• Toxicological Research
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• v.25 no.1
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• pp.51-58
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• 2009

Carrageenan is a naturally-occurring sulfated polygalactan which has been widely used in the dairy industry and a gelling agent in non-dairy products. In this study, four short-term in vitro genotoxicity assays were investigated to evaluate the potential genotoxic effects of carrageenan. The mutagenicity of carrageenan was evaluated up to a maximum dose of 5 mg/plate in Ames test. There was no increase in the number of revertant colonies compared to its negative control at any dose in all of strains tested. To assess clastogenic effect, the in vitro chromosomal aberration assay was performed using Chinese hamster lung cells. Carrageenan was not considered to be clastogenic in this assay at up to the highest feasible concentration which could be evaluated. The in vitro comet assay and micronucleus test results obtained on L5178Y cells also revealed that carrageenan has no genotoxicity potential, although there was a marginal increase in micronuclei frequencies and DNA damage in the respective micronucleus and comet assays. Taken together, our results indicate that carrageenan was not genotoxic based on four in vitro genotoxicity results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.491-496
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• 1996

This experiment was performed to determine the safety of the Korean red ginseng irradiated with gamma rays with respect to genotoxicity. Ethanol extracts of the 5 and 10 kGy gamma-irradiated red ginseng were examined in two short-term in vitro tests : (1) Salmonella typhimurium reversion assay(Ames test) in strain TA 98, TA 100 and TA 102 (2) Micronucleus test in cultured Chinese hamster ovary(CHO) cells. No mutagenicity was detected in the two assays with or without metabolic activation. It was suggested that the Korean red ginseng irradiated with gamma rays did not cause genotoxicity in vitro. Further tests of genotoxicity in vivo, chronic and reproductive toxicity should be carried out to determine whether it is safe to irradiate Korean red ginseng with practical doses of gamma rays.

• Toxicological Research
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• v.24 no.4
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• pp.321-328
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• 2008

Smoke flavors based on the thermal decomposition of wood have been applied to a variety of food products as an alternative for traditional smoking. Despite its increasing use, the available genotoxicity data on wood smoke flavors (WSF) are still controversial. Thus, potential genotoxic effects of WSF in four short-term in vitro genotoxicity assays were investigated, which included the Ames assay, chromosomal aberration assay, micronucleus test and the alkaline comet assay. WSF did not cause any mutation in the Ames assay using five tester strains at six concentrations of 0.16, 0.31, 0.63, 1.25, 2.5 and 5 ${\mu}l/plate$. To assess clastogenic effect, the in vitro chromosomal aberration assay was performed using Chinese hamster lung cells. No statistically significant increase in the number of metaphases with structural aberrations was observed at the concentrations of 1.25, 2.5, and 5 ${\mu}l/ml$. The in vitro comet assay and micronucleus test results obtained on L5178Y cells also revealed that WSF has no genotoxicity potential, although there was a marginal increase in micronuclei frequencies and DNA damage in the respective micronucleus and comet assays. Taken together, based on the results obtained from these four in vitro studies, it is concluded that WSF is not a mutagenic agent in bacterial cells and causes no chromosomal and DNA damage in mammalian cells in vitro.

• Toxicological Research
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• v.34 no.4
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• pp.303-310
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• 2018

The methods of applied genetic toxicology are changing from qualitative hazard identification to quantitative risk assessment. Recently, quantitative analysis with point of departure (PoD) metrics and benchmark dose (BMD) modeling have been applied to in vitro genotoxicity data. Two software packages are commonly used for BMD analysis. In previous studies, we performed quantitative dose-response analysis by using the PROAST software to quantitatively evaluate the mutagenicity of four piperidine nitroxides with various substituent groups on the 4-position of the piperidine ring and six cigarette whole smoke solutions (WSSs) prepared by bubbling machine-generated whole smoke. In the present study, we reanalyzed the obtained genotoxicity data by using the EPA's BMD software (BMDS) to evaluate the inter-platform quantitative agreement of the estimates of genotoxic potency. We calculated the BMDs for 10%, 50%, and 100% (i.e., a two-fold increase), and 200% increases over the concurrent vehicle controls to achieve better discrimination of the dose-responses, along with their BMDLs (the lower 95% confidence interval of the BMD) and BMDUs (the upper 95% confidence interval of the BMD). The BMD values and rankings estimated in this study by using the EPA's BMDS were reasonably similar to those calculated in our previous studies by using PROAST. These results indicated that both software packages were suitable for dose-response analysis using the mouse lymphoma assay and that the BMD modeling results from these software packages produced comparable rank orders of the mutagenic potency.

