keywords: Total antioxidant, polyphenols, flavonoids, Vitexdoniana
In this study, the total antioxidant capacity (TAC), total polyphenolic content (TPC) and total flavonoids content (TFC) of aqueous extract fractions of Vitexdoniana leaves were determined. The results obtained from the study revealed that fraction 1 possessed the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (282 µg/ml TE). The decrease observed in the TAC of fractions is in the order; 1>3>2>4>5 and 6. Fractions 5 and 6 have the same TAC (76 µg/ml TE) being the fractions with the lowest TAC. Fraction 2 has the highest concentration of total flavonoids content (TFC) followed by fraction 1 and the lowest TFC was observed in fraction 5. Correlation between total antioxidant capacity and total flavonoids content of different fractions obtained from aqueous extract of V. doniana leaves showed moderate positive correlation (R2 = 0.6549). similarly, total antioxidant capacity and total phenolic content of fractions showed positive correlation (R2 = 0.6423) and correlation between total phenolic and total flavonoids contents of different fractions obtained from ethanol extract of V. doniana leaves showed the strong positive correlation (R2 = 0.981). From the results, it can be deduced that the antioxidant activity of the fractions to a larger extent depends on the phenolic content, especially the flavonoids.
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