• Asian-Australasian Journal of Animal Sciences
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• 제19권7호
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• pp.1047-1053
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• 2006

The current study was designed to determine the effects of dietary docosahexaenoic acid (DHA) on fatty acid deposition in egg yolk and various tissues of laying Tsaiya ducks, and on the mRNA concentrations of hepatic lipogenesis-related transcription factors. Thirty laying ducks were randomly assigned to three treatments with diets based on corn-soybean meal (ME: 2803 kcal/kg; CP: 17.1%; Ca: 3.4%) supplemented with 0% (control diet), 0.5% or 2% algal DHA oil. The DHA content in egg yolks of the ducks was elevated significantly (p<0.01) with the supplementation of dietary DHA. The DHA percentage of the total fatty acids in the egg yolk of laying ducks was 0.5%, 1.3% and 3.4% for 0%, 0.5% and 2% algal DHA oil treatments, respectively, for the $1^{st}$ week, and 0.5%, 1.5% and 3.3% for the $2^{nd}$ week. Therefore, algal DHA oil can be utilized by laying Tsaiya ducks to enhance the egg-yolk DHA content. The concentrations of triacylglycerol (TG) and cholesterol in plasma of laying Tsaiya ducks were not affected by dietary DHA treatments (p>0.05). The DHA concentration in plasma, liver, and skeletal muscle was increased with the addition of dietary algal DHA oil (p<0.05). The mRNA abundance of sterol regulatory element binding protein 1 (SREBP1) and SREBP2 in the livers of laying Tsaiya ducks was not affected by dietary DHA, suggesting that the expression of these transcription factors is tightly controlled and not sensitive to DHA treatments.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1451-1456
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• 2005

To study the acute effect of dietary docosahexaenoic acid (DHA, $C_{22:6}$) on the expression of adipocyte determination and differentiation-dependent factor 1 (ADD1) mRNA in pig tissues, weaned, crossbred pigs (28 d of age) were fed with either 10% (on as-fed basis) tallow (high stearic acid), soybean oil (high linoleic acid), or high DHA algal oil for 2 d. The plasma and liver DHA reflected the composition of the diet. The adipose tissue and skeletal muscle DHA did not reflect the diet in the short term feeding. The results also showed that the diet containing 10% algal DHA oil significantly decreased the total plasma cholesterol (39%) and triacylglycerol (TG; 46%) in the pigs. Soybean oil significantly decreased plasma TG (13.7%; p<0.05), but did not have an effect on plasma cholesterol. The data indicate that different dietary fatty acid compositions have different effects on plasma lipids. The ADD1 mRNA was decreased (p<0.05) in the liver of DHA oil-treated pigs compared with the tallow-treated pigs. The diets did not have significant effect on the ADD1 mRNA in adipose tissue. Addition of algal DHA oil in the diet increased acyl CoA oxidase (ACO) mRNA concentration in the liver, suggesting that dietary DHA treatment increases peroxisomal fatty acid oxidation in the liver. However, dietary soybean oil supplementation did not affect mRNA concentrations of ADD1 or ACO in the tissues of pigs. Because ADD1 increases the expression of genes associated with lipogenesis, and ACO is able to promote fatty acid oxidation, feeding DHA oil may change the utilization of fatty acids through changing the expression of ADD1 and ACO. Therefore, feeding pigs with high DHA may lead to lower body fat deposition.

• 한국축산식품학회지
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• 제43권2호
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• pp.220-231
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• 2023

