• Journal of Dairy Science and Biotechnology
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• v.27 no.2
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• pp.25-36
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• 2009

Trans fatty acids (TFAs), especially elaidic acid, formed during partial hydrogenation of vegetable oils have been shown to increase LDL-cholesterol (LDL-C) and decrease HDL-cholesterol (HDL-C), thereby increasing the LDL-C/HDL-C ratio and elevating the risk of cardiovascular disease. However, studies on the health effects of ruminant TFAs have suggested that these TFAs, which are primarily vaccenic acids, have no or inverse association with coronary heart disease. Thus, dietary recommendations or legislation for TFAs should consider the differences in the physiological effects of TFAs derived from various food sources. This present review recapitulates the progress in TFA research by analyzing recent epidemiological studies or intervention studies and comparing the cardiovascular health effects of industrially produced TFA and ruminant TFA.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.512-515
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• 2005

An in vitro study was conducted to determine the effect of C18-polyunsaturated fatty acid on direct incorporation into the rumen bacteria, bio-hydrogenation and production of CLA in vitro. Sixty milligrams of linoleic acid ($C_{18:2}$) or linolenic acid ($C_{18:3}$) were absorbed into the 0.5 g cellulose powder was added to the 150 ml culture solution consisting of 120 ml McDougall's buffer and 30 ml strained rumen fluid. Four uCi of 1-$^{14}C_{18:2}$ or 1-$^{14}C_{18:3}$ (1 uCi/15 mg each fatty acid) were also added to the corresponding fatty acids to estimate the direct incorporation into the bacterial lipids. The culture solution was then incubated anaerobically in a culture jar with stirrer at 39$^{\circ}C$ for 12 h. Ammonia concentration and pH of the culture solution were slightly influenced by the fatty acids. Amount of fatty acid incorporated into the bacteria was 1.20 mg and 0.43 mg/30 ml rumen fluid for $C_{18:2}$ and $C_{18:3}$, respectively during 12 h incubation. Slightly increased CLA (sum of cis-9, trans-11 and cis-10, trans-12 $C_{18:2}$) was obtained from the $C_{18:3}$ addition compared to that from $C_{18:2}$ after 12 h incubation in vitro.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.765-766
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• 2000

Cerebrosides were isolated from soybean, deunjang and chungkukjang and their constituents were investigated. The principal fatty acid of soybean cerebroside was 2-hydroxy-palmitic acid but chungkukjang cerebroside consisted palmitic acid, elaidic acid(trans 18:1), oleic acid and stearic acid. The only sugar in cerebrosides was glucose. TLC analysis of cerebroside hydrolysate elucidated soybean and chungkukjang had same sphingold bases, mainly dihydroxy bases, trans-4, trans-sphingadienine. But, alkali stable glycolipid fractions of chungkukjang and deunjang had $2{\sim}3$ different primary amines.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.1015-1024
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• 2007

Trans-fatty acids (TFAs) are defined as the sum of all unsaturated fatty acids that contain one or more non-conjugated double bonds in a trans configuration. Dietary trans- fatty acids originate from commercially hydrogenated oils and from dairy and meat fats. From the perspective of the food industry, partially hydrogenated vegetable oils are attractive because of their long shelf life, stability during deep-frying, and semisolidity, which can be customized to enhance the palatability of baked goods and fried foods. Although no definite differences have been documented so far between the metabolic and health effects of industrial and ruminant TFAs, the intake of industrially produced TFA has declined, and in Europe, the majority of TFAs are of ruminant origin. Due to the scientific evidence associating TFA intake with increased risk of coronary heart disease (CDH), the Korea Food and Drug Administration (KFDA) issued a final rule that requires the amount of trans fat present in foods to be declared on the nutrition label, by December 1, 2007. In addition, many food manufacturers who use partially hydrogenated oils in their products have developed, or are considering ways, to reduce or eliminate trans-fatty acids from certain food products.

