• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.222-227
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• 2001

The members of the genus Vibrio include harmless aquatic strain as well as strains capable of causing infections in human and fish. Pathogenic mechanisms are only understood for Vibrio cholerae O1 and O139 and not for the majority of Vibrio species. Twelve clinical and nonclinical strains were examined by in vitro and in vivo experiments for the importance of extracellular enzymes as a virulence determinant of Vibrio species. In vivo cytotoxicity assay was performed by injecting approximately $10^{8}$ cells/mL into mice (BALB/c). V. harvyi and V. vulnificus showed 100% lethality within 3hr after bacterial injection. V. fluvialis and four strains of V. parahaemolyticus showed 50% lethality within 4hr. V. mimicus, V. alginolyticus and V. furnissii revealed 30% lethality within 9hr. Nonclinical strains, V. campbellii and V. ordalii, did not show any lethality. In vitro protease and hemolytic activities were also good indicators for clinical and nonclinical strains of Vibrio species. The clinical strains showed much higher activities than nonclinical strains. The activity of some clinical strains of re-isolates was evidently increased. Most clinical strains had $\beta$ hemolytic activity. The results demonstrate that the prevalent distribution of extracellular proteases in pathogenic Vibrio sp. implies their importance as a virulence determinant.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.243-244
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• 2001

Vibrio choleae non-O1 has been reported to cause food borne gastroenteritis. This strain produces therm()stable direct hemolysin (NAG-rTDH) similar with that of Vibrio parahaemolyticus. As a result of rabbit ligated intestinal loop test, TDH caused fluid accumulation and is considered to be the major virulent factor. Hemolysis by TDH has been reported to cause colloid osmotic lysis of erythrocytes. (omitted)

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.178-182
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• 2002

The authors identified 68 Vibrio strains from Gwangan beach seawater from June to October in 2001. We identified them as 19 strains of Vibrio alginolyticus, 15 strains of V. vulnificus, 15 strains of V. parahaemolyticus, 11 strains of V. cholerae non O1, 7 strains of V. fluvialis and just one strain of V. hollisae. They showed their typical biochemical characteristics by API 20E kit (bioMerieux), respectively. It was examined whether their cultural supernatants had enzymatic activities such as hemolysin, protease or urease. The 46 strains showed hemolytic activities and/or protease activities. But we could not find any strain which had urease activity. All isolates of V. cholerae non O1 showed $\beta$ hemolysis. The others showed $\alpha$ hemolysis or did not show clear zones on sheep blood agar plates. These results of Kanagawa phenomenon were not always correspondant with hemolytic activities of cultural supernatants at late log phase. Some strains had higher hemolytic activities despite of showing protease activities on skim milk agar plates and in litmus milk media. On the other hand, some strains showed protease activities but did not show hemolytic activities. Therefore we could guess that there were the relationships between hemolysins and proteases produced by pathogenic vibrios.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.2
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• pp.123-125
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• 2007

Vibrio anguillarum is a gram-negative bacterium that causes vibriosis in approximately 80 different fish species. V. anguillarum produces several exotoxins are correlated with the pathogenesis of vibriosis. This study is focused on the composition of the outer membrane vesicle. Most of gram-negative bacteria produce outer membrane vesicle (OMV) during cell growth. OMV was formed from the outer membrane surface of cell and than released to extracellular environment. OMV consists of outer membrane lipids, outer membrane protein (OMP), LPS, and soluble periplasmic components. Also, they contain toxins, adhesions, and immunomodulatory. Many gram-negative bacteria were studied out forming OMV. In Vibrio sp., formation of OMV by electron microscopy has been reported from V. cholerae and V. parahaemolyticus. In present study, we isolated OMV from V. anguillarum and OMV protein was separated by SDS-PAGE. Magor band was sliced and analyzed by MALDI-TOF. The major protein band of 38kDa was identified as OmpU by MALDI-TOF MS analysis.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1473-1480
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• 2016

This study focused on the variations in the non-coding sequences between ctxB and rstR of various CTX phages. The non-coding sequences of CTX-1 and CTX-cla are phage type-specific. The length of the non-coding region of CTX-1 and CTX-cla is 601 and 730 nucleotides, respectively. The non-coding sequence of CTX phage could be divided into three regions. There is a phage type-specific Variable region between two homologous Common regions (Common regions 1 and 2). The non-coding sequence of RS1 element is similar to CTX-1 except that Common region 1 is replaced by a short RS1-specific sequence. The non-coding sequences of CTX-2 and CTX-cla are homologous, indicating the non-coding sequence of CTX-2 is derived from CTX-cla. The non-coding region of CTX-O139 is similar to CTX-cla and CTX-2; however, it contains an extra phage type-specific sequence between Common region 2 and rstR. The variations in the non-coding sequences of CTX phages might be associated with the difference in the replication efficiency and the directionality in the integration into the V. cholerae chromosome.

