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Forsythe CE, French MA, Goh YK, Clandinin MT. Cholesterolaemic influence of palmitic acid in thesn-1, 3v.thesn-2 position with high or low dietary linoleic acid in healthy young men. Br J Nutr 2007; 98:337-44. [PMID: 17391563 DOI: 10.1017/s0007114507704993] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Healthy young men were fed four diets for 2 weeks each providing natural fats containing palmitic acid (16 : 0) predominantly in thesn-1, 3 position of dietary TAG or containing 16 : 0 predominantly in thesn-2 position with low or high levels of linoleic acid (18 : 2n-6). Two treatments supplied 16 : 0 in thesn-1, 3 positions from palmstearin with low (3 % energy) or high (>7 % energy) 18 : 2n-6 and two treatments supplied 16 : 0 in thesn-2 position from lard with high or low levels of 18 : 2n-6. Diets contained 30–35 % energy as fat, 7–11 % energy as 16 : 0 and moderate levels of cholesterol. Fasting serum cholesterol and lipoprotein concentrations were measured. Cholesterol fractional synthesis rate (FSR) was determined by2H incorporation. Diets providing 16 : 0 in thesn-2 position resulted in lower fasting serum total cholesterol (TC) and a lower TC:HDL ratio than diets providing 16 : 0 in thesn-1, 3 positions. Diets with high levels of 18 : 2n-6 significantly decreased the TC:HDL ratio, reaffirming the well-known cholesterol-reducing effect of 18 : 2n-6. A lower non-esterified cholesterol FSR was observed with low dietary levels of 18 : 2n-6. No differences between dietary treatments were found for serum HDL-cholesterol, LDL-cholesterol or TAG. It is concluded that dietary fats containing 16 : 0 in thesn-2 position may result in slightly lower fasting TC than diets providing 16 : 0 in thesn-1, 3 positions, while the level ofn-6 polyunsaturated fat influences endogenous cholesterol synthesis.
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Affiliation(s)
- C E Forsythe
- Alberta Institute for Human Nutrition, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Canada
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2
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Craven RJ, Lencki RW. Rapid analysis of acylglycerols in low molecular weight milk fat fractions. Lipids 2007; 42:473-82. [PMID: 17404768 DOI: 10.1007/s11745-007-3044-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Accepted: 02/21/2007] [Indexed: 11/26/2022]
Abstract
A suitable analytical method was required to facilitate development of an industrial-scale short-path distillation (SPD) process. Short-path distillation produces milk fat distillates (MFD) enriched in low molecular weight milk fat components-viz. free fatty acids, monoacylglycerols, diacylglycerols, cholesterol and low molecular weight triacylglycerols. In this case, solid-phase extraction (SPE) was considered a better alternative than thin-layer chromatography for separating polar and apolar lipid components in MFD samples due to its speed and near-complete recoveries. Solid-phase extraction of MFDs yielded two fractions, both of which are sufficiently pure for subsequent analysis by gas chromatography. This procedure provided rapid and complete chemical characterization (including mass balances) of low-molecular weight milk-fat fractions.
