• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.41-47
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• 1989

Using computer simulated irregular waves, variations of ocean wave statistics according to sea state are analyzed, and the reasonable conditions that transform the energy spectrum to individual wave statistics are discussed. Ocean wave statistics varying with sea state are found to respond linearly to the spectral peakedness parameter $Q_p$ and spectrum moments $m_n$ (n = 0, 1, 2${\cdots}{\cdots}\;\infty$ ). It is clarified that the 2nd-order spectrum moment is a reasonable parameter which represents the wave statistics including wave periods, and that the spectrum analysis should be carried out under the conditions of minimum data length of 10 times of peak period $T_p$ with time lag of $7T_p$ to satisfy the stable condition of wave statistics.

• 한국수산학회:학술대회논문집
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• 2005.05a
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• pp.209-210
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• 2005

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.1
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• pp.68-72
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• 2007

Flounder is one of the major aquacultured fish and of an economically important item in Korean fisheries. Recently, there are trends of research worldwide that aim to analyze and characterize a whole genome or a whole proteome of interesting species. The data are utilized for the understanding and development of preventive and curative technologies for the serious diseases. However, there are very limited information of proteome for marine organisms, we optimized first the conditions for two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) with serum form a marine fish, flounder (Paralichthys olivaceus). A pre-treatment of serum and an optimization of protein concentration analyzed were surveyed for enhancing the separation for proteins. A statistical analysis was performed on the overall 1,820 protein spots to overcome the variability among individual fishes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.470-477
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• 2011

This study reviewed the effect of the drying conditions on the production of biogenic amines and lipid oxidation in semi-dried Pacific saury Cololabis saira or Guamegi. The moisture content of the Guamegi ranged from $32.71{\pm}2.37$ to $45.9{\pm}2.60$ g/100 g. The respective ranges of the acid value (AV) and peroxide value (POV) were $1.39{\pm}0.40$ to $15.79{\pm}0.47$ mg KOH/g and $76.14{\pm}2.19$ to $282.84{\pm}2.34$ meq/kg on drying for 3 days. The AV and POV increased for up to 3 days of drying and the values differed according to the amount of sunlight and temperature. However, lipid oxidation was reduced in Guamegi manufactured using a cold-air drying method. The fatty acid composition and the biogenic amine content in Guamegi during drying did not differ significantly with the drying method or drying date. The main saturated, monoene and polyene fatty acids were palmitic acid, eicosenoic & erucic acids, and eicosapentaenoic & docosahexaenoic acids, respectively. At 16.67 to 71.89 mg/kg, the histamine content was higher than that of other biogenic amines and it increased significantly during drying. In conclusion, this study showed that the packaging and drying conditions of Guamegi products need to be improved to inhibit lipid oxidation and biogenic amine formation.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1996.06a
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• pp.208-210
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• 1996

• Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.335-349
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• 2022

To optimize the hydrolysis conditions in the production of antioxidant hydrolysates from tuna cooking juice concentrate (TC) to maximize the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, TC containing 48.91% protein was hydrolyzed with Alcalase 2.4 L, and response surface methodology (RSM) was applied. The optimum hydrolysis conditions included a 2.2% (w/v) Alcalase concentration and 281 min hydrolysis time, resulting in the highest DPPH radical scavenging activity of 66.49% (0.98 µmol Trolox/mg protein). The analysis of variance for RSM showed that hydrolysis time was an important factor that significantly affected the process (p < 0.05). The effects of different drying methods (freeze drying, hot air drying, and vacuum drying) on the DPPH radical scavenging activity and amino acid (AA) profiles of TC hydrolysate (TCH) were evaluated. Vacuum-dried TCH (VD) exhibited an increase in DPPH radical scavenging activity of 81.28% (1.20 µmol Trolox/mg protein). The VD samples were further fractionated by ultrafiltration. The AA profiles and antioxidant activities in terms of the DPPH radical scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) radical scavenging activity, ferric reducing antioxidant power, and ferrous ion chelating activity were investigated. Glutamic acid, glycine, arginine, and cysteine were the major AAs found in the TCH fractions. The highest DPPH radical scavenging activity was found in the VD-1 fraction (< 5 kDa). The VD-3 fraction (> 10 kDa) exhibited the highest ABTS radical scavenging activity and ferric reducing antioxidant power. The ferrous ion chelating activity was the highest in VD-1 and VD-2 (5 to 10 kDa). In conclusion, this study provided the optimal conditions to obtain high antioxidant activities through TCH production, and these conditions could provide a basis for the future application of TCH as a functional food ingredient.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.4
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• pp.293-297
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• 2010

