The Ames Salmonella typhimurium Reversion Assay

Mutagenicity. The mutagenicity of nitro PAHs has been studied most extensively in the Ames Salmonella typhimurium reversion assay ( 5). The mutagenicities of representative nitro PAHs in this assay are shown in Table I. Some of the more important features regarding their mutagenicity can be summarized as follows ... 

Cyclopenta[cd]pyrene (CPP, XXVIII) is a powerful human cell mutagen in strain hlAlv2, 7 times more potent than BaP (Durant et al., 1996 Hannigan et al., 1998), and a strong promutagen in both the Ames Salmonella typhimurium reversion assay (Eisenstadt and Gold, 1978) and the Salmonella typhimurium strain TM677 forward mutation assay (Kaden et al.., 1979) ... 

TA100 see article) without S9 mix ( —S9, direct activity) and with added S9 (+ S9, indirect activity, promutagens) using a preincubation procedure (Yahagi et al., 1977) of the Ames Salmonella typhimurium reversion assay (Ames et al., 1975 Maron and Ames, 1983). 

FIGURE 10.14 Diagram of procedure for the standard Ames Salmonella typhimurium reversion assay for chemical mutagens (Maron and Ames, 1983). 

Much toxicological data are available on this red pigment acute oral toxicity in mice, 90-day subchronic toxicological study, acute dermal irritation and corrosion, acute eye irritation and corrosion, anti-tumor effectiveness, micronucleus test in mice, AMES test Salmonella typhimurium reverse mutation assay), estimation of antibiotic activity, and results of estimation of five mycotoxins. A new patent on Arpink Red was filed in 2001 with claims of anti-cancer effects of the anthraquinone derivatives and apphcations in the food and pharmaceutical fields. 

The Ames salmonella-microsome test is a principal sensitive mutagen screening test. Compounds are tested on the mutants of Salmonella typhimurium for reversion from a histidine requirement back to prototrophy. A positive result is seen by the growth of revertant bacteria (which do not require an external histidine source). A microsomal activation system should be included in this assay. The use of five different bacterial test strains are generally required. 

The bacterial and mammalian cell assays for gene mutation were developed to measure statistically significant increases in the numbers of mutant colonies derived from rare events many millions of exposed cells must be plated out to allow the assessment of mutation frequency. The Salmonella typhimurium reverse mutation assay ( Ames test) is carried out in a variety of different mutant strains selected to identify the various classes of mutation. The test generates many hundreds of Petri dishes for counting and is not practical for profiling. 

No mutagenic activity of basil essential oil was observed in the Ames test for mutagenicity in Salmonella typhimurium strains TA98, TAIOO, or TA102, with or without metabolic activation, or in the Escherichia coli WP2 reversion assay (Beric et al. 2008 Stajkovic et al. 2007). 

Physicochemical properties requked include melting/boiling point, vapor pressure, solubiUty, and flammabiUty/explosion characteristics. The toxicological studies include acute toxicity tests, oral, inhalation, and dermal skin and eye kritation skin sensiti2ation subacute toxicity, oral, inhalation, and dermal and mutagenicity tests. In vitro reverse mutation assay (Ames test) on Salmonella typhimurium and/or E.scherichia coli and mammalian cytogenic test. In vivo mouse micronucleus test. 

Ecoflex (powder) was tested for its mutagenic potential on the basis of its ability to induce point mutations in several bacterial strains Salmonella typhimurium and Escherichia coll) in a reverse mutation assay (Ames test), according to OECD guideline 471. Results revealed that the polyester is not mutagenic to bacteria. 

Phosphine has been reported as negative for induction of reverse gene mutations up to cytotoxic doses in the Ames assay Salmonella typhimurium). Increased chromosomal aberrations were reported in Chinese hamster ovary (CHO) cells exposed to 2500 and 5000 ppm of phosphine without activation with the S9 fraction. Chromosomal aberrations in CHOs were also reported in cells tested with S9 activation at 2500 ppm, but not 5000 ppm. 

JP-4 was tested in the same battery of tests as those described for JP-8, with very similar results (positive solely in the WI-38-cell UDS assay) (Brusick and Matheson 1978b). JP-5 was not mutagenic in the Ames-type reverse-mutation as say in Salmonella typhimurium strains TA1535, TA1537,TA97,TA98, and TA100 in the presence or absence of metabolic activation with rat or hamster liver S9 (NTP 1986). 

Thompson, P.W. (2005) tVS5 Pure reverse mutation assay Ames test" using Salmonella typhimurium and Escherichia coli. Unpublished report prepared by SafePharm Laboratories, Derbyshire, United Kingdom, for the Flavor and Extract Manufacturers Association, Washington, DC, USA. Submitted to WHO by the International Organization of the Flavor Industry, Brussels, Belgium (SPL Project No. 1044/068). 

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