• Journal of Veterinary Clinics
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• v.16 no.1
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• pp.26-30
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• 1999

본 연구는 임상형 및 준임상형 유방염에 이환된 젖소의 유즙에서 분리된 24주의 황색포도상구균에 대한 capsular polysaccharide(CP)형을 확인하고, 1% 토끼 혈청이 함유된 serum-soft agar 배지에서 집락의 모양을 관찰하였다. 또한 동물에 따라 우세한 CP형의 차이가 있는지를 비교하고자 개에서 분리된 13주에 대하여 동일한 실험을 수행하여 다음과 같은 결과를 얻었다. 집락모양을 관찰한 결과 젖소 유래 24주 중 16주(66.7%)는 diffuse, 5주(20.8%)는 compact, 나머지 3주(12.5%)는 분류가 불가능(indeterminate)하였다. CP형 확인결과 9주(37.5%)는 type 5, 2주(8.3%)는 type 8, 13주(54.2%)는 분류가 불가능(non-typeable)하였다. 한편, 개에서 분리된 균주 중 1주(type 8)를 제외한 12주(92.3%)는 type 5로 분류되었으며, 13주 중 8주(61.5%)가 diffuse형의 집락을 보였다. 본 실험에 사용한 균주의 수가 충분하지 못한 문제가 있지만 동물에 따라 우세한 CP형이 다를 수 있으며 분류 불가능한 균주가 상대적으로 높은 비율을 차지하였는데 이는 새로운 CP형의 분류형이 필요함을 시사하는 것으로 판단된다. 또한 type 5와 type 8만을 포함한 유방염 백신은 한계가 있을 것으로 사료된다.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.19 no.2
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• pp.161-167
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• 2006

독활(Aralia continentalis)로부터 항균활성 물질을 찾아내기 위한 일환으로 항균실험과 분리실험을 병행하여 실시하였다. 항균활성물질 분리는 독활을 클로로포롬으로 추출하여 실리카겔($SiO_2$)과 분취용액체크로마토그래피(prep-HPLC)법으로 2종의 화합물을 분리하여 핵자기공명(NMR) 등 분광학적인 기법으로 이용하여 구조동정을 하였다. 이때 2종의 화합물은 (-)-pimara-8(1),15-diene-19-oic acid와 (24E)-stagmasta-5,22-dien-$3{\beta}-ol$임이 확인되었다. 2종의 화합물에 대한 메티실린 내성 황색포도상구균(MRSA) 및 메터실린 감응 황색포도상구균(MSSA)의 표준균주와 임상분리균주(MRSA)에서의 최소억제농도(MIC)가 $8-16{\mu}g/mL$로 나타났다. 그러므로 본 연구의 결과로부터 화합물(-)pimara-8(1),15-diene-19-oic acid은 항생제 내성균에 대한 치료제로서 개발 가능성을 확인할 수 있었다.

• Journal of radiological science and technology
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• v.45 no.2
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• pp.165-170
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• 2022

Staphylococcus aureus is a major pathogen that causes clinical infections in humans and can also cause massively colonized in lesion skin, particularly in atopic dermatitis patients. This study investigated the effects of photodynamic inactivation with radachlorin and diode laser irradiation on the viability of S. aureus in vitro and assessed the effects of the dose of laser transmission. In the PDI group, 5 𝜇L of S. aureus suspension and 5 𝜇L of radachlorin were inoculated in a 55 mm petri dish (63.6 cm²). The samples were placed in a 37° incubator for 30 min and then irradiated with light (660 nm diode laser). After laser irradiation, the cells were stored for 24 h at 37° in an incubator with 5% CO2, and the number of colonies was counted. All CFU/mL of S. aureus were reduced by diode laser in the presence of radachlorin, with a killing rate of 87.9% at an energy dose of 9 J/cm². This study contribute to treat colonized with S. aureus in atopic dermatitis patients and wound infections by providing information on the optimal dose of laser transmission using PDI to eliminate S. aureus.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.339-345
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• 2019

