• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.401-402
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• 2004

• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.115-116
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• 2004

• Journal of fish pathology
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• v.13 no.1
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• pp.45-51
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• 2000

Bacterial diseases with mixed infection have recently occurred at land-based flounder farms in Korea. Thus, single antibacterial is not effective for therapy of mixed bacterial diseases of fish because of their different causative bacteria. The purpose of the present study was to obtain basic data for positive usefulness of a combination of antibacterials used for synergism to mixed bacterial diseases of fish. Snergistic interaction in combination of antibacterials was determined by in vitro antimicrobial activity against selected fish-pathogenic bacteria, Vibrio anguillarum, Edwardsiella tarda, Streptococcus sp., Staphylococcus epidermidis, on the basis of Checkerboard assay using fractional inhibitory concentration (FIC) indices. Synergistic interactions were observed in combinations of (oxytetracycline HCL+lincomycin), (tetracycline HCL+florfenicol), (oxytetracycline HCL+florfenicol) against V. anguillarum, (sodium nifurstyrenate+florfenicol), (tetracycline HCL+florfenicol), (sodium nifurstyrenate+oxolinic acid), (oxytetracycline HCL+florfenicol) against E. tarda, (ciprofloxacine+oleandomycin), (oxytetracycline HCL+oleandomycin), (tetracycline HCL+oleandomycin), (oxytetracycline HCL+lincomycin), (oxytetracycline HCL+spiramycin), (oxytetracycline HCL+erythromycin), (doxycycline HCL+oleandomycin), (tetracycline HCL+spiramycin) against Streptococcus sp., and (ciprofloxacine+erythromycin), (florfenicol+erythromycin), (doxycycline HCL+oleandomycin), (ciprofloxacine+oleandomycin) against S. epidermidis.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.364-373
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• 2015

As an effort to utilize alginate, 103 bacterial isolates that were positive for the alginate lyase activity were isolated from various clams and seawater samples collected in Incheon coastal area. Among them, 3 strains (M1-2-1, M6-1, and C8-15) were finally selected for further analysis based on their activities at higher levels than others. These isolates were all Gram-negative and rod shaped halophilic bacteria with motility. According to their physiological and biochemical properties as well as DNA sequence of their 16S rRNA genes, M1-2-1 and M6-1 were identified as a member of genus Pseudoalteromonas and C8-15 belonged to genus Vibrio. They exhibited the alginate degrading activity at the maximal level when they were cultured in APY broth for 6-8 h at $25^{\circ}C$. Both their growth and the enzyme activity were greatly enhanced when NaCl was added to the growth medium. The crude alginate lyases from the supernatants of the bacterial cultures showed the highest activity at $45^{\circ}C$ and pH 7.0-8.0. M1-2-1 and M6-1 produced 2.723 and 1.976 g/L of reducing sugar from alginate, respectively, suggesting that they have potential for commercial application.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.438-443
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• 2006

Antibacterial effects of six volatile essential oils against Vibrio sp. were evaluated. Volatile components of essential oil were analyzed by gas chromatography and gas chromatography mass spectrometry. Ginger oil treatment inhibited growth of V. parahaemolyticus by 22.5-85.7%. Main volatile compounds of ginger oil were ${\beta}-bisabolene$ (35.19%, peak area) and ${\beta}-sesquiphellandrene$ (12.22%). V. parahaemolyticus was completely inhibited at 1,000 ppm by treatment with mustard oil. Tolerances of V. vulnificus 01 and 02 were twice higher than that of V. parahaemolyticus. Main volatile compound of mustard oil was allyl isothiocyanate (92.55%). Garlic oil treatment of 1,000 ppm inhibited growths of V. parahaemolyticus, V. vulnificus 01, and V. vulnificus 02 by 22.8, 14.6, and 32.9%, respectively. Main volatile compounds of garlic oil were dimethyl sulfide (49.39%) and methyl 2-propenyl disulfide (10.09%). Growth of V. vulnificus 02 was inhibited by 60.6-80.3% via treatment with bud, leaf, and whole oil of clove. Antibacterial activity of whole clove oil on V. vulnificus 02 was stronger than those of ginger, mustard, and garlic oil. Main volatile compounds were eugenol (83.33%) and ${\beta}-caryophyllene$ (7.47%) in clove bud, eugenol (87.46%) and ${\beta}-caryophyllene$ (10.03%) in clove leaf, and eugenol (86.04%) and ${\beta}-caryophyllene$ (9.71%) in whole clove. These results revealed essential oils from spices could be used as potential agents to inhibit Vibrio sp.

• Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.333-339
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• 2015

Red lip mullet Chelon haematocheilus (body weight = $468{\pm}91g$) which became sick during an outbreak of disease at mariculture facilities at Cheonsu Bay, Korea, during July-August 2013, were examined to identify the cause of the disease. Diseased mullets displayed green liver syndrome, and Lactococcus garvieae were isolated from their internal organs. Argulus sp., Trichodina sp., and/or Vibrio spp. were also discovered in some infected fish. Histopathological examination revealed that fatty liver syndrome with hepatocyte degeneration, reflected in heterokaryons, inflammatory lesions, and melanomacrophage centers ($MMC_S$), had caused fibrosis around the kidney, spleen, and blood vessels. After the outbreak, visceral fat and green liver syndrome in the mullets were consistently observed throughout the year in the same mariculture facilities, indicating that the cultured mullets suffered a chronic metabolic disorder. Although Vibrio spp. were also isolated from some individuals, L. garvieae, which is known to be a causative agent of red lip mullet mortality, was isolated from all diseased individuals. This is the first report of L. garvieae infection in cultured red lip mullet.

• Journal of fish pathology
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• v.21 no.1
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• pp.29-34
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• 2008

In this study, we examined in vitro antimicrobial activity of the hydrolysis compound (MBT-01108) of cactus stem (Opuntia ficus-indica var. saboten Makino) against 18 strains of fish pathogenic bacteria, Edwardsiella tarda, Listonella anguillarum, Vibrio sp., Lactococcus garvieae, L. raffinose, Streptococcus parauberis and S. iniae. Antibiotic susceptibility of the same bacteria was also assayed to commercial discs containing various antibacterials. According to these results, MBT-01108 showed the excellent antimicrobial activity against the tested pathogenic bacteria.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.56-61
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• 2003

The purpose of the present study was to screen the effective of lactic acid bacteria (LAB), as probiotics which are able to protect bacterial fish diseases and investigate their characteristics. Twenty strains of lactic acid bacteria were isolated from fish intestine. fermented fish foods and kimchis. These bacteria were screened for antagonistic activity against fish pathogenic bacteria. Seven tested LAB strains were able to inhibit the fish pathogenic bacteria, including Vibrio anguillarum, Edwardsiella tarda and Streptococcus sp. Of the probiotic candidates, BK19 strain which from fermented pollack viscera indicated the largest inhibition activity. This particular probiotic bacteria was identified and named as Lactobacillus sakei BK19. In the scanning electron microscope observation, L. sakei BK19 supernatant treated V.anguillarum cell wall had been destroyed incubate after 3 hr.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.129-134
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• 2003

The purpose of the present study was to screen the effective of lactic acid bacteria (LAB) as probiotics, which are able to protect aquacultural fish pathogenic bacteria, and investigate their characterization. Twenty strains of lactic acid bacteria were isolated from fish intestine, fermented fish foods and kimchis. These bacteria were screened for antagonistic activity against fish pathogenic bacteria. Seven tested LAB strains were able to inhibit the fish pathogenic bacteria, including Vibrio anguillarum, Edwardsiella tarda, and Streptococcus sp.. Of the probiotic candidates, BK19 strain isolated from fermented pollack viscera indicated the largest inhibition activity. Moreover, this strain showed a resistance over low pH and antibiotic agents. Therefore this probiotic candidate BK19 was finally selected and identified as a probiotic strain. This particular probiotic bacteria was identified as Lactobacillus sakei BK19 by biochemical characteristics and 165 rRNA PCR amplification.

• The Journal of the Korean Society for Microbiology
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• v.35 no.3
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• pp.225-237
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• 2000

Vibrio vulnificus, a halophilic vibrio is an estuarine gram-negative bacteria that is associated with severe and frequently fatal wound infections and life-threatening septicemia. Bacteriocins are defined as antibacterial substance produced by various species of bacteria which are usually active against closely related organisms. Bacteriocins have found widespread application in epidemiological studies as specific markers of bacteria. It was proposed by Ha et al. (1990. J. Korean. Soc. Microbiol. 25: 586.) to give the bacteriocins produced by V. vulnificus the name "vulnificins". In the present study, a total of 72 strains of V. vulnificus isolated from patients and oysters were subjected to screen potential producers and indicators of vulnificin, applying ultraviolet induction method. Sensitivity of several strains of Serratia marcesans, Pseudomonas aeruginosa, Shigella flexneri, Salmonella typhi and Yersinia enterocolitica to vulnificins were also examined out. All the tested strains of V. vulnificus produced vulnificins active against indicator strains with various different inhibitory patterns. The spectrum of vulnificin activity and sensitive spectrum of indicator strains were considerably broad. Interestingly, almost all strains of S. marcescens, P. aeruginosa, Salmonella sp., Shigella sp. and Y. enterocolitica tested were sensitive to 1-7 vulnificin(s). Taken together, the present study demonstrated that all of the isolates of V. vulnificus produced vulnificins and that 8 good vulnificin producers and 10 good indicators were detected. These strains can be employed efficiently for establishing vulnificin typing scheme of V. vulnificus and for the detection of bacteriocinogeny and sensitivity in V. vulnificus. Biological role of vulnificin remains to be further elucidated.