• Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.258-262
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• 2002

Effects of Escherichia coli genomic DNA on the production of phagocyte activating supernatants by the head kidney leucocytes isolated from olive flounder (Paralichthys olivaceus) were investigated. Phagocyte activating activity of the supernatants was estimated by. measuring reactive oxygen species (ROS) production in target head kidney phagocytes. All supernatants from olive flounder head kidney leucocytes-stimulated with E. coli DNA induced significantly (P<0.01) higher ROS production from target pagocytes than the unstimulated control supernatant. Maximum enhancement of chemiluminescent response was observed $5.0-10.0{\mu}g\;mL^{-1}$ of bacterial DNA while the increment ability was decreased significantly (P<0.01) at the concentration of $20.0{\mu}mL^{-1}$. The results demonstrate that olive flounder head-kidney leucocytes stimulated with bacterial DNA release a soluble phagocyte activating cytokines capable of enhancing the respiratory burst activity from target phagocytes.

• Fisheries and Aquatic Sciences
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• v.6 no.4
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• pp.225-227
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• 2003

Acetylcholinesterase (AChE) activity is a potential biomarker for phenanthrene exposure in aquatic organisms. Olive flounder (Paralichthys olivaceus) were exposed to three different concentrations (0.5, 1.0 and 2.0, uM) of phenanthrene for four weeks. AChE activities in the brain, heart and eyes were documented. Inhibition of AChE activity was found significant in flounder treated with a concentration greater than $1.0 {\mu}M$ of phenanthrene. This indicates that a chronic exposure to phenanthrene induces damage in various organs (brain, heart and eyes) and changes of AChE activities might be a useful biomarker to assess the impacts induced by polycyclic aromatic hydrocarbon (PAH). Evidence from this study confirms that the measurement of AChE in the brain and eyes of flounder is a valuable tool that along with other biomarkers can maximize an ecotoxicologists' confidence in assessing the impacts of oil and PAH pollution in the aquatic environment.

• BMB Reports
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• v.35 no.1
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• pp.54-60
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• 2002

The effects of individual cytokine on apoptosis have been extensively studied. However, the effect of the cytokine combination, or the synergistic effect of cytokines on cell death, has not been widely studied, though synergism between cytokines has been documented in a variety of biological situations. In our effort to identify the final death effector molecule(s) in autoimmune diabetes, we inadvertently became interested in the cytokine synergism. We discovered that $IFN{\gamma}/TNF{\alpha}$ synergism, rather than the Fas ligand as currently believed, is responsible for the apoptosis of pancreatic islet cells both in vitro and in vivo. We also studied similar cytokine synergism in cancer cell deaths, and noted the similarities and dissimilarities between cancer cell death and islet cell death.

• Fisheries and Aquatic Sciences
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• v.6 no.3
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• pp.105-109
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• 2003

Fifty four strains of pathogenic vibrios were isolated from the Gwangan Beach from May to October, 2002. The isolated vibrios were composed of 7 different species: Vibrio parahaemolyticus, V. cholerae non-O1, V. alginolyticus, V. vulnificus, V. hollisae, V. fluvialis, ane V. mimicus. In the detection rate, V. parahaemolyticus was most predominant as $46\%$(25/54). From the isolated strains, only 25 strains have hemolytic activity or 25 strains only proteolytic activity on agar plates. Eleven strains showed both hemolytic and proteolytic activity. No strains showed urease activity. All strains of V parahaemolyticus did not show hemolytic activity, while V. cholerae non-O1 strains showed $\beta$ hemolytic activity. Kanagawa phenomena of pathogenic vibrios did not accord with hemolytic activity of the culture supernatant at the late log phase. Some strains showed high hemolytic activity despite having proteolytic activity, but some weak hemolytic activities despite having no proteolytic activity.

• Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.350-353
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• 2010

This study demonstrated that cryopreserved semen from dead fish can be used for seedling production. Yellow croakers, Larimichthys polyactis, were killed and stored at temperatures of $20^{\circ}C$ or $0^{\circ}C$ for 6 hours. At 2 hour intervals, semen from these fish was collected using abdominal pressure and evaluated for spermatozoa motility and semen cryopreservation. Semen collected after 6 hours from dead fish stored at $0^{\circ}C$ could be cryopreserved and attained fertilization and hatching rates of $15.0{\pm}1.2%$ and $14.8{\pm}1.6%$, respectively. This study suggests that germ cells such as the semen of dead fish can be cryopreserved and utilized in the restoration of a species.

• Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.37-42
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• 2007

The snapping shrimp Alpheus bisincisus is redescribed on the basis of nine specimens collected in southern Korea. This species is readily distinguished from the other reported species of the Edwardsii group of Alpheus from Korea (A. heeia, A. hoplocheles, A. japonicus, A. lobidens, A. malabaricus, A. pacificus, A. richardsoni, and A. sudara) by having the rostrum and rostral triangle on the carapace flattened dorsally and sharply demarked, and by the presence of overhanging orbitorostral grooves.

• Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.35-43
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• 2009

Sturgeons and paddlefishes are frequently referred to as 'living fossils' among the actionpterygian lineage. They are increasingly facing threats to their existence because of various anthropogenic pressures. In this study, we present the complete mitogenome sequence of the Russian sturgeon Acipenser gueldenstaedtii (Acipenseriformes; Acipenseridae). The mitogenome showed highly homogeneous molecular features compared to previously known vertebrate mitogenomes. Phylogenetic tree inferred from concatenated protein-coding and tRNA genes unambiguously revealed the monophyly of A. gueldenstaedtii, Acipenser stellatus, and Huso huso. Genetic information of the endangered A. gueldenstaedtii will provide baseline data needed to develop molecular markers for stock identification and assessment of population diversity and also to develop future conservation strategies.

• Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.16-23
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• 2009

Lipids were extracted from marine rotifer, Brachionus rotundiformis in order to examine the functionality of lipid enzymatic modification. The fatty acids, palmitic, linoleic, oleic and stearic acids were the dominant forms accounting for approximately 35.8%, 21.5%, 15.9% and 7.7% of the total lipid content, respectively. Lipid fractions were categorized as neutral lipids (38.5%), glycolipids (45.9%) and phospholipids (17.6%), and after extraction from the rotifer were isolated by thin-layer chromatography (TLC) as free fatty acids (FFA), monoacylglycerol (MAG), diacylglycerol (DAG) and triacylglycerol (TAG). The production of polyunsaturated fatty acid (PUFA) concentrate from rotifer lipids was studied using lipase-catalyzed hydrolysis. In addition, rotifer lipids were modified by hydrolysis using lipases such as porcine pancreas, Candida rugosa and Rhizomucor miehei. The lipase from Rhizomucor miehei was effective in extracting linoleic acid (C 18:2), while the lipase from Candida rugosa was effective in palmitic acid (C16:0) extraction.

• Fisheries and Aquatic Sciences
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• v.7 no.1
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• pp.46-50
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• 2004

Feeding habits of Rudarius ercodes collected from a Zostera marina bed in Jindong Bay, Korea were studied. R. ercodes was a omnivore which consumed mainly gammarid amphipods, polychaetes and eelgrass (z. marina). Its diets also included a small amount of copepods, urochordates and caprellid amphipods. R. ercodes showed ontogenetic changes in feeding habits. Small individuals less than 2cm SL fed mainly on copepods, however, gammarid amphipods and polychaetes were heavily selected with increasing fish size. The consumption of eelgrass by R. ercodes was $10-20\%$ all size classes. The dietary breadth of R. ercodes were varied with fish size

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.57-62
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• 2012

Interspecific relationship between a euryhaline rotifer Brachionus rotundiformis and a cyclopoid copepod Apocyclops borneoensis was investigated in the laboratory culture. In a mixed culture of B. rotundiformis and A. borneoensis, population growth of B. rotundiformis was suppressed from day 10, while growth in a monoculture population continuously increased throughout the experimental period. However, the population growth of A. borneoensis in the mixed culture did not markedly differ from that in a monoculture population. Suppression of B. rotundiformis growth coincided with a decrease in the numbers of both non-egg-bearing and egg-bearing females, and increasing resting egg formation. Growth of A. borneoensis was not affected by the presence of the rotifer. However, relative growth index of ovisac bearing females in the mixed culture was 1.62 times higher than that in the monoculture. Presence of the copepod did not greatly reduce the food available to the rotifer population. The rotifer B. rotundiformis responded in a unique way, to stresses such as physical damage (filtering by A. borneoensis) with the production of many resting eggs to increase its chances of survival.