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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Fisheries and aquatic sciences
Journal Basic Information
Journal DOI :
The Korean Society of Fisheries and Aquatic Science
Editor in Chief :
Sungchul C. Bai
Volume & Issues
Volume 14, Issue 4 - Dec 2011
Volume 14, Issue 3 - Sep 2011
Volume 14, Issue 2 - Jun 2011
Volume 14, Issue 1 - Mar 2011
Selecting the target year
Anti-hyperlipidemia and Anti-arteriosclerosis Effects of Laminaria japonica in Sprague-Dawley Rats
Lee, Seung-Joo ; Kim, Chong-Wook ; Jang, Hyuk-Jai ; Cho, Soon-Yeong ; Choi, Jong-Won ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 235~241
DOI : 10.5657/FAS.2011.0235
The anti-hyperlipidemic effects of dietary supplementation with sea tangle Laminaria japonica were investigated using an animal model in which normal rats were fed either sea tangle, sea tangle ethanol extract (EE-ST) and sea tangle extracted residue (ER-ST). Total lipid and triglyceride levels in the serum were significantly (P < 0.05) reduced in rats fed ER-ST at a dose of 200 mg/kg body weight when compared to hyperlipidemic control rats. Significant decreases in serum total cholesterol and low density lipoprotein-cholesterol levels also occurred in rats fed ER-ST at 200 mg/kg body weight. In addition, the atherosclerosis index and superoxide dismutase in blood lipids were significantly (P < 0.05) lowered in rats fed ER-ST at 200 mg/kg body weight as compared to control rats. In conclusion, sea tangle and ER-ST exhibited beneficial anti-hyperlipidemic and anti-arteriosclerosis effects.
Antioxidative Activity of Carotenoids in Mideodeok Styela clava
Nacional, Loda M. ; Kang, Seok-Joong ; Choi, Byeong-Dae ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 243~249
DOI : 10.5657/FAS.2011.0243
Carotenoids were found in high levels in both muscle and tunic samples, with the highest and lowest values observed in March and January, respectively. The average values in muscle (GM) and tunic (GT) harvested in Geoje were 49.1 mg/100g and 56.7 mg/100g, respectively, whereas those in muscle (TM) and tunic (TT) harvested in Tongyeong were 42.0 mg/100g and 50.2 mg/100g, respectively. The total phenol contents of the tunic were not significantly different (P < 0.05) between sampling area and month. We investigated the antioxidative activities of the carotenoids against linoleic acid peroxidation [1,1-diphenyl-2-picrylhydrazyl (DPPH)] and hydroxyl radicals as well as their reducing power. The DPPH radical scavenging activity was 7.6-13.5% in GM, which is relatively weak, whereas it was 21.1-29.9% in GT, 9.6-12.4% in TM and 19.3-24.1% in TT. In comparison to
-tocopherol, the carotenoids were found to have strong inhibitory effects against linoleic acid peroxidation, and exhibited strong hydroxyl radical scavenging activities and reducing power at 120
of each sample.
Antimicrobial Activity of Brown Alga Eisenia bicyclis against Methicillin-resistant Staphylococcus aureus
Eom, Sung-Hwan ; Park, Jae-Hong ; Yu, Dae-Ung ; Choi, Ji-Il ; Choi, Jong-Duck ; Lee, Myung-Suk ; Kim, Young-Mog ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 251~256
DOI : 10.5657/FAS.2011.0251
We screened for antibacterial substances against methicillin-resistant Staphylococcus aureus (MRSA). Methanolic extract of Eisenia bicyclis exhibited anti-MRSA activity according to a disk diffusion assay. To identify the active compound(s), the methanolic extract was further fractionated using hexane, dichloromethane, ethyl acetate, and n-butanol. The ethyl acetate-soluble fraction showed both the greatest anti-MRSA activity and the highest polyphenol content. The minimum inhibitory concentrations of the ethyl acetate fraction ranged from 32 to 64
per mL against methicillin-susceptible S. aureus and MRSA strains. High-performance liquid chromatography analysis revealed that both the methanolic extract and the ethyl acetate soluble fraction contained sizeable quantities of dieckol, which is a known anti-MRSA compound. Thus, these data strongly suggest that the anti-MRSA activity of E. bicyclis may be mediated by phlorotannins such as dieckol.
