• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.103-109
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• 2000

Complete senuences of the mitochondrial rRNA Benes were determined among six salmonines in Korean Waters (Brachpmystax lenok, Onoorhpchus keta, O. masou mason, O. mason ishikawae, O. mykiss, and albino mutant of O. mykiss). The purposes of this study were to provide the basic information on levels of mtDNA polymorphism among these species for genetic characterization; discuss phylogentic relationships among three Oncorhynchus sepecies; demonstrate the utility of rRNA gene sequence data as a genetic marker for disringuishinf among Korean salmonines. PCR/direct sequencing data indicated the following consistent results; 1) 12S rRNA genes was 945 bases long in Oncorhynchus species, and 946 bases in B. lenot including one insertion. 2) Of sequence variation in mitochondrial rRNA regions, transitional substitutions were superior to transversion. 3) The significant differences were not shown in the intraspecific variation values in these gene regions. The percentage sequence divergence values were ranged from $0.066 to 0.212{\%}$. 4) The interspecific divergences were greater than the intraspecific variation. Nevertheless, ribosomal RMh genes were more conserved among species than the other mitochondrial genes, and they showed potentiality as an intergenic marker for systematics. In addition, phylogenetic trees, constructed from this data, supported that cherry salmon was closer to chum salmon than to rainbow trout, and that lenok was most distantly related species in six salmonid species.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.902-907
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• 2000

Protamine-strong basic protein was prepared from salmon(chum salmon, Oncorhynchus keta) sperm by several pretreatment method. And there were determined yield, amino acid composition, antimicrobial and antioxidant activity of protamine on each pretreatment condition. The yield of protamine was different according to pretreatment, and ultrasonicating, homogenizing and microwaving pretreatment were about 16.0%, 15.5% and 10%, respectively. The main amino acid of P60(microwaving pretreatment for 10 min at $80^{\circ}C$) and UU6(ultrasonicating pretreatment for 60 min at $20^{\circ}C$) were arginine, proline and tryptophan, and arginine content of P60 and UU6 were 61%, 53%, respectively. On the other hand, main amino acid of M(homogenizing pretreatment by mixer) were methionine, proline and arginine, the content were 34%, 28% and 11%, respectively. Also MC(homogenizing pretreatment with $H_{2}SO_{4}$ soln. by mixer) was very different with P60, UU6 and M, the content of MC were proline 44.8% and arginine 39.7%. Prepared protamines showed antimicrobial activity to several gram(+) and gram(-) strain. In particular, the UU6 and P60 protamine has strong antimicrobial activity to Bacillus subtilis and Escherichia coli, and the activity was increased with concentration increasing. Regardless of pretreatment method, all protamine showed antioxidant activity and the $EDA_{50}$ of P60, UU6, M and MC were $101\;{\mu}g/mL$, $410\;{\mu}g/mL$, $523\;{\mu}g/mL$ and $490\;{\mu}g/mL$, respectively.

• Journal of Life Science
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• v.28 no.3
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• pp.284-292
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• 2018

The melanin-concentrating hormone (MCH), a cyclic hypothalamic peptide composed of 17 amino acids, was initially identified in chum salmon (Oncorhynchus keta) as a regulator of pigmentation. Mammalian MCHs are cyclic hypothalamic peptides composed of 19 amino acids that regulate food intake and energy homeostasis. The present study examined not only MCH expression of different tissues but also the melanohore aggregation and intracellular $Ca^{2+}$ influx of fMCH and the other MCH. Real-time qPCR showed that MCH expressed specially in the brain, gonad, and ovary, and expression of MCH was observed during the developmental stages. In the application of synthetic fMCH and both types of synthetic fMCH, dN-fMCH and dC-fMCH, scale melanophore induced significant changes in aggregation activity with various concentrations of MCH. Also, compared to hMCH and sMCH, fMCH exhibited a 36~99.85% increase in relative potency (%), whereas aggregation of dN-fMCH and dC-fMCH remained in a high concentration. However, dispersion was induced rapidly according to be low concentration of dN-fMCH and dC-fMCH. We show that fMCH and its derivates were bound human MCHR1 and rat MCHR expressed in HEK293T cells with nano-molar affinity and are likely to be ligand-induced to mobilize intracellular $Ca^{2+}$. These results may provide new ligands for binding assay with MCHew ligands, as a structure similar to the mammalian MCH structure was discovered in fish. Once the fMCH receptor system is in place, it can be compared to the MCH system of mammals in terms of MCH function.

