ANTIOXIDANT PROPERTIES OF HYMENOCARDIA ACIDA STEM BARK, CRATEVA ADANSONII AND PTEROCARPUS ERINACEUS LEAVES

Abstract

Medicinal plants are considered as rich sources of phytoconstituents which may be useful in drug development. In this study the methanol extracts of Hymenocardia acida stem bark, Crateva adansonii and Pterocarpus erinaceus leaves were screened for their phytochemical constituents and in vitro antioxidant properties using standard procedures. Results revealed the presence of flavonoids, phenols, saponins, and alkaloids in all the plants extracts. Quantitative phytochemical determination of the plants extracts showed that the flavonoid content of extracts ranged between 52.62 ± 0.03 mg/g and 68.31± 0.03 mg/g, phenols; 61.33 ± 0.03 mg/ml and 75.02 ± 0.04 mg/ml and total phytate content; 3.97± 0.02 mg/ml and 9.39 ± 0.03 mg/ml. The antioxidant activity of the plant extracts is in a dose dependent manner. H. acida showed the highest free radical scavenging activity (IC50=128.83 µg/ml), for 1, 1,-diphenyl-2-picrylhydrazyl (DPPH) compared to other extracts and significantly lower (at P < 0.05) than the standard (ascorbic acid) being (IC50 =101.83 µg/ml). It also has a higher lipid peroxidation inhibition (90.91 ± 0.05 %) when compared to other extracts and standard. The result of this study showed that methanol extracts of H. acida, has significantly higher antioxidant activity at P < 0.05 compared to C. adansonii and P. erinaceus. The antioxidant activities exhibited by these plants could be due to the presence of phytoconstituents, and could serve as a source of antioxidant