• Advances in materials Research
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• v.4 no.4
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• pp.207-214
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• 2015

It has been reported in the technical literature that orotic acid can be used in order to induce improved crystallization of biodegradable and biocompatible polymers like poly(L-lactic acid), polyhydroxybutyrate and poly(hydroxybutyrate-co-hydroxyhexaonat). The expected advantage of the changed crystalline structure is a reinforcing effect of the polymers. A lot of papers reported about the application of inorganic and organic agents for acceleration of heterogeneous nucleation. This study reports on an attempt to use orotic acid as appropriate non-toxic nucleating agent for improving mechanical properties of isotactic polypropylene. Special attention is given to demonstrate the effect of nucleation in a typical melt spinning process in order to improve the mechanical properties. The effects were demonstrated using rheology, thermal analysis and tensile testing.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.411-416
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• 2018

Chlorpyrifos (CPF) is one of the most heavily used organophosphate pesticides and is useful as an insecticide drug. However, CPF also causes toxic effects in nontarget organisms, including humans and animals. Jageum-Jung (JGJ) is a traditional oriental medicine, composed of five specific herbs with antioxidant and hepatoprotective properties, used for detoxification. In the present study, highly concentrated CPF was orally administrated to male Institute of Cancer Research mice to produce acute toxicity, and the protective effects of JGJ administration were investigated through statistical analysis of changes in body and organ weights and serum biochemical parameters. JGJ caused body and organ weights to recover and reduced the levels of serum biochemical parameters indicative of liver damage, such as glutamic oxalate transaminase, glutamic pyruvate transaminase, alkaline phosphatase, lactic dehydrogenase, urea, glucose, total cholesterol, and triglyceride, that had been increased by CPF treatment. Our results demonstrated that JGJ ameliorates the effects of acute chlorpyrifos-induced toxicity. Therefore, JGJ has the potential to be used as a traditional medicine to alleviate insecticide toxicity.

• Journal of Environmental Health Sciences
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• v.37 no.2
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• pp.113-123
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• 2011

Objectives: Industrial development in Korea results in a rapid increase in the number of chemicals, some of which may be responsible for toxicity to aquatic ecosystems. In addition, the types of hazardous chemicals included in industrial effluents have gradually increased. Therefore, chemical analysis alone is not enough to assess ecological effects of toxic chemicals in wastewater. Methods: In response to new regulations as whole effluent toxicity (WET) tests for effluent discharge of 15 publicly owned treatment works (POTWs) and 25 industrial effluent treatment plants in Gyeonggi-do, which will be effective from 2011, a necessity of studies emerges that investigates toxicity levels. Results: In case of the public treatment plants, none of them had exceeded the criteria for ecotoxicity. As for individual wastewater discharge facilities, on the other hand, two types were found to exceed the criteria: pulp and paper manufacturing facilities and pharmaceutical manufacturing facilities. For the pulp and paper manufacturing facilities, monitoring results could not help determine the exact toxicant identification. However, Daphnia magna inhibition effect or death was found to leave white plums, suggesting that suspended solids treated and the polymer used in coagulant dose. In case of pharmaceutical manufacturing facilities, the general water quality parameters cannot affect Daphia magna. However, conductivity and salinity can have an effect to be 14,000 ${\mu}s/cm$, 8.1‰ by salts, respectively. Toxicity Identification Evaluation (TIE) and Toxicity Reduction Evaluation (TRE) procedures results appeared to be effective for identifying toxic compounds in $Cl^{-}$ and $SO_4^{2-}$. Conclusions: It is necessary to develop control measures for water treatment chemicals and salts used for processes such as coagulation in individual wastewater discharge facilities in order to achieve the goal to protect aquatic ecosystems in public waters.

