• 한국축산식품학회지
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• 제43권3호
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• pp.402-411
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• 2023

This study was conducted to investigate the bactericidal effect of nisin (Nisin) only, atmospheric pressure plasma (APP) only, and a combination of APP and nisin (APP+Nisin)(APP+Nisin) on beef jerky and sliced ham inoculated with Escherichia coli O157:H7, gram-negative bacteria. The bactericidal effect against E. coli O157:H7 and Listeria monocytogenes was confirmed using a nisin solution at a concentration of 0-100 ppm, and APP+Nisin was tested on beef jerky and sliced ham using 100 ppm nisin. Beef jerky and sliced ham were treated with APP for 5 min and 9 min, respectively. In the bacterial solution, 100 ppm nisin out of 0-100 ppm nisin exhibited the highest bactericidal activity against L. monocytogenes (gram-positive bacteria; p<0.05); however, it did not exhibit bactericidal effects against E. coli O157:H7 (gram-negative bacteria). The APP+Nisin APP+Nisin exhibited a 100% reduction rate in both E. coli O157:H7 and L. monocytogenes compared to the control group, and was more effective than the Nisin. The APP+Nisin decreased the number of colonies formed by 0.80 and 1.96 Log CFU/g for beef jerky and sliced ham, respectively, compared to the control, and exhibited a higher bactericidal effect compared to the Nisin (p<0.05). These results demonstrate the synergistic bactericidal effect of APP and nisin, providing a possible method to improve the limitations of nisin against gram-negative bacteria. In addition, this technology has the potential to be applied to various meats and meat products to control surface microorganisms.

• Journal of Periodontal and Implant Science
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• 제49권5호
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• pp.319-329
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• 2019

Purpose: Direct application of atmospheric-pressure plasma jets (APPJs) has been established as an effective method of microbial decontamination. This study aimed to investigate the bactericidal effect of direct application of an APPJ using helium gas (He-APPJ) on Porphyromonas gingivalis biofilms on sandblasted and acid-etched (SLA) titanium discs. Methods: On the SLA discs covered by P. gingivalis biofilms, an APPJ with helium (He) as a discharge gas was applied at 3 different time intervals (0, 3, and 5 minutes). To evaluate the effect of the plasma itself, the He gas-only group was used as the control group. The bactericidal effect of the He-APPJ was determined by the number of colony-forming units. Bacterial viability was observed by confocal laser scanning microscopy (CLSM), and bacterial morphology was examined by scanning electron microscopy (SEM). Results: As the plasma treatment time increased, the amount of P. gingivalis decreased, and the difference was statistically significant. In the SEM images, compared to the control group, the bacterial biofilm structure on SLA discs treated by the He-APPJ for more than 3 minutes was destroyed. In addition, the CLSM images showed consistent results. Even in sites distant from the area of direct He-APPJ exposure, decontamination effects were observed in both SEM and CLSM images. Conclusions: He-APPJ application was effective in removing P. gingivalis biofilm on SLA titanium discs in an in vitro experiment.

• 식물병연구
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• 제15권2호
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• pp.130-133
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• 2009

Nano-silver 용액의 식물병원성 세균에 대한 항균 활성 검정을 하기 위해 Clavibacter michiganensis subsp. michiganensis를 포함한 10가지 균주를 대상으로 실험을 수행 하였다. Nano-silver용액은 바이오 (주)플러스에서 제공된 WA-CV-WA13B, WA-AT-WB13R과 WA-PR-WB13R용액을 사용하였으며, 10 ppm, 25 ppm, 50 ppm, 100 ppm 농도로 nano-silver 용액을 배지에 첨가하여 nano-silver 배지를 제조한 후 실험대상 세균 균주를 72 h 배양 후 생장억제 정도를 관찰하기 위하여 세균의 colony 수를 세었다. 실험 결과, WA-CV-WA13B 용액의 경우 C-1에 대하여 10 ppm에서도 높은 생장 억제 효과를 나타냈고, P-6, X-1, 그리고 X-2에 대해서도 생장억제 효과를 나타냈고, WA-AT-WB13R용액의 경우 10 ppm의 농도에서 P-6에 대하여 살균효과가 나타났다. 10 ppm의 농도에서는 C-1, X-1, 그리고 X-2에 대해서 약간의 생장억제 효과가 관찰 되었다. WA-PR-WB13R용액의 경우 10 ppm 혹은 그이상의 농도가 P-5, P-6, 그리고 X-2 균주에 대하여 살균효과를 나타내었다. 실험에 사용된 3가지 nano-silver 용액 모두 25 ppm 이상에서 모든 실험대상 식물병원성 세균에 대하여 살균효과를 나타내었으며, 이러한 결과는 nano-silver 용액을 식물병원성 세균의 방제제로 활용할 수 있는 가능성을 보여주는 결과라고 판된다.