Effects of Cooking Conditions on the Protein Quality of Chub Mackerel Scomber japonicus
Oduro, Frieda A. ; Choi, Nam-Do ; Ryu, Hong-Soo ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 257~265
DOI : 10.5657/FAS.2011.0257
The effects of cooking method (grilling, frying, steaming, and microwaving) on the proximate composition and protein quality of chub mackerel Scomber japonicus treated with 2, 6, and 10% sodium chloride (NaCl) brine were investigated. Moisture content decreased in all cooked samples from 60.22% in the raw sample to 48.7% in the fried samples. Brine (10% NaCl) treatment recorded the highest moisture loss. All cooked samples showed a decrease in fat content, except fried samples. Protein content increased in all cooked samples, from 47.21% in the raw sample to 63.87% in the grilled sample. Brine treatment resulted in the highest degree of fat oxidation (thiobarbituric acid-reactive substances), which was highest in the fried samples and lowest in the microwaved samples. The trypsin inhibitor (TI) concentration was highest in the microwaved samples and lowest in the fried samples. In all samples, 6% salt treatment caused the lowest TI level and the highest in vitro protein digestibility. In vitro digestibility increased from 79.4% in the raw sample to 86.43% in the fried samples. The total essential amino acids of all cooked samples increased. Results suggested that grilling and steaming had beneficial effects on the protein quality of chub mackerel.
Anti-inflammatory Effects of Ethanolic Extracts from Codium fragile on LPS-Stimulated RAW 264.7 Macrophages via Nuclear Factor kappaB Inactivation
Yoon, Ho-Dong ; Jeong, Eun-Ji ; Choi, Ji-Woong ; Lee, Min-Sup ; Park, Myoung-Ae ; Yoon, Na-Young ; Kim, Yeon-Kye ; Cho, Deuk-Moon ; Kim, Jae-Il ; Kim, Hyeung-Rak ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 267~274
DOI : 10.5657/FAS.2011.0267
Bacterial lipopolysaccharide (LPS) induces expression of pro-inflammatory cytokines and enzymes producing nitric oxide (NO) and prostaglandins (PGs) in immune cells. This process is mediated by the activation of nuclear factor kappaB (NF-
). In this study, we investigated the anti-inflammatory characteristics of Codium fragile ethanolic extract (CFE) mediated by the regulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) using LPS-stimulated murine macrophage RAW 264.7 cells. CFE significantly inhibited LPS-induced NO and
production in a dose-dependent manner and suppressed the expression of iNOS and COX-2 proteins in LPS-stimulated RAW 264.7 cells with no cytotoxicity. Pro-inflammatory cytokines, such as interleukin (IL)-
, IL-6, and tumor necrosis factor-
, were significantly reduced by treatment of CFE in LPS-stimulated RAW 264.7 cells. CFE inhibited the promoter activity of (NF)-
in LPS-stimulated macrophages. Treatment with CFE suppressed translocation of the NF-
p65 subunit by preventing proteolytic degradation of inhibitor of
. These results indicate that the CFE-mediated inhibition of NO and
production in LPS-stimulated RAW 264.7 cells is mediated through the NF-
-dependent transcriptional downregulation of iNOS and COX-2, suggesting the potential of CFE as a nutraceutical with anti-inflammatory activity.
Ethanolic Extract of Chondria crassicaulis Inhibits the Expression of Inducible Nitric Oxide Synthase and Cyclooxygenase-2 in LPS-Stimulated RAW 264.7 Macrophages
Kim, Yeon-Kye ; Jeong, Eun-Ji ; Lee, Min-Sup ; Yoon, Na-Young ; Yoon, Ho-Dong ; Kim, Jae-Il ; Kim, Hyeung-Rak ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 275~282
DOI : 10.5657/FAS.2011.0275
Inflammatory mediators such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) have been implicated in various inflammatory diseases. In this study, we investigated the anti-inflammatory activities of Chondria crassicaulis ethanolic extract (CCE) by measuring its effects on the expression of iNOS and COX-2 proteins in lipopolysaccharide (LPS)-treated RAW 264.7 murine macrophages. CCE significantly and dose-dependently inhibited the LPS-induced release of nitric oxide and prostaglandin
, and suppressed the expression of iNOS and COX-2 proteins in LPS-stimulated RAW 264.7 cells, without causing any cytotoxicity. It also inhibited the production of the pro-inflammatory cytokines such as interleukin (IL)-
, IL-6, and tumor necrosis factor (TNF)-
in LPS-stimulated RAW 264.7 cells. Moreover, treatment with CCE strongly suppressed nuclear factor-
) promoter-driven expression in LPS-treated RAW 264.7 cells. CCE treatment blocked nuclear translocation of the p65 subunit of NF-
by preventing proteolytic degradation of inhibitor of
. These results indicate that CCE regulates iNOS and COX-2 expression through NF-
-dependent transcriptional control, and identifies potential candidates for the treatment or prevention of inflammatory diseases.
