• Journal of Aquaculture
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• v.17 no.3
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• pp.167-172
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• 2004

Chemoenzymatic method was used in this study to evaluate the quality of cultured red seabrim. Level of ATP related compounds, ATPase and Adenylate energy charge (AEC) well reflected changes in condition of fish. ATP level in the muscle of exercised cultured red seabream was decreased significantly during cultured period. In contrast, the level of ADP in the muscle was increased during the period. Level of ATP related compounds in the muscle of cultured red seabream without exercise didn't show significant difference compared to the exercised group. AEC value in muscle of cultured red seabream without exercise was 0.89$\pm$0.02, while AEC value of the exercised group was 0.88$\pm$0.04. ATP and AEC levels among different size of fish did not show any significant difference. AEC value in all sample was higher than 0.8, indicating that the condition of cultured fish was healthy. Activity of Mg2$^{＋}$ (＋Ca2$^{＋}$), Mg2$^{＋}$ (-Ca2$^{＋}$) and Ca2$^{＋}$-ATPase during culture period did not change significantly, regardless of exercise. Therefore, the AEC appears to have some validity as fish health indicator.

• Development and Reproduction
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• v.23 no.1
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• pp.35-42
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• 2019

Fish shows great difference in growth rate between individuals during larval development and early growth. This difference seriously reduces the production efficiency in fish culture. Growth hormone (GH)/Insulin-like growth factor 1 (IGF1) system is said to play some pivotal roles in fish growth. In this study, we investigated differences of GH, IGF1 and GHR gene expressions in juvenile red spotted grouper (Epinephelus akaara) with different growth performance. Red spotted groupers were reared under the same environmental condition (water temperature $24{\pm}1^{\circ}C$, natural light) for 96 days after hatching. They were divided into 3 groups by size (fast growing, middle growing and slow growing groups: FGG, MGG, and SGG, respectively). RNA was extracted from the brain, liver and muscle tissues from each group, and target gene expression was examined by real-time PCR. In the brain with pituitary gland, expression of GH gene in FGG was significantly higher than the expression in SGG, but the expression of IGF1 and GHR genes in the muscle was highest in SGG. Difference of GHR and IGF1 mRNA in the liver between groups with different growth performance was less clear than that in other tissues, although level of IGF1 mRNA was higher in SGG than in MGG. These results suggest that hormonal governing of growth is not the same in fast growing and slow growing fish, and size grading could cause a shift of hormonal state and growth pattern in this species.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1148-1153
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• 2008

For the effective use of red seabream, the texture between red seabream muscles cultured by feeding and starving were compared. Moisture and crude lipid contents of red seabream muscle cultured by starving (RCS) were 72.7% and 3.7%, respectively, which was 3% higher in the moisture compared to that of red seabream muscle cultured by feeding (RCF), while 3% lower in the crude lipid. The hardness of RCS was $0.93\;kg/cm^2$, which was higher than that ($0.47\;kg/cm^2$) of RCF. No differences in total collagen content, acetic acid-solublized collagen content, its thermal denaturation temperature and SDS-PAGE patterns between RCS and RCF were found. The results suggested that the difference in muscle texture between RCS and RCF was probably due to the difference of lipid content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.6-11
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• 2010

Chub and blue mackerels are popular fish resources in Korea, but little is known about each biochemical characters of different anatomical regions. To investigate biochemical characters of chub and blue mackerels, three ordinary muscle regions were identified by their fin position; namely anterior, median, posterior. In addition, red muscle, as a dark muscle, was obtained from beneath the lateral line to compare with ordinary muscles. Proximate and lipid-class compositions did not show any discernible trends in the different anatomical ordinary muscles from mackerel of the same kind, while significant differences between ordinary and red muscles in the same mackerel, or between chub and blue mackerels, were observed. Red muscles from both mackerels had higher levels in lipids with higher neutral lipid class compared with ordinary muscles. The major difference between chub and blue mackerels was the levels of lipids and neural lipid class, indicating that all muscles from chub mackerel showed higher levels of neural lipids compared with those of blue mackerel (P<0.05). Fatty acid compositions showed that the percentage of polyunsaturated fatty acids (PUFA), especially docosahexaenoic acid (DHA, 22:6n-3), in median and posterior was higher compared with anterior muscle from both mackerels. When compared with chub mackerel, blue mackerel showed higher percentage of DHA in all muscle regions. In amino acid analysis, taurine concentration was much higher in the red muscle than in the ordinary muscles. But levels of histamine, glutamic acid, leucine and lysine were higher in the ordinary muscles. Our results indicated that chub mackerel contained more lipids than blue mackerel and that red muscle had higher levels of neural lipid and taurine compared to ordinary muscles.

