Mutagenicities of N-nitrosamines on Salmonella

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Updated: Oct 31, 2026

Chronic Salmonella Infected Mouse Model
09:01

Chronic Salmonella Infected Mouse Model

Published on: May 31, 2010

T Yahagi, M Nagao, Y Seino

    Mutation Research
    |April 1, 1977
    PubMed

    Insights

    This study tested 11 N-nitrosamines for mutagenicity using Salmonella strains. Carcinogenic N-nitrosamines showed mutagenicity on TA100, but not TA98, highlighting strain-specific responses in mutagenicity testing.

    Area of Science:

    • Toxicology
    • Microbiology
    • Genetics

    Background:

    • N-nitrosamines are a class of compounds known for their carcinogenic potential.
    • Assessing mutagenicity is crucial for understanding the genotoxic risks associated with N-nitrosamines.

    Purpose of the Study:

    • To evaluate the mutagenic activity of eleven different N-nitrosamines.
    • To compare the mutagenic responses across two Salmonella typhimurium strains (TA100 and TA98).
    • To investigate the influence of metabolic activation and specific chemical conditions on mutagenicity.

    Main Methods:

    • Utilized Salmonella typhimurium strains TA100 and TA98 for mutagenicity assays.
    • Employed a drug-activating system from rat liver (S-9 Mix) to mimic metabolic activation.
    • Tested N-nitrosamines under varying conditions, including pre-incubation and the presence of dimethyl sulfoxide.

    Main Results:

    • All tested carcinogenic N-nitrosamines were mutagenic on TA100 with S-9 Mix.
    • N,N-diphenylnitrosamine, a non-carcinogen, did not exhibit mutagenicity on TA100.
    • Most N-nitrosamines were not mutagenic on TA98, with N,N-diethylnitrosamine showing weak mutagenicity.
    • Pre-incubation with S-9 Mix was essential for detecting N,N-dimethylnitrosamine mutagenicity.
    • Dimethyl sulfoxide inhibited the mutagenic effect of N,N-dimethylnitrosamine.

    Conclusions:

    • Salmonella typhimurium TA100 is more sensitive to the mutagenicity of carcinogenic N-nitrosamines than TA98.
    • Metabolic activation plays a significant role in the mutagenic potential of N-nitrosamines.
    • Specific assay conditions, such as pre-incubation and the presence of inhibitors, can influence the detection of mutagenicity.

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