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Affiliation(s)
- R J Craven
- Department of Food Science, University of Guelph, N1G 2W1, Guelph, ON, Canada
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3
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Hui SP, Murai T, Yoshimura T, Chiba H, Nagasaka H, Kurosawa T. Improved HPLC assay for lipid peroxides in human plasma using the internal standard of hydroperoxide. Lipids 2005; 40:515-22. [PMID: 16094862 DOI: 10.1007/s11745-005-1412-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We have developed a sensitive reversed-phase chemiluminescence HPLC approach for simultaneous quantitative and qualitative analyses of hydroperoxides of cholesteryl ester and TG in human plasma. Standard hydroperoxides of cholesteryl ester and TG and a novel internal standard (1-tetradecanyl 3-octadecenoyloxy-5beta-cholan-24-oate monohydroperoxide) (I.S.) were chemically synthesized and the standard curves confirmed to be linear throughout the calibration range (1-1000 pmol). Within-day and between-day CV were less than 7%, and the recoveries were within the range of 84-93%. With sample size minimized to 0.1 mL of plasma for each run, plasma cholesteryl ester hydroperoxide levels were 189 +/- 87 nM (mean +/- SD) in healthy young (22-25 yr old; n = 15, male/female = 6:9) and 210 +/- 69 nM in healthy elderly (39-60 yr old; n = 6, male/female = 3:3). TG hydroperoxide was not detected in healthy subjects. In patients with advanced liver failure (36-67 yr old; n = 4, male/female = 2:2), hydroperoxide levels of plasma cholesteryl ester and TG were 11,903 +/- 9,553 nM and 3,318 +/- 1,590 nM, respectively, indicating an involvement of lipid oxidation. Sensitive and specific monitoring of plasma lipid peroxides using the present chemiluminescence HPLC approach with the synthesized I.S. may help our understanding of chemical and pathophysiological aspects of lipid peroxidation.
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Affiliation(s)
- Shu-Ping Hui
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Hokkaido 061-0293, Japan.
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Hui SP, Murai T, Yoshimura T, Chiba H, Kurosawa T. Simple chemical syntheses of TAG monohydroperoxides. Lipids 2004; 38:1287-92. [PMID: 14870933 DOI: 10.1007/s11745-003-1191-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
For the purpose of synthesizing standards to be used in the quantification of TAG hydroperoxides, three TAG (1,2-dioleoyl-3-palmitoylglycerol, 1-oleoyl-2-linoleoyl-3-palmitoylglycerol, and triolein) monohydroperoxides were chemically synthesized as authentic specimens. TAG were prepared by using a simple condensation in pyridine of glycerol and the corresponding acid chlorides. These TAG were then converted into monohydroperoxides by a photosensitized peroxidation. The synthesized monohydroperoxides were analyzed by normal-phase and RP-HPLC. The results of normal-phase HPLC analysis showed that monohydroperoxides from a corresponding TAG were a mixture of regioisomers. In RP-HPLC, however, the regioisomers of monohydroperoxides were not separated and gave a single peak, which may improve the sensitivity for the detection of TAG monohydroperoxides. In this study TAG monohydroperoxide standards were synthesized; these will be useful for the study of yet unknown biological and pathological roles of TAG hydroperoxides.
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Affiliation(s)
- Shu-Ping Hui
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
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Emken EA, Adlof RO, Duval SM, Shane JM, Walker PM, Becker C. Effect of triacylglycerol structure on absorption and metabolism of isotope-labeled palmitic and linoleic acids by humans. Lipids 2004; 39:1-9. [PMID: 15055228 DOI: 10.1007/s11745-004-1194-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effect of dietary TAG structure and fatty acid acyl TAG position on palmitic and linoleic acid metabolism was investigated in four middle-aged male subjects. The study design consisted of feeding diets containing 61 g/d of native lard (NL) or randomized lard (RL) for 28 d. Subjects then received an oral dose of either 1,3-tetradeuteriopalmitoyl-2-dideuteriolinoleoyl-rac-glycerol or a mixture of 1,3-dideuteriolinoleoyl-2-tetradeuteriopalmitoyl-rac-glycerol and 1,3-hexadeuteriopalmitoyl-2-tetradeuteriolinoleoyl-rac-glycerol. Methyl esters of plasma lipids isolated from blood samples drawn over a 2-d period were analyzed by GC-MS. Results showed that absorption of the 2H-fatty acids (2H-FA) was not influenced by TAG position. The 2H-FA at the 2-acyl TAG position were 85+/-4.6% retained after absorption. Substantial migration of 2H-16:0 (31.2+/-8.6%) from the sn-2 TAG position to the sn-1,3 position and 2H-18:2n-6 (52.8+/-6.4%) from the sn-1,3 position to the sn-2 position of chylomicron TAG occurred after initial absorption and indicates the presence of a previously unrecognized isomerization mechanism. Incorporation and turnover of the 2H-FA in chylomicron TAG, plasma TAG, and plasma cholesterol esters were not influenced by TAG acyl position. Accretion of 2H-16:0 from the sn-2 TAG position in 1-acylphosphatidylcholine was 1.7 times higher than 2H-16:0 from the sn-1,3 TAG positions. Acyl TAG position did not influence 2H-18:2n-6 incorporation in PC. The concentration of 2H-18:2n-6-derived 2H-20:4n-6 in plasma PC from subjects fed the RL diet was 1.5 times higher than for subjects fed the NL diet, and this result suggests that diets containing 16:0 located at the sn-2 TAG position may inhibit 20:4n-6 synthesis. The overall conclusion is that selective rearrangement of chylomicron TAG structures diminishes but does not totally eliminate the metabolic and physiological effects of dietary TAG structure.
