Registration Dossier

Administrative data

Endpoint:
cytotoxicity
Type of information:
experimental study
Adequacy of study:
weight of evidence
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
publication
Title:
Inhibitory effects of flavourings on mutagenesis induced by chemicals in bacteria.
Author:
Ohta T, Watanabe M, Watanabe K, Shirasu Y and Kada T
Year:
1986
Bibliographic source:
Food and Chemical Toxicology, 24(1), 51-54

Materials and methods

Test guideline
Qualifier:
no guideline followed
Deviations:
not applicable
Principles of method if other than guideline:
Two bacterial strains were used: E. Coli (uvrA, trpE) and salmonella thyphimurium TA98 (uvrB, hisD).
In brief, bacterial cultures were washed twice and treated with one of the mutagens in phosphate buffer for 15-60 min, after which the cells were washed again to remove the mutagen and then assayed for numbers of mutants and viable cells. Mutagen-treated cells were spread onto semi-enriched
minimal (SEM) agar plates containing a flavouring at an appropriate concentration or onto control plates containing no flavouring.
For E. Coli, the SEM agar medium consisted of Vogel-Bonner E medium supplemented with 0.4% glucose, 1.5% agar and 5% (v/v) liquid nutrient broth, while the supplement for S. Thyphimurium were 0.4% glucose, 1.5% agar and 50 µM biotin.
After appropriate dilution of the bacterial suspension, viable cells were determined on the SEM plates. Plates were incubated at 37°C for 3 days, and
then colonies of trp+ or his+ revertants and viable cells were counted.
GLP compliance:
not specified
Type of method:
in vitro

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
no data

Results and discussion

Details on results:
Ethylvanillin showed a clear antimutagenic effect on 4-NQO-induced mutagenesis in E. Coli.
A pronounced decrease in the number of trp+ revertant colonies was observed on the plates containing ethylvanillin (50-150 µg/ml).
There was no effect with S. thyphimurium TA98.

Applicant's summary and conclusion

Conclusions:
antimutagenic effects of ethyl vanillin on 4-NQO-induced mutagenesis in E. Coli.