Although omega-3 fatty acids including docosahexaenoic acid (DHA) contain various health-promoting effects, their poor aqueous solubility and stability make them difficult to be induced in dairy foods. The aims of this research were to manufacture casein derivative-based delivery system using acid-induced gelation method with glucono-σ-lactone and to investigate the effects of production variables, such as pH and charged amount of linoleic acid, on the physicochemical properties of delivery systems and oxidative stability of DHA during storage in model milk. Covalent modification with linoleic acid resulted in the production of casein derivatives with varying degrees of modification. As pH was reduced from 5.0 to 4.8 and the charged amount of linoleic acid was increased from 0% to 30%, an increase in particle size of casein derivative-based delivery systems was observed. The encapsulation efficiency of DHA was increased with decreased pH and increased charged amount of linoleic acid. The use of delivery system for DHA resulted in a decrease in the development of primary and secondary oxidation products. An increase in the degree of modification of casein derivatives with linoleic acid resulted in a decrease in the formation of primary and secondary oxidation products than of free DHA indicating that delivery systems could enhance the oxidative stability of DHA during storage in model milk. In conclusions, casein derivatives can be an effective delivery system for DHA and charged amount of linoleic acid played a key role determining the physicochemical characteristics of delivery system and oxidative stability of DHA.

• 생명과학회지
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• 제19권10호
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• pp.1417-1423
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• 2009

선행된 연구에서 나타난 n-3 지방산 결핍 식이에 DHA 첨가는 뇌 기능 개선효과가 나타났으나 n-3 지방산이 적절히 함유된 식이에 DHA 첨가는 유의적 뇌 기능 향상효과가 나타나지 않았다. 이러한 결과에 대한 설명으로 본 연구에서는 필수 지방산 함량이 다른 식이, 즉 n-3 지방산 결핍 및 적절군에 각각 DHA를 첨가하여 뇌 및 간의 지방산 조성에 미치는 영향에 대하여 검토하였다. N-3 지방산이 결핍된 식이군(Def)의 체중 및 뇌의 무게는 DHA를 첨가한 식이군(Def+DHA)이나 n-3 지방산이 적절히 함유된 식이군(Adq) 및 DHA 첨가군(Adq+DHA)에 비해 유의적으로 높았다(p<0.05). 뇌의 지방산 조성 결과에서 n-6계 지방산들 중 특히 22:5n-6의 함량이 n-3 지방산 결핍군(Def)에서 현저히 높았으며 20:4n-6 및 22:4n-6의 함량도 이 식이군(Def)에서 높았으나 18:2n-6 및 20:3n-6의 함량은 낮았다(p<0.05). 총 n-3계 지방산 및 22:6n-3의 함량은 예상했듯이 n-3 지방산 결핍군(Def)에서 가장 낮았으며 다른 식이군들과 비교했을 때 약 64% 감소됨을 살펴볼 수가 있었다. 또한 n-6/n-3의 비도 n-3 지방산 결핍군(Def)에서 3.35로 식이군들 중 유의적으로 높았다(p<0.05). 흥미로운 것은 n-3 지방산 결핍에 DHA를 첨가한 식이군(Def+DHA)의 경우, 뇌의 22:6n-3 함량이 13.1%로 n-3 지방산 적절군(Adq) 및 DHA 첨가군(Adq+DHA)과 유의적 차이가 없었다. 간의 지방산 조성 결과에서 뇌의 지방산 조성과 유사하게 n-6 지방산들 중 특히 22:5n-6의 함량이 n-3 지방산 결핍군(Def)에서 현저히 높았으며(p<0.05), n-3 적절군(Adq)의 경우, DHA 첨가군(Adq+DHA)과 비교했을 때 대부분의 n-6계 지방산의 함량이 유의적으로 높았다(p<0.05). N-3 결핍군에 DHA의 첨가군(Def+DHA)은 총 n-3계 지방산 및 22:6n-3의 함량이 n-3 결핍군(Def)에 비해 현저히 높았다(p<0.05). 특히 이 식이군(Def)의 22:6n-6의 함량은 n-3 적절군(Adq) 및 DHA 첨가군(Adq+DHA)보다 더 높은 수치를 나타내었다. 또한 n-3 지방산이 결핍된 동물(Def)의 간에서 18:3n-3의 함량을 거의 찾을 수가 없었으나 DHA 첨가군(Def+DHA)의 경우 가장 높은 함량을 나타내었다. 이는 n-3 지방산 결핍군(Def)의 경우 거의 모든 18:3n-3가 생체 내에서 고도로 불포화된 지방산으로 전환되기 위해 사용된 것으로 사료된다. 따라서 본 연구의 결과로부터 n-3 지방산이 결핍된 군의 경우 DHA 첨가로 인하여 뇌 DHA 함량 증가와 더불어 뇌 기능이 개선되었음을 살펴 볼수가 있었다. 반면 이미 뇌의 DHA가 포화상태인 n-3 지방산이 적절히 함유된 식이의 경우 DHA의 부가적인 첨가는 뇌기능 향상면에서는 유의적 효과가 나타내지 않았음을 뇌의 지방산 조성으로 확인 할 수가 있었다.