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Affiliation(s)
- E A Emken
- USDA, ARS, NCAUR, Peoria, Illinois 61604, USA.
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Vieu C, Tercé F, Chevy F, Rolland C, Barbaras R, Chap H, Wolf C, Perret B, Collet X. Coupled assay of sphingomyelin and ceramide molecular species by gas liquid chromatography. J Lipid Res 2002. [DOI: 10.1016/s0022-2275(20)30157-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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8
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Panda SK, Broitman SA. An analytical method for the measurement of fecal neutral and acid sterols from rats with induced large bowel tumorigenesis. Anal Chim Acta 2001. [DOI: 10.1016/s0003-2670(00)01370-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Affiliation(s)
- R C Murphy
- Division of Cell Biology, National Jewish Medical and Research Center, 1400 Jackson Street, Denver, Colorado 80206, USA.
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10
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Quantitative determination of triacylglycerol profile of structured lipid by capillary supercritical fluid chromatography and high-temperature gas chromatography. J AM OIL CHEM SOC 1999. [DOI: 10.1007/s11746-999-0176-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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11
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Perona JS, Barrón LJ, Ruiz-Gutiérrez V. Determination of rat liver triglycerides by gas-liquid chromatography and reversed-phase high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 706:173-9. [PMID: 9551803 DOI: 10.1016/s0378-4347(97)00556-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Rats fed with a fat-free or an olive oil-rich diet were employed to compare the response of two chromatographic techniques in the determination of rat liver triglyceride (TG) molecular species composition. Gas-liquid chromatography (GLC) on polarizable liquid phase and reversed-phase high-performance liquid chromatography (RP-HPLC) have been commonly employed for TG analysis, obtaining a similar number of chromatographic peaks when used for animal tissue TG determination. In the present study similar results were achieved with regard to most relevant chromatographic peaks, however, important differences were found in the content of minor TGs. Indeed, RP-HPLC permitted separation of long chain polyunsaturated fatty acids, which were not detected by GLC, while the latter technique reported a higher number of myristoyl-containing TG species. RP-HPLC analysis reported a greater number of TGs, with more similarity to a random composition, made up from the liver fatty acid composition. Therefore, it was concluded that utilization of both techniques would be helpful for liver TG analysis as the use of only one of them does not provide a complete profile of liver TGs. Nevertheless RP-HPLC seems to be more useful for this purpose since revealed a more extensive profile.
