The Ames/Salmonella mutagenicity assay was used to screen processed oil shale extracts for potentially carcinogenic chemicals. Positive mutagenic activity was detected in organic solvent extracts of all four spent shales tested. This result combined with the fact that most carcinogens (90 percent) have been detected as mutagens in the Ames test, indicates that these extracts contain carcinogens...

Forward mutation to 8-azaguanine resistance and reverse mutation to histidine prototrophy were measured in Salmonella typhimurium after treatment with 16 mutagens of both base-substitution and frameshift classes. The two approaches were found to be equisensitive for all 16 mutagens--i.e., induction of significant mutation occurred at similar concentrations in the forward mutation assay and in t...

Three types of repairless mutant strains of E. coli were tested for mutability by seven representative mutagens. One strain turned out more mutable than the wild type or nonmutable depending on the repair deficiency and the mutagen. This paper describes a simple method for obtaining information on the mechanism of mutation induction by various mutagens such as environmental ones. [The SCI indic...

LANGOVÁ M., POLÍVKOVÁ Z., ŠMERÁK P., BÁRTOVÁ J., BÁRTA I. (2005): Antimutagenic effect of resveratrol. Czech J. Food Sci., 23: 202–208. Evidence exist from population-based and laboratory studies that some phytochemicals have protective effects against tumors or other diseases and reveal antimutagenic activity. We studied the protective effect of the plant phytoallexin resveratrol on the mutage...

Antioxidants are molecules that restrain the process of oxidation. Anti-mutagens are the medium to prevent any DNA transformation. Irreversible DNA damage is caused by mutagens and carcinogens. Defective metabolism occurs due to oxidative stress which can be avoided by antioxidants. The tumour causing ability of nitrosamines, which is commonly referred as chemical carcinogenesis, is been associ...

Overexpression of metallothioneins (MTs) protects some cells against heavy metals, mutagens, anticancer agents, and reactive oxygen species. We have examined the effect of the loss of MT expression on the cytotoxicity of anticancer agents and mutagens using embryonic fibroblast cells from transgenic mice with targeted disruptions of MT I and II genes (MT -/-). MT -/- cells expressed no detectab...

By analogy with the problem of evaluating the genetic risks of radiation, it appears that it will be extremely difficult to assess the mutagenicity for man of the wide range of chemicals to which human populations are currently exposed. Nevertheless, the potential significance of this problem calls for a major effort at such an evaluation.