Ginger (Zingiber Officinale) Decreases Antioxidant Activity of Black and Green Tea

Background: Tea possesses strong antioxidant activity which may protect human body from free radical-induced diseases. The aim of present study was to examine the effect of ginger on antioxidant capacities of black and green tea. Methods: Infusions of black and green tea with different quantities of ginger were prepared and their antioxidant activities investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis-3-ethylenzothiazoline-6-sulphonic acid (ABTS) methods. Results: The addition of ginger decreased DPPH radical scavenging activity of both black and green teas. The higher doses of ginger resulted in the larger decrease in antioxidant activity of the tea. The maximum decrease in antioxidant activity of black and green tea was 53.06% and 27.36%, respectively. Similarly, ginger reduced ABTS radical scavenging activity of black and green tea up to 49.94% and 37.21%, respectively. Conclusion: The results indicated that ginger decreased significantly the antioxidant activity of tea. Further studies are needed to ascertain the exact mechanism of the decreasing effect of ginger on antioxidant activity of the tea.