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Affiliation(s)
- J S Perona
- Instituto de la Grasa, (C.S.I.C.), Seville, Spain
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12
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Evershed RP. High-resolution triacylglycerol mixture analysis using high-temperature gas chromatography / mass spectrometry with a polarizable stationary phase, negative ion chemical ionization, and mass-resolved chromatography. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 1996; 7:350-361. [PMID: 24203361 DOI: 10.1016/1044-0305(95)00701-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/1995] [Revised: 10/12/1995] [Accepted: 11/09/1995] [Indexed: 06/02/2023]
Abstract
High-temperature gas chromatography/mass spectrometry (HT-GC/MS) has been employed to study the behavior of mixtures of triacylglycerol molecular species on a polarizable stationary phase (immobilized 65% phenyl methyl silicone). The use of negative ion chemical ionization (NICI) at an ion source block temperature of 300 °C overcomes problems with interpretation of electron ionization (EI) mass spectra produced during the HT-GC/MS. The NICI spectra of triacylglycerols produced under these conditions contain abundant [RCO2](-), [RCO2 - 18](-), and [RCO2 - 19](-) ions, believed to be produced by nucleophilic gas-phase ammonolysis, that are used to identify the individual fatty acid moieties associated with peaks in triacylglycerol total ion chromatograms. The polarizable stationary phase produces significantly enhanced resolution of triacylglycerol molecular species compared to hightemperature stable apolar stationary phases, such as immobilized dimethyl polysiloxanes. The resolution of complex natural mixtures of triacylglycerols can be further improved by use of the Biller-Biemann enhancement technique to produce mass-resolved chromatograms. Investigation of the mass-resolved chromatograms provides important information with regard to the factors that affect elution orders of individual triacylglycerol molecular species. The analysis of mixtures of authentic triacylglycerols by HT-GC/MS via NICI provides data that relate to the analytical limits of the technique for the analysis of triacylglycerols that bear both saturated and polyunsaturated fatty acyl moieties.
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Affiliation(s)
- R P Evershed
- School of Chemistry, University of Bristol, Cantock's Close, BS8 1TS, Bristol, UK
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13
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Ruiz-Gutiérrez V, Barron LJ. Methods for the analysis of triacylglycerols. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1995; 671:133-68. [PMID: 8520690 DOI: 10.1016/0378-4347(95)00093-x] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This article discusses the methods most commonly employed in the analysis of the triacylglycerols (TAGs) in natural fats and considers the main advantages and disadvantages of each and the techniques for optimising analytical conditions. Complete analysis of the composition of a natural fat calls for a method of extracting and purifying the triglyceride fraction, normally by preparatory thin-layer and column chromatography. Determination of the individual components of triglyceride mixtures still entails certain difficulties, namely, the separation and identification of the TAGs in natural fats. High-performance liquid chromatography (HPLC) offers significant advantages over gas and thin-layer chromatography. Many workers have developed non-aqueous, reversed-phase HPLC systems capable of successfully resolving complex mixtures of TAGs, and combining reversed-phase (RP) HPLC and argentation chromatography may improve the results. Identification of the TAGs separated by HPLC becomes an extremely complex task if many different fatty acids are involved and if the sn-stereoscopic positions on the glycerol are to be determined. Enzymatic analysis and chiral-phase chromatography are capable of localising fatty acids on the TAG molecule. In closing, some of the most interesting biomedical applications of TAG analysis are summarised.
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14
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Hoving EB. Chromatographic methods in the analysis of cholesterol and related lipids. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1995; 671:341-62. [PMID: 8520700 DOI: 10.1016/0378-4347(95)00223-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Methods using thin-layer chromatography, solid-phase extraction, gas chromatography, high-performance liquid chromatography and supercritical fluid chromatography are described for the analysis of single cholesterol, esterified and sulfated cholesterol, and for cholesterol in the context of other lipid components, like other sterols and lipid classes. In connection with these techniques several clinical applications are mentioned.
