• Journal of Veterinary Clinics
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• v.17 no.1
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• pp.145-151
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• 2000

황색포도상구균이 Capsular polysaccharide (CPS)는 백혈구의 탐식에 저항하기 때문에 젖소의 유방염 발생의 중요한 병원상 인자로 오랫동안 연구자들의 관심이 집중되어 왔다. 따라서 CPS는 젖소의 유방염을 최소화시키기 위한 유방염 백신개발에 있어 잠재적인 백신 항원물질로 알려져 왔다. 본 연구의 복적은 황색포도상구균의 CPS 항원물질을 좀더 효과적으로 발현시키고 향후 백신항원으로 사용시 좀 더 간편하게 정제하는 방법을 찾아보고자 본 연구를 수행하였다. CPS는 락토스와 덱스트로스를 첨가한 brain heart infusion media 에서도 부분적으로 발현되었지만 CPS가 가장 잘 발현되는 배지 조건은 젖소 유래의 유청을 10% 첨가한 조건에서 가장 발현율이 높았다. 또한 CPS발현은 salt agglutination test, india ink법 및 투과전자현미경을 이용하여 확인하였으며 균체표면의 hydrophobicity에서는 락토스, 덱스트로스 및 젖소 유래의 유청을 첨가한 배지조건에서 다른 조건에 비해 높았다. CPS의 가장 손쉬운 검사법은 균체를 절편하지 않고 직접 투과전자현미경상에서 염색없이 관찰하는 것이 가장 간편한 방법이었다. CPS정제는 상층액을 농축시킨후 이온교환크로마토그라피와 젤 여과법을 이용하여 정제하였으며 CPS의 분자량은 대부분 97kDa이상이었다. CPS 회수율은 배지와 균체 1리터당 1.5mg이었다. 결론적으로 CPS를 백신항원으로 포함하고자 할 경우, CPS의 최적 발현조건은 젖소 유래의 유청을 10% 첨가한 Brain heart infusion 배지에서 배양하여 사용하는 것이 가장 좋은 방법이라고 생각된다.

• Journal of Veterinary Clinics
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• v.28 no.4
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• pp.446-448
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• 2011

A 1-year-old, male, captive born Burmese Python (Python molurus bivittatus) presented with cloudiness of the left eye after ecdysis. Based on physical examination and history, subspectacular abscess was diagnosed. The causative microorganism was identified as a methicillin-resistant Staphylococcus aureus (MRSA). MRSA is a zoonotic problem of high concern and is a risk in public health and veterinary medicine. To our limited knowledge, this is the first reported case of MRSA infection in snakes.

• Journal of Life Science
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• v.20 no.4
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• pp.589-596
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• 2010

We investigated antimicrobial activities of various pine (Pinus densiflora) needle extracts against antibiotic resistant strains of Staphylococcus aureus. Hot water extract showed the highest antimicrobial activity against normal and methicillin resistant Staphylococcus aureus (MRSA), however, it exhibited no antimicrobial activity against penicillin resistant S. aureus (PRSA). Hot water-hexane (HWH), hot water-ethanol (HWE), hexane, and ethanol extracts showed antimicrobial activity against S. aureus, PRSA and MRSA. Minimum inhibitory concentrations (MIC) of HWH, HWE, hexane, and ethanol extracts were 0.05, 0.05, 0.5 and 5 mg/ml, respectively, and HWH and HWE extracts showed the strongest antimicrobial activity among these extracts. Antimicrobial activities of pine needle extracts were stable after heating at $121^{\circ}C$ for 20 min. These results suggested that pine needle extracts can be used as an effective natural antimicrobial agent for food and medical industries.

• Journal of Food Hygiene and Safety
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• v.28 no.1
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• pp.36-40
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• 2013

This study was performed to determine the ranking foods and related foodborne pathogens for the impact of climate change, e.g., increasing temperature, on microbiological food safety. To do this, we developed an impact-ranking model comprising an Excel spreadsheet by using Risk Ranger. Because of a lack of data, input values in this model were determined on the basis of an expert's opinion. These values also were converted to normal distribution, and the developed model was simulated using @RISK. In conclusion, the 5 superior ranking foods and related foodborne pathogens for climate change impact were as follows: ready-to-eat foods (RTE) (Staphylococcus aureus, Salmonella spp., and Escherichia coli O157:H7); bread and rice cakes (S. aureus and Bacillus cereus); meat and egg products (Salmonella spp., E. coli O157:H7, and S. aureus); tofu (bean curds) and jellies (B. cereus, E. coli O157:H7, and S. aureus); and fish products (S. aureus, Vibrio spp., and E. coli O157:H7).

