Scavenging effect of various tea extracts on superoxide derived from the metabolism of mutagens

Biosci Biotechnol Biochem. 1998 Sep;62(9):1768-70. doi: 10.1271/bbb.62.1768.

Abstract

We determine the superoxide formed in the self-degradation of mutagens activated by cytochrome enzymes and evaluated the scavenging effect of various tea extracts. Benzo[a]pyrene (B[a]P) and 2-amino-6-methyldipyrido(1,2-a:3',2'-d)imidazole (Glu-P-1) each produced a large amount of superoxide after activation by cytochrome enzymes. However, 2-amino-3-methyl-imidazo(4,5-f)quinoline (IQ), 3-amino-1,4-dimethyl-5H-pyridol(4,3-b)indole (Trp-P-1) and alfatoxin B1 (AFB1) failed to generate a significant amount of superoxide. The addition of a tea extract to the reaction system marked inhibited the derivation of superoxide from Glu-P-1. However, the tea extracts showed weaker inhibition of the B[a]P-mediated formation of superoxide. Among the four teas tested, the oolong tea extract tended to exhibit the strongest inhibitory effect. Our results suggest that the chemopreventive efficacy of a tea extract is partly associated with its antioxidative activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Male
  • Mutagens / metabolism*
  • Plant Extracts
  • Rats
  • Rats, Sprague-Dawley
  • Superoxides / metabolism*
  • Tea / metabolism*

Substances

  • Mutagens
  • Plant Extracts
  • Tea
  • Superoxides