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1.
The lipid composition of pig liver has been determined. The principal glycerolipids, i.e., triglycerides, phosphatdyl choline,
phosphatidyl ethanolamine and phosphatidyl inositol, were isolated and the positional distribution of fatty acids in each
determined by stereospecific analysis procedures. Previous results for the triglycerides were confirmed, while the phospholipids
were similar in structure to those found in most other animal livers. The triglycerides were separated into simpler molecular
species by combinations of silver nitrate thin layer chromatography and high temperature gas liquid chromatography, but the
proportions found did not agree well with those calculated assuming a 1-random, 2-random, 3-random arrangement. The phospholipids
were hydrolyzed with phospholipase C and converted to diglyceride acetates that were fractionated into simpler molecular species
by the same procedures as were used with triglycerides. Highly specific fatty acid combinations were found in molecular species,
and these specificities were very similar to those reported in similar lipids from the livers of such disparate species as
the rat and chicken. 相似文献
2.
The lipid composition of beef and human pituitary was determined by chromatographic and spectrophotometric methods. Beef pituitary
lipid contained about 25% nonpolar lipids and 75% phospholipids whereas nonpolar lipids made up approximately 60% of the total
in human pituitaries. The main nonpolar (i.e., low polarity) lipids in human pituitary were triglycerides, cholesterol, free
fatty acids and an unidentified component in the triglyceride fraction. Cholesterol was the major nonpolar lipid component
in freshly collected beef anterior and posterior pituitary, but the amount of free fatty acids appeared to increase during
storage. Preliminary investigation of the unknown nonpolar lipid in human pituitaries suggested that it was an unsaturated
hydroxy compound with no carbonyl functions. Thin layer chromatography indicated that it was also present in smaller amounts
in freshly collected beef pituitaries. The main phospholipids of beef anterior, posterior and human pituitary were phosphatidyl
ethanolamine, phosphatidyl choline, phosphatidyl inositol, phosphatidyl serine and sphingomyelin. The fatty acid composition
of total nonpolar lipids, free fatty acids, total phospholipids, phosphatidyl ethanolamine and phosphatidyl choline of beef
anterior and posterior pituitary was determined by gas liquid chromatography. Mixtures of saturated and unsaturated fatty
acids ranging from C12 to C22 were present; the main fatty acids were palmitic, stearic, oleic, linoleic and arachidonic. 相似文献
3.
Two dimensional thin layer chromatographic separation of polar lipids and determination of phospholipids by phosphorus analysis of spots 总被引:35,自引:0,他引:35
Separation of polar lipids by two-dimensional thin layer chromatography providing resolution of all the lipid classes commonly
encountered in animal cells and a sensitive, rapid, reproducible procedure for determination of phospholipids by phosphorus
analysis of spots are described. Values obtained for brain and mitochondrial inner membrane phospholipids are presented. 相似文献
4.
The effect of temperature on the lipid composition ofCephalosporium falciforme andCephalosporium kiliense, causative agents of maduromycosis, was investigated. The fungi were grown at 28.5 C and 37 C in a chemically defined medium.
The lipids were solvent extracted, purified on Sephadex, and separated into their component classes by silicic acid column
chromatography. Five lipid classes were found: (a) sterol esters, (b) triacylglycerides, (c) free fatty acids, (d) sterols,
and (e) phospholipids. Fatty acids were analyzed by gas liquid chromatography and phospholipids by thin layer chromatography.
Temperature induced changes of varying degrees occurred in both the fatty acid phospholipid fractions of each organism. 相似文献
5.
The fat globules of milk are surrounded by a membrane, which contains a triple layer of phospholipids. Concentrated cream is thus a very good raw material for further processing in order to make a powder, enriched in phospholipids. A powder can in this way easily be produced with 20% phospholipids using only common dairy processes such as centrifugation and membrane filtration. Milk phospholipids differ in compositions from existing commercial sources such as soybean lecithins and egg lecithins particularly with respect to the content of two bioactive phospholipids namely sphingomyelin (about 24%) and phosphatidylserine (12%). Sphingomyelin is an active agent controlling the intestinal uptake of cholesterol and triacylglycerols in human nutrition. Intake of phosphatidyl serine has clinically documented effects in maintaining cognitive performance like memory and stress control. A milk phospholpids enriched product thus offers a 100% natural alternative to the well‐established, semi‐synthetic head‐group exchanged phosphatidyl serine from soy lecithin now existing on the market for functional foods formulations. 相似文献
6.
