The ethyl acetate extract of Piliostigma reticulatum leaves was investigated for its antioxidant constituents. Isolated secondary metabolites of the leaves extract include: 2-O-(p-hydroxyphenyl)-5-hydroxy-6-C-methyl-7-methoxychromone (piliostigmin) 1, 6-C- methylkaempferol- 3-methyl ether 2, quercetin 3, quercetrin (quercetin-3-O-rhamnose) 4, and Isoquercetrin (quercetin-3-O-glucoside) 5. These compounds were evaluated for their antioxidant potentials. A rapid test for antioxidants using DPPH (1,1-dipheny-2-picryhydrazyl) TLC screening, demonstrated considerable radical scavenging activity for all the compounds. The DPPH spectrophotometric method was employed for quantitative determination of radical scavenging activity. The activity was expressed as EC50 value, which ranges between 4.68±0.03 and 50.76±1.71 for the flavonoids constituent.
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M.A. Aderogba, E.K. Okoh and T.O. Idowu, 2005. Evaluation of the Antioxidant Activity of the Secondary Metabolites from Piliostigma reticulatum (DC.) Hochst. Journal of Biological Sciences, 5: 239-242.
- Tutour, B.L., 1990. Antioxidative activities of algal extracts, synergistic effect with vitamin E. Phytochemistry, 29: 3759-3765.
- Havstein, B., 1983. Flavonoids a class of natural products of high pharmacological potency. Biochem. Pharmacol., 32: 1141-1148.
- Trouillas, P., C. Fagnere, R. Lazzaroni, C.A. Caliste, A. Marfak and J.L. Duroux, 2004. A theoretical study of the conformational behavior and electronic structure of taxifolin correlated with the free radical scavenging activity. Food Chem., 88: 571-582.