• Korean Journal of Clinical Laboratory Science
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• v.52 no.3
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• pp.214-220
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• 2020

Handwashing with soap is an important practice to reduce the transmission of potentially pathogenic microorganisms, but liquid soaps with refillable dispensers are prone to extrinsic bacterial contamination. This study investigated the bacterial contamination of liquid soaps in 58 public restrooms in six buildings. The bacteria were identified by a biochemical test and MALDI-TOF mass spectrophotometry. The antimicrobial susceptibility was determined using the Vitek II system. Of the 58 restrooms examined, 27(46.55%) were using a refill dispenser, of which 25(92.59%) were contaminated with bacteria. The bacteria recovered from the soaps ranged from 1.6×10³ to 2.7×10⁵ CFU/mL. Serratia liquefaciens (12), Achromobacter xylosoxidans (9), S. marcescens (4), Staphylococcus pastueri (1), and Achromobacter spanius (1) were isolated. Except for one A. xylosoxidans, bacteria of the same species isolated in the same building showed a unique resistance pattern. In conclusion, handwashing with contaminated soap may play a role in the transmission of bacteria in public health settings. Therefore, it is necessary to limit the use of refillable liquid soaps in the restrooms of hospitals used by patients with reduced immunity.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.96-104
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• 2013

Staphylococcus aureus is a major human pathogen that produces a wide array of toxins, leading to a number of adverse symptoms. We examined 275 strains of Staphylococcus aureus isolated from various foods between 2006 and 2008 for antimicrobial susceptibility. At least 259 (94.2%) of the tested strains showed antibiotic resistant properties, and 106 (40.7%) of them showed multiple antibiotic resistance. Eleven of the tested strains were resistant to oxacillin and mec A-positive. Moreover, oxacillin-resistant strains were significantly more likely to be multi-drug resistant (p < 0.01). Of the 275 isolates tested, 24.4% were noted as being positive for slime production and 30.5% were positive for biofilm assay. Antibiotic resistance was not associated with a significantly higher prevalence of biofilm formation. Twenty strains were classified using the DiversiLab system. Most of the strains could be classified into 2 clusters and 4 unique types. All 10 mec A-positive strains (cluster I) were grouped together into the same sub-cluster. Cluster II (6 strains) was not found to be resistant to oxacillin in this study. Although the prevalence of methicillin-resistant S. aureus in food is currently low, the risk of its transmission through the food chain cannot be disregarded.

• Journal of Life Science
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• v.16 no.5
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• pp.799-805
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• 2006

The in vitro activities of quinolones were determined with 36 strains of tetracycline- resistant, 39 strains of erythromycin-resistant, 21 strains of both resistant to tetracycline and erythromycin, and 27 strains of both susceptible to tetracycline and erythromycin of the M. pneumoniae isolates which have been isolated and classified in previous studies. The $MIC_{90}$ of moxifloxacin, levofloxacin, sparfloxacin, ofloxacin, ciprofloxacin, amikacin, and clarithromycin against 36 strains of tetracycline-resistant M. pneumoniae isolates were 0.125, 0.39, 0.125, 1.0, 1.0, 15.6, and $1.56\;{\mu}g/ml$, respectively. The $MIC_{90}$ against 39 strains of eryhtromycin-resistant M. pneumoniae isolates were 0.06, 0.39, 0.125, 1.0, 1.0, 15.6, and $25.0\;{\mu}g/ml$, respectively. The $MIC_{90}$ against 21 strains of both resistant to tetracycline and eryhtromycin of M. pneumoniae isolates were 0.125, 0.39, 0.125, 1.0, 1.0, 3.9, and $1.56\;{\mu}g/ml$, respectively. The $MIC_{90}$ against 27 strains of both susceptible to tetracycline and eryhtromycin of M. pneumoniae isolates were 0.125, 0.39, 0.125, 1.0, 1.0, 7.8, and $0.09\;{\mu}g/ml$, respectively. These result suggest that moxifloxacin, levofloxacin, and sparfloxacin of the quinolones might be promising antimicrobial agents for the treatment of tetracycline- and erythromycin-resistant M. pneumoniae infection. However, selection of ofloxacin, ciprofloxacin, and clarithromycin for the treatment of M. pneumoniae infection should be cautious decision with antimycoplasmal susceptibility test.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.4
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• pp.413-419
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• 2017

