• ALGAE
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• v.32 no.1
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• pp.75-86
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• 2017

Polysaccharides of marine algae exhibit different structural characteristics and interesting biological functions. In this study, crude polysaccharides (CP) of eleven Sri Lankan marine algae obtained through hot water extraction and ethanol precipitation were investigated for DPPH, alkyl, and hydroxyl radical scavenging activities using electron spin resonance spectrometry and for intracellular reactive oxygen species scavenging activity in the Chang liver cell line. Characterization of CPs was done by Fourier transform infrared (FTIR) spectroscopy and by analysis of the monosaccharide composition. Time-dependent density functional theory quantum-chemical calculations at the RB3LYP/6-31G(d,p) level for constructed dimeric units of the corresponding polysaccharides were used to resolve the FTIR spectra. CPs from Chnoospora minima showed the highest DPPH and alkyl radical scavenging activities and higher intracellular reactive oxygen species scavenging effects for both AAPH and $H_2O_2$ induced ROS production in "Chang" cells. The major polysaccharide constituent in C. minima CP was identified as fucoidan and it displayed a higher sulfate content. The degree of sulfation of these polysaccharides suggests a positive correlation with the observed antioxidant properties.

• Journal of fish pathology
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• v.29 no.1
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• pp.1-5
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• 2016

Isopods are parasitic crustaceans that pose serious threat to fisheries. Several studies have tried to explore the host-pathogen relationship between marine fishes and isopods. The present study aims to understanding the secondary infections in marine fishes pertaining to isopods. To assess the secondary infection in infected fishes, parasite infested and healthy tissues of fishes were collected. The samples were subjected to standard microbiological procedure to identify the presence of pathogenic bacteria and fungi. Our results showed the branchial region had the higher microbial load of non-sporulating cenocytic fungi in infected fishes. Moreover, fungal strains isolated from the parasitic lesion confirmed that the parasitation and body lesion facilitates the entry of several pathogenic microbes at the damaged host tissue. More over the immune regulation of fish fights back by producing minute cysts, trying to encapsulate the growing fungus. But this may eventually lead to systemic infestation and death of the fish.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.221-226
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• 2015

During the study periods, total 143 individuals of Lateolabrax japonicus were collected. Body length (BL) range was 2.0-11.8 cm. Empty stomach occurred in 8.4%. The most abundant prey was copepods. Among copepods, Tigriopus japonicus was the most abundant prey appeared 32.1 in %F. Next important prey was shrimps and mysids. The results of analysis in ontogenetic changes, main prey of two small size classes (2.0-3.9 cm, 4.0-5.9 cm) were copepods. Thereafter, copepods percentage was decreased, but shrimps, mysids, fishes percentage was increased by increasing body length from 8.0 cm< size class.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.65-104
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• 2007

This catalogue is the result of a four-year survey of the mollusks of Jeju Island, the southernmost island in the Republic of Korea. Forty-eight survey stations were visited, with a total of 82 specific localities being sampled. Literature records were also obtained. Local and world distribution of each species is included. This survey reports a total of 1,072 mollusk species and subspecies; 1,015 marine and 57 land and freshwater. There are 812 gastropods, of which 755 are either entirely marine or have marine affinities. The best represented of the marine families are the Pyramidellidae, Trochidae, and Ovulidae. There are 225 bivalves, none being freshwater species, with the Veneridae, Mytilidae, and Arcidae having the largest number of species. Among the smaller classes there are sixteen Cephalopoda, eleven Polyplacophora, and eight Scaphopoda. Compared to mainland Korea, Jeju Island has a rather small terrestrial mollusk fauna and a depauperate freshwater one, with mainly Palearctic connections. The Helixarionidae and Bradybaenidae are the largest terrestrial families. The marine faunal affinities with the neighboring Japonic and Indo-West Pacific provinces are also discussed, revealing that this island's mollusk fauna is a blend of warm-temperate and subtropical-tropical species.

• Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.35-47
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• 2024

The aim of this study was to analyze the income and productivity of seaweed farmers based on farmed land ownership status. This research was conducted in three provinces on the Sulawesi Island which are ranked among the 10 largest seaweed producers in Indonesia: Central Sulawesi, South Sulawesi and Southeast Sulawesi. The twelve study sites were determined based on 5 special criteria and 792 respondents fulfilled the criteria for seaweed farmers. Data were collected through field surveys and analyzed using qualitative and quantitative methods. Results showed that the seaweed farming areas are considered as private property with 4 types of marine land tenure or ownership status: own land, inherited land, leasehold land and purchased land. The productivity of seaweed farming land had a positive value greater than 1 in South Sulawesi and Southeast Sulawesi, and a positive value of less than 1 in Central Sulawesi. Seaweed cultivation in Central Sulawesi has not been managed effectively. At all sites, the maximum number of growing season cycles was 5 cycles/year. Optimal growing season conditions gave the highest marginal returns at 2-3 cycles/year with additional costs exceeding additional income for more than 3 cycles/year.

• Journal of fish pathology
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• v.23 no.2
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• pp.177-187
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• 2010

The Interferon stimulated gene 15 (ISG15) is strongly induced in many cell types by IFNs, viral infections, and double-stranded RNA (poly I:C). The ISG15 homologue cDNA was isolated from the rock bream LPS stimulated leukocyte cDNA library. The rock bream ISG15 homologue was found to consist of 833 bp encoding 157 amino acid residues. Compared with other known ISG15 peptide sequences, the most conserved regions of the rock bream ISG15 peptide were found to be the tandem ubiquitin-like domains and a C-terminal LRLRGG conjugating motif, characteristic of mammalian and non-mammalian ISG15 proteins. Phylogenetic analysis based on the deduced amino acid sequence revealed a homologous relationship between the ISG15 sequence of rock bream and that of Atlantic salmon, Atlantic cod, northern snake head, black rockfish and olive flounder. The expression of the rock bream ISG15 molecule was induced in the peripheral blood leukocytes (PBLs) from 1 to 24 h following poly I:C stimulation, with a peak at 3 h post-stimulation. The rock bream ISG15 gene was predominantly expressed in the PBLs, spleen and gill.

• Proceedings of the KSCN Conference
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• 2004.12a
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• pp.97-97
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• 2004

• Proceedings of the KSCN Conference
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• 2004.12a
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• pp.98-98
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• 2004

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.87-92
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• 2007

New type of seasoned and dried oyster slice (SDOS) was prepared with surimi and oyster, and then characterized on the food components. With a higher oyster content ratio, the moisture (18.1% to 21.7%), water activity (0.621 to 0.661), and $\Delta$E value (74.83 to 75.90) of SDOS slightly increased. Regardless of differences in oyster content ratios, there was, however, no difference in the sensory color and flavor expect for sensory texture of SDOS. The desirable ratio of oyster content for preparing the seasoned and dried oyster slice was determined as 30% according to the results above. There was no difference in total amino acid content between seasoned and dried slices with and without oyster. The major amino acids of SDOS were glutamic acid, leucine, lysine and threonine. The calcium and phosphorus contents of SDOS were 64.4 mg/100 g and 315.9 mg/100 g, respectively. The total free amino acid content and taste value of SDOS were 1,576.8 mg/100 g and 226.05, respectively. The results suggested that SDOS could be used as jerky-like oyster products.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.432-438
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• 2018

Microalgae hold promise as a renewable energy source for the production of biofuel, as they can convert light energy into chemical energy through photosynthesis. However, cost-efficient harvest of microalgae remains a major challenge to commercial-scale algal biofuel production. We first investigated the potential of electrolytic water as a flocculant for harvesting Tetraselmis sp. Alkaline electrolyzed water (AEW) is produced at the cathode through water electrolysis. It contains mineral ions such as $Na^+$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ that can act as flocculants. The flocculation activity with AEW was evaluated via culture density, AEW concentration, medium pH, settling time, and ionic strength analyses. The flocculation efficiency was 88.7% at 20% AEW (pH 8, 10 min) with a biomass concentration of 2 g/l. The initial biomass concentration and medium pH had significant influences on the flocculation activity of AEW. A viability test of flocculated microalgal cells was conducted using Evans blue stain, and the cells appeared intact. Furthermore, the growth rate of Tetraselmis sp. in recycled flocculation medium was similar to the growth rate in fresh F/2 medium. Our results suggested that AEW flocculation could be a very useful and affordable methodology for fresh biomass harvesting with environmentally friendly easy operation in part of the algal biofuel production process.