• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.279-286
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• 1996

Cultivated tilapia (Oreochromis niloticus) in the fresh water were acclimated to the sea water to improve palatability of the fish meat. Physicochemical properties in the rigor mortis of those fish meats were investigated during storage at $0^{\circ}C,\;10^{\circ}C\;and\;20^{\circ}C$. The faster onset of rigor mortis was occurred in acclimated meat than fresh water cultivated meat. Both meats stored at $0^{\circ}C$ showed faster figro mortis than at $10^{\circ}C\;and\;20^{\circ}C$. Significant difference was not observed between the breaking strength and the rigor index. The breaking strength reached maximum over 12hrs after death and then gradually declined, and the rigor index was slowly increased and reached maximum over 18hrs after postmortem. Low temperature and acclimation to the sea water affected the degradation of adenosine triphosphate (ATP), accumulation of inosine monophosphate (IMP) or lactate. These results suggest that the palatability of tilapia muscle cultivated in the fresh water could be improved by acclimation to the sea water which induces the prerigor at the early state of postmortem and the physical changes of fish muscle.

• Animal Bioscience
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• v.34 no.7
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• pp.1193-1201
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• 2021

Objective: According to market demand, meat duck breeding mainly includes 2 breeding directions: lean Pekin duck (LPD) and fat Pekin duck (FPD). The aim of the present study was to compare carcass and meat quality traits between 2 strains, and to provide basic data for guidelines of processing and meat quality improvement. Methods: A total of 62 female Pekin ducks (32 LPDs and 30 FPDs) were slaughtered at the age of 42 days. The live body weight and carcass traits were measured and calculated. Physical properties of breast muscle were determined by texture analyzer and muscle fibers were measured by paraffin sections. The content of inosine monophosphate (IMP), intramuscular fat (IMF) and fatty acids composition were measured by high-performance liquid chromatography, Soxhlet extraction method and automated gas chromatography respectively. Results: The results showed that the bodyweight of LPDs was higher than that of FPDs. FPDs were significantly higher than LPDs in subcutaneous fat thickness, subcutaneous fat weight, subcutaneous fat percentage, abdominal fat percentage and abdominal fat shear force (p<0.01). LPDs were significantly higher than FPDs in breast muscle thickness, breast muscle weight, breast muscle rate and breast muscle shear force (p<0.01). The muscle fiber average area and fiber diameter of LPDs were significantly higher than those of FPDs (p<0.01). The muscle fiber density of LPDs was significantly lower than that of FPDs (p<0.01). The IMF of LPDs in the breast muscle was significantly higher than that in the FPDs (p<0.01). There was no significant difference between the 2 strains in IMP content (p>0.05). The polyunsaturated fatty acid content of LPDs was significantly higher than that of FPDs (p<0.01), and FPDs had higher saturated fatty acid and monounsaturated fatty acid levels (p<0.05). Conclusion: Long-term breeding work resulted in vast differences between the two strains Pekin ducks. This study provides a reference for differences between LPD and FPD that manifest as a result of long-term selection.

• Korean Journal of Poultry Science
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• v.45 no.2
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• pp.125-135
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• 2018

This study was conducted to evaluate the productivity and meat quality of three newly-developed crossbreds of Korean native chicken (2A, 2C, and 2D) as compared with commercial Korean native chicken (CKNC) and commercial broiler. Totally, 400 birds of different crossbreds were randomly allotted to eight pens, each with 50 birds. The birds were reared ad libitum and slaughtered at the age of 12 weeks. Fifty male chickens were slaughtered at the same day in the same slaughterhouse were selected for the comparison of meat quality. The crossbred 2C had greater body weight than that of CKNC (P<0.05), and had similar uniformity with lower death rate. Although shank length of 2C was the longest among the Korean native chicken breeds, the ratio of shank length to body weight was the lowest among them (P<0.05). The crossbred 2C had similar inosine 5'-monophosphate (IMP) content as that of CKNC in breast meat, and the highest IMP content in thigh meat (P<0.05). In a sensory analysis, the crossbred 2C generally showed, similar savory taste and texture as that of CKNC, and the overall acceptability of thigh meat was the highest in CKNC and broiler. Based on the present results, the possibility of commercialization of a newly-developed crossbred of Korean native chicken was confirmed.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.1
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• pp.93-103
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• 1996