Dipeptide (Tyr-Ile) Acting as an Inhibitor of Angiotensin-I-Converting Enzyme (ACE) from the Hydrolysate of Jellyfish Nemopilema nomurai
Kim, Yeon-Kye ; Lim, Chi-Won ; Yeun, So-Mi ; Lee, Moon-Hee ; Moon, Ho-Sung ; Cho, Hyeon-Ah ; Yoon, Na-Young ; Yoon, Ho-Dong ; Park, Hee-Yeon ; Lee, Doo-Seog ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 283~288
DOI : 10.5657/FAS.2011.0283
The jellyfish Nemopilema nomurai was hydrolyzed with papain and a novel dipeptide purified via ultrafiltration, gel filtration chromatography with Sephadex LH-20, and reverse phase chromatography using
columns. The IR, 1H NMR, 13C NMR, and MS spectrometer analyses showed that the dipeptide comprised tyrosine-isoleucine (Tyr-Ile). The
, respectively, indicating competitive inhibition of angiotensin-I-converting enzyme (ACE). As a novel ACE-inhibitory active peptide, Tyr-Ile may have potential for use in antihypertensive therapy.
Antioxidant and Cholinesterase Inhibitory Activities of Antarctic Krill Eupausia superba
Yoon, Na-Young ; Xie, Chengliang ; Shim, Kil-Bo ; Kim, Yeon-Kye ; Lee, Doo-Seog ; Yoon, Ho-Dong ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 289~293
DOI : 10.5657/FAS.2011.0289
The antioxidant and cholinesterase inhibitory activities of methanol, pretanol, and acetone extracts of Eupausia superba were investigated and their bioactivities compared. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis[3-ethylbenzthiazoline-6-sulfonic acid] (
) radical-scavenging activities and reducing power assays were used to determine antioxidant activities, and Ellman's colorimetric methods were applied to evaluate cholinesterase inhibitory activity. Although all extracts were positive, Acetone extract of E. superba showed the highest activities. However, these showed moderate or no inhibitory activity against butyrylcholinesterase. Moreover, the total carotenoid contents of the organic solvent extracts followed the same order as their antioxidant and acetylcholinesterase inhibitory activities. These results suggest that E. superba is a potential source of natural antioxidants and cholinesterase inhibitors.
Genetic Structure in Wild Populations of Ayu Plecoglossus altivelis in Korea and Japan
Han, Hyon-Sob ; Taniguchi, Nobuhiko ; Lee, Jong-Ha ; Yoon, Moon-Geun ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 295~301
DOI : 10.5657/FAS.2011.0295
We investigated the genetic structure of Korean and Japanese ayu Plecoglossus altivelis populations by examining 669 individuals from 14 populations using three microsatellite loci. Genetic variation did not differ significantly among the populations examined in terms of allelic number and heterozygosity. Korean populations were genetically close to each other, implying that persistent gene flow has occurred in these populations. This suggests that eastern populations in Korea form a single large population and all of the Korean populations are distinct from the Japanese populations. Pairwise population
estimates, principal component analyses, and a neighbor-joining tree showed that genetic separation between the southern and pooled eastern coast populations was probably influenced by restricted gene flow. Hierarchical analysis of molecular variance (AMOVA) revealed a weak but significant genetic structure among three ayu groups (eastern and southern coasts of Korea and the Japan coast), and no genetic variation within groups. The estimated genetic population structure and potential applications of microsatellite markers may aid in the proper management of ayu populations.
Tail-to-Head Tandem Duplication and Simple Repetitive Sequences of the Cytoplasmic Actin Genes in Greenling Hexagrammos otakii (Teleostei; Scorpaeniformes)
Lee, Sang-Yoon ; Kim, Dong-Soo ; Nam, Yoon-Kwon ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 303~310
DOI : 10.5657/FAS.2011.0303
We characterized a cytoplasmic actin gene locus in greenling Hexagrammos otakii (Scorpaeniformes). Genomic clones isolated from the greenling DNA library contained two homologous cytoplasmic actin gene copies (HObact2.1 and HObact2.2) in a tail-to-head orientation. Their gene structure is characterized by six translated exons and one non-translated exon. Exon-intron organization and the nucleotide sequences of the two actin gene isoforms are very similar. However, only the HObact2.1 isoform contains microsatellite-like, dinucleotide repeats in the 5'-flanking region (named HOms2002) and intron 1 following the non-translated exon 1 (named HOms769). One microsatellite locus (HOms769) was highly polymorphic while the other (HOms2002) was not. Based on bioinformatic analysis, different transcription factor binding motifs are related to stress and immune responses in the two actin isoforms. Semiquantitative and real-time reverse transcription-PCR assays showed that both isoform transcripts were detectable ubiquitously in all the tissues examined. However, the basal expression levels of each isoform varied across tissues. Overall, the two isoforms showed a similar, but not identical, expression pattern. Our data suggest that the cytoplasmic actin genes may be the result of a recent duplication event in the greenling genome, which has not experienced significant subfunctionalization in their housekeeping roles.
