Quantitative Determination of the Radical Scavenging Activity of Antioxidants in Black Tea Combined with Common Spices Using Ultraviolet-Visible Spectroscopy

Abstract

Teas and spices are widely known to have high antioxidant content and reactivity. The antioxidant properties are derived from the contained phenolic compounds. The health benefits gained from consuming various teas and spices differ based on the structure of the antioxidants present. When the two are mixed, the net antioxidant effect can change. In this study, the antioxidant properties of black tea combined with cloves, cinnamon, ginger, black pepper, chai blend, turmeric, and cardamon were studied using the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radical assay followed by quantitative measurements with an ultraviolet-visible spectrometer. Significant interactions were observed only with cloves and cinnamon but, interestingly, the observed correlations were negative. The number of trolox equivalents in the pure spices studied varied substantially, led by cloves and then cinnamon; the remainder had considerably lower—but similar—levels of antioxidants.

Keywords:

• antioxidants
• spectrophotometry
• spices
• 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radicals
• tea