• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1588-1593
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• 2014

This study evaluated the genotoxic effects of 30 kGy of X-ray irradiation to four foods (chicken, egg powder, dried green onion, and black pepper). In bacterial reversion assay with Salmonella Typhimurium TA98, TA100, TA1535, and TA1537, the X-ray irradiated foods did not show a significantly increased number of revertant colonies in the presence or absence of the S9 metabolic activation system. In chromosomal aberration tests with Chinese hamster ovary (CHO) cells, the X-ray irradiated foods showed no increase in the frequency of chromosomal aberrations. In in vivo mouse micronucleus assay, the X-ray irradiated foods did not show any increase in the frequency of polychromatic erythrocytes with micronuclei. These results indicate that 30 kGy of X-ray irradiation to four foods (chicken, egg powder, dried green onion, and black pepper) showed no genotoxic effects under these experimental conditions.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.383-390
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• 2013

Mistlero C was shown to be non-genotoxic in a series of genotoxicity tests, including a bacterial reverse mutation test and a combined in vivo mammalian erythrocyte micronucleus test. In a bacterial reverse mutation assay, no significant increases in the number of revertant colonies, compared to the negative control, was detected in $5,000{\mu}g/plate$ of Mistlero C. In addition, with Mistlero C, no changes were shown in the number of micronucleated polychromatic erythrocytes (MNPCE) among 2,000 polychromatic erythrocytes compared to the negative control. Mistlero C was administered orally in rats to investigate acute toxicity. The $LD_{50}$ values in rats were above 2,000 mg/kg. In a repeated dose, 13-week, oral toxicity study conducted in rats, no compound-related adverse effects were shown at doses of Mistlero C of up to 1,000 mg/kg body weight/day. The results of these studies support the safe use of Mistlero C in food for human consumption.

• Molecular & Cellular Toxicology
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• v.3 no.2
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• pp.107-112
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• 2007

o-Nitrotoluene is used to synthesize artificial dyes and raw materials of urethane resin. In this study, we have carried out in vitro genetic toxicity tests and microarray analysis to understand the underlying mechanisms and the mode of action of toxicity of onitrotoluene. TA1535 and TA98 cells were treated with o-nitrotoluene to test its toxicity by basic genetic toxicity test. Ames and two new in vitro micronucleus and COMET assays were applied using CHO cells and L5178Y cells, respectively. In addition, microarray analysis of differentially expressed genes in L5178Y cells in response to o-nitrotoluene was analyzed using Affymatrix genechip. The result of Ames test was that o-nitrotoluene treatment did not increase the mutations both in base substitution strain TA1535 and in frame shift TA98. o-Nitrotoluene has not increased micronuclei in CHO cells. But onitrotoluene increased DNA damage in L5178Y cell. Two-hundred two genes were initially selected as differentially expressed genes in response to o-nitrotoluene by microarray analysis and forty four genes among them were over 2 times of log fold changed. These forty four genes could be candidate biomarkers of genetic toxic action of o-nitrotoluene related to induction of mutation and/or induction of micronuclei and DNA damage. Further confirmation of these candidate markers related to the DNA damage will be useful to understand the detailed mechanism of action of o-nitrotoluene.

• Food Science and Preservation
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• v.13 no.4
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• pp.524-529
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• 2006

Gamma irradiation at 30 kGy was applied to cereal powders to evaluate their possible genotoxicity. The genotoxicity of 30 kGy-irradiated cereal powders was evaluated by Salmonella typhimurium reversion assay, chromosomal aberration test and in vivo micronucleus assay. The result were negative in the bacterial reversion assay with S. typhimurium TA98, IA100, TA1535 and TA1537. No mutagenicity was detected in the assay with and without metabolic activation. In chromosomal aberration tests with CHL cells and in vivo mouse micronucleus assay, no significant difference in the incidences of chromosomal aberration and micronuclei was observed between non-irradiated and 30 kGy-irradiated cereal powders. These result indicate that cereal powders irradiated at 30 kGy did not show any genotoxic effect under these experimental conditions.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.4
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• pp.301-307
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• 2011

Purpose: If the tooth structure is damaged, then it is impossible to regenerate the tooth. The materials used to restore the tooth structure are not related to the composition of the tooth. The materials used to restore the structure can't replace the natural tooth because they just fill the defective structure. Calcium phosphate cement remineralizes the dentin and almost replaces the natural tooth, but there are some disadvantages. We conducted basic tests with Biomimetic CPC (Bio-CPC) to make sure of the possibility of the biomaterial to remineralize the defective tooth structure. Methods: In this study, the bioactivity and biocompatibility of Bio-CPC were evaluated for its potential value as the bio-material for regeneration of damaged tooth structure by conducting a cell toxicity assay (WST-1 assay), a cytokinesis-block micronucleus assay, a chromosomal aberration test, total RNA extraction and RT-PCR on MDPC-23 mouse odontoblast-like cells. Results: The in vitro cytotoxicity test showed that the Bio-CPC was fairly cytocompatible for the MDPC-23 mouse odontoblast-like cells. Conclusion: Bio-CPC has a possibility to be a new biomaterial and further study of Bio-CPC is needed.

