• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.913-919
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• 2000

We give pressure stimulation into long chain fatty acid of LB thin films then manufacture a device under the accumulation condition that the state surface pressure is 20[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Arachidic acid/Al, the number of accumulated layers are 13, 17 and 19. The I-V characteristic of the device is measured from 0[V] to +1.5[V]. We have investigated the capacitance because this fatty acid system have a accumulated layers. The maximum value of measured current is increased as the number of accumulated layers are decreased. The capacitor properties of a thin film is better as the distance between electrodes is smaller. The results have shown the insulating materials and could control the conductivity by accumulated layers.

• Journal of Microbiology and Biotechnology
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• v.32 no.7
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• pp.949-954
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• 2022

The lipolytic yeast Candida aaseri SH14 contains three Acyl-CoA oxidases (ACOXs) which are encoded by the CaAOX2, CaAOX4, and CaAOX5 genes and catalyze the first reaction in the β-oxidation of fatty acids. Here, the respective functions of the three CaAOX isozymes were studied by growth analysis of mutant strains constructed by a combination of three CaAOX mutations in minimal medium containing fatty acid as the sole carbon source. Substrate specificity of the CaAOX isozymes was analyzed using recombinant C. aaseri SH14 strains overexpressing the respective genes. CaAOX2 isozyme showed substrate specificity toward short- and medium-chain fatty acids (C6-C12), while CaAOX5 isozyme preferred long-chain fatty acid longer than C12. CaAOX4 isozyme revealed a preference for a broad substrate spectrum from C6-C16. Although the substrate specificity of CaAOX2 and CaAOX5 covers medium- and long-chain fatty acids, these two isozymes were insufficient for complete β-oxidation of long-chain fatty acids, and therefore CaAOX4 was indispensable.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.22-28
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• 2003

Increasing conjugated linoleic acid (CLA) content in dairy products has been a research Interest due to the potential health benefits resulted from consuming CLA. Attempts were made to obtain high level natural CLA containing fatty acid fractions from milk fat through bovine feeding of sunflower oil (SO) and urea fractionation. SO feeding changed the fatty acid profile of milk fat. increasing the CLA content five-fold at eight weeks of trial. Milk fat obtained from S0-fed cows was hydrolyzed to free fatty acids, which were then fractionated with urea at various ratios. The profiles of fatty acids were also greatly influenced by urea fractionation. Long-chain unsaturated fatty acids, Including CLA, were concentrated in milk fat after the fractionation, whereas saturated long-chain counterparts were eliminated. The highest level of CLA was achieved by the fractionation at 2:1 urea/fatty acid ratio (UFR2). CLA level was elevated 2.5-fold, and the Cl8:1/C18:0 fatty acid ratio was increased 120 times after the fractionation. The level of CLA in high CLA-milk fat (24mg/g fat) obtained from the feeding study was further increased through urea fractionation up to 52mg/g fat, 10 folds as high as CLA in the control milk fat (5mg/g fat).

• Journal of Nutrition and Health
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• v.31 no.1
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• pp.88-95
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• 1998

Kong chain $\omega$3 & $\omega$6 fatty acids and taurine have been suggested to have structural and /or functional roles in the brain. The purpose of this study was to evaluate the changes in the percentage of fatty acids and taurine concentration in human milk obtained from Korean mothers(n=37) as lactation proceeds from birth to 5wks postpartum , and to determine the correlation between taurine concentration and fatty acid composition in breast milk. Level of fatty acids and taurine in breast milk were measured by GLC and HPLC, respectively. The percentages of medium -chain saturated fatty acids(10 : 0, 12 : 0 & 14: 0) were increased significantly , while percentages of long-chain saturated fatty acids(22 :0 & 24 : 0), and most of the long chain $\omega$6 and $\omega$3 fatty acids(20 : 3$\omega$6 , 20 :4$\omega$6, 22 :4$\omega$6 , 22 :5$\omega$6, 22 :5$\omega$3 & 22 : 6$\omega$3) were decreased significantly in mature milk (5 wks postpartum ) as compared to the colostrum. Taurine concentrations in colostrum and mature milk from Korean mothers were 549 $\pm$58 and 233 $\pm$41nmol/ml , respectively. Taurine concentrations in human milk was negatively correlated with the percentages of medium -chain saturated fatty acids ( 10 : 0 &12 : 0), and positively correlated with the percentages of long-chain saturated fatty acids( 16 :0, 20 : 0, 22 : 0& 24 : 0) and long-chain monounsaturated fatty acids( 20 : 1, 22 : 1 & 24 ; 1). Taurine concentration in human milk was positively correlated with elongation indices of both $\omega$6 and $\omega$3 fatty acids, and negatively correlated with the desaturation index of $\omega$6 fatty acids. These close relationships between fatty acids compositions and taurine level in human milk are worth pursing further investigation, especially with regard to their common roles in retina and brain development.