The present study aims to investigate the potential applications of Aristotelia chilensis (A. chilensis) extracts as novel cosmetic materials. The total extracts of A. chilensis were partitioned into chloroform (CHCl₃), ethyl acetate (EtOAc), and distilled water (DW) fractions. A. chilensis extracts exhibited no cytotoxicity toward HaCaT human keratinocyte and B16F10 mouse melanoma cell lines. CHCl₃, EtOAc, and DW extracts reduced oxidative stress, and EtOAc extract was superior to glutathione, a natural human antioxidant positive control. The extracts of A. chilensis reduced melanin synthesis in cells treated with α-melanocyte-stimulating hormone. The extracts of A. chilensis exhibited antibacterial effects toward Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and Pseudomonas aeruginosa (P. aeruginosa). In particular, the EtOAc extract was effective in terms of antibacterial activity against S. aureus. In the present study, we identified several potential applications of A. chilensis extracts in terms of novel antioxidant and whitening cosmetic materials as well as antibacterial preservatives.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.206-210
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• 2017

This study was performed to develope mathematical models for predicting growth kinetics of Staphylococcus aureus in the processed meat product, pyeonyuk. Growth patterns of S. aureus in pyeonyuk were determined at the storage temperatures of 4, 10, 20, and $37^{\circ}C$ respectively. The number of S. aureus in pyeonyuk increased at all the storage temperatures. The maximum specific growth rate (${\mu}_{max}$) and lag phase duration (LPD) values were calculated by Baranyi model. The ${\mu}_{max}$ values went up, while the LPD values decreased as the storage temperature increased from $4^{\circ}C$ to $37^{\circ}C$. Square root model and polynomial model were used to develop the secondary models for ${\mu}_{max}$ and LPD, respectively. Root Mean Square Error (RMSE) was used to evaluate the developed model and the fitness was determind to be 0.42. Therefore the developed predictive model was useful to predict the growth of S. aureus in pyeonyuk and it will help to prevent food-born disease by expanding for microbial sanitary management guide.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.166-172
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• 2015

This study was performed to develop treatment method for reducing microbial contamination on Daruma (a semi-processed product of seasoned and dried squid) by combination of strong acidic hypochlorous water (SAHW) and ultrasonic waves (UW). The available chlorine concentration, oxidation reduction potential (ORP) and pH of SAHW were $69.67{\pm}0.58ppm$, $1071.33{\pm}4.16mV$ and 2.79, respectively. The 1.49 log CFU/g of viable cell count and 1.32 log CFU/g of Staphylococcus aureus was reduced, and Escherichia coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of sodium hypochlorite solution (SHS) for 120 min. The 3.62 log CFU/g of viable cell count and 3.22 log CFU/g of Staphylococcus aureus was reduced, and Escherichia coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 120 min. The antibacterial effects of SAHW were stronger than those of SHS at same available chroline concentration. SAHW treatment after washing strongly alkalic electrolyzed water (SAEW) showed better bactericidal effects than SAHW treatment only. The 4.0 log CFU/g of viable cell count was reduced, S. aureus was reduced below regulation limit (Log 2.0 CFU/g), and E. coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 90 min after washing with 20 times (w/v) of SAEW for 60 min. The viable cell number was reduced below detection limit and S. aureus was reduced below regulation limit when the Daruma was treated with 20 times (w/v) of SAHW for 60 min in ultrasonic washer. E. coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 10 min in ultrasonic washer. These results suggest that combination of SAHW and UW may be a good technique to reduce the microbial contamination in daruma.

