• Proceedings of the Korean Nutrition Society Conference
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• 1994.07a
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• pp.646-654
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• 1994

• Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.275-281
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• 2012

Yellow croaker Larimichthys polyactis muscle oil was extracted using an environmental friendly solvent, supercritical carbon dioxide (SC-$CO_2$), in a semi-batch flow extraction process. SC-$CO_2$ was applied at temperature $35^{\circ}C$ to $45^{\circ}C$ and $150^{\circ}C$ to $250^{\circ}C$ bar of pressure. The flow rate of $CO_2$ (27.79 g/min) was constant throughout the entire 1.5 h extraction period. The oil extraction yield was influenced by the physical properties of SC-$CO_2$ at different temperatures and pressures. The extracted oil was analyzed by gas chromatography to determine the fatty acid composition. According to our results, the SC-$CO_2$ extracted oil was high in eicosapentaenoic acid and docosahexaenoic acid. In addition, the SC-$CO_2$ extracted oil showed greater stability than n-hexane extracted oil based on the peroxide value and acid value. Thus, the quality of yellow croaker oil obtained by SC-$CO_2$ extraction was slightly higher than that of oil obtained by n-hexane extraction.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.779-792
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• 1995

The effects of deoxygenizer (Deoxy) and sodium-erythorbate (Na-ery) on the changes in fatty acid compositions were investigated to prevent the loss of n-3 polyunsaturated fatty acids in lipid of bolied and dried-anchovy during storage. After storage for 5 months, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) of total lipid (TL) in Deoxy group decreased only $3.0\%\;and\;0.5\%$, respectively, compared to those of before storage. However, those in Control group decreased 9.5\%\;and\;2.3\%,$ respectively. In the case of Na­ery group, the percentages of DHA and EPA decreased were lower than those of Control. Most of DHA and EPA in n was lost in the early stage of storage. Total DHA remained in phospholipid (PL), triglyceride (TG), and free fatty acid (FFA) fractions after storage for 5 months were $98\%,\;66\%\;and\;62\%$ in Deoxy, Na-ery and Control group, respectively, and total EPA remained was slightly high level compared with those of DHA. The loss of DHA was more in PL than in TG. Consequently, deoxygenizer was recognized as a good material to prevent the loss of DHA and EPA of the boiled and dried-anchovy during storage.

• BMB Reports
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• v.33 no.6
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• pp.499-505
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• 2000

The level of long-chain n-3 fatty acids in chicken and pork can be increased by changing the diet of the animals. Increased levels of these essential fatty acids improve cardiovascular health in humans. The purpose of this study was to study the effects of the consumption of pork and chicken enriched in docosahexaenoic acid (DHA) on plasma lipids. The consumption of these products decreased the levels of two cardiovascular risk factors, LDL-cholesterol and triacylglycerols, in the plasma of female college students. The effect on LDL-cholesterol differed from that of fish oil, which does not affect the level of LDL-cholesterol. The proportions of DHA in the triacylglycerols and the glycerophospholipids were increased markedly. The greatest changes in the glycerophospholipids were in the ether types of the ethanolamine glycerophospholipids. Dietary DHA appears to be incorporated preferentially into the plasma ethanolamine plasmalogens, which can act as antioxidants. This agrees with our hypothesis that DHA stimulated the transcription of the genes for peroxisomal enzymes that are required for plasmalogen synthesis.

• Journal of Nutrition and Health
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• v.34 no.6
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• pp.626-636
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• 2001