Effect of Dietary Starch Level and Kind on the Growth and Body Composition of Juvenile Olive Flounder Paralichthys olivaceus
Lee, Sang-Min ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 311~315
DOI : 10.5657/FAS.2011.0311
A 7-week feeding trial was conducted to investigate the effect of dietary starch level and kind on the growth and body composition of juvenile olive flounder. Triplicate groups of fish (average weight: 1.5 g) were fed iso-nitrogenous (48% crude protein) and isocaloric (4.8 kcal/g diet) diets containing 15-25%
-potato starch and 15%
-potato starch. Survival was not affected by dietary starch level and kind. The weight gain of fish fed the diet containing 20%
-potato starch was significantly higher than that of fish fed the diets containing 15% and 25%
-potato starch levels. The feed efficiency and protein efficiency ratios of fish fed the diets containing 15%
-potato starch were significantly lower than those of the other groups (P < 0.05). The protein efficiency ratio tended to increase with increasing
-potato starch. The daily feed intake of fish fed the diet containing 15%
-potato starch was significantly higher than that of the other groups (P < 0.05). The hepatosomatic index, condition factor, and proximate composition of the whole body were not affected by the dietary starch level and kind. These results indicate that up to 20%
-potato starch could be incorporated into the juvenile flounder diet for optimum growth.
Development of Economical Fertilizer-Based Media for Mass Culturing of Nannochloropsis oceanica
Bae, Jean-Hee ; Hur, Sung-Bum ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 317~322
DOI : 10.5657/FAS.2011.0317
This study was conducted to develop economical agricultural fertilizer media for the mass culturing of Nannochloropsis oceanica. Specific growth rates of N. oceanica cultured with differing concentrations of commercial compounds, urea fertilizers, and trace elements (Zn, Cu, Co, Mo) were compared with the growth rate in f/2 medium. Among the various added trace elements,
was most effective for high growth of N. oceanica. The main nitrogen source in the agricultural fertilizers was ammonium, which was unsuitable for the growth of N. oceanica. Thus, the fertilizer at a lower concentration infused with
as a nitrogen source was more effective than fertilizer at higher concentrations. In this study, the growth of N. oceanica cultured with an agricultural fertilizer medium composed of compound fertilizer (41.7 mg/L), urea fertilizer (34.4 mg/L),
(150 mg/L), and
(0.0588 mg/L) was similar to that of N. oceanica cultured in f/2 medium.
Selection of Suitable Species of Chlorella, Nannochloris, and Nannochloropsis in High- and Low-Temperature Seasons for Mass Culture of the Rotifer Brachionus plicatilis
Bae, Jean-Hee ; Hur, Sung-Bum ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 323~332
DOI : 10.5657/FAS.2011.0323
To find seasonally optimal microalgae for mass culture of the rotifer Brachionus plicatilis, the growth rates of 12 microalgal species (two marine Chlorella spp., five marine Nannochloris spp., two marine Nannochloropsis spp., one estuarine Nannochloropsis sp., and two estuarine Chlorella spp.) were compared at
at 15 psu and 30 psu. Among these, six species showing high growth rates were chosen and examined again at high (
) and low (
) temperatures. Their amino and fatty acids and the dietary value of the rotifers that fed on each microalgal species were examined. Nannochloris sp. (KMMCC-119) and Chlorella vulgaris (KMMCC-120) showed the highest growth rates at temperatures over
, respectively. The growth rate of Nannochloris was higher than those of Chlorella and Nannochloropsis at high temperatures, but lower than those of the latter at low temperatures. The growth rate of rotifers fed on Nannochloropsis was highest and that of those fed on Chlorella was lowest. Levels of eicosapentaenoic acid and docosahexaenoic acid were highest in Nannochloropsis and lowest in Nannochloris. However, total amino acid content was highest in Nannochloris and lowest in Chlorella. In conclusion, Nannochloropsis sp. (KMMCC-33) was the best microalgal species for the mass culture of the rotifer. However, during high- or low-temperature seasons in which Nannochloropsis does not grow well, Nannochloris spp. (KMMCC-119, 395) and C. vulgaris (KMMCC-120) would adequately replace Nannochloropsis sp. (KMMCC-33).