The effects of salt and temperature on changes of K value, IMP, free amino acids and histamine concentration in Makerel muscle during storage were examined. The content of salt was 0, 3, 5 and 10% and storage temperature was at 0, 8, 16 and 2$0^{\circ}C$. 1. Content of IMP was 607.3mg% In raw material and as storage temperature was decreased and as salt content was increased, the rate of decrease in IMP was slow. 2. K value of raw material was 14% and rapidly increased as temperature increased and salt content decreased. 3. The time required to reach at 50% in K value was 13.6-16.6 days at $0^{\circ}C$ and 1.4-3.3 days at 2$0^{\circ}C$ in 0-10% salt content. 4. Except taurine and histidine, the contents of all free amino acids were slowly increased during storage at $0^{\circ}C$ and in high salt content but at 2$0^{\circ}C$ and in 0% salt they were more rapidly increased. The contents of Ala., Glu., Val.., Leu., Lys., and NH$_3$ were rapidly increased than the contents of Phe., Gly. and Ile. 5. Taurine and histidine were rapidly decreased at high temperature and in 0% salt during storage. 6. The storage condition which produced more than 100mg% in histamine was 3 days at 16$^{\circ}C$(180mg%) and 2$0^{\circ}C$(443.5mg%) in 0% salt and was 10days (163.1mg) at 16$^{\circ}C$ in 3% salt.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.700-707
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• 2013

The purpose of this study was to monitor physicochemical changes of olive flounder (Paralichthys olivaceus) muscle by iced water pre-treatment. Moisture content, crude fat content, nucleotide content, texture (hardness and toughness), and rigor mortis were assessed. The sensory evaluation was performed with a nine-point hedonic test. K-values, a parameter of fish flesh freshness, were also calculated from the content of nucleotides and their corresponding decomposition products. Pre-treatment of flounder flesh with iced water was found to be fresher compared to the control, as determined by a difference in the K-values. Iced water pre-treatment hastened postmortem stiffness, as judged from the rigor index, and increased inosine monophosphate (IMP), which is known to be a savory taste compound, more quickly as adenosine triphosphate (ATP) degradation proceeded.

• Korean Journal of Poultry Science
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• v.46 no.4
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• pp.255-262
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• 2019

The micronutrients and flavor compounds of three new native chicken strains (A, C, and D) being developed in a breeding program (Golden Seed Project) were compared with a commercial native chicken strain (H) and the Baeksemi (W, white semi broiler). After 100 male chicks in each strains were reared for 5 weeks, the breast muscles from randomly selected 40 birds were analyzed at 8 replications. Native chicken strain A had greater amounts of α-tocopherol and α-tocotrienol compared with strain W. Native chicken strains showed higher contents of vitamin B₁₂ than Stain W. Stain H strain had the highest values of cholesterol content and strain D did the lowest. There was no different content of most minerals between native chickens (A, C, D, and H) and W, but Cu were more contained in native chicken strains compared with W. In terms of nucleotide-related flavor compounds, Stain A had the lowest content of hypoxanthine and strain D had highest inosine monophosphate. Native chicken strains had higher contents of umami-related free amino acids (glutamate and aspartate) than W. Among native chickens, strain A had more amounts in the contents of taurine, tasty flavor compounds, and certain vitamins, despite of the relatively low growth productivity. This result will provide information to select a strain with characteristic meat quality in a chicken breeding program.

• Clinical and Experimental Pediatrics
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• v.50 no.7
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• pp.686-693
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• 2007

Purpose : Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), is a potent inhibitor of inosine-monophosphate dehydrogenase (IMPDH), a new immunosuppressive drug used. It was reported that MPA protected neurons after excitotoxic injury, induced apoptosis in microglial cells. However, the effects of MPA on hypoxic-ischemic (HI) brain injury has not been yet evaluated. Therefore, we examined whether MPA could be neuroprotective in perinatal HI brain injury using Rice-Vannucci model (in vivo) and in rat brain cortical cell culture induced by hypoxia (in vitro). Methods : Cortical cells were cultured using a 18-day-pregnant Sprague-Dawley (SD) rats and incubated in 1% $O_2$ incubator for hypoxia. MPA ($10{\mu}g/mL$) before or after a HI insult was treated. Seven-day-old SD rat pups were subjected to left carotid occlusion followed by 2 hours of hypoxic exposure (8% $O_2$). MPA (10 mg/kg) before or after a HI insult were administrated intraperitoneally. Apoptosis was measured using western blot and real-time PCR for Bcl-2, Bax, caspase-3. Results : H&E stain revealed increased brain volume in the MPA-treated group in vivo animal model of neonatal HI brain injury. Western blot and real-time PCR showed the expression of caspase-3 and Bax/Bcl-2 were decreased in the MPA-treated group In in vitro and in vivo model of perinatal HI brain injury, Conclusion : These results may suggest that the administration of MPA before HI insult could significantly protect against perinatal HI brain injury via anti-apoptotic mechanisms, which offers the possibility of MPA application for the treatment of neonatal HI encephalopathy.