To compare the effect of three kinds of n-3 fatty acids-eicosapentaenoic acid(EPA), docosahexaenoic acid(DHA) and perilla oil (PO)-on serum and liver lipid levels and fatty acid composition of liver phospholipid(PL) at low fat level(5%, w/w), 4-weeks old Sprague-Dawley rats were fed with one of five different oil diets for 4 weeks. Beef tallow(BT) and corn oil(CO) was used as control for sturated or n-6 fatty acid respectively. Se겨m concentrations of cholesterol(TC) and phospholipid(PL) were lower in PO DHA and EPA groups than in BT and CO groups. HDL-cholesterol levels were higher in CO and PO groups than in EPA, DHA and BT groups. Liver PL concentrations were higher in DHA and EPA groups than in CO, PO and BT groups, but liver TC and heal PL and TC concentrations did not show any significant difference among groups. Hepatic fatty acid composition of phosphatidylcholine (PC) and phosphatidylethanolamine (PE), two major phospholipids in liver, reflected their dietary fatty acid composition. In PC and PE, total percentage own-6 series was higher in CO group than in any other groups, and that own-3 series was higher in DHA and PO groups than in EPA, CO and BT groups. Moreover, the ratio of 20 : 4/18 : 2 was lower in PO and DHA groups than in EPA, CO and BT groups. On the contrary, the percentage of C22 : 6 was lower in EPA, CO and BT groups than in PO and DHA groups. These results revealed that n-3 series(EPA, DHA and PO) were more effective in lowering um lipids than n-6 fatty acids or saturated fatty acid. Based on the results of fatty acid composition of hepatic phospholipid, we suggest that the dietary effect of PO and DHA on antiatherogenic characteristics seems to be similar extent. In addition, the effect of EPA might not be significantly different from that of BT or CO in the view of eicosanoids production from the precursor fatty acid. These difference of hepatic fatty acid composition might come from other characteristics of dietary oil as well as the type of unsaturation, not from the carbon chain length or the degree of unsaturation of n-3 fatty acid.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.768-774
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• 2007

To study the effect of dietary docosahexaenoic acid (DHA) enrichment on the expression of hepatic genes in pigs, weaned, crossbred pigs (30 d old) were fed diets supplemented with either 2% tallow or DHA oil for 18 d. Hepatic mRNA was extracted. Suppression subtractive hybridization was used to explore the hepatic genes that were specifically regulated by dietary DHA enrichment. After subtraction, we observed 288 cDNA fragments differentially expressed in livers from pigs fed either 2% DHA oil or 2% tallow for 18 d. After differential screening, 7 genes were found to be differentially expressed. Serum amyloid A protein 2 (SAA2) was further investigated because of its role in lipid metabolism. Northern analysis indicated that hepatic SAA2 was upregulated by dietary DHA enrichment (p<0.05). In a second experiment, feeding 10% DHA oil for 2d significantly increased the expression of SAA2 (compared to the 10% tallow group; p<0.05). The porcine SAA2 full length cDNA sequence was cloned and the sequence was compared to the human and mouse sequences. The homology of the SAA2 amino acid sequence between pig and human was 73% and between pig and mouse was 62%. There was a considerable difference in SAA2 sequences among these species. Of particular note was a deletion of 8 amino acids, in the pig compared to the human. This fragment is a specific characteristic for the SAA subtype that involved in acute inflammation reaction. Similar to human and mouse, porcine SAA2 was highly expressed in the liver of pigs. It was not detectable in the skeletal muscle, heart muscle, spleen, kidney, lung, and adipose tissue. These data suggest that SAA2 may be involved in mediation of the function of dietary DHA in the liver of the pig, however, the mechanism is not yet clear.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.5
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• pp.345-356
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• 2019

Docosahexaenoic acid (DHA), an omega-3-fatty acid, modulates multiple cellular functions. In this study, we addressed the effects of DHA on human umbilical vein endothelial cell calcium transient and endothelial nitric oxide synthase (eNOS) phosphorylation under control and adenosine triphosphate (ATP, $100{\mu}M$) stimulated conditions. Cells were treated for 48 h with DHA concentrations from 3 to $50{\mu}M$. Calcium transient was measured using the fluorescent dye Fura-2-AM and eNOS phosphorylation was addressed by western blot. DHA dose-dependently reduced the ATP stimulated $Ca^{2+}$-transient. This effect was preserved in the presence of BAPTA (10 and $20{\mu}M$) which chelated the intracellular calcium, but eliminated after withdrawal of extracellular calcium, application of 2-aminoethoxy-diphenylborane ($75{\mu}M$) to inhibit store-operated calcium channel or thapsigargin ($2{\mu}M$) to delete calcium store. In addition, DHA ($12{\mu}M$) increased ser1177/thr495 phosphorylation of eNOS under baseline conditions but had no significant effect on this ratio under conditions of ATP stimulation. In conclusion, DHA dose-dependently inhibited the ATP-induced calcium transient, probably via store-operated calcium channels. Furthermore, DHA changed eNOS phosphorylation suggesting activation of the enzyme. Hence, DHA may shift the regulation of eNOS away from a $Ca^{2+}$ activated mode to a preferentially controlled phosphorylation mode.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.211-215
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• 1989

