• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.3
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• pp.262-277
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• 2018

We seasonally examined marine macroalgal community structures and ocean environmental characteristics in subtidal zones at five sites on and around Jeju Island, Korea, from February 2013 to November 2015. A total of 186 macroalgal species were identified, including 18 green, 33 brown, and 135 red algae. During the study period, the number of species was highest at Gapado Island (125 species) followed by Bukchon (123 species), Sagye (122 species), Sinheung (122 species) and Sinchang (97 species). Ecklonia cava, Peyssonnelia caulifera, Synarthrophyton chejuense, Corallina aberrans and Corallina crassisima occurred at all study sites and in all seasons. The average annual biomass of seaweed was $1,125.10g\;wet\;wt./m^2$ and ranged from $899.77g/m^2$ at Sinheung to $1,452.00g/m^2$ at Gapado. A brown alga E. cava was the most dominant species, accounting for 49.84% ($560.78g/m^2$) of the total seaweed biomass. Subdominant species were C. aberrans and C. crassissima, comprising 6.83% ($76.79g/m^2$) and 5.98% ($67.28g/m^2$) of total biomass, respectively. Cluster analysis revealed three distinct groups: the Sagye/Sinheung group (group A), the Bukchon/Sinchang group (group B), and the Gapado group (group C), indicating significantdifferences in macroalgal communities between sites.

• KIISE Transactions on Computing Practices
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• v.23 no.1
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• pp.74-79
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• 2017

The Geostationary Ocean Color Imager (GOCI), the world's first ocean color sensor operated in a geostationary orbit, can be utilized to mitigate damages by monitoring marine disasters in real time such as red tides, green algae, sargassum, cold pools, typhoons, and so on. In this paper, we described a methodology and procedure for processing GOCI data in order to maximize its utilization potential. The GOCI data processing procedure is divided into data reception, data processing, and data distribution. The kinds of GOCI data are classified as raw, level 1, and level 2. "Raw" refers to an unstructured data type immediately generated after reception by satellite communications. Level 1 is defined as a radiance data type of two dimensions, generated after radiometric and geometric corrections for raw data. Level 2 indicates an ocean color data type from level-1 data using ocean color algorithms.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.4
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• pp.844-853
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• 2005

Red tide(harmful algae) in the Korean Coastal Waters has a given a given damage to the fishery every year. However, the aim of our study understands the influence of meteorological factors (air and water temperature, precipitation sunshine, solar radiation, winds) relating to the mechanism of red tide occurrence and monitors red tide by satellite remote sensing, and analyzes the potential area for red tide occurrence by GIS. The meteorological factors have directly influenced on red tide formation. Thus, We want to predict and apply to red tide formation from statistical analyses on the relationships between red tide formation and meteorological factors. In future, it should be realized the near real time monitoring for red tide by the development of remote sensing technique and the construction of integrated model by the red tide information management system (the data base of red tide - meteorological informations. Finally our purpose is support to the prediction information for the possible red tide occurrence by coastal meteorological information and contribute to reduce the red tide disaster by the prediction technique for red tide.

• Journal of Species Research
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• v.7 no.2
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• pp.104-113
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• 2018

In order to investigate indigenous prokaryotic species diversity in Korea, various environmental samples from diverse ecosystems were examined. Isolated bacterial strains were identified based on 16S rRNA gene sequences, and those exhibiting at least 98.7% sequence similarity with known bacterial species, but not reported in Korea, were selected as unrecorded species. 28 unrecorded bacterial species belonging to the phylum Bacteroidetes were discovered from various habitats including wastewater, freshwater, freshwater sediment, wet land, reclaimed land, plant root, bird feces, seawater, sea sand, tidal flat sediment, a scallop, marine algae, and seaweed. The unrecorded species were assigned to 18 different genera in five families: Flavobacterium, Epilithonimonas, Dokdonia, Gillisia, Flavicella, Chryseobacterium, Algibacter, Aquimarina, Lacinutrix, Gaetbulibacter, Cellulophaga, Tenacibaculum, and Maribacter of Flavobacteriaceae, Dyadobacter of Cytophagaceae, Draconibacterium of Draconibacterium_f, Sunxiuqinia of Prolixibacteraceae, and Fulvivirga of Fulvivirga_f. The selected isolates were subjected to further taxonomic characterization including analysis of Gram reaction, cellular and colonial morphology, biochemical activities, and phylogenetic trees. Descriptive information of the 28 unrecorded species is provided.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.345-353
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• 2014

Copper has been widely used to control algae and pathogens in fish culture ponds. However, its toxic effects on fish depend not only on its concentration in the water but also on the water quality. A laboratory experiment was conducted to assess copper toxicity in the black rockfish Sebastes schlegeli using a panel of antioxidant enzymes, including glutathione (GSH), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) and superoxide dismutase (SOD), at different levels of copper at three water temperatures (WT, 18, 23, $28^{\circ}C$) for 4 days. After exposure to two copper concentrations (100 and $200{\mu}g/L$), GSH levels and GST activities increased significantly, depending on WT (P < 0.05) in the liver, gill, and kidney of the black rockfish. GPx and SOD activities decreased significantly with both increasing WT and copper treatment in the organs of black rockfish (P < 0.05). These changes can be seen as initial responses to temperature stress and as a sustained response to copper exposure. This also indicates that GSH and related enzymes activities were sensitive indexes to stress by toxicants such as copper. The present findings suggest that simultaneous stress due to temperature change and copper exposure can accelerate changes in enzymes activities in the black rockfish. This provides another example of synergism between environmental temperature and pollutants, which may have important implications for the survival of fish in polluted environments during seasonal warming and/or global climate change.

• Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.29-34
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• 2009

Fifty seven species of common seaweed from the coast of Korea were screened for antifungal activity against Malassezia species. Seaweeds as a source of bioactive compounds are able to produce a great variety of secondary metabolites with different activities. There are numerous reports on the biological activities of seaweeds against human pathogens, fungi, and yeasts, but only few contain data regarding inhibitory effects against Malassezia sp., a major cause of dandruff and seborrheic dermatitis. To help address this paucity of information, this work was carried out to examine the antifungal effects of seaweed extracts against M. furfur and M. restricta. Of the fifty seven species of marine algae screened for their potential antifungal activity, only 17 species (29.8%) exhibited inhibitory activity. In agar disc diffusion method, the ether extracts of Corallina pilulifera, Enteromorpha linza, Laminaria japonica, Symphyocladia latiuscula and Ulva sp. showed strong antifungal activity. To identify major constituents in seaweed extracts, four selected extracts were analyzed on' a GC-MS equipped with a flame ionization detector, and compared to spectral data from databases WILEY229.LIB and NIST107.LIB. Most constituents in seaweed extracts are fatty acid-related compounds. When we evaluated any acute toxicity, the ether extracts of the selected four species were not toxic in mice. According to these results, it can be suggested that these seaweed extracts are valuable for the development of therapeutic agents in treating dandruff and seborrheic dermatitis. Further investigations to determine its bioactive compound(s) are currently in progress.

• Journal of the Korean Ceramic Society
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• v.54 no.2
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• pp.108-113
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• 2017

The use of aluminum-based coagulants in water pretreatment is being carefully considered because aluminum exposure is a risk factor for the onset of Alzheimer's disease. Lightly burned-dolomite kiln dust (LB-DKD) was evaluated as an alternative coagulant because it contains high levels of the healthful minerals calcium and magnesium. An organic pore forming agent (OPFA) was incorporated to prepare porous granules after OPFA removal through a thermal decomposition process. A spray drying method was used to produce uniform and reproducible spherical granules with low density, since fine dolomite particles have irregular agglomeration behavior in the hydration reaction. The use of fine dolomite powder and different porosity granules led to a visible color change in raw algae (RA) containing water, from dark green to transparent colorlessness. Also, dolomite powders and granules exhibited a mean removal efficiency of 48.3% in total nitrogen (T-N), a gradual increase in the removal efficiency of total phosphorus (T-P) as granule porosity increased. We demonstrate that porous dolomite granules can improve the settling time and water quality in summer seasons for the emergent treatment of excessive algal blooms in eutrophic water.

• Journal of Species Research
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• v.9 no.4
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• pp.346-361
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• 2020

In the project of a comprehensive investigation of indigenous prokaryotic species in Korea, a total of 39 bacterial strains phylogenetically belonging to the classes Betaproteobacteria and Gammaproteobacteria were isolated from various environmental sources such as soil, cultivated soil, sludge, seawater, marine sediment, algae, human, tree, moss, tidal flat, beach sand and lagoon. Phylogenetic analysis based on 16S rRNA gene sequences revealed that 39 strains showed the high sequence similarities (≥98.7%) to the closest type strains and formed robust phylogenetic clades with closely related species in the classes Betaproteobacteria and Gammaproteobacteria. In the present study, we report 14 species of 9 genera of four families of two orders in the class Betaproteobacteria and 25 species of 21 genera of 15 families of eight orders in the class Gammaproteobacteria, which have not been reported in Korea. Morphological, biochemical, and physiological characteristics, isolation sources, and NIBR deposit numbers are described in the species descriptions.

• Journal of Aquaculture
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• v.2 no.1
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• pp.1-7
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• 1989

Axenic tissue culture of a marine red algae Porphyra yezoensis foma narawaensis was established for the vegetative propagation of tissues as a seed stock and for the development of a low salinity-tolerant cell line. Callus tissues have been induced from the vegetative area of blade away from the hold fast when grown on PES-agar medium. The brownish red fragile callus was maintained under fluorescent light of ca. 2000 lux with 12 : 12 hr L : D at $16^{\circ}C$. Amounts of carbohydrate and protein was determined against the weight of callus. Optimum temperature of the callus growth was $14^{\circ}C\~18^{\circ}C$. Optimun concentration of sodium chloride was $2.0\%$ for the callus growth in PES-agar medium.

• KSBB Journal
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• v.17 no.1
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• pp.63-67
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• 2002

Silver-alginate and copper-alginate were prepared with Na-alginate extracted from marine brown algae(Sargassum fluitans). The antibacterial effect of Ag-alginate or Cu-alginate against Staphylococcus aureus and Escherichia coli was carried out by measuring optical density of liquid culture at 600 nm. The cell growth of Staphylococcus aureus and Escherichia coli was very active at pH 7, and was inhibited by adding Ag-alginate with more than 0.006 wt.% of silver content. The antibacterial effect of Ag-alginate against S. aureus and E. coli was better than that of Cu-alginate at the same metal concentration. The cell growth of S. aureus was less inhibitory than E. coli at the same concentration of Ag-alginate. The cell growth of S. aureus and E. coli was also influenced by the characteristics of counter ion of silver.