• 한국해양바이오학회지
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• 제6권2호
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• pp.68-75
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• 2014

This study investigated the potential use of various organic carbon sources (glucose, glycerol and acetate) and different concentrations of $CO_2$ for culturing marine microalga Dunaliella tertiolecta. Cell growth and lipid production were monitored under heterotrophic, mixotrophic and photoautotrophic modes of cultivation. D. tertiolecta showed the ability to grow under mixotrophic (acetate and glucose), heterotrophic (glucose) and photoautotrophic condition under high $CO_2$ concentration (15%). With all the organic carbon sources (glucose, glycerol and acetate) tested in this study, 1~5% acetate enhanced cell growth rate and lipid content, while higher concentrations of acetate (10% and 15%) were inhibitory and resulted in cell death.

• 환경생물
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• 제35권4호
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• pp.521-525
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• 2017

A marine algal species belonging to Gigartinales was collected from Geoje, Korea. This shares the generic features of Ahnfeltiopsis, such as multiaxial thalli with a compact and pseudoparenchymatous medulla, densely cytoplasmic secondary medullary cells around immersed cystocarps with a carpostome, and is distinct from similar species within the genus by a combined feature of small (up to 4 cm tall) and tuft thalli, compressed to subcompressed branches except for ultimate branchlets and base of main axes, cartilaginous in texture, dichotomous branches, rarely produced proliferations, absence of hypha-like filament in the medulla and internal cystocarps with a carpostome. In phylogenetic tree based on rbcL sequence, the Korean species nests in the same clade with Ahnfeltiopsis linearis. The genetic distance between both sequences within the clade was 1.5%, considered to be within the intra-species range for the genus. This morphological and molecular evidence confirms the Korean alga to be identified as A. linearis originally described from California. This is the first record of A. linearis in Korea.

• ALGAE
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• 제18권4호
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• pp.349-354
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• 2003

This paper reports that the heavy metal accumulation in marine seaweeds. Algal samples collected from Korean coast were analyzed to determine the concentrations of Cu, Cd, Cr, Zn and Pb. In general, heavy metals were found to be concentrated in many kinds of Korean seaweeds. The concentration levels of accumulated heavy metals in the marine seaweeds was in the following order: Zn > Cu > Cr > Pb > Cd. The concentrations of the heavy metals in the seawater were the highest in Iyajin harbor. Sargassum horneri, a brown alga accumulated high concentrations of Cu (80.66 ${\mu}g{\cdot}g^{-1}$ dw) and Cr (31.54 ${\mu}g{\cdot}g^{-1}$ dw). The high concentrations of heavy metals were accumulated in the brown algae.

• 한국수산과학회지
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• 제47권1호
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• pp.45-51
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• 2014

Scuticociliates are regarded as serious pathogens in marine aquaculture worldwide. In Korea, they cause mass-mortalities in fish such as the commercially important olive flounder Paralichthys olivaceus. In particular, mixed infections of scuticociliates with pathogenic bacteria have been commonly reported. During efforts to identify natural marine-algae derived products that possess anti-bacterial and anti-scuticociliate properties, we found that an 80% methanolic extract of the red alga Polysiphonia morrowii Harvey exhibits both anti-scuticociliate activity against Miamiensis avidus, which is a major causative agent of scuticociliatosis, and anti-bacterial activities against fish pathogenic bacteria. Activity-guided fractionation and isolation of the 80% methanolic extract of P. morrowii yielded three bromophenols, which were identified as 3-bromo-4,5-dihydroxybenzyl methyl ether (1), 3-bromo-4,5-dihydroxybenzaldehyde (2) and urceolatol (3) based on spectroscopic analyses. 3-bromo-4,5-dihydroxybenzyl methyl ether (1) showed the highest anti-bacterial and anti-scuticociliate activities, with a minimal inhibitory concentration (MIC) of $62.5{\mu}g/mL$ (against Vibrio anguillarum) and minimal lethal concentration (MLC) of 62.5 ppm (in seawater). Investigations of the anti-bacterial and anti-scuticociliate activities of seventeen bromophenol derivatives, including the three isolated natural bromophenols, showed that the existence of an electron donating group or atom with a non-covalent electron pair at $C_4$ of the 2-bromophenol structure may be important in anti-scuticociliate activity. These findings suggest that the extract and bromophenol derivatives of P. morrowii may provide useful alternatives in aquaculture anti-scuticociliate therapies.

