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1.
U. Stoll 《European Journal of Lipid Science and Technology》1995,97(5):190-194
A Comparison of Phospholipids in Human Sera with Phospholipids in HDL-Fractions The phospholipid composition of human sera and HDL-fractions was analyzed and characterized. The phospholipids were extracted with Extrelut (Merck) according to the manufacturer's recommendation. The recovery of phospholipids (expressed as Pi before and after passage through the elution-column) was rather poor for sera (25%) and distinctly better for HDL-fractions (46%). Phosphatidylcholine is the main phospholipid in human sera and in a similar manner in the HDL-fraction. The fatty acid distribution of phosphatidylcholine in both fractions was assessed and the fatty acids in sn2-position were evaluated after hydrolysis with phospholipase A2. The fatty acid profile for native lysophosphatidylcholine, extracted from sera, was compared to the fatty acid distribution of lysolecithin formed from lecithin of sera after hydrolysis with phospholipase A2. Both lysolecithins differed distinctly in their fatty acid distribution. Phosphatidylcholine from sera was identical with phosphatidylcholine from the HDL-fractions concerning the fatty acid distribution and their positional isomerism. The small recovery of phospholipids after passage through an Extrelut-column is due to the strong protein-phospholipid interaction in sera and HDL-fractions. 相似文献
2.
Randall Wood 《Lipids》1975,10(12):736-745
Individual phospholipid classes derived from hepatoma, host liver, and normal liver of rats maintained on chow and fat free diets were examined in detail and the sphingomyelin and phosphoglyceride structures compared. The concentration of hepatoma spingomyelin was higher while phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, and diphosphatidylglycerol were only one-fourth to one-half normal liver concentrations, irrespective of diet. Hepatoma phosphatidylcholine, phosphatidylethanolamine, phosphatidyl-serine, and phosphatidylinositol contained higher percentages of 18:1 and, except phosphatidylinositol, much lower percentages of most polyunsaturated fatty acids than liver. The 1-position of host liver phosphatidylcholine and phosphatidylethanolamine, normal liver phosphatidylcholine and phosphatidylethanolamine, and hepatoma phosphatidylcholine from animals on both diets had the same approximate fatty acid composition, but the percentage of 16:0 in hepatoma phosphatidylethanolamine was reduced dramatically. The low percentage of 16:0 at the 1-position of both phosphatidylethanolamine and triglycerides suggests that the 1-position fatty acids of these two classes may have a similar origin. The fat free diet reduced the percentage of 18:2 in liver diphosphatidylglycerol 3-fold and the decrease was offset by increased percentages of 16:1 and 18:1; whereas the very low percentage of 18:2 in hepatoma diphosphatidylglycerol was offset by increased percentages of 18:0 and 16:0. Liver phosphatidylinositol and phosphatidylcholine from the animals fed the fat free diet contained the highest percentage of 20:3, which replaced 20:4. Hepatoma sphingomyelin contained a much higher concentration of 24:0 and 24:1 than liver. The hepatoma sphingomyelin also contained a C-24 dienoic acid, which was not detected in host and normal liver. Host liver contained a higher percentage of 22:6 than normal liver. The diglycerides derived from host liver PC contained a significantly higher percentage of carbon number 38 than normal liver. Diglycerides derived from hepatoma phosphatidylcholine and phosphatidylethanolamine exhibited a 1-random-2-random distribution of fatty acids, whereas diglycerides from liver phosphatidylcholine and phosphatidylethanolamine showed pairing of specific fatty acids. 相似文献
3.
Plaques and white matter from brains of multiple sclerosis (MS) patients were analyzed for lipid content, class composition,
and fatty acid composition of total lipid, together with the fatty acid composition of plaque glycerophospholipids, and the
results were compared with white matter from normal brain. Plaques contained less than 30% of the lipid present in normal
white matter. Plaque lipid was characterized by significantly increased proportions of glycerophospholipids and decreased
cerebrosides and sulfatides. In addition, a subacute plaque contained approximately 10 times the proportion of steryl esters
observed in chronic plaques or normal white matter. Total lipid from all the MS plaques showed significantly increased percentages
of saturated fatty acids, n−6, n−3 and total polyunsaturated fatty acids and decreased percentages of monoenes and alk-1-enyl
ethers in comparison with normal brains. These results were consistent with increased cellularity and astrogliosis associated
with MS plaques. However, analysis of plaque glycerophospholipids showed that the fatty acid changes observed in total lipid
were not simply due to the increased proportion of glycerophospholipids and decreased myelin lipids, but that the fatty acid
composition of the individual glycerophospholipids was different. 相似文献
4.
