• Fisheries and Aquatic Sciences
• /
• v.2 no.2
• /
• pp.167-171
• /
• 1999

This study was designed to develop biomarkers of coastal pollution using biochemical indices of flounder (Paralichthys olivaceus) by changes in lactate dehydrogenase (LDH) activity in the serum and cholinesterase activities in brain membranes. For this purpose acetylcholiesterase (AChE) activity, butyrylcholinesterase (BChE) activity, LDH/AChE ratio and LDH/BChE ratio of cultured flounders at 5 different sites on the southern coast of Korea were compared to those of wild flounders caught in the Pohang, eastern coast of Korea as a control group. Relatively high LDH activities were measured in the serum of flounders cultured on the southern coast of Korea (0.101-0.145 unit) than those in the Pohang control group (0.093 unit). AChE activities were significantly low $(about\;10-20\%)$ in brain membranes of cultured flounders compared to those in the Pohang control group. The ratios of LDH/AChE and LDH/BChE were consistently higher $(136-178\%,\; 155-214\%)$ in cultured flounders than those of Pohang control group. Thus, we propose that the ratios of LDH/AChE and LDH/BChE in flounders could be applicable for the diagnosis of marine pollution.

• Journal of Life Science
• /
• v.7 no.1
• /
• pp.10-16
• /
• 1997

This study was designed as a part of efforts to investigate the biochemical pollutant markers for diagnosis of marine pollutions by changes in oxygen radicals and their scavenger enzymes of the flounder (Paralichthys olivaceus)in Yellow Sea of Kores. Protein contents in brian and muscle of cultured flounder in Yellow Sea were remarkably lower(30-45% and 25-45%, respectively) than those of wild flounders in Pohang(control) of East Sea. Lipid peroxide(LPO) levels in serum of cultured and wild flounders in Yellow Sea were significanltly higher (30-80% and 125-145%, respectively)than those of wild flounder in Pohang. Hydroxide radical formations and superoxide dismutase(SOD) activities in serum of cultured flounders in Yellow Sea were significantly 15-30% and 15-35% lower than those of wild flounders in Pohang, but glutathione peroxidase (GSHPx) activities in brain of cultured flounders in Yellow Sea were significantly 15-25% higher than those of wild flounders in Pohang. It is believed that significantly decreases of protein contents in brain anad muscle, remakable increases of malondialdehyde(LPO) in serum and glutathione peroxidase (GSHPx)in brain of cultured flounders of Yellow Sea may be used as a biochemical pollutant markers for diagnosis of marine pollutions.

• Journal of Life Science
• /
• v.7 no.1
• /
• pp.17-23
• /
• 1997

This study was designed as a part of efforts to investigate the biochemical pollutant markers for diagnosis of maine pollutions by changes in cholinesterase activity of the flounder (Paralichthys olivaceus)in Yellow Sea of Korea. Acetylcholinesterase (AChE) activities in brain and muscle of cultured flounders in Yellow Sea were remarkably lower (40-50% and 40-55%, respectively)than those of wild flounder in Pohang (control) of East Sea, but AChE activities in brain and muscle of wild flounders in Yellow Sea were significantly lower(15-40% and 25-35%, respectively)than those of wild flounder in Pohang of East Sea. Butyrylcholinesterase(BChE) activities in barin and muscle of cultured flounders in Yellow Sea were remarkably lower(70-75% and 65-75%, respectively) than those of wild flounder in Pohang of East Sea, but BChE activities in barin and muscle of wild flounders in Yellow Sea were significantly lower (15-40%and 25-35%, respectively)than those of wild flounder in Pohang of East Sea. Lactate dehydrogenase (LDH) activities in serum of cultured flounders in Yellow Sea were significantly 10-50% higher than those of wild flounder in Pohang of East Sea, but LDH activities in serum of wild flounders in Yellow Sea were significantly 20-25% higher than those of wild flounder in Pohang of East Sea. It suggests that AChE and BChE activities in brain and muscle of cultured and wild flounders of Yellow Sea may be used as the most effective mean in a biochemical markers for diagnosis of pollutant effects by organophosphorus pesticides.