• Archives of Plastic Surgery
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• 제34권5호
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• pp.551-556
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• 2007

Purpose: Pseudomonas aeruginosa is an etiologic agent in serious wound infection. Pseudomonas aeruginosa infection is problematic because this organism is resistant to many antimicrobial drugs. The purpose of this study was to compare the bactericidal effect of commonly used topical agents and their effect on wound healing. Methods: Pseudomonas aeruginosa-infected full-thickness skin defect was developed on the mouse to compare 3 commonly used topical agents-Betadine, 2% Gentamicin solution and 0.3% Acetic acid with the control group. Wound size change, bacterial colony counts and histologic findings of each groups were analyzed. Results: The wound size decreased in all treated groups as compared with the control group. However, there was no statistical difference. Gentamicin solution group was showed the lowest bacterial colony count and statistically significant difference compared with the control group(p=0.032). Other treated groups were also effective against Pseudomonas aeruginosa, but not different statistically. Histologic findings revealed that epithelialization, granulation tissue formation and microvessel proliferation were increased and necrosis and inflammation were decreased in all treated groups compared to the control group, but not different statistically. Betadine group significantly increased granulation tissue formation compared to the control group (p= 0.041). Conclusion: There is no universal topical agent that enhances most aspects of wound healing while simultaneously decreasing the bacterial concentration. However, Gentamicin solution may be an optimal topical agent for Pseudomonas aeruginosa infected wound. Further study should experiment on human with Gentamicin solution to confirm a effect on Pseudomonas aeruginosa infected wound for clinical applications.

• 대한치과의료관리학회지
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• 제7권1호
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• pp.50-55
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• 2019

The purpose of this study was to compare the number of bacteria before and after the use of surface disinfectants, demonstrate the bactericidal effect of surface disinfectants, and emphasize on the importance of surface disinfectants by recognizing the importance of infection control in dentistry. Chlorhexidine, hydrogen peroxide, ethanol, and chemical disinfectants are commonly used in dentistry. NaOCl was selected as the experimental group, and the bacterium test results obtained by comparing the table without surface sterilization as a control group showed that all disinfectants had an effective bactericidal effect (p<0.05). In the growth inhibition test comparing the experimental and control groups, all results were 100%, proving the effectiveness of surface disinfectants. The results showed that all surface disinfectants preferred and used by medical institutions were effective. Therefore, all surface disinfectants used in the experimental group were effective for surface disinfection for infection control. Dental clinicians should be aware of the necessity of disinfection of surfaces, such as table, chairs, and unit chairs, and make an active effort to ensure that both clinicians and patients are safe from infection.

• 한국임상수의학회지
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• 제27권3호
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• pp.252-256
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• 2010

소 유방염은 주로 세균 감염에 의한 유선조직에 염증이 생기는 질병으로 유방염의 치료와 억제를 위해서는 1차적으로 세균을 사멸시키는데 있다. 본 연구에서는 소 유방염의 원인이 되는 다양한 세균들에 대한 은 이온의 항균효과와 적용 농도를 측정하였다. 유방염 원인균에 대한 은 이온의 최소 억제 농도 (minimal inhibitory concentrations, MICs)와 최소 살균 농도 (minimum bactericidal concentrations, MBCs)를 측정하였으며, 주사전자현미경 (scanning electron microscopy, SEM)을 이용하여 은 이온에 의한 세균의 형태 변화를 확인하였다. 다양한 유방염 원인균에 대한은 이온의 최소 억제 농도와 최소 살균 농도는 1.9에서 15.6 ${\mu}g$/ml로 세균에 따라 차이가 보였으며, 은이온 처리 후 주사전자현미경 촬영 결과 Staphylococcus aureus와 Escherichia coli의 세포벽이 함몰되거나 파괴되는 것을 볼 수 있었다. 이러한 결과는 유방염 원인이 되는 다양한 원인균에 대해 은이온의 살균 효과와 그 적용 농도를 보여주는 것으로, 소 유방염의 치료와 방어를 위한 임상적인 적용 가능성을 보여주는 것이다.