• Journal of Nutrition and Health
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• 제39권4호
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• pp.357-365
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• 2006

DHA, one of w-3 fatty acids, modulates cell growth or death though the changes of apoptotic signaling in human endothelial ECV304 cells. We investigated the effects of DHA on the changes of apoptotic signaling in human vascular endothelial ECV304 cells using lipid peroxidation (LPO) metabolites. LPO could be originated by dietary polyunsaturated fatty acids such as linoleic acid(LA), arachidonic acid(AA) and docosahexaenoic acid (DHA). DHA caused cell death of ECV304 cells compared to LA, AA or control as evidenced by changes in cell morphology and MTT assay. LPO levels was significantly elevated by 10 fold in DHA-treated ECV 304 cells and caspase-3 activity was increased by DHA corresponding to increasing incubation times compared to control. One of reasons of the cell death in DHA-treated ECV304 cells could be expected that caspase activity, marker for mitochondrial damages, might be triggered by the increasing LPO levels. Our results strongly indicated that DHA induced LPO production has an important role on apoptotic signaling pathway in ECV304 cells. LPO production in endothelial cells which was metabolized by oxidation of dietary PUFA, might be one of risk factors in the initial progression of atherosclerosis.

• 한국수산과학회지
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• 제47권1호
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• pp.31-38
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• 2014

Docosahexaenoic acid (DHA, 22:6n-3) and ecosapentaenoic acid (20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. It is thought that DHA has important functions in brain and retinal tissues. Thraustochytrids, a group of marine protists, are capable of heterotrophic growth, and are potential omega-3 producers for industrial use, especially the members of the Schizochytrium and Thraustochytrium genera. The aims of this work were to isolate, identify and screen thraustochytrids from 17 different locations. Twenty-three isolates were screened for biomass, total fatty acid (TFA) and DHA content. Analysis of the fatty acid methyl esters revealed four distinct clusters biomass ranged from $8.68-9.36gL^{-1}$, and lipid and DHA contents ranged from $3.11-4.10gL^{-1}$ and $1.05-1.93gL^{-1}$ biomass, respectively. B-12 isolates were screened for biomass ($9.36gL^{-1}$), TFA ($4.10gL^{-1}$) and DHA (47.01%, w/w) content. C-6 isolates were also screened for biomass ($8.92gL^{-1}$), TFA ($3.30gL^{-1}$) and DHA (49.41%, w/w) content. The 18S rRNA gene sequencing results identified Schizochytrium mangrovei as B-12 and Crypthecodium cohnii as C-6.

• Nutrition Research and Practice
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• 제13권4호
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• pp.286-294
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• 2019