Four imipenem-resistant bacteria were isolated from the clinical specimens of a patient with pneumonia. To identify the isolates, we used the GN card of Vitek II system and performed a phylogenetic analysis based on 16S rRNA gene sequence. The isolates were identified as P. aeruginosa (2 strains), P. monteilii (1 strain), and P. putida (1 strain), and were tested for antibiotic resistance after determining the MIC of imipenem to be $${\geq_-}8{\mu}g/mL$$ using the AST-N225 card of Vitek II system. The imipenem-resistant genotypes were determined using PCR products amplified using specific ${\beta}-Lactamase$ gene primers. The MBL gene was identified in all four isolates. One strain of P. aeruginosa exhibited the VIM and SHV-1 type genes, while the other strain exhibited both VIM and OXA group II genes. According to the antimicrobial susceptibility test, the bacteria were more susceptible to amikacin than other antibiotics. DNA fingerprint analysis using ERIC-PCR to analyze the epidemiological relationship between strains estimated that both the P. aeruginosa isolates were similar, but exhibited different DNA band types. It is uncommon to find four strains of imipenem-resistant bacteria with different DNA band types in a single patient.

• Journal of Life Science
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• v.24 no.8
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• pp.880-886
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• 2014

In this study, we isolate and identify bacteria from seawater collected from Jeju coast, to evaluate the antimicrobial activity against the fish pathogenic bacteria. 14 bacterial strains were isolated and identified using physiological, biochemical and molecular tools. Antibacterial activity of all the 14 isolates were screened against four major fish pathogens namely, two Gram-positive: Streptococcus iniae, Streptococcus parauberis and two Gram-negative: Vibrio anguillarum, Edwardsiella tarda. Results revealed that among the 14 isolates, MK-11 was found to have antibacterial activity against S. iniae, S. parauberis, V. anguillarum Particularly, S. iniae was susceptibility with the MIC value of $250{\mu}g/ml$. The biochemical and physio-chemical results reveal that MK-11 had the sugar-alcohol disassemble ability of the D-sorbitol and D-mannitol. Also the utilization of the yeast extract, sorbitol and di-potassium phosphate were noted to be high. The optimum culture condition such as pH and temperature was recorded as pH 6.0, $25^{\circ}C$ and along with 1% NaCl which differs from the previous reports particularly in nutrient resolutions. As results of the analysis of 16S rDNA sequences, MK-11 show the high similarity with Paenibacillus polymyxa, P. jamilae, P. brasilensis 99.78%, 99.43%, 99.39%, repectively. Hence, in the present study, the isolated Paemibacillus sp. MK-11 from Jeju seawater possesses the antibacterial activity against fish pathogens and it could be used as a new antibiotic agents against the gram positive fish pathogens.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.683-692
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• 2009

The synthesis of a novel series of nickel(II) complexes with new ligands derived from hydrazones of isoniazid have been reported in present work. The complexes have general compositions [$Ni(L)_2X_2$] or $[Ni(L)_3](ClO_4)_2$ {L = N-isonicotinamido-furfuraldimine (INH-FFL), N-isonicotinamido-3',4',5'-trimethoxybenzaldimine (INH-TMB) or N-isonicotinamido-cinnamalidene (INH-CIN) and X = $Cl^-$, ${NO_3}^-$, $ NCS^-$ or $CH_3COO^-$}. The ligands hydrazones behave as neutral bidentates (N and O donor) through the carbonyl oxygen and azomethine nitrogen. The new complexes with octahedral geometry have been characterized by elemental analysis, molecular weight determinations, magnetic susceptibility/moment, thermogravimetric, electrochemical and spectroscopic studies viz. infrared and electronic spectra. On the basis of conductivity measurements in nitrobenzene ($PhNO_2$) solution the [$Ni(L)_2X_2$] and $[Ni(L)_3](ClO_4)_2$ complexes have been found to be non-electrolytes and 1:2 electrolytes, respectively. Thermal properties have also been investigated, which support the geometry of the complexes. Antibacterial and antifungal properties of nickel(II) complexes and few standard drugs have also been examined and it has been observed that the complexes have moderate antibacterial activities.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.811-815
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• 2007

