• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.3
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• pp.201-207
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• 2008

The seasonal variation and vertical distribution of the marine algal community were investigated using the quadrat method from February 2006 to January 2007 at 10 sites in Gwangyang Bay, Korea. In total, 48 red, 17 brown, and 13 green algal taxa were identified. The algal vertical distribution in the intertidal zone was characterized by Ulva pertusa, while the upper tidal zone was dominated by Gelidium divaricatum. The middle zone was primarily composed of Enteromorpha linza, Sargassum thunbergii, and Chondracanthus intermedia, whereas Hizikia fusiformis, Sargassum thunbergii, Gelidium amansii, and Corallina pilulifera characterized the low tidal zone. Results of cluster analysis indicated that algal composition fell into two groups, which were composed of species in the inland and open sea. In conclusion, the number of species, diversity, and abundance of vegetation in this area were remarkably reduced compared to previous studies in Gwangyang Bay.

• Journal of Environmental Science International
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• v.15 no.4
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• pp.385-386
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• 2006

In 2005, harmful dinoflagellate Cochlodinium polykrikoides was first occurred on July 18 and disappeared on September 12 in the Yeosu waters of the South Sea of Korea. During C. polykrikoides blooms, the species of Protoperidinium was isolated from Jabong Island in Yeosu in the middle of August, 2005. The surface water temperature at the sampling site was $25^{\circ}C$, and salinity was 33.1 psu. The specimen was somewhat large in size and was longer than its width. The shape was close to being ovoid, with an apical horn. This study discovered cells with colorless and transparent ingested chain-forming C. polykrikoides. However, this species was not abundant, implying low grazing impact on C. polykkoides.

• Rapid Communication in Photoscience
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• v.2 no.2
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• pp.52-55
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• 2013

Proteorhodopsin (PR) is a photoinduced proton pump found abundantly in ocean and fresh water habitat, and has an important role in photoenergy conversion to bioenergy in the living cells. Numerous sequences that encode PR protein variants were discovered by environmental genome sequencing and they indicated the high sequence similarity. A new-type of PR (YS-PR) which had been discovered from the surface of Yellow Sea was found to have only 5 amino acid differences from the previously known green-light absorbing PR (GPR) protein, but showed different photochemical properties. This YS-PR showed a 10 nm red-shifted absorption maximum, when compared with GPR. It also showed slower photocycling rate than GPR. However, the photoconversion rate of YS-PR was fast enough to pump protons. Four different amino acids out of 5 were similar to Blue-light absorbing PR (BPR), suggesting that those residues might be responsible for the observed spectral and photoconverting properties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.1
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• pp.20-25
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• 2008

The susceptibility of five different marine fish to iridovirus IVS-1 infection was analyzed and found a higher the cumulative mortality in the order of rock bream (Oplegnathus fasciatus), red sea bream (Pagrus major), sea perch (Lateolabrax sp.), rockfish (Sebastes schlegeli) and black porgy (Acanthopagrus schlegeli). However, the concentrations of virus in the infected spleens of these species did not differ significantly. To determine the release of iridovirus from infected fish into culturing seawater, rock bream were challenged with iridovirus IVS-1 and the concentration of virus in the water was analyzed using PCR. Over the 10 days of the analysis, the linear relationship between the number of dead fish and viral DNA concentration found in culturing seawater should be considered direct evidence of horizontal iridovirus transmission.

• Korean Journal of Pharmacognosy
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• v.35 no.3 s.138
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• pp.203-206
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• 2004

Effects of the EtOH extract from Pelvetia siliquosa on $CCl_4$-induced hepatotoxicity as well as streptozotocin-induced diabetes in rats were investigated. The EtOH extract was found to cause an inhibition of the rise in the transaminase activities in $CCl_4$-intoxicated rats. Also, the EtOH extract exhibited a rat lens aldose reductase inhibition in vitro and showed an inhibition of not only glucose concentrations but also sorbitol accumulations in the lenses, red blood cells and sciatic nerves in the STZ-induced diabetic rats in vivo. These results suggested that this plant might possess hepatoprotective and anti-diabetic activities.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.2
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• pp.117-124
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• 1996