Lipid and fatty acyl composition of rat brain capillary endothelia isolated by a new technique 总被引:7,自引:0,他引:7
A method is described for the isolation of pure capillary endothelia from rat brain and the phospholipid composition of these
cells is reported. This method is rapid and requires only a small amount of starting material. It involves: (a) tissue disruption
by high speed homogenization, (b) separation of the capillary endothelia from other brain structures using sucrose gradients,
and (c) a final purification using a glass bead column. Choline and ethanolamine phosphoglycerides were found to be the predominant
lipid classes of these cells amounting to 31.9% and 24.4%, respectively, of total phospholipids. The choline phosphoglycerides
consisted almost exclusively of 1,2-diacyl glycerophosphorylcholine, whereas the ethanolamine phosphoglycerides consisted
of approximately equal amounts of 1,2-diacyl and 1-alk-l’-enyl-2-acyl glycerophosphorylethanolamine. The composition of the
constituent fatty acids of both choline and ethanolamine phosphoglycerides and the alk-1-enyl composition of ethanolamine
phosphoglycerides is reported. Saturated fatty acids accounted for 45% of the total fatty acids in choline phosphoglycerides
and for 53% in ethanolamine phosphoglycerides. Arachidonic acid accounted for approximately 48% of the total fatty acids in
alk-1-enyl ethanolamine phosphoglyceride. 相似文献
5.
The triacylglycerols of very low density lipoproteins (VLDL) and of chylomicrons were analyzed in the fasting and postabsorptive
states from normolipemic subjects and patients with Frederickson's Type II hyperlipoproteinemia, who subsisted on free choice
diets, standard diets excluding lard, or were given a breakfast enriched in lard. The VLDL and chylomicrons were obtained
by conventional ultracentrifugation, and the triacylglycerols were isolated by thin-layer chromatography (TLC). Representative
sn-1,2, 2n-2-3- and sn-1,3-diacylglycerols were generated by partial Grignard degradation of the triacylglycerols and a stereospecific
hydrolysis by phospholipase C of the mixed sn-1,2(2,3)-diacyl phosphatidylcholines prepared as intermediates. Representative
sn-2-acylglycerols were obtained by hydrolysis with pancreatic lipase. Positional distribution of the fatty acids was established
by subtracting in turn the fatty acid composition of the sn-2-position from the fatty acid composition of the sn-1,2- and
sn-2,3-diacylglycerols. The molecular association of the fatty acids in the diacylglycerol moieties was determined by gas-liquid
chromatography with mass spectrometry (GC/MS) of the tertiary-butyldimethylsilyl (t-BDMS) ethers. The molecular association
of the fatty acids in the triacylglycerols was determined by 1-random 2-random 3-random calculation following experimental
validation of the distribution. The results confirm a marked asymmetry in the positional distribution of the fatty acids in
all triacylglycerol samples, with the palmitic acid predominantly in the sn-1-position, the unsaturated acids about equally
divided between the sn-2-and sn-3-positions, and the stearic acid divided about equally between the sn-1- and sn-3-positions.
The overall structure of the VLDL and chylomicron triacylglycerols from patients and control subjects was characterized by
a noncorrelative distribution of fatty acids under all dietary conditions. 相似文献
6.
