• 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 .

• 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.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.1
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• pp.15-20
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• 1982

The fatty acid composition of human milk was determined in 20 milk samples (ten colostrum and 10 mature) obtained at different stages of lactation. Human colostrum contained a lower percentage of total lipids than mature milk. In comparison with mature milk, human colostrum was characterized by a lower percentage of saturated fatty acids, a higher percentage of monounsaturated fatty acids and a higher percentage of extra-long-chain polyunsaturated fatty acid metabolites of both linoleic acid ($\omega$ 6 series) and linolenic acid ($\omega$ 3 series). The linoleic acid levels reported here are considerably higher than those reported previously in Korea. This shift has paralleled an increase in the use of vegetable oils in Korean diet. The human mature milk differed from marketing cow's milk in fatty acid composition, as it had a lower content of short-, medium-and long-chain saturated fatty acids and a higher content of long-chain monounsaturated and polyunsaturated fatty acids.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.204-208
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• 1999

Friction was measured on filter paper sheets impregnated with model compounds representing wood extractives using an apparatus based on the horizontal plane principle. The best lubrication of paper surfaces was achieved when they were completely separated by a densely packed film of saturated long-chain amphophilic molecules, such as fatty acids. The fatty acids adsorbed with their polar ends on the paper surface, causing their hydrocarbon chaine to be orientated perpendicularly to the paper surface. The saturated C18-acid, stearic acid, was an efficient lubricator for paper surfaces. The introduction of a double bond in stearic acid eliminated its lubricating ability. The spatial length of the lubricating fatty acid thereby decreases from 24${\AA}$ to 11${\AA}$. However the transisomer of oleic acid, elidic acid, had the ability to lower friction due to an increased spatial length of the fatty acid. Both the spatial length of the hydrocarbon chain and the number of lubricating chains may be of importance for the paper-to-paper friction caused by wood extractives. A hydrophilic head-graup in the wood extractive and an ordered molecular layer of lubricating molecules seems also to be prerequisites for efficient lubrication. A chemical weak boundary layer between the paper sheets was suggested to cause the low friction when long chain saturated fatty acids were deposited on paper.

• 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).

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.23-30
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• 2000

The effects of grass lipids and long chain fatty acids (LCFA; palmitic, stearic and oleic acids), at low concentrations (0.001~0.02%), on the growth and enzyme activity of two strains of anaerobic fungi, monocentric strain Piromyces rhizinflata B157 and polycentric strain Orpinomyces joyonii SG4, were investigated. The addition of grass lipids to the medium significantly (p<0.05) decreased filter paper (FP) cellulose digestion, cellulase activity and fungal growth compared to control treatment. However, LCFA did not have any significant inhibitory effects on fungal growth and enzyme activity, which, however, were significantly (p<0.05) stimulated by the addition of oleic acid as have been observed in rumen bacteria and protozoa. This is the first report to our knowledge on the effects of LCFA on the rumen anaerobic fungi. Continued work is needed to identify the mode of action of LCFA in different fungal strains and to verify whether these microorganisms have ability to hydrogenate unsaturated fatty acids to saturated fatty acids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.39-46
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• 1985

The fatty acid composition, total number of fatty acid acyl carbon atoms and species of triglycerides from human milk samples obtained during 70 days of lactation from 39 mothers were determined by argentation thin-layer and gas chromatographic procedures. The medium- and long-chain saturated fatty acids(8:0, 1O:0, 12:0 and 14:0) which are formed exclusively by synthesis within mammary gland increased significantly from colostrum to mature milk. Long-chain saturated fatty acids(16 : 0, 22 : 0 and 24: 0) were significantly higher than tile levels found in transitional and mature milk. The precursors of w C- and w 3-series, 18:2 w 6 and 18:3 w 3, were increased slightly in progressing lactation. Colostrum contained significantly higher proportions of 18:1 w 9 and w 6- and w 3- derived long-chain polyunsaturated fatty acids than transitional milk, and these levels were further reduced in mature milk. The triglycerides of human milk lipids which were made up of 30-60 acyl carbon atoms showed a pattern with major contributions made by the glycerides with 44-52 acyl carbon atoms. The levels of triglycerides with less than 46 acyl carbon atoms increased significantly with the elapse of lactation period, whereas those with more than 50 acyl carbon atoms decreased significantly. The fully saturated trig1ycerides increased significantly as the lactation proceeded, but the dienoic triglycerides declined significantly.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.251-253
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• 1984

A simple and modified method is developed to determine a lipase activity. A linear relationship exists between the color intensity and the free fatty acid liberated by enzyme action. The range of determination is from 0.05 to $1.5\;{\mu}moles$ of long chain fatty acid (oleic acid) and 0.2 to $2.0\;{\mu}moles$ of short chain fatty acid (caproic acid). The cumbersome procedure of the removal of the upper aqueous phase which was required in the previous copper soap extraction method was eliminated by the movement of solvent phase to upper phase in the respective biphasic system with a mixture solvent (chloroform: n-hexane:ethanol = 49:49:2) and copper reagent saturated with sodium chloride.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1522-1528
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• 2008

The morphogenetic behavior of a tropical marine Yarrowia lipolytica strain on hydrophobic substrates was studied. Media containing coconut oil or palm kernel oil (rich in lauric and myristic acids) prepared in distilled water or seawater at a neutral pH supported 95% of the cells to undergo a transition from the yeast form to the mycelium form. With potassium laurate, 51 % of the cells were in the mycelium form, whereas with myristate, 32% were in the mycelium form. However, combinations of these two fatty acids in proportions that are present in coconut oil or palm kernel oil enhanced the mycelium formation to 65%. The culture also produced extracellular lipases during the morphogenetic change. The yeast cells were found to attach to the large droplets of the hydrophobic substrates during the transition, while the mycelia were associated with the aqueous phase. The alkane-grown yeast partitioned more efficiently in the hydrophobic phases when compared with the coconut oil-grown mycelia. A fatty acid analysis of the mycelial form revealed the presence of lauric acid in addition to the long-chain saturated and unsaturated fatty acids observed in the yeast form. The mycelia underwent a rapid transition to the yeast form with n-dodecane, a medium-chain aliphatic hydrocarbon. Thus, the fungus displayed a differential behavior towards the two types of saturated hydrophobic substrates.