Review: Putative mutagens and carcinogens in foods. VI. Protein pyrolysate products

Abstract

Diet and nutrition may be responsible for 60% of the total cancer incidence for women and greater than 40% for men. Fat, animal protein, and meat consumption are highly correlated with colon cancer incidence. The charcoal broiling of meat and fish yield mutagenic substances. Many findings support the hypothesis that the predominant mutagens are formed by the Maillard reaction. A number of mutagenic compounds have been identified both from cooked foods and from protein pyrolysates. The identified compounds are N-heterocyclic primary amine derivatives of either carbolines, imidazoquinolines, or imidazoquinoxalines. The carboline-type mutagens are structurally related to the known carcinogens 2-acetylaminofluorene (AAF) and 2-aminofluorene (AF), while the imidazoquinoline and imidazoquinoxaline types are believed to resemble 3,2'-dimethyl-4-aminobiphenyl (DMAB). Studies support the theory that these compounds require metabolic activation and are carcinogenic. The major metabolites of several compounds have been identified as the N-hydroxy derivatives. DNA binding was found to be a necessary but not a sufficient condition for mutagenesis. The modified base products have been identified as C-8-guanyl derivatives, resembling adducts formed by the carcinogenic aromatic amines.

Inhibition of aminoimidazoquinoxaline‐type and aminoimidazol‐4‐one type mutagen formation in liquid‐reflux models by the amino acids L‐proline and/or L‐tryptophan

“…Heterocyclic amine mutagens of the aminoimidazoquinoline (IQ) class are produced during the frying and broiling of meats and fish, and during the heating of appropriate substrates in liquid-reflux models [Sugimura and Sato, 1983;Vuolo and Schuessler, 1985;Prival, 1984;Felton et al, 1984;Matsushima, 1982;Grivas et al, 1985;Furihata and Matsushima, 1986;Knudsen, 1986;Jagerstad et al, 19861. Several of these IQ-type mutagens have now been conclusively shown to be multipotential carcinogens in rodents [Tanaka et al, 1985;Hayatsu et al, 1987;Sugimura, 1985;Ohgaki et al, 1986, 19871.…”