The real size submersible fish cage($L{\times}B{\times}D$, $3{\times}3{\times}6$m)system consists of the compressed air equipment was made in order to control efficiently in case of heavy weather or environmental pollution such as red tide, and then carried out experiment on the submersible functions and safety for that cage at Koje inland sea in 14th June, 1995. The authors could confirm that the submersible cage was very stabilized it's submersible functions and safety when the cage was floating and sinking at sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.613-622
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• 2018

This study investigated changes in the quality and antioxidant activity of soy sauce with added Saccharina japonica powder (FSP). Soy sauce was prepared with acid-hydrolyzed soy sauce, brewed soy sauce, honey, ginger, garlic, dried red pepper, ${\gamma}$-aminobutyric acid (GABA)-enriched sea tangle fermented in lactic acid, and 1% or 3% S. japonica powder by soy sauce volume. The color, pH, microbiology, amino nitrogen, free amino acids, antioxidant activity, and sensory qualities of the soy sauce were evaluated. There were no significant differences in the general characteristics or antioxidant activity. However, the addition of FSP to the soy sauce enhanced the delicate flavor. Furthermore, soy sauce containing FSP had higher levels of GABA (50 mg/100 mL), a biofunctional ingredient. Therefore, the development of seasoning soy sauce with enhanced functionality seems possible.

• Ocean and Polar Research
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• v.34 no.4
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• pp.445-451
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• 2012

The EtOH extracts of red seaweeds (Symphyocladia latiuscula, Chondrus ocellatus and Carpopeltis affinis) and solvent partitioned fractions were investigated for their 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 1,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effects and the total phenolic contents were correlated with ABTS and DPPH radical scavenging activities. The EtOH extracts and their solvent partitioned fractions exhibited strong ABTS and DPPH radical scavenging activities. Among the solvent partitioned fractions obtained from n-Hexane (HX), methylenchloride (MC), ethylacetate (EA), and buthanol (BuOH), the HX fraction from C. affinis showed higher radical scavenging activities than other fractions. Total phenolic contents showed significant correlation ($r^2$ = 0.709) with ABTS radical scavenging activity. The results of this study suggest that the strong radical scavenging activity of HX fraction from C. affinis is a promising natural antioxidant for healthcare products.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.150-155
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• 2002

Marine bacteria producing algicidal substance against Cochlodinium polykrikoides was screened and isolated from seawater. Metabolite of marine bacteria Micrococcus sp. LG-5 showed strong algicidal activity against C. polykrikoides. C. polykrikoides was inhibited above $90\%$ at $5\%$ solution of the metabolite within 24 hrs. Algicidal substance from the metabolite was extracted with ethyl acetate, and then purified by PTLC and reversed-phase HPLC. Algicidal activity of purified compound against C. polykrikoides was above $90\%$ at 3.7, 11.0 and 33.0${\mu}g/mL$ concentration after 12, 9 and 3 hrs, respectively. Ninety percent inhibition of other red tides, Gymnodinium sanguineum and Gyrodinium impudicum was observed when treated with 3.7${\mu}g/mL$ of purified compound within a period of 12 hrs. The microscopic view of red tides treated with purified compound showed the deformations such as cell node cuts and swelling of cells.

• Journal of fish pathology
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• v.25 no.3
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• pp.243-247
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• 2012

Histopathological observations on a epidermal papilloma of wild red halibut (Hippogossoides dubius) caught at the area around Echung Island and Gogunsan Islands were done. The papilloma formed on the dorsal fin was the same color with the body on the ocular side but black on the non-ocular side. Under light microscopy, the tumor on the skin was very similar to epithelial papilloma supported by connective tissue. X-cell-like cells in the tumors were large and eosinophilic with a centrally-located, large nucleus. But the characteristic large nucleolus in the nucleus of the x-like cells was indistinct clear in this specimen because about 6-9 hours have passed after catching the fish and autolysis have occurred.