Trinidad Prez‐Palacios Teresa Antequera Elena Muriel Jorge Ruiz 《European Journal of Lipid Science and Technology》2006,108(10):835-841
The fatty acid and dimethyl acetal (DMA) compositions of the sn‐1 and the sn‐2 positions from individual phospholipid (PL) classes [phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI)], obtained from the Longissimus dorsi muscle of rat were studied. The profile of fatty acids and DMA in the sn‐1 and sn‐2 positions of all the PL classes showed marked differences. Overall, saturated fatty acids and monounsaturated fatty acids were in a higher proportion in the sn‐1 position than in the sn‐2 one, while polyunsaturated fatty acids were mainly in the sn‐2 position. Significant differences in the DMA and fatty acid compositions between individual PL classes for each position were found. PC contained the highest proportion of palmitic acid (16:0) in the sn‐1 position and of linoleic acid (18:2 n‐6) in the sn‐2 one. The highest values for stearic acid (18:0) and DMA in the sn‐1 position and for docosahexaenoic acid (22:6 n‐3) in the sn‐2 position were found in PE. PS and PI showed the highest proportion of oleic acid (18:1 n‐9) in the sn‐1 position and of arachidonic acid (20:4 n‐6) in the sn‐2 position. 相似文献
7.
On day seven of gestation, Wistar rats were assigned to a high essential fatty acid (EFA), low EFA, or a fat free diet. The
same diets were continued during lactation. On weaning, the offspring were fed the same diets as their mother. Rats were killed
at 222 days, brain capillary endothelia isolated, and total lipids extracted from the purified capillaries. The composition
of the constituent fatty acids of ethanolamine glycerophospholipid (EGP), choline glycerophospholipid (CGP), and the alk-1-eny
EGP composition from each diet is reported. A decrease in dietary EFA led to reduced proportions of total saturated acyl groups
in EGP with no change observed in the total saturated acyl groups from CGP, and an increase in monoenoic fatty acids, particularly
18∶1n−9 for each phospholipid class. The proportions of 20∶4n−6 in alk-1-enyl EGP were reduced in fat-free fed animals. In
addition, the relationship between 20∶3n−9 and 20∶4n−6 fatty acids in brain capillary endothelia were markedly increased with
a reduction in dietary fat. Low EFA and fat deficient animals showed a tendency to sequester 22∶6n−3. 相似文献
8.
The composition and positional distribution of fatty acids in phospholipids isolated from four locations of a hog carcass
is presented. Variations in fatty acid composition of phospholipids were found depending upon the location in the carcass.
The total unsaturated fatty acid content averaged 34.3 mole % for lecithin, 52.5 mole % for phosphatidylethanolamine, 40.3
mole % for phosphatidylserine and 41.3 mole % in sphingomyelin. The cephalins had a much higher percentage of polyunsaturated
fatty acids than lecithin. The chief saturated fatty acid in lecithin and sphingomyelin was palmitic and in cephalins it was
stearic. A snake venom enzyme preparation(Crotalus adamanteus) hydrolyzed primarily unsaturated fatty acids in phosphoglycerides and the higher the percentage of unsaturation within the
fatty acid the higher percentage of hydrolysis occurred. The unsaturated fatty acids were found chiefly at the theβ-position and the saturated fatty acids at thea-position in the phosphoglycerides.
Michigan State Agricultural Experiment Station Publication No. 3389.
Supported by the U.S. Public Health Service Research Grant No. GM 08801-03. 相似文献
9.
W. Van Pee J. Van Hee L. Boni A. Hendrikx 《Journal of the American Oil Chemists' Society》1979,56(10):901-903
The distribution of fatty acids between the sn-1-, sn-2- and sn-3-positions of the triglycerides from the oils of eight African
peanut varieties has been determined. The saturated fatty acids and eicosenoic acid occur almost exclusively at the sn-1-
and sn-3-positions. The sn-1-position contained slightly more palmitic acid than the sn-3-position. The fatty acids with a
chain length exceeding 18 carbons were preferentially incorporated in the sn-3-position. Linoleic acid was preferentially
esterified at the sn-2-position, whereas oleic acid was equally distributed among the three positions. The amount of the saturated
fatty acids, i.e., palmitic and stearic acid, and of oleic acid and linoleic acid incorporated in the sn-1-, sn-2-and sn-3-position,
were each linearly related to their respective content in the triglycerides. 相似文献
10.
Peter W. Parodi 《Lipids》1982,17(6):437-442
Milk triglycerides from the echidna, koala, Tammar wallaby, guinea pig, dog, cat, Weddell seal, horse, pig and cow were subjected
to fatty acid and stereospecific analysis to determine the positional distribution of the fatty acids in the triglycerides.