• Korean Journal of Veterinary Service
• /
• v.20 no.1
• /
• pp.11-18
• /
• 1997

Characteristics, pathogenicity and control of the causative organisms isolated front diseased cultured flounder, Paralichthys olivaceus were studied. The causative organisms were identified as E tarda by biochemical and biophysical characteristics. Also, it strains were named as E tarda KBF-1 and E tarda KMF-1, and optimal pH of E tarda KBF-1 and E tarda KMF-1 were 8.0, and optimal concentration of NaCl. E tarda KBF-1 was 0% and E tarda KMF-1 was 1%. In the pathogenicity test, 0~10 of the flounders of artificially infected group(E tarda KBF-1) with $1.0{\times}10^7$ cfu/fish were died within 60 hrs, but 0~9 flounders infected group with 41.0{\times}10^6$ cfu/fish were died within 60 hrs. Also, 0~10 flounders infected group(E tarda KMF-1) with $1.0{\times}10^7$ cfu/fish were died within 36 hrs, while 0~7 flounders infected with $1.0{\times}10^6$ cfu/fish were died within 60 hrs. Drug sensitivity of E tarda KBF-1 strain was resistant to AM, CF and N, and intermediate to E, K and S, and sensitivity to C, G, SxT and FF. But E tarda KMF-1 strain was resistant to CF, E and V, and intermediate to AM, C, N and SxT, and sensitivity to GM and FF.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.48 no.5
• /
• pp.719-724
• /
• 2015

In this study aiming at the cultured olive flounders in Jeju island of Korea, has performed a total of 216 cases of pathogen tests for the olive flounders which seemingly had the symptom of emaciation in 24 farms on the suspicion of its occurrence from June 2010 to December 2013 and intended to get the basic information about the pathogen. According to the survey results of the emaciation infection status of 24 farms in Jeju over the period of this survey, it was confirmed that 18 (75%) of 24 farms in Jeju are positive in the emaciation infection. Among them, as for the rate of infection per year, it was observed that they are 38% in 2010, 48% in 2011, 50% in 2012 and 60% in 2013, and over the period of this survey the infection rate in accordance with the temperature of water has observed a variety of incidence rates from the summer to the winter season. In addition, according to the results of emaciation infection status for each size, the equivalent showed a detection rate, 54% in 11-20 cm, 43.9% in 21-30 cm and 25.4% in over 31 cm. This result accounts for an important portion among the diseases of farmed olive flounders in Jeju, is considered to be one of the diseases which cause troubles in the farms for olive flounders on land and it is thought that it can be utilized as basic data in order to estimate emaciation which may occur in the similar size of the cultured olive flounders in Jeju island.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.53 no.4
• /
• pp.492-498
• /
• 2020

Despite its economic importance, olive flounder Paralichthys olivaceus aquaculture industry is facing a crisis with a continuous production decline. There have been many solutions to overcome the complicate predicament proposed. Increasing genetic diversity and discovering new commercial value through selective breeding are among them. The aims of the present study are to increase the selection power of the golden flounders. We examined the genetic diversity of the breeder population of golden flounders and developed selective markers for the golden flounder population. The 6 microsatellite (MS) markers were selected from melanogenesis-related genes, which are believed to be involved in the pigmentation of fish. All markers were polymorphic (except PO4) and 5 of them had PIC value of 0.6 or above. All makers had distinctive alleles indicating either normal or golden individuals. For examples, from PO4 marker, the frequency of an allele (316) in the golden population was 100% and in normal population was 0% (P<0.001). Although some more studies with more samples at the later generations should be performed to confirm this result, the 316 allele from PO4 marker could be a distinctive tool for decision of the colors in olive flounders at an early stage of the life cycle.