The total lipids were extracted from the livers of newborn lambs, from the livers of lambs during the first week after birth
and from the livers of adult sheep. After separation from the nonphospholipids on columns of silicic acid the phospholipids
were analyzed by thin layer chromatography and quantitative gas liquid chromatography. In all samples phosphatidyl choline
and phosphatidyl ethanolamine together accounted for about 80% of the total liver phospholipids. The phosphatidyl choline-phosphatidyl
ethanolamine ratio in the livers of the newborn lambs was markedly less than the ratio in the livers of the adult sheep. Moreover
there was a pronounced increase in the phosphatidyl cholinephosphatidyl ethanolamine ratio in the livers of the lambs during
the first week after birth. In the liver phospholipids of the lambs the concentration of phosphatidyl inositol was lower and
the concentrations of phosphatidyl serine and sphingomyelin were greater than the corresponding concentrations in the liver
phospholipids of the adult sheep. It is proposed that the change in the phosphatidyl choline-phosphatidyl ethanolamine ratio
in the livers of the lambs during the first week after birth is due, at least in part, to the marked change that occurs in
the linoleic acid-arachidonic acid ratio in the tissues of the lamb during this period. 相似文献
7.
The lipid components of four strains ofAgricus bisporus (Lange) Sing., the cultivated mushroom, were analyzed. Both sporophore and mycelial samples were obtained from beds in normal
production. A method for obtaining mycelium free of compost was developed. Neutral lipids were separated from polar lipids
by silicic acid column chromatography. Each fraction was separated by thin layer chromatography. Fatty acid methyl esters
were analyzed by gas liquid chromatography and mass spectrometry. Sporophore extracts contained free sterol, free fatty acid,
triglycerides, phosphatidyl choline and phosphatidyl ethanolamine. High amounts of linoleic acid were found in both neutral
and polar lipid fractions. Mycelial extracts contained free fatty acids, triglycerides, phosphatidylcholine and phosphatidyl
ethanolamine. No free sterol could be detected. Linoleic acid was also present in large amounts.
Paper 3798 in the Journal Series of The Pennsylvania Agricultural Experiment Station. 相似文献
8.
A method is described for the direct quantitative analysis of the lipid classes of mammalian tissue lipids using high performance
liquid chromatography (HPLC) with a flame ionization detector (FID). The lipid is extracted from the tissue with chloroform/methanol
after deactivation of hydrolytic enzymes and removal of nonlipid substances by extraction with hot dilute acetic acid (0.05N).
Separation of the lipid classes is performed with a column (45 cm × 0.2 cm id) of 8 μm silica (Spherisorb, Phase Sep, Hauppague,
NY) treated with concentrated ammonium hydroxide at a solvent flow rate of 0.5 ml/min, which requires a pressure of ca. 900
psi. Cholesteryl esters (CE) and triglycerides (TG) are eluted first with Skellysolve B/methylene chloride (1∶1, v/v); cholesterol
(CH) is eluted with chloroform/methylene chloride (1∶2, v/v) and the phospholipids with methanol containing 6% ammonium hydroxide
added to the latter solvent in a linear gradient. The neutral lipids are eluted in ca. 12 min and the phospholipids in an
additional 30 min. The relative amount of each lipid class was determined from standard curves of the peak areas obtained
according to response factors using erucyl alcohol as an internal standard. The method was applied to samples of kidney, liver
and serum of rats. Duplicate analyses were generally within ca. 1.0% and good agreement was obtained in the analysis of the
lipid classes of Azolectin and liver mitochondria lipid compared to thin layer chromatography (TLC) via photodensitometry
of charred spots or phosphorus analysis of recovered phospholipids. 相似文献
9.