• Food Science of Animal Resources
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• v.31 no.4
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• pp.580-587
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• 2011

In this study, the effects of gamma-irradiation (1, 2 and 4 kGy) on texture profiles, fatty acid composition, free amino acids and sensory evaluation of dry-fermented sausage were evaluated. The hardness and adhesiveness of irradiated samples were significantly lower (p<0.01) than that of the control, while the gumminess of samples irradiated with 2 and 4 kGy was higher than the other tested samples (p<0.01). The sample irradiated at 4 kGy had a higher saturated fatty acid (SFA) content (C14:0, C16:0, C18:0) and significantly lower (p<0.05) unsaturated fatty acid content (UFA) (C16:1, C18:1, C18:3), trans, n-3 and n-6 fatty acid than the non-irradiated sample. Gamma-irradiation resulted in an increase (p<0.05) in phosposerine, aspartic acid and glutamic acid and a decrease (p<0.05) in glutamic acid in free amino acids. For the samples irradiated at 4 kGy, the sulfur odor and fat pungent flavor were significantly higher (p<0.05) and the moldy odor and moldy flavor were significantly lower than the control sample. In conclusion, gamma-irradiation had a significant effect on the texture profiles, fatty acid composition and sensory evaluation of dry-fermented sausage.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.990-999
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• 2012

The microbial biosynthesis of fatty acid of lipid metabolism, which can be used as precursors for the production of fuels of chemicals from renewable carbon sources, has attracted significant attention in recent years. The regulation of fatty acid biosynthesis pathways has been mainly studied in a model prokaryote, Escherichia coli. During the recent period, global regulation of fatty acid metabolic pathways has been demonstrated in another model prokaryote, Bacillus subtilis, as well as in Streptococcus pneumonia. The goal of this study was to increase the production of long-chain fatty acids by developing recombinant E. coli strains that were improved by an elongation cycle of fatty acid synthesis (FAS). The fabB, fabG, fabZ, and fabI genes, all homologous of E. coli, were induced to improve the enzymatic activities for the purpose of overexpressing components of the elongation cycle in the FAS pathway through metabolic engineering. The ${\beta}$-oxoacyl-ACP synthase enzyme catalyzed the addition of acyl-ACP to malonyl-ACP to generate ${\beta}$-oxoacyl-ACP. The enzyme encoded by the fabG gene converted ${\beta}$-oxoacyl-ACP to ${\beta}$-hydroxyacyl-ACP, the fabZ catalyzed the dehydration of ${\beta}$-3-hydroxyacyl-ACP to trans-2-acyl-ACP, and the fabI gene converted trans-2-acyl-ACP to acyl-ACP for long-chain fatty acids. In vivo productivity of total lipids and fatty acids was analyzed to confirm the changes and effects of the inserted genes in E. coli. As a result, lipid was increased 2.16-fold higher and hexadecanoic acid was produced 2.77-fold higher in E. coli JES1030, one of the developed recombinants through this study, than those from the wild-type E. coli.

• Journal of the Korean Society of Food Culture
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• v.21 no.2
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• pp.166-170
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• 2006

Soybean oil (SBO) was carried out deodorization at 4 factors as controlled maximum deodorizing temperature (DT), vacuum degree (VD), cycle time (CT) and treating amount of stripping steam (TASS). The results were as follows, acid value (AV), peroxide value (PV) and trans fatty acid content (TFAC) in produced deodorized SBO. Obtained deodorized SBO at high DT had the lower AV, PV, but TFAC was increased relatively. A suitable level of VD and TASS was 4.0 torr and 2.0%(w/w), than the longer CT was appeared a superior quality level. As a result, the best deodorizing conditions in SBO for lower TFAC were maximum DT; $235^{\circ}C$, VD;4.0torr, CT; $14{\sim}15min$ and TASS; 2.0% (w/w). Deodorizing conditions for lower TFAC in deodorizing of SBO was the major factor, more than lower DT was difficult because of the others quality factors.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.311-316
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• 2007

