effects of solvents on the in-vitro antioxidant activity of dennettia tripetala g. baker and milicia excelsa (welw.) c. berg root extracts

Background and purpose: the root extracts of dennettia tripetala g. baker and milicia excelsa (welw.) c. berg was investigated for their in-vitro antioxidant activities. materials and methods: the pulverized roots of dennettia tripetala and milicia excelsa were extracted separately by cold maceration using ethyl acetate, methanol, n-butanol and water respectively as the extracting solvents. in-vitro antioxidant, the activity of root extracts was then investigated using dpph model. the results obtained was analyzed using one-way analysis of variance (anova) involving graphpad prism 5 software. results: the antioxidant assay of various extracts, using 2, 2-diphenyl-1-picrylhydrazyl (dpph) radical scavenging model, revealed that the ethanol and n-butanol extracts of d. tripetala had better radical scavenging activity with ic50 values of 2.02 and 0.631 µg/ml for ethanol and n-butanol extracts, respectively. the methanol and ethanol extracts of m. excelsa showed higher radical scavenging capacity with ic50 of 0.194 and 8.84 µg/ml compared to that of the ascorbic acid which had ic50 value of 4.60 µg/ml.conclusion: the radical scavenging ability of the extracts could be attributed to the presence of flavonoids and phenolics.