E. J. Weber 《Journal of the American Oil Chemists' Society》1981,58(10):898-901
The lipid and fatty acid compositions of commercial corn and soybean lecithins were compared. The types of lipids were similar,
but the proportions varied. The ratio of glycolipids to phospholipids was 0.36 for corn lecithin and 0.14 for soybean. Phosphatidylcholine
and phosphatidylinositol were major phospholipids in both lecithins. In soybean lecithin, the percentage of phosphatidyleth-anolamine
equaled that of phosphatidylinositol, but in corn, the percentage of phosphatidylethanolamine was only about one-fourth the
percentage of phosphatidylinositol. High levels of phosphatidic acid in both the corn and soybean preparations indicated some
degradation of the phospholipids during processing. The major differences in fatty acid compositions were a higher percentage
of oleic acid and lower percentages of stearic and linolenic acids in corn compared to soybean. The lower level of linolenic
acid should give corn lecithin greater resistance toward autoxidation and the development of off-flavors. 相似文献
10.
The lipid of immature soybeans was extracted with chloroform-methanol and fractions containing the glycolipids and phospholipids
were separated by column chromatography. Phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), phosphatidyl inositol
(PI), phosphatidic acid (PA) phosphatidyl glycerol (PG), n-acyl phosphatidyl ethanolamine (APE) and sulfolipid (SL) were identified
by thin layer chromatography (TLC). Sterol glucoside (SG), esterified sterol glucoside (ESG), digalactosyl diglyceride (DGDG)
and cerebrosides (CE) were isolated by TLC and identified by color reactions, chemical degradation and spectral analysis. 相似文献
11.
George Rouser Gene Kritchevsky Dorothy Heller Ellen Lieber 《Journal of the American Oil Chemists' Society》1963,40(9):425-454
Two new schemes for fractionation of complex lipid mixtures are presented. Their use for the study of lipids of beef brain,
beef liver, and the sea anemone are described. Apparatus and techniques for working in an inert atmosphere, evaporation of
solutions in the cold under nitrogen, use of infrared spectroscopy for examination of lipids and their hydrolysis products,
preparation and clution of diethylaminoethyl (DEAE) cellulose and silicic acid-silicate columns and general column combinations
that can be used to fractionate complex lipid mixtures are considered in detail. The first scheme, employing DEAE cellulose
columns followed by thin layer and paper chromatographic examination of the fractions, was applied to liver lipids. The many
components, some of them new lipids not previously detected, are clearly seen with this technique but are not seen when paper
or thin layer chromatography alone or silicic acid chromatography are used.
The second scheme employing DEAE for initial fractionation, followed by complete separation on silicic acid and silicic acid-silicate
columns, was applied to lipids of the sea anemone and beef brain. Typical lecithin and phosphatidyl ethanolamine were isolated,
but sphingomyelin was not found. A new sphingolipid, ceramide aminoethylphosphonate, with a free amino group and a direct
carbon to phosphorus bond was isolated and characterized. The methods used for quantitative isolation, the infrared spectra,
and the amounts of cholesterol, ceramide, cerebroside, galactosylglyceride, sulfatide, sphingomyelin, lecithin, phosphatidyl
ethanolamine, phosphatidyl serine, phosphatidyl inositol, triphosphoinositide, phosphatidic acid, cardiolipin, and ganglioside
of beef brain are presented. Finally, the types of lipid-nonlipid interactions disclosed by column chromatography and their
potential application to biological problems are discussed. 相似文献
12.
Freshly collectedCalanus pacificus were maintained in sea water containing 25 μCi/ml [32P]orthophosphate or 1 μCi/ml [14C]acetate at 10 C for 24 hr. The animals took up label from the environment and incorporated it into various lipid fractions.
After incubation with [14C]acetate the order of specific activity of the different lipid classes was: phospholipids > free fatty acids > wax esters
> triglycerides. Argentation thin layer chromatography of the fatty acid methyl esters showed that ca. 50% of the activity
was in saturated fatty acids and 34% in polyunsaturated acids. When the animals were exposed to [32P]orthophosphate, lysophosphatidyl choline became most heavily labeled, followed by lysophosphatidyl ethanolamine, sphingomyelin,
phosphatidyl ethanolamine, and phosphatidyl choline. Comparison of the data obtained with those available for decapods and
mammals revealed striking similarities between these phylogenetically distant groups. It is believed that labeling the lipids
of marine and freshwater planktonic crustaceans in this way will provide much information about the metabolism of lipids in
these organisms. 相似文献
13.