The samples presented a wide range of fatty acids, most of which varied in content among species. The compositions of the
acids at the 3 positions also varied among species, reflecting the content of these acids in the triglycerides. However, there
was a general similarity in fatty acid positional distribution patterns for all the species with the exception of the echidna.
The echidna exhibited a completely different fatty acid positional distribution pattern. The saturated acids were preferentially
esterified at thesn-1-position whereas the unsaturated acids were selectively esterified at thesn-2-position. The triglyceride carbon number distribution of milk from the above species (with the exception of the Weddell
seal) was determined by gas liquid chromatography and compared to that predicted by the 1-random-2-random-3-random fatty acid
distribution hypothesis. Agreement was excellent between observed and predicted composition for echidna, koala, Tammar wallaby,
guinea pig and pig milk, and agreement was reasonable for dog, cat, horse and cow milk. Results are discussed in relation
to biochemical mechanisms. 相似文献
11.
Hiromi Yoshida Sako Kanei Yuka Tomiyama Yoshiyuki Mizushina 《European Journal of Lipid Science and Technology》2006,108(2):149-158
The fatty acid distribution of triacylglycerols (TAG) and major phospholipids (PL) within soybean seeds (Glycine max L.) was investigated in relation to their tocopherol contents. The lipids extracted from four cultivars were separated by thin‐layer chromatography into seven fractions. Tocopherols were predominantly detected in the axis, followed by cotyledons and seed coat. The major lipid components were TAG and PL, while hydrocarbons, steryl esters, free fatty acids and diacylglycerols (sn‐1,3 and sn‐1,2) were also present in minor proportions. With a few exceptions, the dominant PL components were phosphatidylcholine, followed by phosphatidylethanolamine or phosphatidylinositiol. Significant differences (p <0.05) in fatty acid distribution existed when different soybean cultivars were examined. However, the principal characteristics of the fatty acid distribution in the TAG were evident among four cultivars; unsaturated fatty acids were predominantly concentrated in the sn‐2 position, and saturated fatty acids primarily occupied the sn‐1 or sn‐3 position in the oils of the soybeans. 相似文献
12.
P. Nuhn 《European Journal of Lipid Science and Technology》1996,98(10):335-338
Analytics and biophysics of branched fatty acids in lipids . Objects of our investigations are long chain fatty acids with methyl groups in different positions and fatty acids with a different length of the sidegroup in α-position. The separation of racemic branched fatty acid methyl esters by gas chromatography on a chiral column depends on the structure of the branched fatty acid. Diastereomeric amides and phosphatidylcholines with α-branched fatty acid residues were separated preparatively. The branched fatty acids were incorporated into 1,2-diacyl-, 1-acyl-2-hexadecyl- and 2-acyl-1-hexadecyl-glycerophosphocholines and characterized by differential scanning calorimetry and X-ray diffraction. 相似文献
13.
Modification of the fatty acid composition of soy lecithin, principally at its 1-position, was investigated by interchange
reaction with the methyl ester of individual fatty acids and a lipase as the catalyst. The consequent effect on the surface
activity of soy lecithin was also examined. The interchange reaction was carried out by heating a mixture of soy lecithin
and methyl ester of a fatty acid at 60°C for 48 h with 10% (by weight of the reactants) Mucor miehei lipase. The lipase was filtered from the reaction mixture, and the product was isolated by combination of acetone extraction,
which removed the methyl ester fraction, and by preparative thin-layer chromatography separation. The soy lecithin showed
distinct change in its fatty acid composition in the sn-1 position. Capric acid was incorporated by 8.4%, while lauric acid and myristic acid were introduced at 14.1 and 15.7%,
respectively. The linolenic acid percentage was increased by about 10 units. The interfacial tension of soy lecithin changed
significantly after incorporation of various saturated fatty acids. 相似文献
14.