• Food Science and Preservation
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• v.16 no.5
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• pp.782-788
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• 2009

The genotoxicological safety of gamma-irradiated egg white and yolk was examined to ensure that required safety parameters were met, and in an effort to further apply gamma-irradiation for improvement of the hygienic qualities of eggs. Egg white and yolk were irradiated at 20 kGy, much higher than the legally approved dose (less than 5 kGy), and possible genotoxicity was evaluated using in vitro and in vivo tests. The SOS chromotest employing Escherichia coli PQ37, and a chromosomal aberration test in cultured Chinese hamster lung (CHL) cells, were performed in vitro with or without metabolic activation (S9). An in vivo micronucleus development test was conducted using mouse bone marrow cells. Negative results were obtained in the SOS chromotest. The incidence of chromosomal aberration in CHL cells and the frequency of micronuclear developmentin mouse bone marrow cells treated with irradiated samples were not significantly different from those of non-irradiated controls. Thus, it may be concluded that up to 20 kGy of gamma irradiation applied to egg white and yolk did not show any genotoxic effects under our experimental conditions.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.555-566
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• 1997

This study was carried out to evaluate the cytotoxicity of rock wool fibers(RWFs) such as cell division disturbance, chromosomal and DNA damage, and mutagenicity using cultured cells. RWFs were the man made mineral fibers. In order to find the correlation between the cytotoxicity of RWFs and the phagocytic capacity of cells, the phagocytic processes were observed using scanning electron microscope. Cell division disturbance by RWFs was evaluated by the formation of multinucleated giant cells. The chromosomal damage was evaluated by the micronucleus formation. For the evaluation of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) formation was measured utilizing calf thymus DNA. Mutagenicity was determined by the point mutation of HGPRT and the effect of RWFs on cell transformation was also observed. 1. Compared with the results of chrysotile, RWFs were no or little effect on the cell growth according to the results done by the tests of cell proliferation inhibition and relative plating efficiency. 2. The frequency of multinucleated giant cell formation was increased by the treatment of RWFs and it was dose-dependent. However, the effect of RWFs was weaker than that of chrysotile. 3. The number of micronuclei formed in the RWFs treated cells was between those of cells treated with chrysotile and those of untreated cells. 4. The 2 fold increase in the formation of 8-OH-dG in calf thymus DNA was observed in the cells treated with RWFs in the presence of $H_2O_2$. On the other hand, chrysotile had no effect on the 8-OH-dG formation. 5. RWFs had no effect on the HGPRT point mutation and cell transformation. These results showed that RWFs could induce chromosomal damage, cell division disturbance and oxidative DNA damage in the RWFs treated cells.

• Toxicological Research
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• v.20 no.4
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• pp.365-374
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• 2004

Inhalation toxicity, mutagenicity, and immunotoxicity tests were performed using a smoke generation system to investigate the safety of Herbrette, a tobacco substitute made with the leaves of Perilla frutescens. ICR mice were exposed to nicotine-free Herbrette smoke with concentrations of 0 (control), 4.08 $\pm$ 1.32 mg/$m^3$ (low dose), 7.72 $\pm$ 2.14 mg/$m^3$ (medium dose) and 12.83 $\pm$ 1.69 mg/$m^3$ (high dose) total particulate matters (TPM) for 4 weeks. When compared to the control group, the body weights, organ weights in the exposed groups did not show any significant differences. However, certain change of several serum chemical data and biochemical parameters were observed, however, the changes were within normal physiological ranges. Moreover, no changes in organ weight, and no gross/microscopic changes were observed between the exposed and control groups. Salmonella typhimurium reverse mutation, in vivo chromosomal aberration and micronucleus assays revealed that Herbrette did not induce mutagenicity. Upon evaluation of peripheral cellular immunity of mice through in vitro lymphocyte proliferation assay, no significant difference was observed in mean stimulation index between the exposed and control groups. Taken together, our results strongly suggest that Herbrette may not cause toxicity on mice under current condition.