• Journal of Environmental Science International
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• v.11 no.1
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• pp.33-40
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• 2002

An antimicrobial substance-producing microorganism was isolated from soil samples. Based of the taxonomic characteristics of its morphological, cultural, physiological properties and 16s rRNA sequence alignment, this microorganism was identified as Pseudomonas aeruginosa, and we named Pseudomonas aeruginosa EL-KM. The optimal culture condition for production of antimicrobial substance was 1% mannitol, 0.4% yeast extract, 0.5% Nacl, 0.2% $K_2SO_4$, 100$\mu$M $MgSO_4$.$7H_2O$, 10$\mu$M $CaCl_2$.$2H_2O$, 1$\mu$M $FeSO_4$.$7H_2O$, 1$\mu$M $MnSO_4$.$4-5H_2O$, initial pH 7 and 200 rpm at 3$0^{\circ}C$. The purification of the antimicrbial substance was performed by silica gel column chromatographys, and fraction with TLC $R_f$ 0.77 value represented good antimicrobial activity. The crude antimicrbial substance was stable within a pH range of 3-10 and temperature range of 4$^{\circ}C$-121$^{\circ}C$ autoclaving. This crude antibacterial substance acted as bacteriolytic agent against Vibrio cholerae non-Ol ATCC 25872, and also exhibited excellent properties, when the substance was demonstrated against many other gram-positive, gram-negative bacteria, yeast and fungi.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.114-120
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• 2012

The purpose of this study was to evaluate the antibacterial activities of chopping boards made of various materials such as three antibiotic plastics, a general plastic, and various woods (red pine, rubber tree, cypress, birch, and bamboo) using zone inhibition assay and real-time PCR. Wood chopping boards showed high antimicrobial activity against Vibrio vulnificus, while plastic chopping boards showed high antimicrobial activity against Escherichia coli O157:H7, Salmonella Typhimurium, and Staphylococcus aureus. Bamboo chopping board among the wood chopping boards showed the highest antimicrobial activity against five foodborne bacteria such as E. coli O157:H7, S. Typhimurium, Vibrio cholerae, and V. vulnificus. These results may be helpful in the selection of a chopping board with high antimicrobial activity and in the application of hygiene procedures for prevention of cross-contamination.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.611-616
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• 2001

The bacteriological and physiochemical analysis of seawater in Tongyeong harbor was conducted to evaluate sanitary conditions, The samples were collected at 6 stations established once a month from January to December, 2000. During the study period, the ranges of temperature, transparency, chemical oxygen demand, dissolved oxygen, dissolved nitrogen, phosphate and chlorophyll-a were $6.8\sim25.2^{\circ}C,\;1.0\sim2.5\;m,\;1.79\sim2.41\;mg/L,\;5.7\sim10.1\;mg/L,\;6.59\sim10.53{\mu}g-at/L,\;0.56\sim1.01{\mu}g-at/L\;and\;1.21\sim9.54\;mg/m^3$, respectively, The viable cell counts of seawater in Tongyeong harbor ranged from $3.0\times10^4CFU/mL\;to\;6.9\times10^6CFU/mL$. The coliform group and fecal coliform MPN's of the samples were ranged $23\~4,600\;MPN/100\;mL$ (means 540 MPN/100 mL) and $11\~1,600\;MPN/100\;mL$ (means 210 MPN/100 mL), respectively, The coliform group was classified with IMViC reactions and pathogenic vibrios were analyzed. Two hundred eighteen strains that were obtained from seawater samples in Tongyeong harbor represented Escherichia coli group, $66.1\%$; Citrobacter freundii group, $11.0\%$; Enterobacter aerogenes, $9.6\%$; and unknown, $13.3\%$, respectively. During the study period, infectious bacteria such as Vibrio cholerae O1, Salmonella sp. and Shigella sp. were not detected from the samples, but detection ratios of V. parahaemolyticus, V cholerae non-O1 and V. vulnificus were $10.0\sim30.1\%$.

• Journal of Life Science
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• v.11 no.5
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• pp.483-488
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• 2001

The antimicrobial substance produced by Pseudomonas aeruginosa KLP-2 strain was purified and identified. The substance was identified as a pyocyanine by the fast atom bombardment mass(FAB-MS). In physic-chemical properties, the pyocyanine was dark blue needles, and was soluble in various organic solvents such as chlorogorm, methanol, ethanol and ethyl acetae. The pyocyanine possessed a ultraviolet absorbance spectrum in methanol, 0.1 M HCl, and chlorogorm. The maximum absorption peak of the pyocyanine showed at 318 mm in methanol. The molecular formula of the pyocyanine was determined to the $C_{13}$ H$_{10}$ N$_{2}$O and protonate molecular ion species (M+H)$^{+}$ was observed at m/z 211 by FAB-MS. The pyocyanine showed antimicrobial against Bacillus cereus, Bacillus subtilis, Micrococcus luteus, Rodococcus equi, Staphylococcus aureus, Streptococcus faecalis, E. col, Legionella pneumophila, Shigella flexneri Shigella boydii, shgella sonnei, NAG Vibrio cholerae, Vibrio parahaemolyticus, Vibro vulnificus, Yersinia enterocolitica, and Saccharomyces cerevisiae. However, Salmonella spp. Shigela dysenteriae, 3 strains of Pseudomonas aeruginosa, Klebsiela pneumoniae, and Aspergillus niger were resistant to the pyocyanine. The pyocyanine showed the highest antimicrobial activity aganist Legionella pneumophila based on the size of inhibition zone by the disk contained 0.5 $\mu\textrm{g}$ of the pyocyanine.e.

• Journal of the Korean Society of Food Culture
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• v.15 no.1
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• pp.9-15
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• 2000

This study was conducted to investigate the antimicrobial activity of grapefruit extracts and polylysine mixture against food-borne pathogens. The mixture was showed a potent and quick antibacterial activity for 5 major bacteria causing food poisoning i.e. Escherichia coli, Escherichia coli O-157, Salmonella typhi, Staphylococcus aureus, Vibrio cholerae. The antibacterial effect of the mixture on the ordinary bacteria inhibiting on the surface of lettuce was lasted even 6 hrs after the treatment, however the mixture was non-effective on the color, smell and taste of lettuce. The treatment with 10% mixture solution of the foods such as fish, meat, rice and bread suppressed the growth of the bacteria and kept the foods more freshly than the untreated foods.