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Affiliation(s)
- E B Hoving
- Central Laboratory for Clinical Chemistry, University Hospital Groningen, Netherlands
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15
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Adosraku RK, Choi GT, Constantinou-Kokotos V, Anderson MM, Gibbons WA. NMR lipid profiles of cells, tissues, and body fluids: proton NMR analysis of human erythrocyte lipids. J Lipid Res 1994. [DOI: 10.1016/s0022-2275(20)39939-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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16
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Ruíz-Gutiérrez V, Prada JL, Pérez-Jiménez F. Determination of fatty acid and triacylglycerol composition of human very-low-density lipoproteins. JOURNAL OF CHROMATOGRAPHY 1993; 622:117-24. [PMID: 8150860 DOI: 10.1016/0378-4347(93)80257-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The fatty acid composition of human very-low-density lipoproteins (VLDL) was studied in a population from western Andalusia with a diet in which the fat content came mainly from olive oil. The lipid composition of VLDL, including the fatty acid composition of the phospholipids and triacylglycerols, was examined by capillary gas chromatography. Twenty-five peaks were resolved, ranging in chain length from 14 to 24 carbon atoms, including geometric and positional isomers. The major fatty acids present in phospholipids were 16:0, 18:0, 18:1(n - 9) and 18:2(n - 6), and in triacylglycerols were 18:1(n - 9), 16:0 and 18:2(n - 6). The major triacylglycerol was POO, followed by PLO and OOO. MLP, PPS and LLL were absent. The presence of a large amount of OOO in this fraction demonstrates that the triacylglycerol composition of the VLDL depends on the type of diet consumed.
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Quantitation of plasma lipids by gas-liquid chromatography on high temperature polarizable capillary columns. J Lipid Res 1993. [DOI: 10.1016/s0022-2275(20)39688-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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18
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Monsma CC, Ney DM. Interrelationship of stearic acid content and triacylglycerol composition of lard, beef tallow and cocoa butter in rats. Lipids 1993; 28:539-47. [PMID: 8355579 DOI: 10.1007/bf02536086] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We investigated modes whereby stearic acid (18:0) exerts a neutral or cholesterol-lowering effect using dietary fats which provided graded levels of 18:0 and distinct triacylglycerol (TAG) profiles. Male Sprague-Dawley rats (150-175 g) were fed diets containing 0.2% cholesterol and 16% fat from corn oil, or from 1% corn oil plus 15% lard (13.2% 18:0), beef tallow (19.2% 18:0) or cocoa butter (34.7% 18:0) for 3 wk, and then killed in a fasted or fed state. Chylomicron (CM) fatty acid profiles suggested reduced absorption of 18:0 with greater 18:0 intake. CM TAG profiles indicated a reduction or loss of two TAG species compared to the TAG profiles of the stearate-rich diets: 1-palmitoyl-2-oleoyl-3-stearoyl glycerol (POS) and 1,3-distearoyl-2-oleoyl glycerol (SOS). Hepatic total cholesterol concentrations were 54-77% lower (P < 0.01) in the cocoa butter-fed than the lard-and beef tallow-fed groups. The cocoa butter group showed a significantly lower ratio of high-density lipoprotein esterified/free cholesterol than all other groups. Hepatic stearoyl-CoA and oleoyl-CoA concentrations, the substrate and product for hepatic delta 9 desaturase, were not significantly different for corn oil-fed and cocoa butter-fed groups in spite of a large difference in 18:0 intake. These data suggest that the neutral or cholesterol-lowering effect of 18:0 is not due to hepatic conversion of stearic to oleic acid, and that POS and SOS are poorly absorbed from stearate-rich dietary fats.