Peter Kaufmann Urban Olsson Bengt G. Herslof 《Journal of the American Oil Chemists' Society》1990,67(8):537-540
Lecithins are widely used as multipurpose additives in the pharmaceutical and food industries. This implies the need for an
analytical means for the assessment of process performance prior to full-scale processing. A general methodology was developed
for the classification of lecithins with respect to this property. The strategy developed utilizes pattern recognition methods,
fatty acid composition of the phospholipid classes(phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol) and
lipid class analysis by high performance liquid chromatography to identify the lecithins with acceptable performance, e.g.,
emulsifying behavior. 相似文献
14.
Total lipids from whole pig adrenal glands as well as from their mitochondria, microsomes, liposomes, and cell sap were extracted and fractionated first into neutral lipids and phospholipids. The highest percentage of neutral lipids was found in the cell sap, and the lowest in the microsomal fraction. Neutral lipids were subfractionated into cholesteryl esters, free cholesterol, triglycerides, and free fatty acids. Cholesteryl esters were distributed throughout the liposomes. Free fatty acids represented a substantial part of cell sap lipids, but were present also in the mitochondria, microsomes, and liposomes. Fatty acids of all fractions were analyzed by gas liquid chromatography. Free fatty acids and cholesteryl ester fatty acids from all cellular fractions were similar in composition and were characterized by considerable quantities of linoleic and arachidonic acid. Triglycerides were characterized by an increased percentage of palmitic and a low content of arachidonic acid. Phosphatidyl choline, phosphatidyl ethanolamine, diphosphatidyl glycerol, and sphingomyelin plus phosphatidyl inositol were isolated from the lipids by preparative thin layer chromatography, and their fatty acids analyzed by gas liquid chromatography. Phosphatidyl choline and phosphatidyl ethanolamine from mitochondria, microsomes, and cell sap were very similar in respect of their fatty acid composition. Sphingomyelin plus phosphatidyl inositol was characterized by a high content of C22:2omega6. Diphosphatidyl glycerol was present in mitochondria and in the cell sap. 相似文献
15.
16.
In an effort to produce structurally divergent lecithins for testing of their functional properties and use in food products, several tools have been developed to carry out modifications in the polar head group distribution of the native phospholipids in soybean lecithin. These tools include physical, chemical and enzymatic techniques. Using a combination of acetone de‐oiling, ethanol fractionation, N‐acetylation and enzymatic hydrolysis and transphosphatidylation with a phospholipase D from Streptomyces sp., a set of lecithins with modified head group distributions were produced. The kinetics of the enzymatic head group hydrolysis and transphosphatidylation was studied in detail. Reaction rates and selectivity (transphosphatidylation / hydrolysis) were affected by both lecithin concentration and donor alcohol concentration. Hydrolysis, forming phosphatidic acid, was strongly dependent on both concentrations, whilst transphosphatidylation, forming phosphatidyl glycerol (or phosphatidyl ethanolamine or phosphatidyl serine), was only influenced by the donor alcohol. This resulted in a reduction in selectivity at high initial lecithin concentrations and suggested the use of a reactant feeding strategy. Enrichment of the phosphatidyl choline content of native soybean lecithin was achieved by ethanol fractionation and phosphatidyl inositol enrichment was by N‐acetylation with acetic anhydride followed by de‐oiling. The application of these tools, together with others designed to modify the fatty acid composition of phospholipids, was used to produce 10‐100 g quantities of divergent lecithins and can be routinely used at lab‐scale. 相似文献
17.
Phosphatidyl ethanolamine was isolated from total egg yolk lipids by preparative thin layer chromatography (TLC). The purified
phosphatide contained 3% of the alkoxy derivative. It was degraded to diglycerides in the presence of purified sphingomyelin
by phospholipase C fromClostridium welchii. The diglycerides were acetylated and resolved on the basis of unsaturation by argentation TLC. The fatty acid composition
of the original phosphatidyl ethanolamine and the derived acetates was determined by gas chromatography, as was the molecular
weight distribution of the diglyceride acetates. The placement of the fatty acids in the parent phosphatide was deduced by
hydrolysis with phospholipase A fromCrotalus atrox, and in the acetates with pancreatic lipase. Some 33 major species of phosphatidyl ethanolamine were identified and compared
to those for egg yolk lecithins.