• Animal Bioscience
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• v.34 no.9
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• pp.1479-1490
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• 2021

Objective: Our recent findings confirmed the effectiveness of sodium metabisulfite (SMB) in controlling the growth of undesirable microorganisms in fruit and vegetable discards (FVD); however, lactic acid bacteria (LAB) are susceptible to its antibacterial effects. Two series of experiments were conducted to enable the survivability of LAB during silage fermentation of a total mixed ration (TMR) containing SMB-treated FVD. Methods: In Exp. 1, the objective was to isolate a strain of LAB tolerable to the toxic effect of SMB. In Exp. 2, the SMB load was minimized through its partial replacement with a chemical mixture (CM) based on sodium benzoate (57%), potassium sorbate (29%), and sodium nitrite (14%). FVD was treated with SMB + CM (2 g each/kg biomass) and added to the TMR at varying levels (0%, 10%, or 20%), with or without KU18 inoculation. Results: The KU18 was screened as a presumptive LAB strain showing superior tolerance to SMB in broth medium, and was identified at the molecular level using 16S rRNA gene sequence analysis as Lactobacillus plantarum. Inoculation of KU18 in TMR containing SMB was not successful for the LAB development, biomass acidification, and organoleptic properties of the resultant silage. In Exp. 2, based on the effectiveness and economic considerations, an equal proportion of SMB and CM (2 g each/kg FVD) was selected as the optimal loads for the subsequent silage fermentation experiment. Slight differences were determined in LAB development, biomass acidification, and sensorial characteristics among the experimental silages, suggesting the low toxicity of the preservatives on LAB growth. Conclusion: Although KU18 strain was not able to efficiently develop in silage mass containing SMB-treated FVD, the partial substitution of SMB load with the CM effectively alleviated the toxic effect of SMB and allowed LAB development during the fermentation of SMB + CM-treated FVD in TMR.

• Journal of Microbiology
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• v.44 no.2
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• pp.200-205
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• 2006

The tributyltin (TBT)-resistant bacterium, Pseudomonas aeruginosa 25W, which was isolated in seawater from the Arabian Sea, was subjected to transcriptome analysis in the presence of high concentrations of TBT. Only slight effects were observed at TBT concentration of $50{\mu}M$, but exposure to $500{\mu}M$ resulted in the upregulation of 6 genes and the downregulation of 75. Among the 75 downregulated genes, 53% (40 out of 75) were of hypothetical function, followed by 14 transcriptional regulation- and translation-associated genes. The results of this study indicated that although the 25W strain was highly resistant to TBT, high concentrations of TBT result in toxic effect on the transcriptional and translational levels. The target genes likely belong to a specific category of transcription- and translation-associated genes rather than to other gene categories.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.29-40
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• 2004

Because cleaning products are part of our everyday lives, it is essential that they should not present significant risks to health. However, many petrochemicals in most soaps and detergents can be absorbed through the scalp and skin and, over time, accumulate in the organs and tissues. This accumulation may result in brain, nerve, and liver damage. Therefore, it is interested in developing non-harmful detergent. According to Korea Research Institute of Chemical Technology, GC-100X may be non-harmful and non-corrosive alkaline ionic water (pH 12). It is composed of hydroxyl radicals and supplemented with xylitol. To evaluate influence of GC-100X on rats and beagles, GC-100X was diluted with distilled water (25%, 50%, and 100% solution respectively). Each of diluted GC-100X was daily treated per oral. In body weight analysis, urinary analysis, ophthalmological test and autopsy, we did not find any significance, but in serum biochemical analysis and hematological analysis, we found some significances in middle dose group compared with control group. These significances in serum biochemical analysis and hematological analysis may be not induced by GC-100X, because it was not found to be significant from control group in histopathological examination. Thus, it is concluded that NOEL(No Observed Effect Level) of GC-100X may be higher than all treatment doses used in this study, and GC-100X may be a non-toxic detergent.

• Journal of fish pathology
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• v.36 no.2
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• pp.415-422
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• 2023

In veterinary medicine for mammals, studies are being conducted to confirm the effects of antioxidants using pathological toxicity model studies, and are also used to confirm the effect of mitigating liver or kidney toxicity of specific substances. It was considered necessary to study such a toxicity model for domestic farmed fish, so thioacetamide (TAA), a toxic substance that causes tissue damage by mitochondrial dysfunction, was injected into rainbow trout (Oncorhynchus mykiss), a major farmed freshwater fish species in Korea. The experiment was conducted with 40 rainbow trout (Oncorhynchus mykiss) weighting 53 ± 0.6 g divided into two groups. Thioacetamide(TAA) 300mg/kg of body weight was intraperitoneally injected into rainbow trout and samples were taken 1, 3, 5, 7 days after peritoneal injection. As a result, in serum biochemical analysis, AST levels related to liver function decreased 3 and 5 days after intraperitoneal injection and increased after 7 days, and ALT levels also increased after 7 days. In addition, creatinine related to renal malfunction increased 3 and 5 days after TAA injection. In histopathological analysis, pericholangitis and local lymphocyte infiltration were observed in the liver from 1 day after intraperitoneal injection of TAA, and hepatic parenchymal cell necrosis was also observed from 3 days after intraperitoneal injection. Hyaline droplet in renal tubular epithelial cell was observed from 1 day after TAA injection, and acute tubular damage such as tubular epithelial cell necrosis appeared from 3 days after TAA injection. Accordingly, it is thought that it will be able to contribute to studies that require a toxicity model.