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Affiliation(s)
- C C Monsma
- Department of Nutritional Sciences, University of Wisconsin, Madison 53706
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Kuksis A, Myher JJ, Geher K, Breckenridge WC, Feather T, McGuire V, Little JA. Gas chromatographic profiles of plasma total lipids as indicators of dietary history. Correlation with carbohydrate and alcohol intake based on 24-h dietary recall. JOURNAL OF CHROMATOGRAPHY 1992; 579:13-24. [PMID: 1447339 DOI: 10.1016/0378-4347(92)80358-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Quantitative gas chromatographic estimates of the major lipid classes and molecular species in fasting plasma were correlated with total carbohydrate, starch, fibre, sucrose and alcohol intake based on 24-h dietary recall. Spearman coefficients (rs) and tests of significance (P) were obtained for groups of 775 males and 471 females aged 20-59 years from a Toronto-McMaster Lipid Research Clinics Population Study. The most significant correlations varying from rs 0.1 to 0.2 and P 0.001 to 0.0005 (n = 400-773) were between increased intake of alcohol and increased ratios of C50/C54 triacylglycerols, C34/C36 phosphatidylcholines and phosphatidylcholine/free cholesterol (PC/FC) of plasma. Increase in total dietary carbohydrate, starch and fibre correlated with decreasing C50/C54 triacylglycerol, C34/C36 phosphatidylcholine and PC/FC ratios (rs = -0.1-0.2; P less than 0.002-0.04; n = 400-773). In contrast, consumption of high levels of alcohol was associated with increasing C50/C54 triacylglycerol, C34/C36 phosphatidylcholine and PC/FC ratios. A high intake of alcohol (50-150 ml per day) distinguished itself from other simple carbohydrate-induced lipid profiles by its marked effect on increased C50/C52 triacylglycerol and PC/FC ratio.
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Affiliation(s)
- A Kuksis
- Banting and Best Department of Medical Research, University of Toronto, Canada
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Pchelkin V, Vereshchagin A. Reversed-phase thin-layer chromatography of diacylglycerols in the presence of silver ions. J Chromatogr A 1992. [DOI: 10.1016/0021-9673(92)85363-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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Chapter 15 Lipids. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/s0301-4770(08)61508-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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22
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Deuteration as an aid to the high-temperature gas chromatography—mass spectrometry of steryl fatty acyl esters. J Chromatogr A 1992. [DOI: 10.1016/0021-9673(92)85394-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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23
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Chen ZY, Yang JL, Menard CR, Cunnane SC. Linoleoyl-enriched triacylglycerol species increase in maternal liver during late pregnancy in the rat. Lipids 1992; 27:21-4. [PMID: 1608298 DOI: 10.1007/bf02537053] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In view of the previously reported changes in the fatty acid composition of maternal liver triacylglycerols in late pregnancy, changes in the composition of maternal liver triacylglycerol species were assessed in rats fed a semi-purified diet during pregnancy. Between day 18 and day 21 of pregnancy, total maternal liver triacylglycerols increased by 50%. Triacylglycerol species with a total acyl carbon number (C) of 50 or 60 (C50, C60) remained unchanged while C48 and C52-C58 were relatively increased. The individual triacylglycerol species containing one, two or three linoleoyl moieties were incompletely recovered using a polar high temperature gas-liquid chromatography (GLC) column. Nevertheless, at day 21 compared to day 18, the linoleoyl-containing species were relatively increased by 62-463%, while tripalmitin was decreased by 38%. Our data suggest that despite an adequate intake of linoleic acid (25 g/kg in the diet), maternal hepatic triacylglycerol content of linoleic acid decreased during mid-pregnancy but increased significantly toward term possibly in preparation for the transfer of linoleic acid to the neonate during lactation.
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Affiliation(s)
- Z Y Chen
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
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24
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Chen ZY, Cunnane SC. Short-term energy deficit causes net accumulation of linoleoyl-enriched triacylglycerols in rat liver. FEBS Lett 1991; 280:393-6. [PMID: 2013343 DOI: 10.1016/0014-5793(91)80339-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Energy depletion by reduced food intake over 4 days resulted in a 73% reduction in total rat liver triacylglycerols (TG). In liver TG of energy-depleted rats, dilinoleoyl oleoyl glycerol (OLL) and trilinoleoyl glycerol (LLL) were quantitatively increased by 85% and 147%, respectively. The net increase in linoleoyl-enriched species could be quantitatively accounted for by the release of linoleate from monolinoleoyl species and its subsequent reacylation into dilinoleoyl species and trilinolein during energy depletion. Hence while palmitate, oleate and some linoleate are being hydrolyzed, presumably for oxidation, some linoleate is retained and contributes to the remodelling of hepatic triacylglycerols during energy deficit.
