• Journal of Korean Ophthalmic Optics Society
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• v.10 no.1
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• pp.63-69
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• 2005

The effects of R products of B company and natural disinfectant naringin, well-known chemical disinfectant on Corneal endothelium and epithelium of rabbit were observed by scanning electron microscope. The main component of naringin is extract of grapefruit seed, which is one of the flavonoid widely recognized as natural antioxidants and used as preservative agent of food and cosmetics. The chemical disinfectants cytotoxicity in cell cultures were announced by MIT assay and LDH leakage assay. But there has been no study about that chemical disinfectants and natural disinfectants is inserted drops on rabbit's cornea directly. In this test R products B company and natural disinfectants has been dropped on the cornea of rabbits for one weeks and observed cytotoxiciy by light camera after rose bengal staining. Also, we analysed the damage of corneal epithelium and endothelium morphologically after enucleating the cornea by scanning electron microscope.

• Applied Microscopy
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• v.35 no.3
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• pp.129-134
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• 2005

The cytotoxicity that chemical disinfectants of K products and natural disinfectants of naringin & chitosan well-known preservative, have on endothelium and epithelium of rabbit's cornea were obseved by scanning electron microscope. The main component of naringin is grapefruit seed extract, which is one of the flavonoid widely recognized as natural antioxidants and used as preserved food and cosmetics. The chitosan also wildly distributed epithelium of crustacea, epidermis of insects, mould, fungi and so on. It is no harm of cytotoxicity of human body and recognized of antibacterial for various of bacteria. This study was performed to examine the cytotoxicity of natural and chemical preservative.

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.2
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• pp.65-69
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• 2003

The effects of grapefruit seed extract and $H_2O_2$ disinfectants on Pseudomonas aeruginosa were investigated by antimicrobial assay and scanning electron microscopy. Pseudomonas aeruginosa is a Gram negative bacteria and a common causative microorganism of bacterial keratitis. After incubation of soft contact lens in Pseudomonas aeruginosa suspension for 120 minutes containing the disinfectants, the grapefruit seed extract showed antimicrobial activity as good as the chemical disinfectant. The living rates of Pseudomonas aeruginosa in grapefruit seed extract and $H_2O_2$ disinfectants were $1{\times10^3CFU/m{\ell}$ and $0.5{\times}10^3CFU/m{\ell}$, respectively showing no major difference in the killing activity. However, the mechanisms of the antimicrobial activity were quite different as indicated by scanning electron microscopy of the bacterial surface morphology. Considering chemically or other toxins induced keratitis, the natural disinfectant isolated from grapefruit seed extract shows promising results as a soft contact lens disinfectant.

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.117-122
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• 2014

Rice can be the contaminating with soil-borne bacteria. Furthermore, the contaminated bacteria can be grown during immersion process for produce wet-milled rice flour. Therefore, disinfectants can be added during the immersion process. Antibacterial activities of the natural disinfectant, fermented rice spent water (FRSW), and the chemical disinfectants, chlorine dioxide (CD) and sodium benzoate (SB), were respectively determined when added in pure cultures of target bacteria such as Salmonella typhimurium, Escherichia coli, and Bacillus cereus or when added to immersion water in the immersion process. In addition, rinsing effects for removing bacteria were determined when rice was rinsed with water before and after the immersion process. Antibacterial activities were rapidly increased as increasing amounts of the disinfectants are added to the pure cultures of the target bacteria. Antibacterial activity of CD was the most effective among the three tested disinfectants when added to the pure cultures of the target bacteria, respectively. Those of the same disinfectants were increased when they were increasingly added to the immersion water. However those of the disinfectants were less effective when added to the immersion water. On the other hand, rinsing effects for removing bacteria were the most effective when rice was rinsed only with water without the immersion process. Collectively, rinsing rice with water only was more effective than using disinfectants in the immersion water during rice flour production.

• The Journal of Natural Sciences
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• v.10 no.1
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• pp.17-21
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• 1998

Numerous chemicals were tasted to show antiviral activity in vitro against tobacco mosaic virus (TMV). With a brief exposure of TMV to 1 N HCl or 1-0.1 N NaOH, Virions and their encapsidated RNAs were degraded completely and rapidly. When TMV was exposed to 0.1 N HCl, the hydrolysis of viral capsid in 5 min after treatment was observed in the 1% agarose gel. Virions and their encapsidated RNAs were not degraded by 0.01N HCl of 0.01N NaOH. These characteristics indicate that a short exposure to optimal concentration of acid or base is of practical value in eliminating infectious virus. The treatment of 50% isopropanol or UV light did not damage in viral integrity or their encapsidated RNAs. Disinfection of the agricultural tools and laboratory equipments using appropriate disinfectants is necessary to prevent cross contamination if farm and laboratory.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.230-234
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• 2003

The Bacillus subtilis YvaE protein, the small multidrug resistance (SMR) family (TC #2.A. 7.1), is shown to catalyze efflux of multiple cationic drugs including many disinfectants, when it was cloned and expressed in Escherichia coli. When the yvaD gene was coexpressed with yvaE gene, the yvaD protein, encoded within a single operon with the yvaE gene, is shown to counteract the action ofYvaE. By ethidium efflux analysis, the cells harvoring a vector with yvaE gene showed a rapid ethidium efflux, compared with the control cells. These results clearly suggest that YvaE mediates drug export from the cell cytoplasm.