Characterization of a Unique New Strain Named the NFRDI N°1 Rotifer Strain, a Brackish Brachionus Rotifer Collected from a South Korea Coastal Lagoon
Jung, Min-Min ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 333~337
DOI : 10.5657/FAS.2011.0333
A new and a unique Brachionus rotifer was found in Hwajinpo coastal lagoon in Gangwon Province, South Korea. This Brachionus certainly originated from the wild rather than from aquaculture stations because Hwajinpo coastal lagoon has been under rigorous control as a military protected area and therefore could not have been contaminated by aquaculture stations. The new strain was identified as Brachionus rotundiformis based upon its morphological characteristics. The parthenogenetic female of this new rotifer strain typically shows characters similar to those of B. rotundiformis, such as the pot shape of the body, rounded dorsal plate compared with flattened ventral plate, elliptical mictic egg, four frontal spines, six pointed occipital spines, non-nodal foot, two toes, trophi typical of the Brachionus genus with five uncus plates resembling comb teeth, one wide symmetrical manubrium and ramus, and no stiffened spine as is seen in freshwater Brachionus rotifers. Moreover, its lorica was rather small in size compared with other common rotifer strains that serve as live-food organisms (Guam, Thai, and Bali strains). This new and unique Korean brackish rotifer, a B. rotundiformis strain, was therefore named the National Fisheries Research and Development Institute (NFRDI)
Effects of Microalgal Species on the Settlement and Survival of Haliotis discus hannai Larvae
Ko, Su-Keun ; Hur, Sung-Bum ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 339~345
DOI : 10.5657/FAS.2011.0339
Although culture techniques for the abalone Haliotis discus hannai are well known, mass culture of the benthic microalgae that are essential live food for the abalone larvae is still not practiced. This study was conducted to identify the microalgal species suitable for the growth of early larvae of H. discus hannai. The growth and attachment rates of 31 microalgal species were examined. Acrylic plates were used as the substrate. Among the 31 microalgal species, nine showing high growth and attachment rates were selected and tested for their dietary values via factors including settlement, metamorphosis, and survival rates of abalone larvae. Tetraselmis hazeni and Rhaphoneis sp. induced the highest settlement rate (65-69%) in abalone larvae. The metamorphosis rate was highest (57%) in larvae fed Rhaphoneis sp. and was also significantly higher in larvae fed Oscillatoria splendida (29%) and T. hazeni (22%) than in those fed other species. The highest survival rate of the larvae during the 15 days after metamorphosis was 67% in those fed Rhaphoneis sp., followed by T. hazeni (42%) and O. splendida (35%). In conclusion, Rhaphoneis sp. is the most suitable diatom for use as a live food for the culture of early larvae of H. discus hannai. In addition, T. hazeni and O. splendida are also potential species to be further developed and utilized in larval culture.
Prevalence and Characterization of Typical Aeromonas salmonicida Chum Salmon Isolates in Korea
Kim, Yong-Seok ; Yoon, Jang-Won ; Han, Hyun-Ja ; Suebsing, Rungkarn ; Kim, Jeong-Ho ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 347~354
DOI : 10.5657/FAS.2011.0347
Aeromonas salmonicida is an important fish pathogen commonly associated with furunculosis in salmonids. Typical A. salmonicida strains have the surface virulence A-layer protein, a major virulence determinant encoded by the vapA gene. In this study, 880 chum salmon Oncorhynchus keta were collected from the east coast of Korea during 2006-2011, including 560 wild adults and 320 artificially hatched fry pools, and the presence of typical A. salmonicida was examined by PCR using the typical A. salmonicida-specific vapA gene primers. The results demonstrated that 34.5% of the samples (304/880 samples) were PCR positive, implying that a typical A. salmonicida infection is highly prevalent among chum salmon in Korea. Twenty typical A. salmonicida isolates were recovered based on their brown pigmentation on Trypticase Soy Agar (TSA) plates, which indicates the existence of the A-layer protein. Further biochemical analyses with the four randomly selected typical A. salmonicida isolates revealed some variations in their amino acid decarboxylation and carbohydrate fermentation activity. A phylogenetic analysis based on the entire vapA gene sequence suggested that the A. salmonicida isolates from chum salmon were clustered with those isolated from Atlantic salmon in Europe. Further study is needed to resolve such an interesting relationship in detail.
Aluminum Inhibits Vitellogenin Production via Toxic Effects on Hepatocytes in the Rockfish Sebastes schlegelii
Hwang, Un-Ki ; Kang, Han-Seung ; Lee, Yoon ; Shon, Jae-Kyoung ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 355~361
DOI : 10.5657/FAS.2011.0355
Effects of aluminum (Al) on plasma vitellogenin (VTG), alkaline-labile phosphorus (ALPP), calcium (Ca), glutamate pyruvate transaminase (GPT), the hepatosomatic index (HSI), and hepatic Al concentration were examined in estradiol-
)-administered immature rockfish Sebastes schlegeli. Fish were injected intraperitoneally with
(5 mg/kg body weight [BW]) and/or Al (0, 0.1, 1, 5, and 10 mg/kg BW) and plasma and liver samples were extracted 7 days later. After sodium dodecyl sulfate polyacrylamide gel electrophoresis, the relative amount of VTG was determined by integrated optical density. VTG accounted for 23.6% of the total proteins in the control group, but this value decreased with increasing Al administration. Al reduced the concentrations of ALPP and Ca in a concentration-dependent manner and significant reduction occurred at Al concentrations greater than 5 mg/kg. The concentration of GPT increased in a concentration-dependent manner in all Al-administered rockfish. The concentrations of Al in the liver also increased, and HSI was decreased, in a concentration-dependent manner. These results suggest that Al inhibits
-induced VTG production by being toxic to hepatocytes in marine fish.
