Antioxidative effects of polyphenols in leaves of Houttuynia cordata on protein fragmentation by copper-hydrogen peroxide in vitro.

The leaves of Houttuynia cordata have been traditionally used as medicinal foods in East Asia. However, there have been few data about the biological effects. The antioxidative effects of polyphenols in the leaves of H. cordata were investigated on protein fragmentation by copper-hydrogen peroxide in vitro. The total polyphenol content in the leaves of H. cordata was 1.14%. The condensed tannin content was 2.46% by vanillin assay and 0.54% by proanthrocyanidin assay. The polyphenols in the leaves of H. cordata inhibited bovine serum albumin fragmentation by copper-hydrogen peroxide. These results demonstrated that the leaves of H. cordata have antioxidative effects on biological damage such as protein fragmentation.