• Microbiology and Biotechnology Letters
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• v.51 no.4
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• pp.559-561
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• 2023

Staphylococcus aureus is a ubiquitous pathogen associated with both human and animal diseases. In this study, we present the complete genome sequence of SA73-2, which was isolated from lettuce at an agricultural farm in South Korea. The assembled genome consists of a 2,750,304-bp circular chromosome and a 24,654-bp plasmid. This strain belongs to sequence type 188 (ST188), with spa type 189, and carries the β-lactamase gene (blaZ) on the plasmid.

• Journal of Veterinary Science
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• v.21 no.1
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• pp.2.1-2.14
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• 2020

The emergence of livestock-associated (LA)-methicillin-resistant Staphylococcus aureus (MRSA) in livestock animal has become a significant zoonotic concern. In the present study, we investigated nationwide prevalence of LA-MRSA across pork production chain including pig farms, slaughterhouses, and retail markets. A total of 40 MRSA strains were isolated during the investigation and the overall prevalence of MRSA was 3.4% (n = 37), 0.6% (n = 2), and 0.4% (n = 1) in pig farms, slaughterhouses, and retail markets, respectively. Multilocus sequence typing analyses revealed that the 2 most significant clonal lineages in pork production chain in Korea were ST398 (n = 25) and ST541 (n = 6). All of the 40 MRSA isolates were further characterized to investigate key genotypic and phenotypic correlates associated with the emergence and spread of clonal complex 398 (CC398; ST398, and ST541) LA-MRSA. Although the prevalence of swine-associated MRSA was still relatively low and mostly restricted to pig farms, multidrug-resistant CC398 LA-MRSA isolates with new spa types (t18102 and t18103) were identified as a major clonal lineage. The CC398 LA-MRSA strains tended to exhibit increased levels of multiple drug resistance (MDR) phenotype compared with non-CC398 MRSA strains. Of note, in comparison with non-CC398 MRSA isolates, CC398 LA-MRSA isolates exhibited significantly enhanced tetracycline (TET) and zinc resistance. These findings suggested that co-selection pressure associated with MDR phenotype, especially TET resistance, and zinc resistance may have played a significant role in the emergence and persistence of CC398 LA-MRSA in pig farms in Korea.

• YAKHAK HOEJI
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• v.17 no.3
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• pp.141-146
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• 1973

Eight isatin N-Mannich bases were synthesized and tested their antimicrobial and antitumor activities. N-Piperidinomethylisatin-(N-cyclohexyl)-thiosemicarbazone is active against St. aureus at 10${\mu}$g/disk and isatin thiosemicarbazone against P. chrysogenum at 10${\mu}$g disk.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.13 no.3
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• pp.359-367
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• 2006

Purpose: This study was a within subject repeated pretest-posttest design done to compare the effect of disinfection and the degree of MRSA(Methicillin- resistant staphylococcus aureus) isolation from hand disinfectant in ICU nurses. Method: Out of the total internal medicine/surgery ICU nurses at a university hospital in Seoul, 29 female nurses who were participating in direct patient care were participants in this study. After collection of samples, Staphylococcus aureus and MRSA were isolated from the palms, nails and nasal cavities of the nurses according to disinfectants (soap and beta-scrub). Results: The effect of disinfection was greater in the beta-scrub group than in the soap group, and the effect of disinfection on palms was higher in the beta-scrub group than in the soap group. As for the degree of MRSA isolation, there was more isolation in palms in the soap group than in the beta-scrub group but there was no difference in the degree of MRSA isolation from the hand disinfectant in nails and nasal cavities. Conclusion: Beta-scrub showed a superior prolonged effect against transient bacteria compared with soap. Further, to reduce MRSA infection, we recommend interventions focused on these aspects.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.755-761
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• 1988

The effect of NaCI content levels(1.7, 2.2, 2.7 and 3.2%) on the ripening of a dry sausage was studied, when starter culture and Glucono-delta-Lacton were used. During the ripening of sausages, the physical and chemical properties and the microbial mutiplication were investigated, and also the growth of inoculated Staphylococcus aureus was detected, pH values were slowly decreased and Aw values dropped fastly during ripening period with the increase of NaCl content. In instrumental texture examination, the texture of sausage with NaCl content of 3.2% was significantly harder and more cohesive than those with lower NaCl contents. During ripening St. aureus was decreased by one tenth and not significantly different among mixtures with different NaCl contents. Depending upon reducing NaCl levels, total bacteria and Lactobacilli grew rapidly, while Enterobacteriaceae decreased slowly during ripening.

• KSBB Journal
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• v.10 no.2
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• pp.131-136
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• 1995

0.374(1/day) of specific growth rate and 0.435(mg/108 viable cells) of Anti-Microbial factor (AMF) productivity were obseaved for the batch cultivation of human promyelocytic cells in 10% serum containing medium. The crude protein was purified 10 folds by a serial purification steps of ion exchange chromatography, Bio-Rex 70 and gel filtration chromatography, Sephadex G-70 and 100. The ranges of MIC(Minimal Inhibitory Concentration) of commercially available antibiotics, penicillin G, streptomycin and ampicillin was estimated as 40 to ($70\mu\textrm{g}$/ml) on Gram (-) E. coli and Gram (＋) Streptococcus aureus. The values of the MBC (Minimal Bactericidal Concentration) of Purified AMF was ($0.5\mu\textrm{g}$/ml) and 0.4($\mu\textrm{g}$/ml), respectively. The molecular weight of the AMF was estimated as 15,000 dalton by SDS-PAGE.