• 한국미생물·생명공학회지
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• 제50권1호
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• pp.95-101
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• 2022

Due to the pandemic caused by COVID-19, the demand for face masks is soaring and has often caused a shortage. The aim of this study was to evaluate the effect of ultraviolet (UV) and drying treatments on microbial contaminants in facial masks. To conduct this study, standard procedures were designed to develop samples contaminated by the control bacteria Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The contamination level of the standard samples was approximately 6.30 × 10⁶ CFU/ml, and the UV light treatment was performed 1, 3, 5, and 7 times. To evaluate the effect of the UV and drying treatments, the masks were first treated with UV 1, 2, and 3 times, followed by the drying process. As a result, the mask contaminated with E. coli and P. aeruginosa showed a bacterial rate of approximately 99.9% after 1 UV irradiation, and in the case of the S. aureus-contaminated mask, it exhibited a bactericidal rate of approximately 99.9% after 7 UV irradiations. However, when the drying process was included after UV irradiation, all the samples contaminated with E. coli, S. aureus, and P. aeruginosa showed a bactericidal rate of 99.9% or more. The results of this study suggest that UV and drying treatments can effectively reduce the bacterial contaminants in facial masks. In addition, these results provide fundamental data and appropriate sterilization methods for reusing masks.

• 한국수산과학회지
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• 제48권5호
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• pp.661-667
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• 2015

Vibrio harveyi is one of the most serious pathogens causing vibriosis in larval and grow-out shrimp culture. This study was performed to investigate the bactericidal effect of a monopersulfate compound against V. harveyi and its toxicity in Litopenaeus vannamei. The monopersulfate compound was prepared at 0, 0.15, 0.3, 0.6, 1.2, and 2.4 ppm for the bactericidal efficacy study, and then V. harveyi was added at a rate of 1×10⁶ CFU/mL. Subsequently, five shrimps/dose were added to the water bath. The other groups of shrimp were exposed to monopersulfate, but not to the bacterium. None of the shrimps exposed to any of the monopersulfate treatment doses without bacteria died, and no changes in their movement were detected for 7 days. However, shrimps exposed to bacteria without monopersulfate showed decreased movement and lethargy, but no death. The total number of other bacteria and V. harveyi at the different concentrations decreased significantly by 4-6 log values compared to that in the bacterial control group. The monopersulfate compound completely inhibited V. harveyi growth beginning 1 h after exposure to 2.4 ppm. These results show that the monopersulfate compound is an efficient disinfectant against naturally occurring marine bacteria and V. harveyi without being toxic to shrimp.

• 상하수도학회지
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• 제9권3호
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• pp.78-87
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• 1995

A study on the fouling control by periodical ozone-scrubbing was conducted in a membrane filtration process for drinking water treatment. Hydrophilic hollow fiber polyethylene membrane with pore size of $0.1{\mu}m$ and its surface area of $0.42m^2$ was used. Dead-End filtration method was selected to obtain high efficiency of energy. Laboratory prepared synthetic raw water with kaolin was used and the membranes were scrubbed by ozone once in an hour and once in two hours. When the duration of ozone scrubbing was increased from 10 seconds to 20 seconds, the rate of membrane fouling was significantly decreased. Although the frequency of ozone-scrubbing was reduced from once in an hour to once in two hours. the effect of fouling control was unchanged. However, ozone-scrubbing was not effective after a membrane was fouled and washed with detergent for reuse. Among several possible working effects of ozone, bactericidal effect was confirmed to be the primary reason of fouling control.

• 한국식품위생안전성학회지
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• 제28권3호
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• pp.234-240
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• 2013

본 연구는 E. coli와 S. typhimurium을 대상으로 orthophenylphenol 20%를 함유한 훈증소독제, Fumagari OPP$^{(R)}$의 살균효과를 평가하기 위해 수행되었다. 예비 시험에서, E. coli와 S. typhimurium의 현탁액 균수는 모두 $4.0{\times}10^8CFU/mL$이었으며, 모든 훈증소독제에 노출시킨 담체의 균수는 모두 평판배지법과 여과법으로 배양한 시험균주 현탁액의 균수의 50%보다 많았다. 또한, 대조 담체로부터 회복된 E. coli와 S. typhimurium 균수는 모두 $3.4{\times}10^6CFU/mL$이었다. 훈증소독제의 살균효과 시험에서는, 훈증소독제를 처리한 담체의 E. coli와 S. typhimurium의 감소 균수는 각각 5.64와 5.26 logCFU/mL로 나타났다. 이상의 결과로부터, 훈증소독제, Fumagari OPP$^{(R)}$은 E. coli와 S. typhimurium에 대해 효과적인 살균력을 갖는 것으로 확인되었으며, 병원성 세균에 오염된 식품재료 및 주방용품의 소독에 적용할 수 있을 것으로 사료된다.