• Microbiology and Biotechnology Letters
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• v.39 no.1
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• pp.77-85
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• 2011

The antibacterial activities of silver nanoparticles (Ag-NPs) were studied with respect to Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli by observing the bacterial cells treated or not with Ag-NPs by FE-SEM as well as measuring the growth curves, formation of bactericidal ROS, protein leakage, and lactate dehydrogenase activity involved in the respiratory chain. Bacterial cells were treated with Ag-NPs powder, and the growth rates were investigated under varying concentrations of Ag-NPs, incubation times, incubation temperatures, and pHs. As a result, S. aureus and E. coli were shown to be substantially inhibited by Ag-NPs, and the antibacterial activity of Ag-NPs did not fluctuate with temperature or pH. These results suggest that Ag-NPs could be used as an effective antibacterial material.

• Journal of Life Science
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• v.18 no.8
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• pp.1083-1089
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• 2008

We investigated the molecular epidemiological characteristic of methicillin resistant Staphylococcus aureus (MRSA) strains isolated from stool samples in Busan from 2004 to 2006. Among 142 isolates of S. aureus, 49 isolates (34.5%) were confirmed as MRSA. With the antimicrobial susceptibility tests, 37 isolates (75.5%) showed multiple resistance to more than 10 antibiotics, but all isolates were sensitive to vancomycin. All of MRSA had enterotoxin A in 30.6%, B 4.1%, C 8.3%, D, C/G, A 2.0% and None 51%. PFGE of SmaI-digested chromosomal DNA was performed on 49 sporadic MRSA isolates. Restriction fragment patterns consisted of 8 to 14 fragments ranged in size from 48.5 to 630.5 kbp. We could divided the isolates into 7 groups ($I{\sim}VII$) by analyzing PFGE patterns. Group I subdivided as 2 subgroups and 17 (34.7%) strains belong to the group I. Dendrogram of PFGE patterns showed that MRSA strains in Busan were heterogeneous but we could find out minor homogeneity in hospital.

• Journal of Food Hygiene and Safety
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• v.17 no.1
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• pp.31-35
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• 2002

According to food poisoning statistic data of 2000, the food poisoning outbreaks have occurred mainly by meat (27.9%), shellfish and its processed products (26.0%), and ready-to eat meals (24.0%) such as Kimbap and packed lunch boxes. The major causative flood poisoning bacteria were Salmonella spp. (35.6%), Staphylococcus aureus(11.3%) and Vibrio parahaemolyticus (3.2%). In this study, we conducted the isolation and enumeration for S. aureus in Kimbap. This monitoring data will be applied to the following study, risk assessment. The Kimbap samples were collected from department stores, convenient stores and snack bars located in Seoul, Busan, Daejeon, and Gwangju. The overall isolation rate of S. aureus from 214 Kimbap samples was 34.1% and the average count was 623 cells. Enterotoxin typing test for isolates showed 42.5%, 4.1% and 2.7% for type, A, B and C, respectively. There was no significant seasonal difference in S. aureus isolation, but the average count in summer(793 cfu/g) was 1.8 times higher than that of winter(446 cfu/g).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.372-378
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• 2019

Traditional ceramic glazes formulated with copper oxide (CuO) exhibited antibacterial properties on Staphylococcus aureus (Gram Positive) and Escherichia coli (Gram Negative). All the ceramic glazes containing CuO showed antibacterial behavior when fired in reducing atmosphere. However, some of copper glazes presented antibacterial behavior and had no antibacterial properties at all when sintered in an oxidizing atmosphere. To elucidate the antibacterial mechanism, ceramic glazes were studied for phase and microstructure analysis, dissolution behavior and surface zeta potential. Metallic copper was precipitated in the glaze layer when sintered in reducing atmosphere. Less than 0.05 ppm of Cu ion was dissolved from glazes. Ca ion was most dissolved among all the samples. Glaze surface was highly negatively charged when CuO was added over 3 wt.% regardless of the sintering atmosphere. The antibacterial behavior of ceramic glazes seemed to be directly related to the dissolution behavior of cations, but the antibacterial behavior of oxidized specimens was not explained by the dissolution behavior. Surface potential of ceramic glazes appeared to play an auxiliary role in antibacterial properties.