• 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 Microbiology and Biotechnology
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• v.31 no.1
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• pp.130-136
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• 2021

Persister cell formation and biofilms of pathogens are extensively involved in the development of chronic infectious diseases. Eradicating persister cells is challenging, owing to their tolerance to conventional antibiotics, which cannot kill cells in a metabolically dormant state. A high frequency of persisters in biofilms makes inactivating biofilm cells more difficult, because the biofilm matrix inhibits antibiotic penetration. Fatty acids may be promising candidates as antipersister or antibiofilm agents, because some fatty acids exhibit antimicrobial effects. We previously reported that fatty acid ethyl esters effectively inhibit Escherichia coli persister formation by regulating an antitoxin. In this study, we screened a fatty acid library consisting of 65 different fatty acid molecules for altered persister formation. We found that undecanoic acid, lauric acid, and N-tridecanoic acid inhibited E. coli BW25113 persister cell formation by 25-, 58-, and 44-fold, respectively. Similarly, these fatty acids repressed persisters of enterohemorrhagic E. coli EDL933. These fatty acids were all medium-chain saturated forms. Furthermore, the fatty acids repressed Enterohemorrhagic E. coli (EHEC) biofilm formation (for example, by 8-fold for lauric acid) without having antimicrobial activity. This study demonstrates that medium-chain saturated fatty acids can serve as antipersister and antibiofilm agents that may be applied to treat bacterial infections.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.354-358
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• 1999

In order to know the antifungal characteristics of saturated fatty acids having 6 to 12 carbons, their minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) were estimated against Saccharomyces cerevisiae. Fatty acids from C6 to C11 exhibited increasing activity with chain length, but C12 fatty acid did not show activity at all. In relation to antifungal modes of actions, fatty acids investigated showed on inhibitory activity toward the plasma membrane H+-ATPase of Saccharomyces cerevisiae. Their inhibitions to the glucose-induced acidification and ATP hydrolysis caused by the proton pump were found to be in common wiht antifungal activities. At the test concentration of 1mM, hexanoic acid (C6) showed the lowest inhibition of about 30%, while undecanoic acid(C11) showed the strongest inhibition of over 90%. In addition, as seen with antifungal activity, the inhibitory activity of dodecanoic acid (C12) was suddenly reduced to less than 50%.

• 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.

• 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 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.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.711-719
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• 2000

The characteristics of the exocrine pancreatic secretions in pigs and its hormonal regulation as influenced by dietary lipids are reviewed. There is clear evidence that the secretion of lipolytic enzymes is positively correlated with the amount of fat consumed by the pig. For example, there was an increase in the specific lipase activity by 83% after the dietary fat content was increased from 5% to 25%. Moreover, it was shown that also the quality of fat has an influence on exocrine pancreatic secretions. Peroxidized canola oil stimulated total lipase secretion much more than non-peroxidized oil. The influence of fatty acid composition on exocrine pancreatic secretions is discussed equivocally. Some authors showed that saturated fats stimulated the exocrine pancreatic secretions more than unsaturated. Others showed that the chain length of fatty acids had a strong influence on pancreatic secretions as well. Due to the different surgical methods used for sampling of pancreatic juice and wide variety of fats and oils used in these studies, direct comparisons between studies are extremely difficult to make. Plasma levels of hormones such as cholecystokinin (CCK), neurotensin (NT) and peptide YY (PYY) are influenced by the nutrient composition of the diet. With increasing amounts of fat present in the small intestine, the release of these hormones was stimulated. There is evidence that CCK release is dependent on the chain length of the fatty acids. Medium chain triglycerides stimulated the CCK release more than long chain triglycerides. Neurotensin was released more by unsaturated than by saturated fatty acids; similar results were observed for the PYY release. However, results are contradictory and further investigations are warranted that focus on the underlying mechanisms involved in the regulatory response of the exocrine pancreas to lipids of different origin.

• Journal of Nutrition and Health
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• v.26 no.6
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• pp.758-771
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• 1993

This study was conducted longitudinally following the total lipid and cholesterol content, fatty acids composition and Vitamin E content in human milk from 2-5 days to 12 weeks postpartum of 45 lactating Korean mothers. All samples were from well-defined subjects and uniform collection procedures were used. Total lipid concentration increased from 1.98g/dl at 2-5 days to 3.09g/dl at 12 weeks postpartum. However, there was a large variation in the concentration of total lipids. Total cholesterol concentration tended to decrease from 20.68mg/dl at 2-5days to 17.19mg/dl at 12 weeks. In comparison with transitional and mature milk, human colostrum was characterized by a lower percentage of saturated fatty acids including medium chain length fatty acids and a higher percentage of monounsatureated fatty acids and polyunsaturated fatty acids. Therefore, the P/S and M/S ratios of human milk lipids decreased significanlty during lactation. P/M/S ratio of colostrum changed from 0.38 : 0.84 : 1.00 at 2-5 days to 0.29 : 0.61 : 1.00 at 12 weeks of mature milk. Total tocopherol concentration decreased significantly from 833 ug/dl at 2-5 days to 300 ug/dl at 12 weeks.

• 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.