• Pediatric Infection and Vaccine
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• v.26 no.3
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• pp.148-160
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• 2019

Purpose: This study aimed to investigate the molecular epidemiology of a methicillin-resistant Staphylococcus aureus (MRSA) outbreak at a newborn nursery and neonatal intensive care unit (NICU). Methods: During the outbreak, from August to September 2017, MRSA isolates collected from neonates and medical staff underwent genotyping and screened for virulence factors. Antibiotic susceptibilities were tested. Results: During the study period, 41 neonates were admitted at the nursery (n=27) and NICU (n=14). Of these, 7 had MRSA infections (skin infection [n=6] and sepsis [n=1]) and 4 were colonized with MRSA. Associated medical staff (n=32) were screened; three were nasal MRSA carriers. Staphylococcal chromosomal cassette mec (SCCmec) type II, sequence type (ST) 89, spa type t375 was found to be the skin infection outbreak causing strain, with multi-drug resistance including low-level mupirocin resistance. SCCmec type IVa, ST 72, and a novel spa type designated t17879, was the cause of MRSA sepsis. Many different types of MRSA were colonized on the neonates; however, SCCmec type IVa, ST 72, spa type t664 was colonized in both neonates and a NICU nurse. All MRSA isolates from colonized infants were positive for the Panton-Valentine leukocidin (PVL) toxin gene. Conclusions: The strain causing an outbreak of skin infections had multi-drug resistance. Also, MRSA colonized in the neonates were found to carry the PVL toxin gene. Because different strains are present during an outbreak, molecular epidemiologic studies are important to identify the outbreak strain and colonized strains which aid in effective control and prevention of future MRSA outbreaks.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.43-50
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• 2011

Hibiscus cannabinus L. is a plant in the Malvaceae family, that was seeded at June 1st in 2010 and harvested at November 18th. The present study was designated to investigate the safety for host cells, antibacterial effects of Hibiscus cannabinus L. of flower (HCME-F) or leaf (HMEF-L) methanol extract for typical Gram's positive bacteria (St. aureus and Str. epidermidis) or Gram's negative bacteria (S. typhimurium and E. coli). In treatment of different concentrations of HCME-F or HMEF-L (1, 50 and $100{\mu}g/ml$), cytotoxic effects were not shown to RAW 264.7 cells until 24 h incubation. In determination of antibacterial activity of HCME-F or HMEF-L, the antibacterial activities for St. aureus and Str. epidermidis were markedly increased compared to that of untreated control group, but antibacterial activity of HCME-F or HMEF-L for S. typhimurium and E. coli were not changed. Taken together, we demonstrated that methanol extract of HCME-F or HMEF-L showed the safety for RAW 264.7 cells and antibacterial activities for Gram's positive pathogenic bacteria St. aureus and Str. epidermidis. These findings suggest that a methanol extract of Kenaf flower or leaf may be useful alternatives of conventional chemotherapies for dermatitis and mastitis causing Gram's positive pathogens such as Stapylococcus spp. and Streptococcus spp. in domestic animals and humans.

• Biomedical Science Letters
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• v.11 no.4
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• pp.447-453
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• 2005

A total of 108 strains of MRSA (Methicillin-resistant Staphylococcus aureus) clinical isolates was collected from $121^{st}$ general hospital (U.S. military hospital), Korean healthcare facility from January to March in 2005 and Wonju Christian hospital in 1999. Antimicrobial susceptibility test by Vitek System and MIC test using oxacillin and cephalothin stripes by E-test were executed. PCR based detection of mecA gene was performed on the all of MRSA clinical isolates, too. MRSA clinical isolates were characterized with antimicrobial resistance patterns, PCR based detection of mecA gene and validation of the multiplex PCR strategy of SCCmec among clinical isolates.

• Journal of Food Hygiene and Safety
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• v.10 no.4
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• pp.271-277
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• 1995

Total 29 Monascus strains were isolated from Ang-Khak and 4 of them were selecte based on the relative intensity of soluble red pigment and growth rate. The optimum growth temperature of the selected isolates was 32.5$^{\circ}C$ on malt extract agar(MEZ) plate. The optimum growth pH was 5.0 on czapek yeast extract agar plate, while it was pH 6.2 or 6.5 on MEA plate. Isolate No. 116, especially, showed the strongest animicrobial activity aganist Bacillus subtilis and Staphylococcus aureus but much less aganist Escherichia coli and Enterobacter aerogenes. The maximun antimicrobial activity of isolate No. 116 against St. aureus was achieved at initial pH 5.3 on rice extract broth. The acitivity was increased with increasing amount of culture broth concentrate of isolate No. 116.