Comparison of the Nitrification Efficiencies of Three Biofilter Media in a Freshwater System
Harwanto, Dicky ; Oh, Sung-Yong ; Jo, Jae-Yoon ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 363~369
DOI : 10.5657/FAS.2011.0363
Total ammonia nitrogen (TAN) removal efficiencies of a sand filter (SF), polystyrene microbead filter (PF), and Kaldnes bead filter (KF) media were evaluated under ammonia loading rates of 5, 25, and 50 g
. The volume of each filter media tested was 7 L, and the water flow rate for all filter media was 24 L/min. The specific surface areas of the SF, PF, and KF were 7,836, 3,287, and 500
, respectively. Sand was fluidized and the other two media were trickle filtered. The volumetric TAN removal rate increased with increasing ammonia loading rate for all filter media. Mean volumetric TAN removal rates under the ammonia loading rates of 5, 25, and 50 g
in SF (39.3, 168.6, and 322.7 g
, respectively) were higher than those in PF (35.0, 157.4, and 310.5 g
, respectively) and KF (32.1, 142.5, and 288.1 g
, respectively). These results were related to differences in the specific surface areas of the filter media. PF was the most economic media for efficiently removing TAN.
Performance of Three Different Biofilter Media in Laboratory-Scale Recirculating Systems for Red Seabream Pagrus major Culture
Harwanto, Dicky ; Oh, Sung-Yong ; Park, Heung-Sik ; Jo, Jae-Yoon ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 371~378
DOI : 10.5657/FAS.2011.0371
Juvenile red seabream (mean body weight 29.0 g) were reared in recirculating culture systems with three different biofilter media, sand (SF), polystyrene microbeads (PF), and Kaldnes beads (KF). The efficiencies of the three different biofilter media were also tested. The SF was fluidized, and the PF and KF were trickled. All treatments were duplicated. The volumetric removal rates of total ammonia nitrogen by SF, PF, and KF were 193.8, 183.9, and 142.6 g
, respectively, and those of nitrite nitrogen (
-N) were 113.4, 105.9, and 85.8 g
, respectively. The TAN and
-N removal rates of KF were lower than those of SF and PF (P < 0.05), but there was no significant difference in these rates between SF and PF (P > 0.05). Among the biofilters used, only KF showed total suspended solid (TSS) removal capacity. The TSS removal efficiencies of SF and PF were negative. The growth rates of fish in SF were significantly higher than those in KF but not higher than those in PF. There was no difference in growth rate between fish in PF and KF. The specific growth rate and feed conversion efficiency of red seabreams in KF were lower than those in SF and PF, but there were no significant differences between SF and PF. These results indicate that sand and polystyrene microbeads are recommended for red seabream culture in a recirculating system.
The Control Mechanism of Gonadotropin-Releasing Hormone and Dopamine on Gonadotropin Release from Cultured Pituitary Cells of Rainbow Trout Oncorhynchus mykiss at Different Reproductive Stages
Kim, Dae-Jung ; Suzuki, Yuzuru ; Aida, Katsumi ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 379~388
DOI : 10.5657/FAS.2011.0379
The mechanism by which gonadotropin-releasing hormone (GnRH) and dopamine (DA) control gonadotropin (GTH) release was studied in male and female rainbow trout using cultured pituitary cells obtained at different reproductive stages. The mechanisms of follicle-stimulating hormone (FSH) release by GnRH and DA could not be determined yet. However, basal and salmon-type GnRH (sGnRH)- or chicken-II-type GnRH (cGnRH-II)- induced luteinizing hormone (LH) release increased with gonadal maturation in both sexes. LH release activity was higher after sGnRH stimulation than cGnRH-II stimulation at maturing stages in both sexes. The GnRH antagonist ([Ac-3, 4-dehydro-
] GnRH) suppressed LH release by sGnRH stimulation in a dose-dependent manner, although the effect was weak in maturing fish. The role of DA as a GTH-release inhibitory factor differs during the reproductive cycle: the inhibition of sGnRH-stimulated LH release by DA was stronger in immature fish than in maturing, ovulating, or spermiated fish. DA did not completely inhibit sGnRH-stimulated LH release, and DA alone did not alter basal LH release. Relatively high doses (
) of domperidone (DOM, a DA D2 antagonist) increased LH release, which did not change with reproductive stage in either sex. The potency of DOM to enhance sGnRH-stimulated LH release was higher in maturing and ovulated fish than in immature fish. These data suggest that LH release from the pituitary gland is controlled by dual neuroendocrine mechanisms by GnRH and DA in rainbow trout, as has been reported in other teleosts. The mechanism of control of FSH release, however, remains unknown.
