title: Formation of DNA-damaging and mutagenic activity in the reaction systems containing nitrite and butylated hydroxyanisole, tryptophan, or cysteine.
abstract: It was confirmed by the procedure of rec-assay that DNA-damaging activities were formed in the reaction systems containing nitrite and phenol derivatives including BHA, tryptophan or cysteine under gastric pH conditions. The mutagenic action of the nitrite-BHA, nitrite-tryptophan and nitrite-cysteine systems was also tested according to Ames' method using Salmonella typhimurium TA 1535 and TA 98. The mutagenic activity was observed in the nitrite-tryptophan and nitrite-cysteine systems, though the nitrite-BHA system did not show the activity. The DNA-damaging products were generally labile, i.e., the activity decreased significantly after 1.5 to 2 hours of the reaction, except in the case of the nitrite-BHA system. The DNA-damaging activity in the nitrite-BHA system did not decrease even after 48 hours of the reaction. Nitrosophenol derivatives themselves showed the DNA-damaging activity at pH 1. The active product in the nitrite-BHA system was isolated and the structure was determined to be 2-tert-butyl-quinone. This compound gave a positive rec-assay test, and showed no mutagenesis by Ames' method. The active product from the nitrite-cysteine system was infered to be nitrosocysteine, and the product showed both DNA-damaging and mutagenic activity.
mesh_terms: D000840:Anisoles / Q000494:pharmacology*; D002083:Butylated Hydroxyanisole / Q000494:pharmacology*; D003545:Cysteine / Q000494:pharmacology*; D004247:DNA / Q000037:antagonists & inhibitors*; D009153:Mutagens / Q000302:isolation & purification; D009573:Nitrites / Q000494:pharmacology*; D011995:Recombination, Genetic; D012486:Salmonella typhimurium / Q000187:drug effects; D014364:Tryptophan / Q000494:pharmacology*
chemical_list: D000840:Anisoles; D009153:Mutagens; D009573:Nitrites; D002083:Butylated Hydroxyanisole; D014364:Tryptophan; D004247:DNA; D003545:Cysteine