• Journal of fish pathology
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• v.15 no.3
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• pp.111-115
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• 2002

The scuticocilliate, Uronema marinum is a histophagous ciliate and the causative agent of 'scuticociliatosis'in cultured olive flounder Paralichthys olivaceus. In the present study, in vitro efficacy of hydrogen peroxide, formalin and copper sulfate on the scuticocilliate at low salinity was investigated. Each chemical showed synergistic parasiticidal effects with low salinity (salinity in 5 ppt) compared to each chemical alone (salinity in 33 ppt). At low salinity (5‰), ciliates were killed completely within 1.5h by exposure to 50ppm formalin (37% formaldehyde), at 100ppm hydrogen peroxide (30% solution) and at 100ppm copper sulfate (20% solution). The formalin was the most effective chemical against the parasites at low salinity.

• Ocean and Polar Research
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• v.36 no.1
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• pp.71-76
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• 2014

This study aims to analyze the market interactions among the main farmed fish species in Korea, using both multivariate and bivariate cointegration analysis. For the analysis of market interactions among farmed fish species, major four farmed fish species, olive flounder (Paralichthys olivaceus), black rockfish (Sebastes schlegeli), red seabream (Pagrus major), and grey mullet (Mugil cephalus) were selected as the analytical target species. And their real price data by month from January 2000 to December 2011 were used in the analysis. The results of the multivariate cointegration test for four farmed fish showed that there would be no long-term equilibrium relationships among farmed fish species, and consequently they do not share the same market. The results of bivariate cointegration test indicated that there was little evidence to suggest that all farmed fish species were cointegrated each other. However, it was only analyzed that olive flounder and grey mullet might have a long run equilibrium relationship.

• Applied Biological Chemistry
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• v.15 no.3
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• pp.221-227
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• 1972

(1) A potent lypolytic strain was selected by an extensive screening test of microorganisms isolated from air and various soils on the medium containing olive oil as sole source of carbon. (2) Morphological and physiological characteristics of the selected strain had been investigated, and it has been identified to Trichosporon cutaneum in the manual of LODDER.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.621-623
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• 2017

Mariculture of rainbow trout Onchorhynchus mykiss has been initiated in or around olive flounder Paralichthys olivaceus farms, where viral hemorrhagic septicemia virus (VHSV) is often detected in some fish. In the present study, we investigated VHSV infection in seawater-reared rainbow trout because VHSV has never been detected in salmonids in Korea. A total of 104 adult fish were tested for the presence of VHSV by reverse transcription-polymerase chain reaction, followed by virus isolation with the fathead minnow caudal trunk cell line. Cytopathic effects were observed in two samples but the virus was identified as infectious hematopoietic necrosis virus. Thus, VHSV was not isolated from seawater-reared rainbow trout.

• Fisheries and Aquatic Sciences
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• v.6 no.4
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• pp.225-227
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• 2003

Acetylcholinesterase (AChE) activity is a potential biomarker for phenanthrene exposure in aquatic organisms. Olive flounder (Paralichthys olivaceus) were exposed to three different concentrations (0.5, 1.0 and 2.0, uM) of phenanthrene for four weeks. AChE activities in the brain, heart and eyes were documented. Inhibition of AChE activity was found significant in flounder treated with a concentration greater than $1.0 {\mu}M$ of phenanthrene. This indicates that a chronic exposure to phenanthrene induces damage in various organs (brain, heart and eyes) and changes of AChE activities might be a useful biomarker to assess the impacts induced by polycyclic aromatic hydrocarbon (PAH). Evidence from this study confirms that the measurement of AChE in the brain and eyes of flounder is a valuable tool that along with other biomarkers can maximize an ecotoxicologists' confidence in assessing the impacts of oil and PAH pollution in the aquatic environment.

• Journal of fish pathology
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• v.18 no.2
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• pp.125-131
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• 2005

Amoebic gill disease of flounder, Paralichthys olivaceus was diagnosed at commerical culture facility in South Korea. The amoeba was identified as a species of the genus Neoparamoeba based on the morpholgical characteristics of trophozoites. Transmisson electron microscopy revealed the presence of a symbiotic organism, parasome in the cytoplasm and dense glycocalyx on the surface of the trophozoites. They lacked the boat-shaped microscales on the surface and contained numerous vacuoles and channels, mitochondria in the cytoplasm. Colonization of amoebae on gill tissue elicited extensive fusion and hyperplasia of gill lamella.

• Carbon letters
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• v.6 no.3
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• pp.141-147
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• 2005

The carbon sample "O", phosphoric acid-activated carbon "OP", zinc chloride-activated carbon "OZ", and two steam activated carbons "OS" and "OS2" with different burn-off of 25% and 58% respectively, were prepared from olive stones. The textural properties were determined from the results of nitrogen adsorption at 77 K and by analyzing these results through the application of different adsorption models. The chemistry of the carbon surfaces was determined from the base neutralization capacities, acid neutralization capacity and surface pH. The sorption of $Pb^{2+}$ ions on to the carbons prepared was followed under dynamic and equilibrium conditions. The differences between the values of the textural parameters were attributed to the inapplicability of some adsorption models and to the heterogeneity of the microporous carbons. The sorption of $Pb^{2+}$ ions is favored on carbon and activated carbons. However, chemically activated carbons are more effective compared with steam-activated ones. The sorption of $Pb^{2+}$ ions were related to the chemistry of the surface rather than to the textural properties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.4
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• pp.367-371
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• 2012

To investigate the relationship between metabolic changes in $^1H$-nuclear magnetic resonance (NMR) spectra and fish vaccination, serum was collected from olive flounders treated with a formalin-killed Edwardsiella tarda vaccine and used for $^1H$-NMR metabolite profiling. Principal component analysis and partial least squares were applied to the $^1H$-NMR profile to reduce its complexity and establish class-related clusters. Relative lipid regions were distinguished in vaccinated and non-vaccinated serum. Then, the lipids were extracted from the serum and analyzed. Triolein was identified.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.671-674
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• 2016

We cytogenetically analyzed a triploid King-Nupchi strain of the olive flounder Paralichthys olivaceus to define the simplest, most rapid, and most effective method of ploidy analysis in aquaculture farms. Female triploidy of the flounder King-Nupchi strain was induced by cold shock (3 min post-fertilization at 2-4℃ for 45 min). Triploid induction was confirmed by erythrocyte measurement (nuclear volume, 29.15±2.10 μm³); flow cytometry (2.14±0.03 pg/cell); chromosome count (3N=72); Ag-NOR banding; and silver staining. Silver staining of finned cells obtained using a solid tissue technique was the most effective method of ploidy verification.

• Journal of Microbiology and Biotechnology
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• v.7 no.2
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• pp.151-156
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• 1997

Two commercially available lipases, Lipase OF (non-specific lipase from Candida rugosa) and Lipolase 100T (1, 3-specific lipase from Aspergillus niger), were immobilized on insoluble hydrophobic support HDPE (high density polyethylene) by the physical adsorption method. Hydrolysis performance was enhanced by mixing a non-specific Lipase OF and a 1, 3-specific Lipolase 100T at a 2 : 1 ratio. The results also showed that the immobilized lipase maintained its activity at broader temperature ($25~55^{\circ}C$) and pH (4-8) ranges than soluble lipases. In the presence of organic solvent (isooctane), the immobilized lipase retained most of its activity in upto 12 runs of hydrolysis experiment. However, without organic solvent in the reaction mixture, the immobilized lipase maintained most of its activity even after 20 runs of hydrolysis experiment.