• Journal of fish pathology
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• v.20 no.2
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• pp.147-160
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• 2007

Four strains of water mold, ChS-E0511, RaT-E0511, RaT-A0512 and MaS-F0512, were isolated from salmonid fish and/or their eggs taken from culture farms in Yangyang, Milyang and Pyeongchang, Korea in 2005. Descriptions of their morphological aspects, the results of the phylogenetic analysis conducted, and the sequence of the small sub-unit 18S rRNAs of the isolates confirmed that they all belong to the species Saprolegnia parasitica. Only one species, ChS-E0511, which was isolated from fertilized eggs of the chum salmon, was classified as part of the S. parasiticaGroup 1 according to its oogonia and gemmae production. The chemotherapeutic effects of various chemicals on the ChS-E0511 strain were assessed from the inhibitory effects of growth in GY media and the relative ratio of eyed eggs to fertilized eggs of the rainbow trout. Malchite green, a prohibited substance in food animals, was better than others, such as the Opuntia ficus-indicaextract, 2-bronopol, and sodium chloride. These results suggest that the fungi isolated from salmonids and/or their eggs identified as S. parasitica were composed of more than two groups. These isolates will be useful in an intensive evaluation of therapeutic agents.

• Journal of fish pathology
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• v.11 no.2
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• pp.129-136
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• 1998

In March 1997, a new rhabdovirus was isolated from moribund cultured Japanese flounder Paralichthys olivaceus in sea water tank and cage culture systems in Kyung-Nam and Chun-Nam province, Korea. At temperature $15^{\circ}C$ the virus replicated and induced cytopathic effects (CPE), which progressed to eventual cytolysis, in susceptible cell lines, including RTG-2 and EPC. The CHES-214 cell line was refractory. Virus particles were bullet-shaped and measured $70nm{\times}100$ to 150 nm in size. The isolate was sensitive to pH 3, to diethyl ether, and to heat ($50^{\circ}C$ 5 min, $60^{\circ}C$ 1 min). Viral replication was not inhibited by $10^{-4}$ M 5-iododeoxyuridine. Virus infectivity was reduced by anti-HRV (8401-H) rabbit serum, but can not reduced by antisera against infectious hematopoietic necrosis virus (IHNV), chum salmon reovirus (CSV), retrovirus of salmonid (RVS) and infectious pancreatic necrosis virus (IPNV). HRV virus antigen was detected by fluorescent antibody test (FAT) in the cytoplasm of infected EPC cell. Purified isolates virions were composed of: polymerase (L), glycoprotein (G), nucleoprotein (N) and 2 matrix proteins (M1 and M2). Based upon their relative mobilities, the estimated molecular weights of the proteins were: L, 160 kDa; G, 55 kDa; N, 45 kDa; M1, 26 kDa; and M2, 22 kDa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.380-388
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• 2005

Lipid characteristics of 6 species of fish frame (armored weasel-fish, AW; chum salmon, CS; spanish mackerel, SM; common mackerel, CM; conger eel, CE and skipjack tuna, ST) were studied by determining total lipid (TL) contents, lipid classes, and fatty acid composition. The highest yield of bone was obtained from ST frame (64.2%), followed by CS frame (57.9%), CE frame (54.6%), A W frame (41.6%), SM frame (41.7%), and CM frame (32.6%). The highest neutral lipid content was also found in total lipid (TL) from SM bone (23.3 g/100 g), followed by TL from CE bone (21.5 g/100 g), CS bone (16.0 g/100 g), and CM bone (15.5 g/100 g), while those from ST and A W bones were 7.2 g/100 g and 0.4 g/100 g, respectively. The prominent lipid classes of neutral lipids (NL) from all fish bones and muscles were triglyceride (TG), however, which was much lower in AW than in other fishes. The percentages of EPA and DHA in NL from fish bone were in the descending order of CS (29.3%), ST (27.1%), AW (27.0%), CM (25.7%), SM (21.6%), and CE (14.9%). Based on the lipid characteristics, the CS frame was the best resource for extraction of a functional lipid.