Edward N. Lambremont 《Lipids》1972,7(8):528-533
When14C-labeled acetate, fatty acids or fatty alcohols were injected into or fed to the tobacco budworm, acyl, alkyl and alk-1-enyl
moieties of the phospholipids incorporated radioactivity. Fatty acids were the principal precursor in acyl bond formation
and fatty alcohols in the synthesis of alkyl and alk-1-enyl glyceryl ethers. Detailed analysis of the etherlinked phosphoglycerides
revealed that most of the radioactivity was in the ethanolamine phosphoglycerides, and very little14C was found in the choline phosphoglycerides. In experiments of a short duration, the alkyl glyceryl ethers incorporated more
radioactivity than the alk-1-enyl glyceryl ethers. The reverse was found with long term experiments, when the alk-1-enyl ethers
had higher radioactivity. In addition to demonstrating the synthesis of ether-linked ethanolamine phosphoglycerides, the data
suggested that fatty alcohols and acids were interconverted by insects and that the alk-1-enyl ethers were derived from the
alkyl ethers.
Presented at the AOCS Meeting, Houston, May 1971.
The following abbreviations and terminology will be used: PE, PC, PI and PS for the generic terms ethanolamine, choline, inositol
and serine phosphoglycerides, respectfully. Alkyl glyceryl ether for 1-alkyl-2-acyl-sn-glycerol-3-phosphoryl-, and alk-1-enyl glyceryl ether for 1-alk-1′-enyl-2-acyl-sn-glycerol-3-phosphoryl-(commonly called plasmalogen). These are adapted from the tentative rules published inJ. Lipid Res. 8:522–528 (1967). 相似文献
15.
Samuel J. Friedberg 《Lipids》1976,11(8):587-593
Previous studies have shown that ingested fatty alcohols are absorbed as fatty acids and fatty acid esters, particularly triglycerides.
The present study was carried out to determine whether fatty alcohols are also transported as 0-alkyl glyceryl ethers, alk-1-enyl
glyceryl ethers, and as wax esters. Oxidation of fatty alcohols to other lipids was assessed by using a mixture of [1-3H] hexadecanol and [1-14C] hexadecanol of predetermined ratio. The results indicate that the absorption of fatty alcohol, and of its transport forms,
parallels the absorption of labeled fatty acids. Six to 25% of plasma radioactivity was present as 1-0-alkyl diacylglyceryl
ethers with a smaller proportion of ether lipids in the phospholipid fraction. In addition, 4–13% of the ingested hexadecanol
appeared in the plasma as a material having the chromatographic properties of wax ester. Fatty alcohols were not detected
in the plasma as alk-1-enyl lipids. 相似文献
16.
Diplodom patagonicus is a freshwater bivalve mollusk living in lakes of the patagonian Andes mountains in Argentina. Lipid composition and seasonal
changes in the mollusk were studied in the natural habitat. In addition to common nonpolar and polar lipids, small amounts
of alk-1-enyldiacylglycerol ethers and significant quantities of ceramide aminoethyl phosphonate were present. Total lipid
content changed during the year, primarily because of decreased triacylglycerols in winter. The fatty acid composition of
the lipids, remarkably different from that of marine bivalves, and even from other fresh water animals, was especially rich
in the ω6 fatty acids, linoleic and arachidonic (ca. 25%), and poor in the ω3 acids, 20∶5 and 22∶6. The ω6/ω3 acid ratio was
ca. 2, which is very high compared to marine bivalves. The fatty acid composition and the ω6/ω3 acid ratio were constant during
the whole year, suggesting a very stable diet, rich in vegetal detritus and poor in diatoms. The influence of environmental
temperature fluctuation with season on fatty acid composition also was negible. Modest proportions of 22∶2 nonmethylene-interrupted
(NMI) acids were detected and confirmed by mass spectrometry. It was shown that 20∶2 NMI acids were absent. 相似文献
17.
Whole soybeans were exposed to microwave roasting for 6, 12, and 20 min at a frequency of 2,450 MHz and were studied not only
for phospholipid composition but also for positional distribution of the fatty acids. During microwave roasting, the greatest
rate of phospholipid losses (P<0.05) was observed in phosphatidylethanolamine (PE), followed by phosphatidylcholine (PC) and phosphatidylinositol (PI),
respectively. Therefore, the effects of microwave roasting on the composition and positional distribution of the fatty acids
are likely clearer in PE than in PC or PI. However, the principal characteristics for the positional distribution of fatty
acids are still retained during microwave roasting: unsaturated fatty acids, especially linoleic, are predominantly concentrated
in the 2-position, and saturated fatty acids, especially palmitic, primarily occupy the 1-position after 12 or 20 min of roasting.