The fatty acid composition of lipids separated from 14 kinds of canned fish and shellfish products from the market were examined. The crude lipid contents of canned fish and shellfish products showed wide difference (1.3-15.2%) depending on raw materials and kinds of products. Fatty acid composition of products were mainly consisted of polyenoic acid(34.5-61.4%), and followed by saturated acid(24.5-47.8%), monoenoic acid(12.4-32.0%). The major fatty acids were palmitic acid, palmitoleic acid oleic acid, eicosapentaenoic acid and docosahexaenoic acid. In case of canned tuna in oil and canned smoked oyster in oil, linoleic acid was the most predominant component(48.2%, 34.6%). Judging from the results, canned fish and shellfish products were abundant of the polyunsaturated fatty acids in spite of the high temperature sterilization and lone storage periods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.660-666
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• 1997

Changes of chemical and nutritional composition were investigated in low salt-dried Yellow corvenia muscle during frozen storage at $-20^{\circ}C$. Moisture contort of Yellow corvenia was not significantly changed until after 5 months frozen storage. Salinity was $0.28\%$ in fresh Yellow corvenia and $2.30\%$ in the salted sample. Acidity of the fish muscle was increased in excess of 5 months storage. TBA value was increased by a little amount untel 1 month of storage and significantly incraeased in 3 months of storage. Free fatty acid was increased during frozen storage with rapid increase up to 1 month storage. VBN was increased after 1month storage and amino type nitrogen was increased in 5 months of storage. Major free amino acids were glutamic acid, alanine, glycine and lysine, and composition ratio of most free amino acids were not changed untel after 5 months storage. Polyenoic acid contents were decreased after storage and major fatty acids were palmitic acid (16 : 0), stearic arid (18 : 0) and major fatty acids were palmitic acid (16 : 0), stearic acid (18 : 0) and docosahexaenoic acid (22 : 6). From the results of chemical experiments, low salt-dried yellow corvenia would not be stored at $20^{\circ}C$ for more than 5 months.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.565-569
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• 2003

The objective of this experiment was to determine the effects of different levels of refined cod liver oil (RCLO) on laying performance, n-3 polyunsaturated fatty acids composition (n-3 PUFAs) and the organoleptic evaluation of duck egg yolks. A total of 180 30 wk old laying Tsaiya ducks, at the beginning of peak production, were allotted into 6 treatments with 3 replicates each. Ducks were fed one of the 6 experimental diets, supplemented with 2% tallow (control) and graded levels of RCLO at 2, 3, 4, 5, and 6% to a corn-soybean diets, respectively, for 6 wks. All of the experimental diets were formulated to be both isocaloric and isonitrogenous. Feed and water were supplied ad libitum throughout the experimental period. The results indicated that the RCLO supplementation levels did not affect (p>0.05) egg production, egg mass, feed intake, feed efficiency or body weight change. Egg weight was the lightest when the ducks received the 6% RCLO diet. The eicosapentaenoic acid, docosahexaenoic acid, and total n-3 PUFAs contents in the yolks increased with increasing RCLO supplementation. The taste and general acceptability of the hard-boiled eggs were not significantly different among the treatments. However, a fishy flavor was much higher when ducks were fed diets supplemented with 5% and 6% RCLO diets.