Macroalgal Community Structure on the Rocky Shores of Ongdo, Jusamdo, and Woejodo Islands of the Yellow Sea, Korea
Heo, Jin-Suk ; Park, Seo-Kyoung ; Yoo, Hyun-Il ; Song, Ji-Na ; Kim, Bo-Yeon ; Choi, Han-Gil ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 389~397
DOI : 10.5657/FAS.2011.0389
The benthic algal community structures of the seaweed biomass, vertical distribution of dominant seaweeds, and species composition were examined on the rocky shores of Ongdo, Jusamdo, and Woejodo Islands, Korea, in August 2006. A total of 68 seaweeds were identified, comprising 5 green, 11 brown, and 52 red algae from the three study sites. The number of species at Ongdo (32 species) was less than that at Jusamdo (45 species) and Woejodo (44 species). Jusamdo exhibited the maximum seaweed biomass (73.99 g dry
), while the minimum value was found at Woejodo (36.90 g dry
). On the three islands, coarsely branched forms were the most dominant functional group in terms of species number and biomass among benthic algal species. The dominant species were Gelidium amansii, Chondrus ocellatus, and Chrysymenia wrightii at Ongdo, Sargasum thunbergii, Ulva pertusa, and Sargassum fusiformis at Jusamdo, and U. pertusa, Undaria pinnatifida, and Corallina pilulifera at Woejodo. Perennial seaweeds were abundant at Ongdo (G. amansii and C. ocellatus) and Jusamdo (S. thunbergii and S. fusiformis), whereas the sheet form of U. pertusa was relatively abundant at Woejodo Island.
A New Record of Pandalid Shrimp Procletes levicarina (Crustacea: Decapoda: Caridea) from Korean Waters
Kim, Jung-Nyun ; Choi, Jung-Hwa ; Oh, Taeg-Yun ; Choi, Kwang-Ho ; Lee, Dong-Woo ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 399~401
DOI : 10.5657/FAS.2011.0399
The pandalid shrimp Procletes levicarina (Bate, 1888) was newly collected from the western and southern waters of Jeju Island, Korea. This species is the only known member of the genus Procletes which belongs to the family Pandalidae. Morphological description and illustration with a color photograph of the species are given. With the addition of P. levicarina, the family Pandalidae in Korean waters consists of 10 species belonging to 5 genera.
Sexual Maturity and Early Life History of the Mudskipper Scartelaos gigas (Pisces, Gobiidae): Implications for Conservation
Kim, Jin-Koo ; Baek, Hea-Ja ; Kim, Jae-Won ; Chang, Dae-Soo ; Kim, Joo-Il ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 403~410
DOI : 10.5657/FAS.2011.0403
Scartelaos gigas is an amphibious mudskipper species that inhabits mud flats in Korea, China, and Taiwan. This fish is at risk of extinction because of its very restricted habitat and overexploitation. Information about this fish's reproductive characteristics is needed for species conservation. The sexual maturity and early life history of S. gigas were investigated through histological methods and direct observation of eggs in the wild, respectively. In total, 560 individuals of S. gigas were collected with the aid of fishermen from March 2003 to October 2003 at Jung-do Island, southwest Korea. Through microscopic observations of gonadal development, it was determined that S. gigas of both sexes were immature in April, but began to reach maturity in May, and were then fully mature by June, which was maintained until July. In August, some female fish developed early oocytes, but by September oocytes were observed to have degenerated and had been absorbed. Spawned eggs were elliptical and had an average size of 1.37 mm (long axis) by 0.69 mm (short axis). The newly hatched larvae (3.03 mm total length, TL) had an open mouth and anus, two melanophores near the anus, and one large melanophore between the 18th and 19th myomeres. The larvae (3.18 mm TL) showed absorption of the yolk and oil globule within 5 days after hatching and became prelarvae. This species should be considered vulnerable or conservation-dependent, and thus parental fish need to be protected from fishermen during the main spawning season (June).