• Korean Journal of Poultry Science
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• v.38 no.2
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• pp.137-144
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• 2011

The current work was carried out to investigate the effect of crossbred Korean native chickens (KNC) on fatty acid, amino acid and nucleotide-related compounds contents of chicken meat. A total of 360 male chicks (1d of age) was used in this work and were divided 4 groups as A) (KNC egg-meat type C strains ${\times}$ KNC meat type S strains) ${\times}$ Ross broiler, B) (KNC egg-meat type C strains ${\times}$ KNC meat type H strains) ${\times}$ KNC meat type S strains, C) (KNC native R strains ${\times}$ KNC meat type S strains) ${\times}$ KNC meat type H strains and D(White Semibroiler Chickens) strains for 5 weeks at the flat house. Palmitic acid and vaccenic acid were highest in C strain meat, and myristic acid and linolenic acid were lowest in A strain meat (p<0.05). Saturated fatty acid was lowest in C strain meats (p<0.05). Valine, leucine, phenylalanine and lysine of essential acid were low in A strain meat. Cystine, aspartic acid, glycine, alanine and proline were also low in A strain meat. Hypoxanthin (Hx) was high compared other strains at 5 weeks and low at 10 weeks. IMP was high compared other strains at 5 and 10 weeks. AMP has not significant difference among strains at 5 weeks but B strain was high other strains at 10 weeks. These results showed that C stain was excellent on the fact of nutrients compared to other strains. Consequently, the result of this work gave the basic data that needed to develope the new strains.

• Journal of Aquaculture
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• v.20 no.1
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• pp.19-25
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• 2007

For establishing a basal diet for the Pacific bluefin tuna Thunnus orientalis (PBT), feeding stimulants were initially identified by omission test using the synthetic extract of horse mackerel, Trachurus japonicus. Four feeding trials were conducted using juvenile PBT weighing $9.0{\pm}0.91\;g$ (trial 1, 2 and 3) and $1.6{\pm}0.23\;g$ (trial 4), which were originated from an artificial seedling production. The fish fed the casein diet with each test solution were added at the ratio of 100 g casein diet to 100 g jack mackerel muscle. A complete synthetic extract of jack mackerel containing all 3 fractions, amino acid, nucleotide and organic nitrogenous base, exhibited a comparable feeding stimulant activity compared to that of natural extract. The omission of nucleotide or amino acid fraction showed lower feeding activity, but the omission of other nitrogenous fraction maintained a similar feeding stimulant activity compared to that of the synthetic extract (trial 1). Inosine-5' monophosphate $Na_2$ (IMP) was identified as a major constituent for maintaining feeding activity. The mixture of L-alanine, L-glutamic acid, L-histidine, L-lysine, taurine and IMP induced a similar feeding activity compared to that of the synthetic extract (trial 2 and 3). In trial 4, the highest feeding activity was finally obtained in the mixture of L-histidine, L-glutamine and IMP, followed by the synthetic extract, the mixture of L-lysine, L-alanine and IMP, IMP and the mixture of L-histidine, L-glutamic acid, L-lysine and L-alanine. These results revealed that the mixture of L-histidine, L-glutamic acid and IMP for the proper feeding stimulant of PBT in this study.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.566-574
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• 2014

This study was conducted to compare the physicochemical composition and fermentation conditions of sliced, dried radish kimchi with flying fish roe (DFFR). The levels of crude protein, crude lipid, and crude ash in DFFR were higher than those in sliced, dried radish kimchi without flying fish roe (control). DFFR also contained higher levels of Fe and Ca, compared to the control. The inosine monophosphate (IMP) content of DFFR and control was 5.63 and 2.64 mg/100 g, respectively. The polyunsaturated fatty acid and DHA contents in DFFR were approximately 5 and 23 times higher than those in the control, respectively. The major free amino acids contained in these samples were arginine, proline, alanine, leucine, and valine. The number of cells belonging to the Leuconostoc species in DFFR was higher than that in the control. In sensory evaluation studies, DFFR scored the highest in terms of appearance, flavor, taste, and texture.