Tea polyphenols as inhibitors of mutagenicity of major classes of carcinogens

• Published in: Mutation Research/Genetic Toxicology Vol. 371; no. 1; pp. 57 - 63
• Main Authors: Weisburger, John H., Hara, Yukihiko, Dolan, Lisa, Luo, Feng-Qi, Pittman, Brian, Zang, Edith
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 04-11-1996
• Subjects: Ames test; Amines - pharmacokinetics; Amines - toxicity; Animals; Antimutagenic Agents - pharmacology; Biotransformation; Black tea; Carcinogens - pharmacokinetics; Carcinogens - toxicity; Cricetinae; Flavonoids; Genotoxic carcinogens; Green tea; Hamster S9 fraction; Inhibition; Mutagenicity; Phenols - pharmacology; Polymers - pharmacology; Polyphenol; Polyphenols; Polyphenon; Rat S9 fraction; Rats; Tea - chemistry; Rat S9 fraction; Polyphenol; Polyphenon; Ames test; Mutagenicity; Inhibition; Black tea; Hamster S9 fraction; Green tea; Genotoxic carcinogens
• ISSN: 0165-1218; 0027-5107
• DOI: 10.1016/S0165-1218(96)90094-4

Previous research suggested that the mutagenicity of some genotoxic carcinogens, mainly heterocyclic amines, was decreased by green or black tea extracts, or tea polyphenol fractions. Thus, it seemed important to test a variety of genotoxic carcinogens with distinct chemical structures and means of biochemical activation as regards modification of mutagenicity in appropriate strains of
Salmonella typhimurium by 3 concentrations of polyphenols 60, 100, or B, standard commercial polyphenol preparations from green or black tea. Polyphenols sharply decreased the mutagenicity of a number of aryl- and heterocyclic amines, of aflatoxin B
1, benzo[
a]pyrene, 1,2-dibromoethane, and more selectively, of 2-nitropropane, all involving an induced rat liver S9 fraction. Good inhibition was found with 2 nitrosamines that required a hamster S9 fraction for biochemical activation. No effect was found with 1-nitropyrene, and with the direct-acting (no S9) 2-chloro-4-methyl-thiobutanoic acid. Thus, with some exceptions, polyphenols considerably decreased the mutagenicity of diverse types of carcinogens.