• Korean Journal of Ichthyology
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• v.33 no.2
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• pp.95-106
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• 2021

In order to understand the seasonal variations of species composition of fish in the Goseong, middle East Sea of Korea, we surveyed fish fauna using set net during 2 years. In this study, a total of 77 taxa belonging to 40 families were collected and 75 species were identified. The dominant family were Tetraodontidae and Pleuronectidae, and the dominant species were Arctoscopus japonicus, Konosirus punctatus, Stephanolepis cirrhifer, Thamnaconus modestus, and Trachurus japonicus. The results of the hierarchical clustering using the number of individuals of collected species showed that they are divided into three seasonal groups: Group A (Jan.~Apr.), Group B (May~Jun., Nov.~Dec.), Group C (Jul.~Oct.). The sea surface temperature (SST) was higher than the results of previous studies in winter and spring, and species composition in spring have changed from cold-water species to the warm-water species, recently. The species composition has become similar to the that of southern Gangwon-do regions (Samcheok and Gangneung) of the previous studies. The species diversity of family Tetraodontidae has increased, which is estimated to have an effect on increase in SST and the quantity of entering the East Sea. Therefore, we assumed that the change of species composition is related to the extension of northern distribution limits and survival temperature, and abundant preys. Therefore, it is necessary that an efficient resource management policy as well as the ways of commercially use of migratory warm-water fish, rapidly.

• Korean Journal of Environmental Biology
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• v.33 no.1
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• pp.27-33
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• 2015

Fish assemblages in the coastal waters off Gampo in the East Sea of Korea were analyzed using the samples of fishes collected with bottom trammel gill nets June, September, and December 2005 and, March 2006. During the study period, a total of 32 fish species, 695 individuals, and 180,012.0 g representing 21 families were collected. The fish assemblages predominantly consisted of Ditrema temminckii, which accounted for 52.4% of the number of individuals and 40.4% in the biomass. The next major specimens were Hexagrammos otakii, Sebastes schlegelii, Stephanolepis cirrhifer, Sebastes taczanowskii, Halichoeres poecilopterus. These six fishes accounted 77.6% of total number of individuals and 77.5% of total biomass. The number of fish species, the number of individuals and biomass were fluctuated with month. The number of species was highest in June 2005 and lowest in March 2006. The number of individuals and biomass was highest in September 2005 and lowest in June 2005.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.159-172
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• 1993

Collagenase existed in the internal organs of filefish Novoden modestrus was isolated with ammonium sulfate and was purified by ion exchange column chromatography with DEAE-Sephadex A-50 and gel filtration with Sephadex G-150. The activity of the purified enzyme was increased 92.4 folds than that of the crude one and the yield of the purified one was $10.9\%$. The optimum conditions showing the maximum activity of the crude enzyme to digest insoluble collagen(Type I) were $55^{\circ}C$ and pH 8.0, while those showing the maximum activity of the purified one were $55^{\circ}C$ and pH 7.75. However, the use of the crude enzyme for skinning of filefish was more profitable because the yield was 800 folds higher than that of the purified one and the cost was also able to economy. When hydrolysis for skinning of filefish was conducted with $0.3\%$(w/w) crude collagenase at $50^{\circ}C$ and pH 8.0 for 3hrs, there was some problem to cause a damage on muscle of the fish by heat. To solve such problem for the skinning, the hydrolysis at $18^{\circ}C$ for 4hrs with $0.3\%$ (w/w) crude enzyme after pretreated with 0.5M acetic acid for 10 min provided a good result for skinning of filefish.

• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.179-185
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• 2010

This is a study of the fish assemblages in eelgrass beds of Geoje Bay on Geoje Island, Korea. Samples were collected by surf net monthly from June 2006 to May 2007. A total 26 species, 1,825 individuals, and 4,483.1 g of fishes were collected. The dominant species were Acentrogobius pflaumii, Aulichthys japonicus, Gymnogobius heptacanthus, Rudarius ercodes, Chaenogobius annularis, Gymnogobius urotaenia, Syngnathus schlegeli, Pterogobius elapoides, Zoarchias glaber, Takifugu niphobles, Zoarchia suchidai. These species accounted for 90.6% of the total number of individuals and 76.2% of the biomass of the fishes collected. The fish assemblages in the eelgrass beds showed clear seasonal changes; the number of fish species and individuals increased in March and were highest in September, whereas the biomass attained its highest level in May and subsequently decreased. Meanwhile the species diversity indices showed their highest value in December.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.27-35
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• 2020

Filefish Thamnaconus modestus has seen a sharp decline in their catch, we must strive for continuous resource management. We investigated the maturation and spawning of T. modestus by trawl net and set net from January 2018 to November 2019, off Jeju Is. and in coastal waters of North Gyeongsang Province's Korea. We analyzed monthly change total length (cm), gonadosomatic index (GSI) and maturity stages, egg diameter (mm), the relations fecundity and total length. GSI for Jeju Is. was the highest in April (3.17, 2.43), and decreased from July to 1.73 in August and GyeongBuk's GSI was the highest in Apri l (1.86, 2.58), followed by the high in May and the sharp decline in September, which is 0.23. Using a histological method, the annual reproductive cycle of T. modestus can be divided into 5stage in females; the early growing stage (Jan.-Mar.), late growing stage (Apr.-May), Mature stage, spent stage (Oct.), Recover and resting stage (Nov.-Jan.).We estimate the TL at 50% maturity as 24.1cm for female, fecundity ranged from 560,044 eggs at 23.4cm total length to 1,580,387 eggs at 36.6.cm TL.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.43-48
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• 1982

Quality of meaty textured fish protein concentrate (MT-FPC) prepared from filefish. Navodon modestus, and sandfish. Arctoscopus japonicus, was investigated. The stability of the product during storage under various conditions was evaluated with rehydration capacity, thiobarbituric acid (TBA) value and browning colour density. MT-FPC packed in glass bottle with air and stored at room temperature showed no significant differences in TBA value, rehydration capacity and browning colour density during the storage period of 90 days. The jelly strength of product prepared from filefish was weaker than that of sandfish: and beef meat could be substituted with MT-FPC up to 50% in making hamburger and fried meat balls without a significant loss in taste, odor and texture.

• Korean Journal of Ichthyology
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• v.28 no.4
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• pp.249-259
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• 2016

Monthly variation in species composition was determined using fish samples collected by a beach seine between October 2013 and September 2014 in the eelgrass bed in Aenggang Bay, Namhae, Gyeongsangnamdo. A total of 3,174 individuals of 35 species, amounting to 3,137 g were collected. The dominant species was Gymnogobius heptacanthus, followed by Pholis nebulosa, Rudarius ercodes, Favonigobius gymnauchen and Hypodytes rubripinnis. Almost all fish collected were small in size or juveniles. Seasonal variation of species composition showed that the dominant species, used the shallow area of the eelgrass bed as a nursery ground and moved to a deeper water as they grew. Saurida elongata, Inimicus japonicus, Sphyraena pinguis, and Arothron hispidus, were first reported in an eelgrass bed in the southern coastal water.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.262-268
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• 1983

Properties of noodle prepared with FPC and wheat flour were investigated, and the results were summarized as follows: 1. Farinogram showed that the water absorption ratio and dough development time increased as the mixing level of FPC to wheat flour increased. 2. Amylogram showed that the maximum viscosity of the composite flour decreased as the content of FPC increased. 3. In the textural parameters, such as hardness, cohesiveness and gumminess of noodles, there were no marked differences between wheat flour and cooked noodles from the composite flour of 3% or 5% FPC-97% or 95% wheat flour. 4. Regarding weight and volume of the cooked noodles, those of cooked noodles from the composite flour of 3% or 5% FPC-97% or 95% wheat flour were similar to wheat flour alone. As the content of FPC in noodle increased, however, those of cooked noodles slightly decreased, and soup turbidity increased. 5. Results of sensory evaluations showed that the noodle from the composite flour of 3% FPC-97 wheat flour appeared to be the most acceptable, and the noodles from the composite flour of 5% or 7% FPC-95% or 93% wheat flour were judged as acceptable as the wheat flour alone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.423-435
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• 1984