ln this study we isolated 27 isolates of Campylobacter jejuni from stool samples of 882 diarrheal patients. The seasonal distribution of patients was highest at July (11.7%). All the isolates of C. jejuni hydrolyzing sodium hippurate were serotyped on basis of heat-stable antigens, and identified with the use of passive hemagglutination assay. A total of 59.3% among 27 C. jejuni isolates were identified into 6 different serotypes, which serotype HS2, HSl/44, and HS2l were dominant. Antibiotics resistant rates of C. jejuni isolates were shown to be 100%, 63.0%, 51.9%, 37.0%, 33.3%, 25.9% and 7.4% to cephalothin, trimethoprim- sulfamethoxazole, tetracycline, ciprofloxacin, ampicillin, gentamycin and clindamycin, respectively. All isolates were sensitive to the erythromycin and imipenem.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.305-310
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• 2008

Staphylococcus aureus is one of the most significant pathogens and a causative agents of nosocomial infections. The emergence of methicillin resistant S. aureus (MRSA), in particular, has become a major clinical and epidemiological problems worldwide. In this study, we analyzed the toxin genes and investigated molecular epidemiological characteristics of S. aureus isolated from stools of diarrheal patients at the hospitals in Incheon. Of the 609 strains from 2,281 specimens, 173 strains retained enterotoxin; 68 isolates (39.30%), 100 isolates (57.80%) were classified to A and C type, respectively. In the antibiotic susceptibility, all of enterotoxin positive isolates were resistant to oxacillin. Eighty eight strains (50.86%) of 173 MRSA isolate possessed tsst gene, but eta and eth genes were not detected at all. In the detection of MRSA associated genes by PCR method, mecA genes were detected in 167 strains (96.53%). From the result of PFGE analysis, we classified tsst-positive MRSA to 10 types and 24 subtypes. Type A, H and F were the major strains comprised of 57.95% (51 strains), 10.22% (9 strains) and 9.09% (8 strains) respectively.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.339-345
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• 2008

This study was to detect MBL (metallo-${\beta}$-lactamase) among glucose non-fermenting Gram-negative bacilli isolated from clinical specimen and to search antimicrobial combination therapy against MBL producing Pseudomonas aeruginosa. Among fifty one isolates of Gram-negative bacilli with reduced imipenem susceptibility ($MIC{\ge}8{\mu}g/ml$), nine isolates have shown positive results in MBL detection test. They were seven Achromobacter xylosoxidans subsp. xylosoxidans and two P. aeruginosa. The results from EDTA-DDST coin-cided with those of PCR and nucleotide sequence analysis which showed the presence of $bla_{VIM-2}$. The combination of aztreonam (AZT) and piperacillin-tazobactarn (TZP) or AZT and amikacin (AN) screened by one disk synergy test showed no synergistic effect. Triple antibiotic combination therapy with AZT, TZP and AN, however, was shown to be effective and the most synergistic after 8 hrs of exposure. This result strongly suggest that the triple combination therapy of AZT, TZP, and AN could be useful for the treatment of infection caused by MBL producing Gram-negative bacilli.

• Pediatric Infection and Vaccine
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• v.18 no.2
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• pp.143-153
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• 2011

Purpose : It is known that carriage rates of Staphylococcus aureus (S. aureus) are highest in newborns and that the asymptomatic carriage of methicillin-resistant Staphylococcus aureus (MRSA) is associated with invasive MRSA infection with the colonizing strain. This study was carried out to investigate the carriage rates of MRSA in neonates with neonatal jaundice. Methods : We reviewed the medical records of 545 neonates admitted with neonatal jaundice to neonatal intensive care units between January 2006 and December 2010. Nasal and inguinal swab specimens had been taken from them and cultured for the isolation of S. aureus. Antimicrobial susceptibility tests had been done for such isolates to determine methicillinresistance. Results : Out of 545 neonates, 318 (58.3%) were colonized with S. aureus and 214 (39.3%) were colonized with MRSA. Results of the antibiogram analysis showed that 65.7% of MRSA isolates were likely to be community-associated (CA) MRSA. Conclusion : Based on the MRSA carriage rate of 39.3%, a surveillance program for MRSA colonization is considered necessary in neonates transferred from other clinics or hospitals. Out of MRSA isolates, 65.7% were likely to be CA-MRSA. This suggests that CA-MRSA strains were already present in obstetric clinic environments where the neonates were born. It is thought that MRSA surveillance programs in these environments are also necessary.