• Environmental Mutagens and Carcinogens
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• v.15 no.2
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• pp.115-121
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• 1995

Bacterial mutagenicity of shellfish or canned products of red-muscle fish affected by hot-airdry processings and/or during storages was investigated by Ames preincubation method. Mussel (Mytilus edulis) and surf clam (Tapes japonica) dried under either 40$\circ$C, 50$\circ$C or 60$\circ$C until remained about 25 % water content was stored at 4$\circ$C or 25$\circ$C for 6 months. Commercially available canned product of pacific saury (Cololabis saira) and mackerel saury (Scotnberjaponicus), whose producer or date of manufacture was identical each other, was stored at 25$\circ$C for 6 months. Mutagenic substances from sample (25 g dry weight) were extracted and purified for mutagenicity assay against S. typhitnurium TA98 by the simultaneous distillation extraction (SDE) method (Lee et al. 1955). Mutagenicity of sample was expressed number of revertant per 25 g dry sample. Number of revertant from unheated mussel sample was appeared to be 135, relative to 22 from unheated surf clam sample. Mutagenicity of both shellfish was strongly affected by heat treatment, but a lesser extent by storage conditions, even at 25$\circ$C for 6 months. Revertants of the mussel sample dried at 40$\circ$C, 50$\circ$C, or 60$\circ$C was found to be 227, 779, and 883, respectively. Similar, but lower, mutagenicity was observed from the sample of surf clam dried at 40$\circ$C, 50$\circ$C, or 60$\circ$C than mussel. Mutagenicity of canned pacific saury and mackerel samples was not influenced by storage conditions. Number of revertant from pacific saury was 175 which was relatively higher than 5 from mackerel. Mutagenicity of fresh pacific saury and mackerel samples was significantly higher than that of their counterparts from canned products. These results indicate that mutagenicity of the shellfish was affected by heat treatment (40$\circ$C, 50$\circ$C, or 60$\circ$C) used for drying process, but not much by storage for 6 months at 4$\circ$C or 25$\circ$C and the mutagenicity of canned products of red-muscle fish was not influenced by storage, even at 25$\circ$C for 6 months.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.199-204
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• 1995

The changes of nucleotide and their related compounds, TMAO, TMA and total creatinine content of mackerel, pacific saury, yellow croaker and brown sole were investigated on heating conditions. The results were as follows. The content of inosine was the highest in all fish commonly, and white muscle fish showed higher than that of red muscle fish. The content of hypoxanthine showed increase by heat treatment but other compounds showed decrease. The contents of TMAO showed 31.1, 26.2, 49.4 and 58.5 mg% in each sample of raw materials, and brown sole showed the highest content than other fishes and TMAO contents showed decrease by heat treatment. The contents of TMA showed 3.7, 5.8, 22.9 and 16.9 mg% in each sample, and pacific saury showed the highest content than other fishes but TMA contents showed increase by heat treatment. The contents of total creatinine showed 341.2, 469.8, 52.3 and 87.6 mg% in each sample, and red muscle fish showed higher than that of white muscle fish and the highest content was shown in yellow croaker. All fish species showed decrease in contents of flavoring by heat treatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.929-935
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• 1997

