Studies of the Toxicological Potential of Tripeptides (l-Valyl-l-prolyl-l-proline and l-Isoleucyl-l-prolyl-l-proline): VIII. Assessment of Cytotoxicity and Clastogenicity of Tripeptides–Containing Casein Hydrolysate and Lactobacillus helveticus–Fermented Milk Powders in Chinese Hamster Lung Cells

The objective of this chromosomal aberration test was to assess the mutagenic potential of tripeptides by determining their ability to induce chromosomal aberrations in cultured Chinese hamster lung (CHL) cells. The test agents used in these experiments were (1) powdered casein hydrolysate (CH) and (2) powdered Lactobacillus helveticus-fermented milk (FM). Both test agents contain two tripeptides, L-valyl-L-prolyl-L-proline (VPP) and L-isoleucyl-L-prolyl-L-proline (IPP). CHL cells were cultured and exposed in the presence or absence of a rat hepatic metabolizing system (S9); CH or FM (1250, 2500, 5000 /μg/ml of incubation medium); or positive-control agents, mitomycin C (0.1 or 0.05 /ig/ml) or benzo(a)pyrene (20 /μg/ml). In experiments with CH, cells were incubated for 6 h (either in the presence or absence of S9) or for 24 h (without S9). In experiments with FM, the cells were incubated for 6 h (either in the presence or absence of S9) or for 24 or 48 h (without S9). Neither short-term nor continuous exp...