Effects of pH and Metal Ions

نویسنده

  • Masaaki TABATA
چکیده

metal ions <A13+, Ca2+, Cd2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, K+, Mg2+, Mn2+, Na+, alld Zn2+) on antioxidatiye activities of (-)-epigallocatechin gallate (EGCG) were studied by an oxygen electrode method. The antioxidatiye activities of catechins were high and censtant at pH 6-12, but decreased in acidic and strollg alkaline solutions. Copper(II) ion the most strongly increased the antioxidative activity of EGCG among these metal io"s examined, but iron(II) ion ]argely inhibited the antioxidative activity of EGCG. These effects are discussed considering the formation of metal complexes with catechi"s and the change in oxidation potentials.

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تاریخ انتشار 2018