• Fisheries and Aquatic Sciences
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• 제25권1호
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• pp.31-39
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• 2022

To clarify the factors influencing the physical properties of fish after heat treatments, we investigated changes in the properties of proteins in the dorsal ordinary and dark muscle of yellowtail (Seriola quinqueradiata) heated under different conditions commonly used for the purposes of food hygiene. High-temperature/short-time heating (85℃ for 90 s and 75℃ for 60 s) affected the protein solubility more than low-temperature/long-time heating (63℃ for 30 min). Sodium dodecyl sulphate-polyacrylamide gel electrophoresis and differential scanning calorimetry showed that low-temperature/long-time heating reduced the degree of actin denaturation in fish compared with that by other heating conditions. In addition, collagen solubility was enhanced with low-temperature/long-time heating. Therefore, these results suggest that differences in the degree of actin and collagen denaturation are responsible for the enhanced meat tenderness and diminished meat shrinkage, resulting from low-temperature/long-time heating.

• Asian-Australasian Journal of Animal Sciences
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• 제10권1호
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• pp.1-7
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• 1997

This experiment was conducted with total 960 brown layers, consisted of 8 treatment to investigate the effects of dietary chromium as chromium picolinate on egg production, egg quality, nutrient utilizability, serum traits and mortality in brown layers. Layers were fed diets with two levels of dietary protein (14% and 16%) and supplemented with 0, 200, 400, 800 ppb/kg of chromium as chromium picolinate, respectively. The highest egg production, egg weight and egg mass were found in 800 ppb chromium picolinate supplementation group with high protein level (16%) (p < 0.05). Although there was no significant difference, layers receiving 400 ppb of chromium picolinate with high protein (16%) represented the lowest broken eggs. The utilization of energy, dry matter and crude protein of 400 ppb chromium picolinate group with low protein level (14%) were significantly higher than those of control or other chromium picolinate group (p < 0.05). 400 ppb chromium picolinate with low protein level (14%) showed the lowest serum glucose concentration. But serum glucose concentrations in all treatments showed no significant differences. Present date revealed that the lowest serum cholesterol concentration of layers was found at 400 ppb chromium picolinate group with high protein level (16%) (p < 0.05). Crude protein content in yolk was significantly higher in eggs of layers received 800 ppb chromium picolinate and the lowest in eggs from layers received 400 ppb chromium picolinate among chromium picolinate levels (p < 0.05). Mortality was remarkably decreased by chromium picolinate supplementation and the lowest mortality value was found in layres receiving 800 ppb chromium picolinate with high protein level.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.236-244
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• 2006

This study was designed to determine the effects of daidzein (DE) on hepatic lipid metabolism in chicks fed with low protein (LP) diet based on casein. In experiment 1, the male chicks were fed with one of the three levels of dietary protein containing 10.95%, 21.9% and 43.8% protein content for 2 days. In experiment 2, the chicks were fed one of the three levels of protein with or without DE at 1,000 mg/kg diet for 2 days. Experiment 3 was conducted to compare DE (LP+DE) with estradiol (LP+E2) in chicks fed with LP diet for 7 days. Plasma lipid profiles, hepatic lipid profiles, activities of hepatic malic enzyme and isocitrate dehydrogenase (ICDH) were measured. Transcriptions of hepatic fatty acid synthase, apolipoprotein-B (APO-B), and fructose bisphosphatase mRNA were measured by RT-PCR. Increasing dietary protein levels markedly decreased the concentrations of plasma triglycerides, hepatic total lipids, hepatic TG, and the mRNA transcriptions while the increased dietary protein levels increased hepatic ICDH activities in experiment 1. In experiment 2, the effects of dietary protein levels on blood and hepatic lipid content were more prominent than those of the additional DE. Interestingly, plasma TG levels were affected by DE supplementation (p<0.05). In experiment 3, DE inhibited APO-B mRNA expressions and stimulated the accumulation of lipid in the liver through mechanisms different from E2. In this study, we demonstrate that DE has beneficial effects on blood lipid profiles, but that it inhibits APO-B mRNA transcription and aggravates the fatty liver induced by LP diet in chicks.

• 한국작물학회지
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• 제51권1호
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• pp.14-25
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• 2006

Response of grain yield and milled-rice protein content to nitrogen (N) rates at various growth stages is critical for quantifying real-time and real-amount of applied N requirement for target grain yield and protein content. An experiment including 10 N rate treatments at transplanting, tillering and panicle initiation stages with four rice cultivars in 2003, 6 N treatments with two rice cultivars in 2004 and 2005 was conducted. Increase of N rates at PIS significantly increased both grain yield and milled-rice protein content but increase of N rates at tillering stage significantly increased grain yield but not milledrice protein content. Therefore, high grain yield and low milled-rice protein content would be difficult to obtain only by adjusting N rates at PIS. Internal N use efficiency (INUE) was 60.5 kg grain/kg N accumulation on an average over N treatments, cultivars, and experimental years, showing considerable reduction especially at high shoot N accumulation in the experimental year of low sunshine duration. Milled-rice protein content tended to increase almost linearly with increasing shoot N accumulation, but it revealed big variation even at the same shoot N accumulation at harvest. Milled-rice protein content decreased with increasing INUE. N accumulation in the milled rice increased at an almost constant proportion of 45.5 percent of the shoot N accumulated at harvest, showing slight decresing proportion with the increasing shoot N accumulation.