To prevent amnesic shellfish poisoning (ASP) resulting from the consumption of shellfish contaminated with domoic acid, the quantitative analysis of domoic acid is very important. We validated a high performance liquid chromatography (HPLC) method for accurate and precise quantification of domoic acid. A clear peak and the isolation of domoic acid resulted on injecting a 50% methanol extract of CRM-ASP-Mus-c mussel reference material using HPLC. The limit of detection of domoic acid under the established HPLC conditions was $0.10\;{\mu}g/g$, and the limit of quantification of the toxin under the same conditions was $0.25\;{\mu}g/g$. The intra-accuracy and precision for domoic acid in CRM-ASP-Mus-c were 90.7-95.7% and 0.28-22.25%, respectively. The inter-accuracy and precision for domoic acid were 89.1-97.1% and 1.7-4.1%, respectively. The mean recovery of domoic acid in methanol extracts from ten species of marine invertebrates was 88.6-1105.1%.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.4
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• pp.299-307
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• 2016

This study aims to investigate effects of the length of the buoy and sand bag line on the loss of webfoot octopus pot. A numerical modeling and simulation was carried out to analyze the process that the pot gear affected by wave using the mass spring model. Through the simulation, tensions of sand bag line under various condition were investigated by length of buoy and sand bag line. The drag force and coefficient k of an artificial shell used in the webfoot octopus pot was obtained from an experiment in a circular water channel, and the coefficient k was applied to the simulation. To verify the accuracy of the simulation model, a simple test was conducted into measuring a rope tension of a hanging shell under flow. Then, the test result was compared with the simulation. The lengths of the buoy line in the simulation were 1.12, 1.41, 1.80, 2.23, 2.69, and 3.17 times of water depth. The lengths of sand bag line were 10, 20, 30, and 40 meters, and conditions of water depth were 8, 15, 22 meters. 4 meter height and 8 second period of wave were applied to all simulations. As a results, the tension of the sand bag line was decreased as the buoy and sand bag line were increased. The minimum tension of the sand bag line was appeared in conditions that the length of the buoy line is twice of water depth and the sand bag line length is over 40 meters (except in case of depth 8 meters.).

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.167-174
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• 1989

AS a part of investigation to use anchovy more effectively as food source, this work was undertaken the processing conditions of extracts from rapid fermented anchovy sauce. To prepare rapid fermented products, the chopped anchovy was mixed with 50% water (w/w), and then hydrolyzed by autolysis or addition of koji under different conditions of hydrolysis. The optimal conditions for hydrolysis of chopped anchovy were revealed $50^{\circ}C$, 6 hours, pH 8.0 by autolysis, and ,$50^{\circ}C$, 6 hours, pH 7.0 by addition of 10% koji, respectively. But, pH control was not much beneficial in increasing yield. The effect of soybean protein isolote for improvement of bitter taste was also tested. The reasonable amount of added soybean protein isolate was revealed 5% on the weight basis of the chopped anchovy. The reaction mixture hydrolyzed under optimal conditions were added with 1% onion powder (w/w), 1% garlic powder(w/w) and 1% red pepper powder(w/w) for masking fishy odor, inactivated for 20 min at $100^{\circ}C$, and then centrifuged for 20 min at 4,000 rpm. The supernatant liquor was filtrated and evaporated to 50%(v/v). finally, table salt was added for bateriostatic effect and characteristic taste of rapid fermented products. the reasonable amount of added table salt was reversed 15% on the volume basis of the evaporated liquor. The hydrolysis ratio of product made by addition of water, product made by addition of koji and water, and product made by addition of soybean protein isolate, koji and water hydrolyzed under optimal conditions were 58.4%, 82.1% and 86.2%, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.4
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• pp.298-306
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• 2010

A sanitary survey was conducted to evaluate the water quality and mussel (Mytilus edulis) conditions of two administrative shellfish growing waters: those designated as shellfish growing water for export, and adjacent waters on the east coast of Changseon Island, Namhae, Korea. In all, 1,656 seawater and 166 mussel samples were collected at 46 stations for seawater and five stations for the shellfish from January 2007 to December 2009. Both seawater and mussels were examined for total coliforms and fecal coliforms. The standard plate count and most probable number of Escherichia coli were also determined for the shellfish samples. The range of the geometric means and the estimated 90th percentiles of fecal coliform for seawater samples at each station were <1.8-4.1 MPN/100 mL and <1.8-22.3 MPN/100 mL, respectively. The sanitary conditions for both shellfish growing areas, the designated shellfish growing area and adjacent area in Changseon, met the 'Approved area' criteria of the United States National Shellfish Sanitation Program. The range of E. coli detected in mussels in these areas was <20-500 MPN/100 g; and only 3 of 166 samples exceeded 230 MPN/100 g, the European standard for the consumption of raw bivalves. Therefore, the mussel farms in the Changseon area are classified as 'Class A' according to criteria set in European Community regulations. However, the levels of E. coli in mussels in parts of the designated shellfish growing area and adjacent area exceeded the bacterial limits after rainfall exceeding 45 mm. Further studies are needed to fully define the conditions leading to a temporary closure to harvest after a rainfall event.