• Fisheries and Aquatic Sciences
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• 제4권4호
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• pp.257-260
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• 2001

The effects of light, desiccation and salinity on the discharge of spores in Korean agarophyte, Gracilaria verrucosa were studied. Among the examined factors, light after darkness was the most effective for spore discharge. The maximum release of tetraspores was induced at 24 h after the treatment. Desiccation also seems to be conductive to the release of tetraspores. However, its effect, as in treatment of distilled water for salinity, was hardly found in induction of carpospore discharge. This may suggest that spore discharge in this alga is primarily related with photoperiodic rhythm. Also it appears that the amount of light energy received by fertile thalli also significantly affects to the spore release, considering relationship between the amount of the discharged spores and the elapsed time after treatment.

• Journal of Ecology and Environment
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• 제38권4호
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• pp.655-661
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• 2015

A marine algal species was collected from the southern coast of Korea. This alga is characterized by a large and cartilaginous thallus, a dichotomous branching pattern, compressed axes, rare proliferations near the apex, and cystocarps protruded toward surface. In a phylogenetic tree based on rbcL sequences, this species nests in the same clade as Neodilsea yendoana as a terminal clade of the genus Neodilsea. The genetic distance between both sequences within the clade was calculated as 0.2% considered to be in the intraspecific range within the genus. Based on the morphological and molecular data obtained in the present study, this Korean species is identified as N. yendoana. This is the first record of the genus Neodilsea and N. yendoana in Korea.

• Food Science and Biotechnology
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• 제17권5호
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• pp.1110-1114
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• 2008

$\beta$-Glucuronidases of intestinal bacteria are capable of retoxifying compounds that have been detoxified by liver glucuronidation, which is one of the most important detoxication processes in the liver. Therefore, this enzyme is known to accelerate colon cancer invasion and metastasis. Two bromophenols, 2,4,6-tribromophenol (I) and 2,4-dibromophenol (II), were purified from the red alga Grateloupia elliptica. $IC_{50}$ values of bromophenol I and II against Escherichia coli $\beta$-glucuronidase were 5.4 and 8.5 mg/mL, respectively. Hence, bromophenols of G. elliptica, a potent $\beta$-glucuronidase inhibitor, can be used as a novel pharmaceutical agent for the prevention and treatment of colon cancer.

• ALGAE
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• 제17권2호
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• pp.127-133
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• 2002

The red seaweed Eucheuma serra is a high yielding source of lectins. The plants were collected from a depth of 5-6 meters and cultured in the laboratory, field and deep seawater. A Daily Growht Rate (DGR) of 3.5% was observed at 18℃ with a low light of 30μmol photon $ m^{-2} · s^{_1}$ in the laboratory. When the plants were cultured in the field at different depths during winter onths of December and January, best growth was observed at 1 m depth and a DGR of 2.14±0.04% was recorded. The plants grown in the tank with a continuous supply of deep seawater showed a DGR of 8.2% The results indicate that E. serra can be cultivated in large scale both in deep seawater in the tank and in the field for the extraction of lectins at a commercial scale.

• ALGAE
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• 제31권2호
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• pp.129-136
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• 2016

The Mediterranean Sea is currently facing dramatic changes and threats, including change in native species and accidental introductions. The introduced green alga Codium fragile subsp. fragile (Suringar) Hariot influences diversity and community structure in some parts of the world. This paper documents the distribution of this species in Tunisia and provides a morphological description of C. fragile subsp. fragile in Northern Tunisia. Results confirm the identity of Tunisian specimens as the invasive subspecies C. fragile subsp. fragile. This is the first morphological characterization of this subspecies in Tunisia.

• Archives of Pharmacal Research
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• 제26권1호
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• pp.21-23
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• 2003

Indolyl alkaloids, $N_b-acetyltryptamine$ (1) and the known oxaline (2) have been isolated from the organic extract of the broth of an unidentified fungus collected from the surface of the marine red alga Gracilaria verrucosa. The structure of $N_{b}$-acetyltryptamine (1) was assigned on the basis of comprehensive spectroscopic analyses.s.