title: Scavenging effect of various tea extracts on superoxide derived from the metabolism of mutagens.
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.
authors.affiliation: Department of Food Science, National Chung Hsing University, Taiwan, Republic of China. gcyen@mail.nchu.edu.tw
authors.forename: G C
authors.initials: GC
authors.lastname: Yen
authors.forename: H Y
authors.initials: HY
authors.lastname: Chen
mesh_terms: D000818:Animals; D008297:Male; D009153:Mutagens / Q000378:metabolism*; D010936:Plant Extracts; D051381:Rats; D017207:Rats, Sprague-Dawley; D013481:Superoxides / Q000378:metabolism*; D013662:Tea / Q000378:metabolism*
chemical_list: D009153:Mutagens; D010936:Plant Extracts; D013662:Tea; D013481:Superoxides