• Molecular & Cellular Toxicology
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• v.2 no.3
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• pp.176-184
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• 2006

The controversy on genotoxicity of molinate, an herbicide, has been reported in bacterial system, and in vitro and in vivo mammalian systems. To clarify the genotoxicity of molinate, we performed bacterial gene mutation test, in vitro chromosome aberration and mouse lymphoma $tk^{+/-}$ gene assay, and in vivo micronucleus assay using bone marrow cells and peripheral reticulocytes of mice. In bacterial gene mutation assay, no mutagenicity of molinate ($12-185{\mu}g/plate$) was observed in Salmonella typhimurium TA 98, 100, 1535 and 1537 both in the absence and in the presence of S-9 metabolic activation system. The clastogenicity of molinate was observed in the presence ($102.1-408.2\;{\mu}g/mL$) of metabolic activation system in mammalian cell system using Chinese hamster lung fibroblast. However, no clastogenicity was observed in the absence ($13.6-54.3\;{\mu}g/mL$) of metabolic activation system. It is suggested that the genotoxicity of molinate was derived some metabolites by metabolic activation. Molinate was also subjected to mouse lymphoma L5178Y $tk^{+/-}$ cells using microtiter cloning technique. In the absence of S-9 mixture, mutation frequencies (MFs) were revealed $1.4-1.9{\times}10^{-4}$ with no statistical significance. However, MFs in the presence of metabolic activation system revealed $3.2-3.4{\times}10^{-4}$ with statistical significance (p<0.05). In vivo micronucleus (MN) assay using mouse bone marrow cells, molinate revealed genotoxic potential in the dose ranges of 100-398 mg/kg of molinate when administered orally. Molinate also subjected to acridine orange MN assay with mouse peripheral reticulocytes. The frequency of micronucleated reticulocytes (MNRETs) induced 48 hr after i.p. injection at a single dose of 91, 182 and 363 mg/kg of molinate was dose-dependently increased as $10.2{\pm}4.7,\;14.6{\pm}3.9\;and\;28.6{\pm}6.3\;(mean{\pm}SD\;of\;MNRETs/2,000\;reticulocytes)$ with statistical significance (p<0.05), respectively. Consequently, genotoxic potential of molinate was observed in in vitro mammalian mutagenicity systems only in the presence of metabolic activation system and in vivo MN assay using both bone marrow cells and peripheral reticulocytes in the dose ranges used in this experiment. These results suggest that metabolic activation plays a critical role to express the genotoxicity of molinate in in vitro and in vivo mammalian system.

• Journal of Food Hygiene and Safety
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• v.20 no.1
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• pp.18-21
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• 2005

These observations were performed to investigate the safety of the natural herbs (Rhus-II) in respect of genotoxicity. This substance was examined in two in-vitro tests: (1) Salmonella typhimurium reversion assay (Ames test) in strain TA 98, TA 100, TA 1535 and TA 1537, (2) in vitro chromosome aberration test in cultured Chinese hamster ovary (CHO) cells. In the reverse mutation test, Rhus-II did not induced mutagenicity in Salmonella typhimurium reversion assay(Ames test) with or without metabolic activation. In the chromosome aberration assay using CHO cells, there was no increased incidence of structural and numerical aberrations with or without metabolic activation. These results indicated that, the Rhus-II had no genotoxicity.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.817-820
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• 2006

The potential genotoxicity of methylsulfonylmethane, a crystalline organic sulfur, derived from chemically modified lignin from plants was evaluated using in vitro and in vivo assays. In the bacterial reverse mutation test using Salmonella typhimurium TA98, TA100, TA1535, and TA1538, methylsulfonylmethane did not induce any significant increase of His' revertants. In the in vitro chromosome aberration test using Chinese Hamster Lung (CHL) cells, no aberration effects were seen. In the in vivo evaluation using a micronucleus test, negative results were obtained. Accordingly, the results indicated that methylsulfonylmethane is not genotoxic and its use is unlikely to present a potential hazard.