• Nutritional Sciences
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• v.1 no.1
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• pp.8-15
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• 1998

In order to independently examine the effects of long-chain saturated fatty acids and dietary cholesterol levels on plasma and hepatic cholesterol concentrations, six different diets were fed to male Mongolian gerbils (14 gerbils pes grcup) for an 8-week period. Purified diets contained 36% energy as fat (each saturated fatty acid tested comprised about 20% of the total fat energy) and 0.06% (w/w) cholesterol, corresponding to typical human consumption patterns in Western diets. Fat blends were formulated with natural fat sources. To determine the effects of different saturated fatty acids on plasma and liver cholesterol levels, four of the six diets contained constant levels of all nutrients except for the amounts of lauric acid (12 0), myristic acid (14 : 0), palmitic acid (16 0), and stearic acid (18 : 0). Dietary cholesterol effects were tested using 16 : 0-enriched diets containing 0, 0.006, and 0.06% (w/w) cholesterol. None of the plasma lipids were influenced by fatty acid treatment, including triglycerides, plasma total-, VLDL+LDL-, and HDL-cholesterol. However, hepatic esterified cholesterol concentrations were increased in the palmitic and stearic arid diet groups compared to the lauric and myristic acid diet group. The molar ratios of hepatic EC/FC were the highest in the palmitic acid diet (12.2 $\pm$0.6) and the lowest in the myristic acid diet (6.4$\pm$0.2). Dietary cholesterol significantly (p<0.001) increased the plasma total cholesterol which was due to the increase of both HDL-and VLDL+LDL-cholesterol. In the absence of dietary cholesterol and compared to other species, the gerbil exhibited a high molar ratio of hepatic EC/FC, which was funker elevated by dietary cholesterol feeding (0.06%). The results from this study indicate that hepatic cholesterol concentrations are sensitive to both low levels of dietary cholesterol and saturated fatty acid chain length and also, that plasma cholesterol concentrations are sensitive to low levels of dietary cholesterol .

• BMB Reports
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• v.28 no.3
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• pp.261-264
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• 1995

The lipids of a Korean native blood-sucking leech (Hirudo nipponia) were isolated and analyzed. Cholesterol, fatty acids, triglycerides, glycerylether diester and cholesteryl esters were found from epidennal extracts. The major fatty acids in the leech skin were $C_{16:0}$, $C_{18:0}$, $C_{20:1}$. $C_{20:3}$ components. These components were derived from cholesteryl esters, glycerides, fatty acids and other polar lipids. After 60 days fasting, cholesterol, fatty acids and triglycerides in the skin were reduced in number and the total fatty acid composition was changed slightly. The data of total fatty acids in fasted and fed leech showed that medium-chain fatty acids were more affected than long-chain fatty acids. Other trace fatty acids appeared to be decreased by fasting.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.700-704
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• 2013

A study was conducted to investigate the effects of feeding medium chain triacylglycerol (MCT) on growth performance, plasma fatty acids, villus height and crypt depth in preweaning piglets. A total of 150 new born piglets were randomly assigned into one of three treatments: i) Control (no MCT); ii) MCT with milk (MCT+milk); iii) MCT without milk (MCT+fasting). Body weight, plasma fatty acid profiles, villus height and crypt depth were measured. Final BW for the Control and MCT+fasting was lower (p<0.05) than MCT+milk. The piglets fed with MCT regardless of milk provision or fasting had greater medium chain fatty acids (MCFA) than the Control. In contrast, the Control had greater long chain fatty acid (LCFA) and unsaturated fatty acid (USFA) than the MCT piglets. The piglets fed with MCT regardless of milk provision or fasting had higher villus height for the duodenum and jejunum after 6 h of feeding. Similar observations were found in piglets fed with MCT after 6 and 8 days of treatment. This study showed that feeding MCT to the piglets before weaning improved growth performance, with a greater concentration of MCT in blood plasma as energy source and a greater height of villus in duodenum, jejunum and ileum.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1646-1652
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• 2016

Mammalian target of rapamycin complex 1 (mTORC1) is a central regulator of cell growth and metabolism and is sufficient to induce specific metabolic processes, including de novo lipid biosynthesis. Elongation of very-long-chain fatty acids 1 (ELOVL1) is a ubiquitously expressed gene and the product of which was thought to be associated with elongation of carbon (C) chain in fatty acids. In the present study, we examined the effects of rapamycin, a specific inhibitor of mTORC1, on ELOVL1 expression and docosahexaenoic acid (DHA, C22:6 n-3) synthesis in bovine mammary epithelial cells (BMECs). We found that rapamycin decreased the relative abundance of ELOVL1 mRNA, ELOVL1 expression and the level of DHA in a time-dependent manner. These data indicate that ELOVL1 expression and DHA synthesis are regulated by mTORC1 in BMECs.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.3
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• pp.414-421
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• 2014

This study was conducted to determine the effects of saturated long-chain fatty acids (LCFA) on cell proliferation and triacylglycerol (TAG) content, as well as mRNA expression of ${\alpha}s1$-casein (CSN1S1) and genes associated with lipid and protein synthesis in bovine mammary epithelial cells (BMECs). Primary cells were isolated from the mammary glands of Holstein dairy cows, and were passaged twice. Then cells were cultured with different levels of palmitate or stearate (0, 200, 300, 400, 500, and 600 ${\mu}M$) for 48 h and fetal bovine serum in the culture solution was replaced with fatty acid-free BSA (1 g/L). The results showed that cell proliferation tended to be increased quadratically with increasing addition of stearate. Treatments with palmitate or stearate induced an increase in TAG contents at 0 to 600 ${\mu}M$ in a concentration-dependent manner, and the addition of 600 ${\mu}M$ was less effective in improving TAG accumulation. The expression of acetyl-coenzyme A carboxylase alpha, fatty acid synthase and fatty acid-binding protein 3 was inhibited when palmitate or stearate were added in culture medium, whereas cluster of differentiation 36 and CSN1S1 mRNA abundance was increased in a concentration-dependent manner. The mRNA expressions of peroxisome proliferator-activated receptor gamma, mammalian target of rapamycin and signal transducer and activator of transcription 5 with palmitate or stearate had no significant differences relative to the control. These results implied that certain concentrations of saturated LCFA could stimulate cell proliferation and the accumulation of TAG, whereas a reduction may occur with the addition of an overdose of saturated LCFA. Saturated LCFA could up-regulate CSN1S1 mRNA abundance, but further studies are necessary to elucidate the mechanism for regulating milk fat and protein synthesis.