Mutagenicity screening of feed additives in the microbial system

Area of Science:

• Toxicology
• Microbiology
• Genetics

Background:

• Feed additives are commonly used in animal agriculture.
• Assessing the genotoxicity of feed additives is crucial for food safety and regulatory evaluation.
• Previous studies have indicated potential risks associated with certain feed additives.

Purpose of the Study:

• To evaluate the DNA-modifying and mutagenic potential of 18 feed additives.
• To identify specific feed additives that exhibit genotoxic effects.
• To investigate the role of metabolic activation in the mutagenicity of these compounds.

Main Methods:

• Utilized the rec-assay with Bacillus subtilis strains (H17 and M45) to assess DNA-modifying effects.
• Employed the Ames test with Escherichia coli WP2 hcr and Salmonella typhimurium strains for mutagenicity testing.
• Applied a top-agar overlay method for bacterial mutagenicity assays.
• Investigated the influence of metabolic activation using S9 mix, S9 fraction, and blood.

Main Results:

• Carbadox, furazolidone, panazon, and zoalene tested positive in both DNA-modification and mutagenicity assays.
• These four compounds demonstrated mutagenic activity without requiring metabolic activation.
• Zoalene was mutagenic across all tested bacterial strains.
• Nicarbazin, amprolium, and caprylohydroxamic acid showed weak mutagenic effects under specific conditions.

Conclusions:

• Carbadox, furazolidone, panazon, and zoalene possess significant genotoxic potential.
• The mutagenicity of these four additives is independent of metabolic activation.
• Further research and regulatory scrutiny are warranted for these feed additives due to their genotoxic properties.