• Korean Journal of Ichthyology
• /
• v.6 no.2
• /
• pp.99-131
• /
• 1994

The taxonomic revision of the flounders of the suborder Pleuronectoidei was made based on the specimens collected from the coasts of the Korean Peninsula from 1989 to 1993. The flounders of Korea are composed 34 species belonging to 24 genera and 4 families, and the keys to species, genera and families are provided with redescriptions and distributions. Three species of the flounders are found to be new to Korea : Tarphops oligolepis (Bleeker) of the family Paralichthyidae, Parabothus kiensis (Tanaka) of the family Bothidae and Pleuronectes pallasii Steindachner of the family Pleuronectidae. Laeops lanceolata, previously recorded in the Korean fish list, was found to be synonym of L. kitaharai. The fishes of the families Paralichthyidae and Bothidae were distributed in the Yellow Sea and the southern coast of Korea, while most of the flounder species of the family Pleuronectidae except Limanda yokohamae, Eopsetta grigorjewi, and Pleuronichthys cornutus were found along the eastern coast of Korea. It appears that Korean flounders are similar to those of Chinese and Japanese faunas which include tropical and temperate species without endemics.

• Korean Journal of Veterinary Research
• /
• v.40 no.2
• /
• pp.333-337
• /
• 2000

This experiment was done to observe the pathological findings of lymphocystis naturally occurred in the cultured flounders in the southern sea of Korea. Anatomical sign of lymphocystis was characterized by the presence of wart-like nodules on the fins, body surface and mouth. Dense clustering of hypertrophic cells originated from fibroblasts was observed in the lesions. Infected hypertrophic cells had a thick hyaline capsule, large vesiculated nucleus with irregular rims and large nucleolus, and large ribbon-shaped basophilic inclusions at the peripheral zone of the cytoplasm. Hexagonal virus particles with the two layers of capsid were scattered throughout the cytoplasm and were absent from the inclusions.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.30 no.4
• /
• pp.608-613
• /
• 1997

This study was designed to investigate the biochemical pollutant marker for diagnosis of marine pollutions by changes in oxygen radicals and their scavenger enzymes of the flounder (Pleuronichthys cornutus) in the Yellow Sea of Korea Protein contents in brain and muscle of wild flounders in the Yellow Sea were remarkably lower $(15\~45\%,\;and\;35\~45\%,\;respectively)$ than those of wild flounder in Pohang (control) of the East Sea. Lipid peroxide (LPO) levels in serum of wild flounders in the Yellow Sea were Significantly higher $(30\~70\%)$ than those of wild flounder in Pohang. Hydroxyl radical formations in serum of wild flounders in the Yellow Sea were significantly high $(15\~90\%)$ than those of wild flounders in Pohang. Superoxide dismutase (SOD) activities in serum of wild flounders in the yellow Sea were significantly lower $(20\~40\%)$ than those of wild flounders in Pohang, and glutathione peroxidase (GSHPx) activities in brain of wild flounders in the Yellow Sea were also significanlty lower $(10\~60\%)$ than those of wild flounders in Pohang. These results suggest that significantly decreases of protein contents in brain and muscle, remarkable in creases of malondialdehyde (LPD) in serum and decreases of SOD and GSHPx activities in serum and brain of wild flounders of the Yellow Sea may be used as a biochemical pollutant markers for diagnosis of marine pollutions.

• Proceedings of the Korea Society of Environmental Toocicology Conference
• /
• 2003.10a
• /
• pp.159-159
• /
• 2003

Comet assay is a potential monitoring tool because DNA strand breakage may be produced by a wide range of agents. The comet assay, also called the single-cell gell electrophoresis (SCGE) assay, is rapid and sensitive method for the detection of DNA damage in cells. This study was performed for the identification of DNA damage in the cells from flounders and clams exposed to PAHs. As a control experiments, flounder and clam cells were exposed to $H_2O$$_2$. The cells exposed to $H_2O$$_2$ were displayed a typical nuclei movement DNA damage of cells were significantly increased when the isolated cells from the blood of flounders and the tissue of clams were in vitro exposed to the different concentrations (5, 10, 50, 100 ppb) of five kinds of PAHs (benzo[a]pyrene, pyrene, fluoranthene, anthrancene, and phenanthrene). For the in vivo test, flounders and clams were exposed to the different concentrations of BaP for 4 days. The results showed that DNA strand breakage was effected by the concentration of BaP and the duration of exposure. In high concentration of BaP, the mean tail lengths of nuclei was longer than it In low concentration, while the mean size of head DNA decreased. In this research, both in vitro and in vivo genotoxicity of PAHs could be biomonitored by the comet assay. Especially, clams and flounders seem to be useful as materials for monitoring genotoxic damage by comet assay.