Presented in part at the Canadian Federation of Biological Societies Meeting, Kingston, June 1968. 相似文献
18.
The brain is a lipid-rich organ containing complex polar lipids including phospholipids (PLs) and sphingolipids. These lipids
are involved in the structure and function of cell membranes in the brain. We developed a fast and efficient liquid chromatography–tandem
mass spectrometry (LC–MS/MS) method to quantify five different classes of PLs [Choline glycerophospholipid (consists of phosphatidyl
choline and plasmenyl choline in these samples), ethanolamine glycerophospholipid (consist of phosphatidyl ethanolamine and
plasmenyl ethanolamine in these samples), phosphatidyl serine, phosphatidyl inositol, and sphingomyelin] in the brain tissues
of 80-day-old Wistar rats. The PLs were extracted from rat brain using chloroform/methanol/water. After separation using a
hydrophilic high performance liquid chromatography column, PL-class-specific fragmentation (head group identification) with
a tandem mass spectrometer in positive ion mode was utilized to measure changes in the relative concentration of the five
PL classes. The advantage of this approach was its improved specificity over previously reported LC–MS methods. The method
had good repeatability (coefficient of variation 3–9%, excluding phosphatidyl inositol) and recovery (92–103%) and compared
well with more laborious traditional methods. 相似文献
19.
Studies are reported on the composition of the lipids of human liver and hepatoma tissues from male adults. Liver tissues
were obtained from individuals who died from causes other than liver disease or cancer. The hepatoma tissues were obtained
from individuals shortly after they succumbed to cancer. The total lipid of each tissue was fractionated quantitatively by
silicic acid column chromatography into neutral lipid, glycolipid, and phospholipid fractions. These fractions were analyzed
by thin layer chromatography and converted to methyl esters for analysis of their constituent fatty acids by gas liquid chromatography.
In comparison to liver tissue, the total amount of lipid in the hepatoma tissues was generally higher and more variable; the
lipid of one hepatoma was ca. 92% of the dry wt of the tissue. The greater lipid content of the hepatoma tissues was due to
the high percentage of neutral lipid. Except for one specimen, there was ca. the same amount of glycolipid in the hepatoma
as in the liver tissues, but the composition of the glycolipid fraction of the hepatoma lipid differed considerably, particularly
in the ganglioside fraction. The phospholipid fraction of hepatoma lipid was much lower than that of liver but exhibited only
quantitative differences in composition. No glyceryl ether diesters and only traces of plasmalogens of phosphatidyl choline
or phosphatidyl ethanolamine were detected in the liver and hepatoma lipids. The levels of monoenoic acids were higher and
those of linoleic and polyunsaturated fatty acids lower in the hepatoma lipids. Positional isomers of trienoic acids not normally
present in liver tissue were detected in hepatoma lipids. The abnormalities observed in lipid composition indicated interferences
in the regulatory processes of lipid metabolism in human hepatoma similar to those observed in animals. 相似文献
20.
The contents of phosphatidyl N-methyl-and N,N-dimethylaminoethanol were determined in the liver of rats injected with (Me-C14) methionine. Total phospholipids were extracted from aliquots of the liver and fractionated by two-dimensional thin layer
chromatography after addition of carrier phosphatidyl-N-methyl-and N,N-dimethylaminoethanol. The radioactivity present in
the two phosphatide spots was determined and used to calculated total disintegrations per min/100 g body wt. The remainder
of the livers was pooled, and total phospholipids were isolated and subjected to acid hydrolysis. N-methyl- and N,N-dimethylaminoethanol
were purified by thin layer chromatography, and their specific activity was determined after quantitation by gas liquid chromatography
and radioactivity measurement. The liver contents of phosphatidyl N-methyl- and N,N-dimethylaminoethanol were determined by
dividing disintegrations per min/100 g body wt by the specific activity of N-methyl- or N,N-dimethylaminoethanol. 相似文献