Trans fatty acid components separated and quantified using a SP-2560 capillary column in a gas chromatograph (GC) with flame ionization detector (FID). Trans fatty acid and total fatty acid contents were measured in 21 corn oils. Ranges of values for trans fatty acid (tFAs) contents of total fat (as g/100g fatty acids) were com oils $0.65{\pm}0.31$. Corn oils were heated at $175{\pm}5^{\circ}C$ for 5mins $(0{\sim}15\;times)$. The contents of tFAs (g/100) were increased from 0.292 (0 time) to 2.585 (15 times) in com oil. When frying oils (15 times) were incubated at $20{\pm}5^{\circ}C$ for 150 days, the contents of tFAs (g/100g) were increased from 2.585 to 3.683 in com oil. The amounts of tFAs (g) per serving size of frying oils (15 times) were increased from 0.01 to 0.18 in corn oil. The levels of the 18:1 trans isomers increased significantly the time of reusing of com oil.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.1012-1022
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• 2020

Objective: Caseins and fatty acids of milk are synthesized and secreted by the epithelial cells of the mammary gland. All-trans retinoic acid (ATRA), an active metabolite of vitamin A, has been shown to promote mammary development. This study was conducted to determine the effect of ATRA on casein synthesis and fatty acid composition in MAC-T cells. Methods: MAC-T cells were allowed to differentiate for 4 d, treated with ATRA (0, 1.0, 1.5, and 2.0 μM), and incubated for 3 d. We analyzed the fatty acid composition, the mRNA expression of casein and fatty acid synthesis-related genes, and the phosphorylation of casein synthesis-related proteins of MAC-T cells by gas chromatography, quantitative polymerase chain reaction, and western blotting, respectively. Results: In MAC-T cells, ATRA increased the mRNA levels of α_S1-casein and β-casein, janus kinase 2 (JAK2) and E74-like factor 5 of the signal transducer and activator of transcription 5 β (STAT5-β) pathway, ribosomal protein S6 kinase beta-1 (S6K1) and eukaryotic translation initiation factor 4E binding protein 1 of the mammalian target of rapamycin (mTOR) pathway, inhibited the mRNA expression of phosphoinositide 3-kinase and eukaryotic initiation factor 4E of the mTOR pathway, and promoted the phosphorylation of STAT5-β and S6K1 proteins. Additionally, ATRA increased the de novo synthesis of fatty acids, reduced the content of long-chain fatty acids, the ratio of monounsaturated fatty acids to saturated fatty acids (SFA), the ratio of polyunsaturated fatty acids (PUFA) to SFA, and the ratio of ω-6 to ω-3 PUFA. The mRNA levels of acetyl-CoA carboxylase 1, fatty acid synthase, lipoprotein lipase, stearoyl-CoA desaturase, peroxisome proliferator-activated receptor gamma, and sterol regulatory element-binding protein 1 (SREBP1) were enhanced by ATRA. Conclusion: ATRA promotes the synthesis of casein by regulating JAK2/STAT5 pathway and downstream mTOR signaling pathway, and it improves the fatty acid composition of MAC-T cells by regulating SREBP1-related genes.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1363-1372
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• 2019

Objective: This study was designed to investigate the effect of diet supplementation with rubber seed oil and flaxseed oil on serum fatty acids profile, oxidation stability of serum and milk, and immune function of dairy cows. Methods: Forty-eight mid-lactation Holstein dairy cows were randomly assigned to one of four treatments for 8 wk, including basal diet (CON) or the basal diet supplemented with 4% rubber seed oil (RO), 4% flaxseed oil (FO) or 2% rubber seed oil plus 2% flaxseed oil (RFO) on a dry matter basis. Results: Compared with CON, all the oil groups increased the levels of trans-11 C18:1 (vaccenic acid), cis-9, trans-11 C18:2 (conjugated linoleic acid, CLA) and C18:3 (${\alpha}$-linolenic acid, ALA) in serum. Both the activity of glutathione peroxidase and catalase in serum and milk in oil groups were decreased, which were negatively correlated with the levels of cis-9, trans-11 CLA and ALA. The concentrations of proinflammatory factors (tumor necrosis factor ${\alpha}$ and interferon ${\gamma}$) in serum of oil groups were lower than that from the CON cows. Conclusion: These results indicate that diet supplementation with RO or FO could alter serum fatty acid profile and enhance the immune function of dairy cows. However, the negative effect on milk oxidation stability should be considered when feeding these n-3 polyunsaturated fatty acid-enriched oils in dairy production.