Rodents Salmonella

Lipopolysaccharide (LPS) endotoxins are characteristic Gram-negative outer-cell components which are produced by many cyanobacteria. Although LPS have been characterized and found to be toxic to laboratory animals after isolation from cyanobacteria, their toxicity to rodents is less potent than the endotoxins of enteric pathogens such as Salmonella Typical symptoms of animals suffering from LPS intoxication include vomiting, diarrhoea, weakness and death after hours rather than minutes. 

Lewis DFV, loannides C, Parke DV. Validation of a novel molecular-orbital approach (COMPACT) for the prospective safety evaluation of chemicals, by comparison with rodent carcinogenicity and Salmonella mutagenicity data evaluated by the United States NCI NTP. Mut Res 1993 291 61-77. 

Helma C (2006) Lazy structure-activity relationships (lazar) for the prediction of rodent carcinogenicity and salmonella mutagenicity. Mol Divers 10 147-158... 

Matthew EJ, Spalding JW, Tennant RW (1993) Transformation of BALB/c-3T3 cells via transformation responses of 168 chemicals compared with mutagenicity in salmonella and carcinogenicity in rodent bioassays. Environ Health Perspect 101 347 182... 

Ashby, J. and Tennant, R.W. (1988). Chemical structure, Salmonella mutagenicity and extent of carcinogenicity as indices of genotoxic carcinogens among 222 chemicals tested in rodents by the US NCI/NTP. Mutation Res. 204 17-115. 

Zeiger E. 1987. Carcinogenicity of mutagens Predictive capability of the Salmonella mutagenesis assay for rodent carcinogenicity. Cancer Res 47(5) 1287-1296. 

Arochlor 54 was not mutagenic in Salmonella assays it was not genotoxic in rodent assays in vivo. ... 

Stodddard solvent was not genotoxic in a variety of assays including Salmonella typhimurium, a mouse lymphoma mutation assay, rodent bone marrow cytogenic tests, and rodent dominant lethal tests." ... 

Triethanolamine was not genotoxic in a variety of assays." It was not mutagenic in Salmonella typhimurium and did not induce sister chromatid exchanges or chromosomal aberrations in vitro. In vivo there was no increase in the frequency of micronucleated erythrocytes in treated rodents. 

T. Dresselaers, J. Theys, L. Dubois, W. Landuyt, P. Van Hecke, P. Lambin, Evaluation of salmonella-based suicide gene transfer in a rodent tumor model using in vivo 19F MR spectroscopy. Proc. Inti. Soc. Mag. Reson. Med. (2006) p. 3175. 

Reddy, J.K., Moody, D.E., Azamoff, D.L. Rao, M.S. (1976) Di-(2-ethylhexyl)phthalate an industrial plasticizer induces hypolipidemia and enhances hepatic catalase and carnitine acetyltransferase activities in rat and mice. Life Sci., 18, 941-945 Reddy, J.K., Reddy, M.K., Usman, M L, Lalwani, N.D. Rao, M S. (1986) Comparison of hepatic peroxisome proliferative effect and its implication for hepatocarcinogenicity of phthalate esters, di(2-ethylhexyl) phthalate, and di(2-ethylhexyl) adipate with a hypolipidemic drag. Environ. Health Perspect., 65, 317-327 Rexroat, M.A. Probst, GS. (1985) Mutation tests with Salmonella using the plate-incorporation assay. Prog. Mutat. Res., 5, 201-212 Rhodes, C., Orton, T.C., Pratt, I.S., Batten, P.L., Bratt, H., Jackson, S.J. Elcombe, C.R. (1986) Comparative pharmacokinetics and subacute toxicity of di(2-ethylhexyl) phthalate (DEHP) in rats and marmosets extrapolation of effects in rodents to man. Environ. Health Perspect., 65, 299-307... 

Blake BW, Enslein K, Gombar VK, et al. 1990. Salmonella mutagenicity and rodent carcinogenicity quantitative structure-activity relationships. Mutat Res 241(3) 261-271. 

Acrylonitrile is mutagenic in vitro, in Salmonella systems, bioactivation (to cyanoethylene oxide) is required, but in Escherichia coli and in rodent systems, bioactivation by an added microsomal system is not required. The results of genotoxicity experiments in vivo have in most cases been negative, although acrylonitrile is mutagenic in Drosophila. 

Roldan-Arjona, T., Garcia-Pedrajas, M.D., Luque-Romero, F.L., Hera, C. Pueyo, C. (1991) An association between mutagenicity of the Ara test of Salmonella typhimurium and carcinogenicity in rodents for 16 halogenated aliphatic hydrocarbons. Mutagenesis, 6, 199-205... 

In addition to the rodent bioassay, the aromatic amines have been studied in the shorter term test Salmonella typhimurium mutagenicity as well as in a variety of acute toxicity assays. A number of QSARs have been generated from such data. The work of Hansch in recent years has demonstrated that the comparison of the QSAR models obtained in different systems, by putting them in a wider perspective, can provide useful clues in the study of the mechanisms of action of individual chemical classes, and can give precious hints on how appropriate the specific models and parameters selected are (Hansch, 2001 Hansch et al., 2002). An exercise of the mechanistic comparison of QSARs has been performed on aromatic amines (Benigni and Passerini, 2002). The results are detailed below. 

The QSARs for the potency of the active aromatic amines in Salmonella typhimurium were not suitable to differentiate the inactives from the actives, and appropriate QSAR models were derived. The QSAR models specific for the separation were based on electronic and steric terms, and hydrophobicity was not found to be significant (Benigni et al., 1998). This result is analogous to that obtained for the rodent carcinogenicity of amines (see above), and provides further evidence of the similarity of the mechanisms of action in Salmonella and rodents. This similarity obviously applies only to the first steps of the process by which the aromatic amines provoke cancer on one side (rodents), and mutations on the other side (bacteria). Once the initial insult to the cells has occurred, the process follows different pathways in the two biological systems the strength of the QSAR model is that it is able to describe quantitatively the first step, which appears to be rate limiting in both systems. 

EU member countries, such as the UK, Germany and the Netherlands, have their own specifications. The European Spice Association (ESA) has a set of quality minima for herbs and spices , but has yet to finalize the cleanliness specification standards for spices and spice products. Extraneous matter and foreign matter should not exceed 1 and 2%, respectively, and should be free from live and/or dead insects, insect fragments and rodent contamination visible to the naked eye (corrected if necessary for abnormal vision). Salmonella must be absent in (at least) 25 g of material yeast and mould, 105/g (target), absolute maximum 106/g E. coli, 102/g (target), absolute maximum 103/g (Table 6.11). 

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