• Journal of the Korean Society of Safety
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• v.34 no.6
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• pp.13-21
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• 2019

Leakage accidents in businesses dealing with hazardous chemicals can have a great impact on the workers inside the workplace, as well as residents outside the workplace. In fact, there were cases where hazardous chemicals leaked from many businesses. As a result, the Chemicals Control Act(CCA) was enacted in 2015, the Ministry of Environment introduced an Off-site Risk Assessment(ORA). The purpose of the ORA is to secure safety from the installation of the design of the workplace facilities so that chemical accidents of hazardous chemical handling facilities do not cause human or physical damage outside the workplace. In general, the ORA qualitatively determines where a protected facility is within the scope of the accident scenario. However, elderly who belong to the sensitive group is more sensitive than the general group under the same chemical accident effect, and the extent of the damage is serious. According to data from the Korea National Statistic Office, the number of elderly people is expected to increase steadily. Therefore, a quantitative risk analysis considering the elderly is necessary as a result of a chemical accident. In this study, accident scenarios for 14 locations were set up to perform emergency evacuation due to toxic gas leakage of Cl₂(Chlorine) and HF(Hydrogen Fluoride), and the effects of exposure were analyzed based on the evacuation velocity difference of age 20s and 60s. The ALOHA(Areal Locations of Hazardous Atmospheres) program was used to calculate the concentration for assessing the effects. The time of exposure to toxic gas was calculated based on the time it took for the evacuation to run from the start point to the desired point and a methodology was devised that could be applied to the risk calculation. As a result of the study, the relative risk of the elderly, the sensitive group, needs to be determined.

• Biomolecules & Therapeutics
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• v.7 no.2
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• pp.158-163
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• 1999

In order to find less toxic antiherpetic agents, antiviral activities of quercitrin against two strains of pathogenic viruses such as herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) were determined in Vero cells using plaque reduction assay in vitro. Quercitrin showed a concentration-dependent decrease in plaque formation of HSV-1 and HSV-2. It also exhibited more potent antiherpetic activity on HSV-1 with 50% effective concentration (EC$_{50}$) of 20.4 $\mu$g/ml than on HSV-2 with EC$_{50}$ of 30.4 $\mu$g/ml. The combined antiherpetic effects of quercitrin with nucleoside antiherpetic agents, acyclovir and vidarabine, were examined on the multiplication of these two strains of herpesviruses in Vero cells by the combination assay. The results of combination assay were evaluated by the combination index (CI) that was calculated by the multiple drug effect analysis. The combinations of quercitrin with acyclovir and vidarabine on HSV-1 showed more potent synergism with CI values of 0.27-0.81 for 50%, 70%, 90% effective levels than those on HSV-2 with CI values of 1.03~2.20..20.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.77-84
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• 1999

To search for less toxic antiherpetic agents, the inhibitory effects of natural naringenin on the plaque formation of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in Vero cells were examined by the plaque reduction assay in vitro. Naringenin inhibited plaque formations of HSV-l and HSV-2 in a dose dependent manner. It also exhibited more potent antiherpetic activity on HSV-l with selectivity index (SI) of 19.1 than on HSV-2 with SI of 5.7 The combined antiherpetic effects of naringenin with nucleoside antiherpetic agents, acyclovir and vidarabine, were examined on the multiplication of these two strains of herpesviruses in Vero cells by the combination assay. The results of combination assay were evaluated by the combination index (CI) that was calculated by the multiple drug effect analysis. The combinations of naringenin with acyclovir on HSV-l and HSV-2 showed more potent synergism with CI values of 0.28∼0.81 for 50%, 70%, 90% effective levels than those with vidarabine with CI values of 0.86-3.28.