The results suggest that unsaturated fatty acids located in the 2-position are significantly protected from microwave roasting. 相似文献
18.
Soybeans of the Hawkeye variety were picked at eleven periods from 30 to 111 days after flowering and extracted with chloroform-methanol.
The triglyceride fraction of five pickings, selected 35 to 91 days after flowering (when synthesis of lipid was most active),
were isolated by silicic acid thin layer chromatography (TLC) and species composition determined using argentation TLC and
lipase hydrolysis. The triglyceride content of the total lipid increased from 6.5% at 30 days after flowering to 85% in the
mature bean (111 days). The major changes in fatty acid composition of the triglycerides occurred during the first 52 days
after flowering. During this period linolenic acid decreased from 34.2% to 11.7%, the percentages of linoleic and oleic acids
increased, stearic remained fairly constant and palmitic decreased slightly. Large quantitative changes occurred in the molecular
species of the triglycerides of the bean during maturation; some triglycerides containing linolenic acid could not be detected
approximately 66 days after flowering. Although changes occurred in the percentage and amount of each triglyceride species,
the positional distribution of fatty acids remained virtually unchanged throughout maturation. Linolenic acid was distributed
fairly uniformly between the β-position and the α-positions, linoleate favored esterification in the β-position, and oleate
the α-positions. Most of the stearic and palmitic acids were esterified in the α-positions. The consistency of the positional
arrangement of the fatty acids indicated that the mode of glyceride synthesis was established very early during maturation
and molecular species composition was controlled by the fatty acids available for synthesis. 相似文献
19.
C. Gail Stinson John M. deMan John P. Bowland 《Journal of the American Oil Chemists' Society》1967,44(4):253-255
Pigs were slaughtered at 16 weeks of age, and fat samples were obtained from outer and inner shoulder, outer and inner loin, and kidney. Fatty acid composition and glyceride type of distribution were determined. Glyceride structure was determined by pancreatic lipase hydrolysis. There were highly significant differences in fatty acid composition between sites. Fatty acids containing less than 18 carbon atoms were preferentially incorporated in the internal positions of the glycerides. The content of saturated fatty acids and fatty acids containing less than 18 carbon atoms at the 2-position of shoulder and loin glycerides was higher than in kidney glycerides. Differences in glyceride types were noted between sites. 相似文献
20.
W. E. Neff R. O. Adlof H. Konishi D. Weisleder 《Journal of the American Oil Chemists' Society》1993,70(5):449-455
The triacylglycerols ofVernonia galamensis andCrepis alpina seed oils were characterized because these oils have high concentrations of vernolic (cis-12,13-epoxy-cis-9-octadecenoic) and crepenynic (cis-9-octadecen-12-ynoic) acids, respectively. The triacylglycerols were separated from other components of crude oils by solid-phase
extraction, followed by resolution and quantitation of the individual triacylglycerols by reversed-phase high-performance
liquid chromatography with an acetonitrile/methylene chloride gradient and flame-ionization detection. Isolated triacylglycerols
were characterized by proton and carbon nuclear magnetic resonance and by capillary gas chromatography of their fatty acid
methyl esters. The locations of the fatty acids on the glycerol moieties in the oils were obtained by lipolysis. TheVernonia galamensis oil contained 50% trivernoloyl and 21% divernoloyllinoleoyl glycerols along with 20% triacylglycerols with one vernolic and
two other fatty acids. TheCrepis alpina oil contained 36% tricrepenynoyl and 33% dicrepenynoyllinoleoyl glycerols, 17% triacylglycerols with two crepenynic and one
other fatty acid and 7% triacylglycerols with one crepenynic acid and two other fatty acids. Vernolic acid was found at both
the 1(3)- and 2-glycerol carbons but was more abundant at the 1,(3)-position in theVernonia galamensis oil. Crepenynic acid was found at both glycerol carbon positions but was more abundant at the 2-position in theCrepis alpina oil.
Visiting scientist from Technical Research Institute, Snow Brand Milk Company, Ltd., Saitana, Japan. 相似文献