Prooxidative activities of tea catechins in the presence of Cu2+.

The ability of various tea catechins to generate H2O2 and the hydroxyl radical in the presence of the Cu2+ ion was investigated and compared with the effect of iron ions. The presence of Cu2+ accelerated the generation of H2O2 by EGC, while EGCg with Cu2+ generated a little H2O2. The presence of iron ions inhibited the generation of H2O2 by EGC.