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.106-114
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• 2019

The effect of physical and chemical treatments to reduce staphylococcal phages was investigated. To determine impact of physical treatment on viability of phages, two staphylococcal phages (SAP84 and SAP89) were treated with multiple heat ($55^{\circ}C$ and $60^{\circ}C$) and pH (pH4, 7, 10) conditions. Viability of SAP 84 was dramatically reduced at 60C and SAP 89 was completely inactivated at 60C within 25 min. Overall, the two phages were stable under all the pH conditions tested except for the SAP 89 at pH 10. Treatments, a 10% FAS (Ferrous Ammonium Sulfate) solution and various density of ethanol and sodium hypochlorite were used to reduce the two phages. SAP 84 was unstable in 50% and 70% ethanol. However, SAP 84 and SAP 89 showed high tolerance after exposure to 100 ppm of sodium hypochlorite which is known as an effective sterilizer. As soon as the two phages were treated with 10% FAS, which is used as a virucidal agent, they were inactivated and did not form any plaque. The result of this study provides additional evidence that staphylococcal phages can be controlled by various physicochemical treatments.

• Applied Chemistry for Engineering
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• v.35 no.3
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• pp.248-254
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• 2024

In this study, functional substances with antibacterial properties were extracted from the needles of Abies holophylla and Pinus koraiensis, and optimized using the central composite design-response surface methodology (CCD-RSM). The optimal extraction conditions for Abies holophylla were an extraction temperature of 59.5 ℃ and an ethanol/ultrapure water volume ratio of 69.5 vol.%, resulting in an extraction yield of 13.5% and inhibition diameters of 11.6 mm against Escherichia coli (E. coli) and 9.3 mm against Staphylococcus aureus (S. aureus). For Pinus koraiensis, the optimal extraction conditions were an extraction temperature of 59.2 ℃ and an ethanol/ultrapure water volume ratio of 67.8 vol.%, resulting in an extraction yield of 4.8% and inhibition diameters of 7.9 mm against E. coli and 12.5 mm against S. aureus. The actual experimental results under these optimal conditions showed that an extraction yield from Abies holophylla needles was 13.0% and an inhibition diameter of 11.7 mm against E. coli and 9.2 mm against S. aureus, indicating an error rate of approximately ± 2.3%. For Pinus koraiensis needles, the extraction yield was 5.1%, with inhibition diameters of 7.5 mm against E. coli and 12.3 mm against S. aureus, indicating an error rate of ± 4.23%.

• Clinical and Experimental Pediatrics
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• v.48 no.11
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• pp.1193-1200
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• 2005

Purpose : Invasive bacterial infection is a major cause of morbidity and mortality in children. Previously, we reported etiology of invasive infections in healthy children in 1985-1995. This study was performed to update etiology of invasive bacterial infections in the previously healthy children. Methods : We reviewed medical records of 98 episodes of invasive bacterial infections in immunocompetent children at the Seoul National University Children's Hospital in 1996-2004. Results : The frequent pathogens identified over all age groups were Streptococcus pneumoniae (33%) and Staphylococcus aureus(33%). The proportion of Salmonella species and Haemophilus influenzae has been declined to 4% each from 23% and 14%, respectively, compared to previous study. S. agalactiae was the most common isolate in the infants ${\leq}3$ months. Among the infants and children aged 3 months to 2 years and children of 2-5 years, S. pneumoniae(57%, 52%, respectively, in each group) was the most common isolates followed by S. aureus(17% and 24%, respectively). S. aureus was the most common isolates(73%) in children >5 years. Primary bacteremia was the most common clinical diagnosis(27%). S. pneumoniae was responsible for 42% of primary bacteremia, 50% of meningitis, and 69% of bacteremic pneumonia and empyema. S. aureus accounted for 80% of bone and joint infections. The case fatality rate was 8.1% for all invasive infections. Conclusion : We reviewed frequency of bacterial agents of invasive infections in children. The data may be useful for pediatricians to select adequate empirical antibiotics in the management of invasive bacterial infections.

• Journal of the korean veterinary medical association
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• v.43 no.10
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• pp.918-928
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• 2007

• Journal of the korean veterinary medical association
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• v.43 no.11
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• pp.1027-1038
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• 2007

• Journal of the korean veterinary medical association
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• v.43 no.12
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• pp.1119-1132
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• 2007