• Journal of Korean Dental Hygiene Science
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• v.5 no.1
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• pp.21-27
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• 2022

Background: This study was conducted to analyze the time for re-detection of bacteria after surface disinfection using wet wipes, isopropyl alcohol, and benzalkonium chloride antibacterial tissue and provide standards for re-execution of surface disinfection with wet and antibacterial tissues. Methods: Seven laptops were wiped with wet tissue and isopropyl alcohol and benzalkonium chloride antibacterial tissues. Test areas were rubbed with a sterile cotton swab at baseline and after 30, 60, and 120 min. After plating on a tryptic soy agar medium, the number of colonies was counted by culturing at 36.5℃ for 24 h. Results: The average number of bacterial colonies was 5.85 ± 4.33 before isopropyl alcohol wiping and nil after wiping. The average number of bacterial colonies was 12.28 ± 14.67 benzalkonium chloride wiping and nil after wiping. Before wiping with wet wipes, the average number of bacterial colonies on laptop surfaces was 3.42 ± 5.22. Bacteria decreased after wiping with wet wipes but increased again over time. Conclusions: Wet wipes can temporarily reduce bacteria but are unsuitable for removing bacteria.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.4
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• pp.288-292
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• 2006

Through statistically designed experiments, lysis agents were optimized to effectively disrupt bacterial cells in a microfluidic device. Most surfactants caused the efficient lysis of Gram-positive microbes, but not of Gram-negative bacteria. A Plackett-Burman design was used to select the components that increase the efficiency of the lysis of the Gram-negative bacteria Escherichia coli. Using this experimental design, both lysozyme and benzalkonium chloride were shown to significantly increase the cell lysis efficiency, and ATP was extracted in proportion to the lysis efficiency. Benzalkonium chloride affected the cell membrane physically, while lysozyme destroyed the cell wall, and the amount of ATP extracted increased through the synergistic interaction of these two components. The two-factor response-surface design method was used to determine the optimum concentrations of lysozyme and benzalkonium chloride, which were found to be 202 and 99 ppm, respectively. The lysis effect was further verified by microscopic observations in the microchannels. These results indicate that Gram-negative cells can be lysed efficiently in a microfluidic device, thereby allowing the rapid detection of bacterial cells using a bioluminescence-based assay of the released ATP.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.19 no.3
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• pp.207-209
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• 2016

Benzalkonium chloride (BAC) is a caustic agent which is used in farms, homes and hospitals for cleaning skin and wounds as an antiseptic solution. It may lead to digestive system injuries in case of ingestion. We present a two-days-old newborn case which was carried to the emergency unit with complaints of poor breastfeeding, uneasiness and crying for 4-6 hours. Her mom confessed that she had given a spoon of 10% BAC solution for her cough. Initial laboratory tests were in normal ranges. A gastroscopy performed in the second hour of her admission revealed an hyperemic and edematous mucosa in the middle third of esophagus and a circumferential ulceration followed in the distal portion. Hereupon, a conservative treatment for 10 days was administered and the control gastroscopy demonstrated that the damage was almost totally improved. She was the youngest case with this etiology and successfully treated with conservative approach.

• 대한치과보철학회:학술대회논문집
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• 2002.11a
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• pp.84-84
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• 2002

• Journal of the Society of Cosmetic Scientists of Korea
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• v.11 no.1
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• pp.32-52
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• 1985

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2211-2220
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• 2017

Chlorhexidine gluconate (CHX) and benzalkonium chloride (BZK) formulations are frequently used as antiseptics in healthcare and consumer products. Burkholderia cepacia complex (BCC) contamination of pharmaceutical products could be due to the use of contaminated water in the manufacturing process, over-diluted antiseptic solutions in the product, and the use of outdated products, which in turn reduces the antimicrobial activity of CHX and BZK. To establish a "afe use" period following opening containers of CHX and BZK, we measured the antimicrobial effects of CHX ($2-10{\mu}g/ml$) and BZK ($10-50{\mu}g/ml$) at sublethal concentrations on six strains of Burkholderia cenocepacia using chemical and microbiological assays. CHX (2, 4, and $10{\mu}g/ml$) and BZK (10, 20, and $50{\mu}g/ml$) stored for 42 days at $23^{\circ}C$ showed almost the same concentration and toxicity compared with freshly prepared CHX and BZK on B. cenocepacia strains. When $5{\mu}g/ml$ CHX and $20{\mu}g/ml$ BZK were spiked to six B. cenocepacia strains with different inoculum sizes ($10^0-10^5CFU/ml$), their toxic effects were not changed for 28 days. B. cenocepacia strains in diluted CHX and BZK were detectable at concentrations up to $10^2CFU/ml$ after incubation for 28 days at $23^{\circ}C$. Although abiotic and biotic changes in the toxicity of both antiseptics were not observed, our results indicate that B. cenocepacia strains could remain viable in CHX and BZK for 28 days, which in turn, indicates the importance of control measures to monitor BCC contamination in pharmaceutical products.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.608-615
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• 2018

Benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea are commonly used preservatives in cosmetics. Recent reports suggested that these compounds may have cellular and systemic toxicity in high concentration. In addition, diazolidinyl urea and imidazolidinyl urea are known formaldehyde (FA) releasers, raising concerns for these cosmetic preservatives. In this study, we investigated the effects of benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea on ROS-dependent apoptosis of rat neural progenitor cells (NPCs) in vitro. Cells were isolated and cultured from embryonic day 14 rat cortices. Cultured cells were treated with 1-1,000 nM benzalkonium chloride, and $1-50{\mu}M$ diazolidinyl urea or imidazolidinyl urea at various time points to measure the reactive oxygen species (ROS). PI staining, MTT assay, and live-cell imaging were used for cell viability measurements. Western blot was carried out for cleaved caspase-3 and cleaved caspase-8 as apoptotic protein markers. In rat NPCs, ROS production and cleaved caspase-8 expression were increased while the cell viability was decreased in high concentrations of these substances. These results suggest that several cosmetic preservatives at high concentrations can induce neural toxicity in rat brains through ROS induction and apoptosis.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.377-382
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• 2011

This test was performed to evaluate the acute oral toxicity and skin irritation of Lamia-Kill$^{(R)}$, disinfectant, containing 20% benzalkonium chloride and 10% citric acid. In acute oral toxicity, Lamia-Kill$^{(R)}$ was orally administered at dose levels of 2,000, 1,000, 500, 250 and 0 mg/kg body weight. After single oral administration to both sexes of SD rats, the rats were observed for 14 days. In primary skin irritation test, New Zealand white rabbits were dermally treated with Lamia-Kill$^{(R)}$ for 24 hr and observed for 3 days. All rats treated with Lamia-Kill$^{(R)}$ were induced no toxic signs in mortalities, clinical findings, body weights and gross findings. Also, the disinfectant did not induce any adverse reactions such as erythema and edema on intact skin sites for the most part rabbits, but on abraded skin sites, some rabbits showed very slight erythema on 24 hr after topical application. With the results of this study, Lamia-Kill$^{(R)}$ have no effect on acute toxicity and side effect in SD rats and was classified as a practically non-irritating material based on the score 0.50 of primary irritation index.

• Journal of Food Hygiene and Safety
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• v.22 no.2
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• pp.132-136
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• 2007

Disinfectants/sanitizers, showing the bactericidal activity of $5log_{10}$ reduction against E. coli ATCC 10536 and Staphylococcus aureus ATCC 6538 used far assessing disinfectants/sanitizers efficacies, were examined whether showing similar efficacies against Salmonella spp. and Listeria monocytogenes, the major food poisoning bacteria, isolated from foods in current Korean market. The bactericidal efficacies on sodium hypochlorite and benzalkonium chloride were assessed by quantitative suspension tests in both 'clean' and 'dirty' conditions, respectively. Test organisms were consisted of E. coli ATCC 10536, Staphylococcus aureus ATCC 6538, Salmonella typhimurium ATCC 13311, Salmonella Enteritidis ATCC 13076, Listeria monocytogenes ATCC 19111, 10 kinds of Salmonella spp. from foods, and 11 kinds of Listeria monocytogenes from foods. More than $5log_{10}$ reduction in viable count for all strains was only achieved with benzalkonium chloride at the tolerance exemption concentration under dirty conditions. However, all strains were achieved more than $5log_{10}$ reduction under clean conditions.

• Journal of Pharmaceutical Investigation
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• v.27 no.2
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• pp.99-108
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• 1997

To evaluate the feasibility of mucosal delivery of thyrotropin releasing hormone (TRH) through various mucosae, enzymatic degradation and stabilization of TRH in the nasal, rectal and duodenal extracts of rabbits were studied. TRH in the extracts was assayed by HPLC and its degradation was found to follow apparent first-order kinetics. The residual concentrations of TRH in the mucosal extracts of nasal, rectal and duodenal segments after 24 hr of incubation were found to be $65.1({\pm}1.1),\;19.7({\pm}2.7)$ and 0%, and in the serosal extracts, $65.6({\pm}5.5),\;75.2({\pm}1.1)$ and $68.7({\pm}1.4)%$, respectively. This result suggests that there is a significant difference in the activity of TRH-degrading enzymes among the sites of administration. The inhibition of TRH degradation in the mucosa extracts was kinetically investigated using various additives such as thimerosal, benzalkonium chloride, disodium edetate, ${\sigma}-phenanthroline$, dithiothreitol and dithioerythritol, and $IC_{50}$ values of inhibitors were calculated. The results obtained showed that thimerosal (0.5 mM) and benzalkonium chloride (0.141 mM) protected TRH from the enzymatic degradation in all the mucosa extracts more than 95% after 24 hr of incubation.