• Asian-Australasian Journal of Animal Sciences
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• 제9권1호
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• pp.31-35
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• 1996

An experiment was conducted on rainbow trout(Oncorhynclus mykiss) for eight weeks to investigate the growth performance of the fish fed with different dietary protein with constant diet energy of $20kJg^{-1}$. Four diets containing 25, 30, 35 and 40% crude protein were used. The highest mean final weight was obtained for the fish fed with diet having 35% protein. Growth performance in terms of Specific Growth Rate (SGR), Food Conversion Ratio (FCR) and Protein Efficiency Ratio (PER) were calculated for each diet. There were no significant differences in SGR but the highest value was exhibited by fish fed with 35% protein diet. Significant differences were found among FCR of different diets. Diets with 35 and 40% crude protein gave better FCR value than that of 25 and 30% crude protein. Although significant differences were not found between PER of different diets but PER of diet with 35% protein was found to be better than PER of both high and low protein diets (diets of 40 and 30% crude protein). It is concluded that diet having 35% protein with protein energy ratio of $17.53mgkJ^{-1}$ was suitable for rainbow trout (O. mykiss) among the protein spectrum used.

• Journal of Radiation Protection and Research
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• 제40권3호
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• pp.187-193
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• 2015

Deleterious effects of high dose radiation exposure with high-dose-rate are unarguable, but they are still controversial in low-dose-rate. The regulator of G-protein signaling (RGS) is a negative regulator of G protein-coupled receptor (GPCR) signaling. In addition, it is reported that irradiation stress led to GPCR-mediated mitogen-activated protein kinase (MAPK) and phosphotidylinositol 3-kinase (PI3-k) signaling. The RGS mRNA expression profiles by whole body radiation with low-dose-rate has not yet been explored. In the present study, we, therefore, examined which RGS was modulated by the whole body radiation with low-dose-rate ($3.49mGy{\cdot}h^{-1}$). Among 16 RGS expression tested, RGS6, RGS13 and RGS16 mRNA were down-regulated by low-dose-rate irradiation. This is the first report that whole body radiation with low-dose-rate can modulate the different RGS expression levels. These results are expected to reveal the potential target and/or the biomarker proteins associated with male testis toxicity induced by low-dose-rate irradiation, which might contribute to understanding the mechanism beyond the testis toxicity.

• Journal of Dairy Science and Biotechnology
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• 제40권3호
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• pp.134-142
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• 2022

Protein-enriched dairy powder is widely consumed to promote muscle synthesis. Recently, in Korea, elderly people have also begun consuming protein powder products to prevent muscle loss. However, these protein-enriched powders have poor flowability and hydration properties because of the fine particles of spray-dried milk protein powder. Therefore, in this study, the fluidized bed agglomeration process was used to solve these problems. The rheological and physical properties of milk protein isolate (MPI)/skim milk powder (SMP) mixtures were effectively improved via fluidized bed agglomeration. The particle size of the MPI/SMP mixtures significantly increased from 35.7-58 ㎛ to 118-136 ㎛, the flowability level improved from fair (21.4-26.3) to good (15.7-16.3), and the cohesiveness level changed from intermediate (1.27-1.36) to low (1.18-1.19) after fluidized bed agglomeration. In addition, the wetting time of the agglomerated MPI/SMP mixtures was effectively reduced to 4.67-58.3 s by fluidized bed agglomeration. These findings may be useful for manufacturing protein-enriched dairy powders with good instant properties.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2005년도 춘계 학술발표대회
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• pp.105-105
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• 2005

• Asian-Australasian Journal of Animal Sciences
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• 제25권10호
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• pp.1457-1465
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• 2012

Intestinal phosphate (Pi) absorption across the apical membrane of small intestinal epithelial cells is mainly mediated by the type IIb Na-coupled phosphate co-transporter (NaPi-IIb), but its expression and regulation in the chicken remain unclear. In the present study, we investigated the mRNA and protein levels of NaPi-IIb in three regions of chicken small intestine, and related their expression levels to the rate of net phosphate absorption. Our results showed that maximal phosphate absorption occurs in the jejunum, however the highest expression levels of NaPi-IIb mRNA and protein occurs in the duodenum. In response to a low-Pi diet (TP 0.2%), there is an adaptive response restricted to the duodenum, with increased brush border membrane (BBM) Na-Pi transport activity and NaPi-IIb protein and mRNA abundance. However, when switched from a low-(TP 0.2%) to a normal diet (TP 0.6%) for 4 h, there is an increase in BBM NaPi-IIb protein abundance in the jejunum, but no changes in BBM NaPi-IIb mRNA. Therefore, our study indicates that Na-Pi transport activity and NaPi-IIb protein expression are differentially regulated in the duodenum vs the jejunum in the chicken.

• 수산경영론집
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• 제15권1호
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• pp.114-130
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• 1984

The structure of food demand is being changed according to the improvement of living standard. Moreover, the intake of animal protein is stepping up. This paper considers how much fresh-fish is consumed as source of animal protein and what extent fresh-fish have substitutive relation for meat with special reference to the change of income and price of fresh-fish and meat. And it is thought to be important work to estimate demand of fresh-fish in attemps to the prediction of food consume pattern and fishing industries in the future. For this estimation, the substitutive relation of fresh-fish and meat is essentially studied. The main conclusions of this study can be drawn as follows: 1. Fresh-fish and meat have substitutive relation on price axis. By the way, increase in demand of A (fresh-fish which have comparatively low price) can be expected according to the low of it's price against meat, but B (fresh-fish wihich have comparatively middle-high price) have peculiar demand without substitutive relation for meat. 2. Demand of A and B rise according to the income increases. 3. It is not sufficient to explain substutive relation of fresh-fish and meat without income variable. 4. Income increases bring about the more increase in demand of B than A. By the way, price increases bring about the decrease of it's consume expenditure, but A have fundamental demand as the source of animal protein. 5. In future, the intake of animal protein will step up. By the way, meat will occupy the more portion of the source of animal protein than fresh-fish.