The total energy of fish movement and the maximum burst swimming speed were estimated and formulated in accordance with body length and water temperature for several species in fisheries by empirical methods and also by using published results. Under the assumption of swimming energy reserve of a fish at the initial rest state, the swimming endurance of fish with different body lengths, swimming speeds and angular velocity was calculated using the relevant equations under similar conditions in tank experiments as well as natural conditions in field. Relative swimming energy efficiency or the transition swimming speed between red and white muscle for energy consumption was represented as a trigonometric function of swimming speed ratio. Therefore, this model does closely approach the actual swimming abilities and their limits especially in relation to the fishing gear operation and allow for the greater vitality of the wild fish in the fields.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.361-367
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• 1996

As a part of investigation for quality improvement of surimi gel from fish with a red muscle by addition of emulsion curd, we investigated the processing conditions of emulsion curd contained succinylated gelatin from conger eel skin as an emulsifier and emulsion curd-added surimi gel. Activity and stability of emulsion curd on standing at room temperature, chilled temperature and vibration were remarkably improved by the addition of 15 tunes of soybean oil and 5 times of water to succinylated gelatin from conger eel skin. The proximate composition of the emulsion curd was moisture 18%, protein 5%, lipid 76% and ash 0.5% and its appearance was white. Peroxide value and fatty acid composition of emulsion curd contained succinylated gelatin as an emulsifier were similar to these of soybean oil. By the addition of 6% of emulsion curd to mackerel surimi, gel strength, appearance and texture of the resulting surimi gel were improved, while its peroxide value and brown pigment revealed minor change. From the results of volatile basic nitrogen, viable cell counts and histamine content, the emulsion curd-added mackerel surimi gel can be safe In the sense of food sanitation.

• Preventive Nutrition and Food Science
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• v.22 no.2
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• pp.90-99
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• 2017

Fish muscles are classified into white and red muscles, and the chemical composition of the two fish muscles have many differences. Few reports have assessed the health-promoting functions of white fish muscle proteins (WFP) and red fish muscle proteins (RFP). We therefore evaluated the mechanisms underlying the alteration of lipid profiles and cholesterol metabolism following the intake of WFP prepared from cod and RFP prepared from light muscles of tuna. Male Wistar rats were divided into six dietary groups: casein (23%), WFP (23%), and RFP (23%), with or without 0.5% cholesterol and 0.1% sodium cholate. Compared to the WFP-containing diet, the RFP-containing diet supplemented with cholesterol and sodium cholate significantly increased serum and liver cholesterol contents. However, in the RFP groups, an alteration in cholesterol metabolism including an increased tendency to excrete fecal sterols and hepatic cholesterol $7{\alpha}$-hydroxylase was related to the reduction of hepatic cholesterol contents. This phenomenon might be related to the tendency of an increased food intake in RFP-containing diets. These results highlight the differential effects of WFP and RFP on serum and liver lipid profiles of Wistar rats fed non-cholesterol- or cholesterol-containing diets under no fasting condition.

• Journal of fish pathology
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• v.19 no.2
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• pp.155-164
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• 2006

Tissue distribution and residue depletion of oxytetracycline (OTC) and tetracycline (TC) following dipping administration were evaluated in olive flounder (Paralichthys olivaceus), rockfish (Sebastes schlegeli), and red sea bream (Pagrus major) under field conditions. Fishes were held in floating cages placed in sea water and fed a commercial diet for 15 days to acclimate to a new surrounding. Fishes were dipped in OTC 50 g/ton water for 30min and TC 18 g/ton water for 5 hours. Blood and muscle were sampled from fishes on 0th, 1th, 2th, 3th, and 5th day after administration. After solid-phase extraction, OTC and TC analyses were carried out by HPLC. The recovery rate of OTC in serum and muscle samples was 71-77% and 78-84%, respectively. Also, the recovery rate of TC in serum and muscle samples was 70-79% and 73-78%, respectively. The results of recovery rate were similar to previous studies reported. At the termination of dipping administration of OTC and TC, residue concentration in muscle samples of rockfish was significantly higher than those of olive flounder and red sea bream. At day 5, residue concentrations of all samples were believed to decrease to lower than 0.05 mg/kg, the detection limit. The present study showed that residue concentrations of OTC and TC decreased to below 0.05 mg/kg after treatment 5th day, faster than the established withdrawal period. The tissue reside depletion time of dipping administration of OTC and TC seems to be shorter than those of oral or parenteral administration.