• Applied Microscopy
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• v.19 no.2
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• pp.17-26
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• 1989

The cells of Campylobacter jejuni treated with physical or chemical disinfection agents were comparatively examined by scanning and transmission electron microscopies for their morphological features and internal ultrastructures. The normal cells of C. jejuni, showed typical spiral rod shapes. The ribosomes, nucleoids, and other cellular constituents were observed to be distributed evenly throughout the cytoplasm. The cells treated with heat or UV-light were changed to spherical or irregular shapes and their cell envelopes were destroyed to form ghost cells by liberating their cytoplasmic components. The cells treated with chlorine or monochloramine were also changed into irregular round shapes. The chlorinated cells showed very rough surface structures with many blob-like protrusions, while the surface of the monochloramine-treated cells appeared to be relatively smooth.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.63-71
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• 1979

Tests were made to find new non-mercurious seed disinfectants that were best for rice seeds. For these experiments four seed samples carr)?ing natural infection of Pyricularia oryzae, Helminthosporium oryzae, and Fusarium moniliforme were used and the following fungicides were used; Zinc Omadine, Sodium Omadine, Panoctine, Tecto-F, Benlate-T, Homai, Sisthane, $P_{242}$, Busan 30, Tecto-Wp and Terracoat Zn. Blotter method and water agar plate method used in the laboratory and growing-on test used in greenhouse. Results have shown that Sisthane, $P_{242}$ and Sodium Omadine have equal or superior effect to organic mercury compound against P. oryzae, H. oryzae, and F. moniliforme. Benlate T and Homai are effective against blast and Bakanae disease, but are inferior to organic mercury compound against brown spot disease. Busan 30 and Panoctine are effective against blast and brown spot disease, but have moderately inferior effects against F. monilifome. It is considered that the recommendable testing methods of seed treatment were blotter method for P. oryzae and water agar plate method for H, oryzae and F. moniliforme according to the experimental results obtained. No phytotoxicity against seed germination and seedling growth were observed when treated with disinfectants before germination of seeds.

• Journal of Environmental Health Sciences
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• v.45 no.4
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• pp.340-357
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• 2019

The purpose of this paper is to help develop a comprehensive understanding of the humidifier disinfectant disaster from diverse perspectives based on a critical review of the relevant academic research papers published so far in the fields of both natural and social science. The authors reviewed pertinent articles in the six academic areas of law, social science, humanities, medicine, toxicology, and environmental health. A proper understanding of the issue of humidifier disinfectant is a challenging task because diverse aspects of it have become related over the more than two decades since such products were first released to the market in 1994. Technical and esoteric issues such as the complex system for relief and compensation for health damages and the approval of chemical toxicity are known to be major impediments to viewing the bigger picture regarding this tragedy. The authors believe that experts need to consider a comprehensive perspective going beyond their individual research arena to gain a better understanding of this issue, especially since it was an alarm signal on ethics and the role of experts and scholars in Korean society. Besides the two professors arrested by the prosecutor's office, it should be remembered that medical doctors recommended patients use humidifiers and disinfectants, and the media was inactive in reporting on this issue. Furthermore, the current paucity of examination of the social and political implications of this tragedy calls for more active engagement by researchers in the humanities and social sciences. In this regard, this paper is a work of self-examination and self-criticism by the authors that could resonate with the overall academic community.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.173-180
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• 2004

This study aims to investigate the effects of hydrogen peroxide and grapefruit seed extract used as a chemical and natural disinfectants on human conjunctival cells in vitro. The main component of grapefruit seed extract is a narigin. It is one of the flavonoid types in citrus fruits and f1avonoids are widely recognized as naturally occurring(삭제) antioxidants. Cytotoxicity was determined by mitochondrial activity(MTT assay) and DNA damage was analyzed by measuring Comet assay. In LDH assay, 5% of grapefruits seed extract has been observed as a material is giving recovery effect of damaged cultured conjuctival cells by hydrogen peroxide. And also, each of concentrations has been treated simultaneously with same amounts and cytotoxicity of hydrogen peroxide and grapefruit seed extract have been estimated by LDH leakage assay after 24 hours. In conclusion, H2O2-induced cytotoxicity, apoptosis were Significantly prevented by grapefruit seed extract. It is a main component of bioflavonoids that we can simply take it as food. The present results suggest that grapefruit seed extract is a useful disinfectanct having antioxidant and antiapoptopic activity as a natural product.