Food Effect on the Diel Variations and Starvation of the Melania Snail Semisulcospira gottschei Using RNA/DNA Ratios
Kim, Dae-Hee ; Baek, Jae-Min ; Lee, Jong-Ha ; Kim, Bong-Rae ; Yoon, Soon-Jae ; Kim, Jin-Hyoung ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 411~416
DOI : 10.5657/FAS.2011.0411
We investigated the nutritional status of the melania snail (Semisulcospira gottschei) using RNA/DNA ratios to evaluate the effect of feeding conditions (artificial versus natural) on the reaction times of the snails in a time course following starvation. In the short experiments (48 h), the RNA/DNA ratios of the artificial feeding groups were significantly higher than those of the natural groups. While two RNA/DNA ratio peaks were observed in the artificial food group during daytime, the natural food group showed a higher ratio at night. Under starvation conditions, the RNA content decreased whereas the DNA content was constant. The RNA/DNA ratios of the freshwater snail in both groups dramatically decreased after starvation and remained constant until the end of the experiment. We verified that the RNA/DNA ratio serves as an index of nutritional condition with respect to the effect of dietary differences. These results are important for understanding optimized aquaculture rearing conditions for this important commercial freshwater snail.
Effects of pH on Fertilization and the Hatching Rates of Far Eastern Catfish Silurus asotus
Gao, Yang ; Kim, Sun-Gyu ; Lee, Jeong-Yeol ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 417~420
DOI : 10.5657/FAS.2011.0417
In this experiment, we examined the survival, fertilization, hatching times, and hatching rates of Far Eastern catfish Silurus asotus at pH ranging from 2 to 13 under laboratory conditions. Eggs could be fertilized at pH 3-12. In a hatching experiment, mortality was first observed at pH 13, when all fertilized eggs died within 8 min, followed by pH 2 (30 min), pH 12 (60 min), pH 3 (4 h), and pH 11 (5 h). Hatching only occurred at pH 4-10, with the highest hatching rate at pH 7 (52%) and the lowest at pH 10 (24%). Hatching rates in acid solutions were higher than in alkaline solutions, although the difference was not significant. Hatching was first observed at pH 10, beginning 27 h after fertilization and ending at the 31 h. A clear difference was observed between hatching times, ranging from 31 to 64 h and increasing in order with descending pH.
Seawater Exchange and Residence Time in Gamak Bay Determined by Numerical Experiments
Lee, Moon-Ock ; Kim, Byeong-Kuk ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 421~428
DOI : 10.5657/FAS.2011.0421
We conducted modeling experiments to evaluate the residence times and exchange rates of seawater in Gamak Bay, located on the southern coast of the Korean Peninsula. The results revealed that pollutants are more quickly dispersed in a fixed grid rather than in a variable grid system. Pollutant concentrations decayed exponentially with time after release near the mouth of the bay, whereas no exponential variations were seen at the northwest end of the bay. The mean exchange rate of the seawater was 1.58% per day in the variable grid system, and the residence time of pollutants was greater than 288 days in Gamak Bay. Conversely, the exchange rate of seawater in Gamak Bay, as revealed by the particle tracking method, was 65% over a 50-day simulation. The results suggest that the seawater exchange in Gamak Bay is so low that pollutants are likely to remain in the bay indefinitely.
Temperature-dependent Index of Mitotic Interval (τ
) for Chromosome Manipulation in Korean Rose Bitterling Rhodeus uyekii
Kim, Bong-Seok ; Lim, Sang-Gu ; Gil, Hyun-Woo ; Park, In-Seok ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 429~433
DOI : 10.5657/FAS.2011.0429
Eggs of Korean rose bitterling Rhodeus uyekii were collected and fertilized to observe temperature-related cleavage rates and mitotic intervals (
). As the water temperature was increased, the slope of first cleavage frequency with elapsed time after fertilization increased, and approximately 30% of fertilized eggs reached first cleavage frequency at every 15 min. At higher temperatures, eggs developed faster and underwent further identical developmental processes. There were strong, negative correlations between
and water temperatures at all temperatures studied (Y = -1.225X + 70.05,
, where Y is
and X is temperature).
Feeding Habits of Yellow Goose Fish Lophius litulon and John Dory Zeus faber in the South Sea of Korea
Choi, Jung-Hwa ; Sung, Bong-Jun ; Lee, Dong-Woo ; Kim, Jong-Bin ; Oh, Taeck-Yun ; Kim, Jung-Nyun ;
Fisheries and aquatic sciences, volume 14, issue 4, 2011, Pages 435~441
DOI : 10.5657/FAS.2011.0435
The feeding habits of yellow goosefish Lophius litulon and John Dory Zeus faber were studied by analyzing the stomach contents of specimens collected in the South Sea of Korea. In total, 132 hauls were taken during six experimental trawl survey (Tamgu 1) cruises conducted on a seasonal basis (March 2005-October 2007). The main prey items of the two species were similar. Fishes and crustaceans were the most important prey, with neither species showing ontogenetic changes in preferred species. Specifically, Pennahia argentata was the preferred prey item of L. litulon, whereas Trichiurus lepturus and Engraulis japonicus were preferred by Z. faber. Larger Z. faber (>24 cm) preferred bigger prey such as T. lepturus and Larimichthys polyactis, while smaller Z. faber preferred E. japonicus and Acropoma japonicum.