• Herbal Formula Science
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• v.14 no.1
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• pp.141-167
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• 2006

The genotoxicity of water extract of Bojungikkeehapdaechilki-tang was tested by In Vitro Chromosome Aberration Test. Bacterial Reverse Mutation Assay and Micronucleus test according to OECD Guidelines and KFDA Guidelines. The obtained results were as follows : 1. Chromosome Aberration Test: In Vitro Chromosome Aberration Test of Bojungikkeehapdaechilki-tang extracts was carried out using cultured Chinese hamster lung cells in the presence and absence of metabolic activation system(S-9 mix). No significant changes in the number of aberrant metaphases having structural and number of aberrations were detected in Bojungikkeehapdaechilki-tang extracts treated groups. 2. Bacterial Reveres Mutation Assay: Bojungikkeehapdaechilki-tang extracts was evaluated for its potential to induce reverse mutation in the histidine auxotroph strains of Salmonella typhimurium such as TA100, TA1535, TA98 and TAl537 and the tryptophan auxotroph strain of Escherichia coli WP2 uvrA. No significant changes in the number of revertant colonies compared to its negative control were detected in Bojungikkeehapdaechilki-tang extracts treated groups against all 5 strains. 3. Micronucleus test: Micronucleus test of Bojungikkeehapdaechilki-tang extracts were performed using specific pathogen free 7-week old male ICR mouse. No significant changes in the number of micronucleated polychromatic erythrocytes among 2000 polychromatic erythrocytes compared to negative control were detected in all Bojungikkeehapdaechilki-tang extracts treated groups. In summarized above-mentioned results, it is concluded that Bojungikkeehapdaechilki-tang extracts have not genotoxicity against In Vitro Chromosome Aberration Test, Bacterial Reverse Mutation Assay and Micronucleus test.

• Korean Journal of Environmental Agriculture
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• v.33 no.2
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• pp.138-143
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• 2014

BACKGROUND: Azadirachta Indica extract(AIE) and Sophorae radix extract(SRE) are widely used as environment-friendly organic materials of plant origin in South Korea. METHODS AND RESULTS: In this study, the in vitro micronucleus(vitMN) tests of two samples of AIE and SRE were conducted to evaluate their genotoxicity using the Chinese hamster lung(CHL) cell. This study was composed of two parts; cytochalasin B(cyto B) test and non-cyto B test. Mitomycin C and colchicine were used as positive controls. As a result, the incidence of micronucleus(MN) in all AIE and SRE treated groups increased in dose-dependent manner, but were less than 2.2% in 1,000 binucleated cells. In addition, there were no significant increases of MN incidence in all AIE and SRE treated groups, compared with the negative control group. CONCLUSION: Therefore, we suggest that AIE samples and SRE samples used in this study may have no genotoxicity in the in vitro micronucleus test using the CHL cells. In our previous study, we reported that AIE and SRE did not cause genotoxicity in Ames test. According to the genotoxicity battery system, we concluded that AIE and SRE used in this study have no genotoxic effects to humans.

• Biomolecules & Therapeutics
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• v.11 no.3
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• pp.190-195
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• 2003

To assess the genotoxicity of AS6, several classical toxicological tests were performed. In Ames test, AS6 did not show any transformation of revertant with or without S-9 metabolic activating system, indicating the lack of mutagenic effect of the compound. To assess clastogenic effect, in vivo micronucleus and in vitro chromosomal aberration assays were performed using male ICR mice and Chinese hamster lung (CHL) fibroblast cells, respectively. Chromosomal aberration was not induced regardless of the presence of S-9 metabolic activating system. In addition, AS6 did not cause any increase in the incidence of micronucleated polychromatic erythrocytes at any of the dose levels, suggesting little clastogenicity in vitro or in vivo. Taken together, these results demonstrate that AS-6 has no mutagenic effect in our test system.