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Affiliation(s)
- Z Y Chen
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
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25
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Kuksis A, Myher JJ, Geher K, Breckenridge WC, Feather T, McGuire V, Little JA. Gas chromatographic profiles of plasma total lipids as indicators of dietary history. Correlation with fat intake based on 24-h dietary recall. JOURNAL OF CHROMATOGRAPHY 1991; 564:11-26. [PMID: 1860906 DOI: 10.1016/0378-4347(91)80066-l] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Fasting plasma total lipid profiles were determined by high-temperature gas chromatography on a total of 1246 free living urban subjects, ages 20-59 years, from the Toronto-McMaster Lipid Research Clinic Population Study. Quantitative estimates of the major molecular species, lipid classes and lipid class ratios were correlated with a total of twelve dietary lipid components, including total saturated and unsaturated fats. oleic and linoleic acids, and cholesterol, to give appropriate Spearman coefficients (rS) and tests of significance (P) for groups of 775 males and 471 females. The intake of the various nutrients was derived from a 24-h dietary recall. The most significant correlations varying from rs +/- 0.1-0.4 and P less than 0.0001-0.0005 were between the intake of total fat, individual saturated and unsaturated fats, and the ratios of C50/C54 triacylglycerols and the C34/C36 phosphatidylcholines, which reflected the nature and quantity of the dietary fat consumed. Increases in dietary cholesterol and saturated fat produced small increases in plasma cholesterol and saturated triacylglycerols, while unsaturated dietary fat produced small decreases in saturated and increases in unsaturated plasma triacylglycerols. These changes in the plasma lipid parameters are consistent with those observed previously in much more limited dietary experiments with accurately known composition of ingested fats. It is, therefore, concluded that direct gas chromatographic profiling of plasma total lipids provides a simple and rapid method of verifying the overall correctness of the dietary recall.
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Affiliation(s)
- A Kuksis
- Banting and Best Department of Medical Research, University of Toronto, Ontario, Canada
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Kuksis A, Marai L, Myher JJ. Plasma lipid profiling by liquid chromatography with chloride-attachment mass spectrometry. Lipids 1991; 26:240-6. [PMID: 2046492 DOI: 10.1007/bf02543979] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A sensitive high-performance liquid chromatographic assay was developed using chloride attachment negative chemical ionization mass spectrometry for detection of glyceryl esters and ceramides, and positive chemical ionization mass spectrometry for detection of free cholesterol and cholesteryl esters in minimal quantities of plasma. The novel technique was validated by high temperature gas-liquid chromatography with flame ionization detection. Sample preparation was achieved by phospholipase C digestion of whole plasma, total lipid extraction and derivatization of any free carboxyl and hydroxyl groups by trimethyl- or tert-butyldimethyl-chlorosilane. The lipids were separated by reverse phase HPLC with 20-90% propionitrile in acetonitrile containing 1% dichloromethane, which served as the reagent and the source of chloride. Negative chemical ionization with chloride attachment is estimated to provide about 100 times higher response for the triacylglycerols and the trimethylsilyl or tert-butyldimethylsilyl ethers of diacylglycerols, and about 500 times higher response for the trimethylsilyl or tert-butyldimethylsilyl ethers of ceramides than positive chemical ionization mass spectrometry. Determination of the full negative chemical ionization mass spectra showed that each glycerolipid and ceramide species yielded a single ionic species corresponding to the chloride-attachment product of the parent ion. The cholesteryl esters and ethers failed to attach chloride and remained undetected by negative chemical ionization. However, the cholesteryl esters and ethers gave a high response for the steroid nucleus in positive chemical ionization mass spectrometry. Chloride attachment negative chemical ionization mass spectrometry is suitable for the unequivocal identification of plasma glycerolipids and ceramides in high-performance liquid chromatography and for the quantitation of molecular species in any unresolved peaks following appropriate calibration of the instrument response.
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Affiliation(s)
- A Kuksis
- Banting and Best Department of Medical Research, University of Toronto, Canada
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