BACKGROUND/OBJECTIVES: Docosahexaenoic acid (DHA), an n-3 long chain polyunsaturated fatty acid (LCPUFA), is acquired by dietary intake or the in vivo conversion of ${\alpha}$-linolenic acid. Many enzymes participating in LCPUFA synthesis are regulated by peroxisome proliferator-activated receptor alpha ($PPAR{\alpha}$). Therefore, it was hypothesized that the tissue accretion of endogenously synthesized DHA could be modified by $PPAR{\alpha}$. MATERIALS/METHODS: The tissue DHA concentrations and mRNA levels of genes participating in DHA biosynthesis were compared among $PPAR{\alpha}$ homozygous (KO), heterozygous (HZ), and wild type (WT) mice (Exp I), and between WT mice treated with clofibrate ($PPAR{\alpha}$ agonist) or those not treated (Exp II). In ExpII, the expression levels of the proteins associated with DHA function in the brain cortex and retina were also measured. An n3-PUFA depleted/replenished regimen was applied to mitigate the confounding effects of maternal DHA. RESULTS: $PPAR{\alpha}$ ablation reduced the hepatic Acox, Fads1, and Fads2 mRNA levels, as well as the DHA concentration in the liver, but not in the brain cortex. In contrast, $PPAR{\alpha}$ activation increased hepatic Acox, Fads1, Fads2, and Elovl5 mRNA levels, but reduced the DHA concentrations in the liver, retina, and phospholipid of brain cortex, and decreased mRNA and protein levels of the brain-derived neurotrophic factor in brain cortex. CONCLUSIONS: LCPUFA enzyme expression was altered by $PPAR{\alpha}$. Either $PPAR{\alpha}$ deficiency or activation-decreased tissue DHA concentration is a stimulus for further studies to determine the functional significance.

• 한국수산과학회지
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• 제47권2호
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• pp.144-153
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• 2014

Both docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. Lipids in microbial cells play various biological roles and, consequently, much research has been carried out on their role in cell physiology. The lipid composition of microorganisms can exhibit considerable variations depending on environment. The effects of culture conditions, temperature (15, 20, 24, 28, 32 and $36^{\circ}C$), salinity (10, 20, 30, 40 and 50 psu), pH (pH5, 6, 7, 8 and 9), rotation speeds (50, 100, 150 and 200 rpm), carbon sources, nitrogen sources and C/N ratio on the production of docosahexaenoic acid, fatty-acid profiles, and acids secreted to the broth culture by the oleaginous microorganism, Schizochytrium mangrovei (KCTC 11117BP), were studied. Temperature (initially $28^{\circ}C$), salinity (20 psu), pH (pH7), rotation speeds (100 rpm), organism fatty acids, and secreted acids in the broth were varied during cultivation of S. mangrovei. At pH 7.0, S. mangrovei was able to accumulate lipids up to 40% of its biomass, with 13% (w/w) DHA content. The monosaccharides glucose and fructose, and yeast extract were suitable carbon and nitrogen sources, respectively. The primary omega-3 polyunsaturated fatty acid produced was docosahexaenoic acid.

• Journal of Nutrition and Health
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• 제56권6호
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• pp.655-666
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• 2023

Purpose: Gestational nutrition has an impact on the growth and development of the fetus. Choline (C) and docosahexaenoic acid (DHA) are important and essential nutrients for humans that play a role in the structural integrity of the membranes as well as signalling. C is used in the synthesis of phosphatidylcholine, and cell membranes are highly enriched with DHA. The dietary intake of C or DHA during pregnancy directly influences fetal development. Currently, there is no evidence to prove the effectiveness of the combined dietary supplementation of both C and DHA during gestation on developmental outcomes in the offspring. Methods: The current study was designed to assess the physical, sensory, and motor development of rat pups born to mothers supplemented with C and/or DHA during the entire gestational period. Pregnant rat dams were divided into the following five groups: Normal control (NC), Saline control (SC), Choline (C), DHA, and Choline+DHA (C+DHA). The NC dams did not receive any supplementation during the entire gestation period. The experimental groups were supplemented with Saline, C, and/or DHA, respectively, during the entire gestation (E0 to delivery). Results: Rat pups (n = 6/group) exposed to combined C and DHA showed significant improvement in birth weight, fur development, eye-opening as well as weight gain on the 7th, 14th, and 21st postnatal day and pinnae detachment (assessed from birth to postnatal day 21) when compared with age-matched NC, SC or C or DHA pups. Further, significant reflex responses were observed in visual placing and bar holding of pups exposed to both C and DHA, whereas the differences in surface righting, negative geotaxis, and grasping reflexes were not significant between the groups. Conclusion: Gestational supplementation of both C and DHA rather than either of them alone is better in enhancing developmental outcomes in rat pups.

• 한국수산과학회지
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• 제28권6호
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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.