The reproductive cycle of the small filefish, Rudarius ercodes was investigated based on the annual variations of gonadosomatic index(GSI) and hepatosomatic index(HSI) by electronic and photic microscophy. The specimens used were collected at the coastal area of Benden island, Sizuokagen, Japan, from September 1982 to August 1983. GSI began to increase from March, starting season of longer daylength and higher water temperature, and reached the maximum value between June and August. It began to decrease from September with the lowest value appearing between November and February without any evident variation. The annual variations of HSI were not distinct in male filefish and were negatively related to GSI in female : HSI decreased in the summer season when the ovary was getting mature and reached the maximum in the winter season when the ovary was getting retrogressive. The ovary consisted of a pair of saccular structure with numerous ovarian sacs branched toward the median cavity. Oogonia divided and proliferated along the germinal epithelium of the ovarian sac. Young oocytes with basophile cytoplasm showed several scattering nucleoli along the nuclear membrane. when the oocytes growing to about 300 ${\mu}m$, nuclear membrane to disappear with nucleus migrating toward the animal pole. The regions of protoplasm were extremely confined within the animal hemisphere in which most of cytoplasms were filled with yolk materials and oil drops. After ovulation, residual follicles and growing oocytes remaining in the ovarian sacs degenerated. But perinucleatic young oocytes without follicles formed were not degenerated, and growing continuously still in the next year. Mitochondria and endoplasmic reticula in the cytoplasm remarkably increased with oocytes maturing and yolk accumulating. Those were considered to be functionally related to the yolk accumulation. Five or six layers of possible vitellogenin, oval-shaped disc structures with high electron density, appeared in the apex of follicular processes stretching to the microvilli pits of mature oocytes. Testis consisting of a pair of lobular structures in the right and left were united in the posterior seminal vesicle, Cortex of testis was composed of several seminiferous tubules, and medulla consisting of many sperm ducts connected with tubules. Steroid hormone-secreting cells with numerous endoplasmic reticula and large mitochondria of well developed cristae were recognized in the interstitial cells of the growing testis. Axial filament of spermatozoon invaginated deeply in the central cavity of the nucleus and the head formed U-shape with acrosome severely lacking, mitochondria formed large globular paranuclei at the posterior head, and microtubular axoneme of the tail represented 9+9+2 type. The annual reproductive cycles could be divided into five successive stages : growth(March to July), maturation(May to September), Spawning(mid May to early October) and resting stages(October to February). The spawning peak occurred from June to August.

• Korean Journal of Ichthyology
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• v.33 no.1
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• pp.22-30
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• 2021

This study aimed to determine the monthly fish species composition in the eelgrass bed of Yeocha on Hansando Island, Korea, and to obtain fish species data by comparison with the nearby Bongam. The species composition was determined from monthly samples collected by a surf net from August 2009 to July 2010. During the survey, total 2,394 individuals of 29 species and 10,378 g of fish were collected. The dominant species were Gymnogobius heptacanthus, followed by Takifugu niphobles, Rudarius ercodes, Chaenogobius annularis, and Ditrema temminckii, accounting for 89% of the total individuals sampled and 83% of the fish biomass collected. The fish assemblages in the eelgrass bed varied seasonally; the number of individual fishes increased in May and was highest in July, whereas the biomass attained its highest level in April and subsequently decreased. This study confirms that the seagrass bed plays an important role as a fish nursery ground, and it is necessary to investigate changes in the coastal fishes of the southern coast via periodic surveys.