter assayed using an in-vitro DPPH assay for their antioxidant capacity. Findings revealed that one (1) of the ten (10) plant materials gave fractions that were very prominent in scavenging free radicals across the non-polar and mid-polar solvents which was supported by the IC50 values obtained (ASH= 0.77 μg/ml; ASC=0.05 μg/ml; ASE=0.62 μg/ml: CNNB= 0.98 μg/ml; PRRA=0.99 μg/ml). However, the standard ascorbic acid showed better activity (Vit. C = 0.04).