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Occurrence, identification, and bacterial mutagenicity of heterocyclic amines in cooked food

J S Felton1, M G Knize

  • 1Biomedical Sciences Division, Lawrence Livermore National Laboratory, University of California, Livermore 94550.

Mutation Research
|March 1, 1991
PubMed

Insights

Cooked foods contain potent mutagens called amino-imidazoazaarenes (AIAs). Understanding their structure and human health risks requires isolation, identification, and synthesis for further toxicological evaluation.

Area of Science:

  • Food chemistry
  • Toxicology
  • Organic chemistry

Background:

  • Cooked foods worldwide exhibit potent mutagenic activity in Salmonella bacteria.
  • Assessing human health risks necessitates genotoxic and carcinogenic evaluations of dietary mutagens.
  • Identifying the precise structure and quantity of these mutagens is crucial for risk assessment.

Purpose of the Study:

  • To outline the essential steps for isolating, identifying, and synthesizing dietary mutagens.
  • To highlight the importance of the Ames/Salmonella assay in guiding the purification and identification process.
  • To emphasize the need for synthesized compounds for comprehensive biological assessment.

Main Methods:

  • Utilizing the Ames/Salmonella assay to guide the purification of mutagens.
  • Employing Mass and NMR spectrometry for structural identification of isolated compounds.
  • Synthesizing the exact isomer of identified mutagens for further testing.

Main Results:

  • The predominant mutagens in cooked Western diets are amino-imidazoazaarenes (AIAs).
  • AIAs are found in concentrations ranging from less than 1 to 70 ng/g of meat.
  • These compounds are formed from heating natural precursors like creatinine and amino acids.
  • AIAs are highly potent mutagens, with methyl group configuration significantly impacting activity.

Conclusions:

  • Amino-imidazoazaarenes (AIAs) are potent mutagens found in cooked foods.
  • Structure elucidation and synthesis are critical for evaluating the human health risks of AIAs.
  • Further research is needed to fully understand the toxicological impact of these dietary mutagens.

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