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1.
Lipid metabolism of brain tissue in culture 总被引:2,自引:0,他引:2
John H. Menkes 《Lipids》1972,7(2):135-141
Tissue explants from frontal lobes of rat brain were used for the study of cerebral fatty acid metabolism. After tissues had
been maintained in serum-supplemented medium, a lipid free medium was substituted and metabolic studies were carried out.
Under these conditions explants continued to take up lipid precursors for at least 48 hr. Stearic acid 1-C14, palmitic acid 1-C14 and lignoceric acid 1-C14 were bound to cells as the free fatty acids or incorporafed into neutral lipids (particularly triglycerides), glycolipids
and phospholipids. In the galactolipid fraction, cerebrosides were the principal radioactive lipids. Choline phosphoglycerides,
ethanolamine phosphoglycerides, inositol phosphoglycerides and serine phosphoglycerides were the principal radioactive phospholipids.
Fatty acids were incorporated into cellular lipids either unchanged or after desaturation, chain elongation, or both. In a
patient with a demyelinating disease, precursor uptake was reduced and chain elongation and desaturation of the fatty acid
was diminished. In a patient with generalized GM2 gangliosidosis, glycolipids other than cerebrosides were labeled to a greater extent than normal. These studies exemplify
the usefulness of tissue explants for prolonged metabolic studies in normal and pathological specimens of brain.
One of 13 papers presented at the symposium “Lipid Metabolism in Cells in Culture,” AOCS Meeting, Houston, May, 1971. 相似文献
2.
The fatty acid composition of triglyceride and total phospholipid fractions of adultSchistosoma mansoni has been examined. Both triglyceride and phospholipid contained fatty acids varying in chain length from 12 through 24 carbons;
trace amounts of shorter chain components were found in the triglyceride fraction. A docosahexaenoic acid in the triglyceride
fraction represented the highest degree of unsaturation encountered. Branched chain fatty acids of 16 and 18 carbons were
found in both phospholipid and triglyceride. Examination of fatty acids from fluke total lipid revealed the presence of small
amounts of odd numbered carbon fatty acids varying in chain length from 13 through 23 carbons. 相似文献
3.
Phospholipids of 27 species of insects representing 6 orders and 20 families were examined by DEAE cellulose column chromatography
to determine the choline/ethanolamine phosphoglyceride ratios, and by gas chromatography to determine the constituent fatty
acids.
The phosphorus in the ethanolamine phosphoglycerides accounted for approximately 50% of the total lipid phosphorus in aphids
(Homoptera) and in all but one family of Diptera (flies) examined while the phosphorus in the choline phosphoglycerides accounted
for only about 25%. Ethanolamine and choline phosphoglycerides were present in approximately equal proportions in one family
of Diptera and in the Coleoptera (beetles) examined. In the other insects examined choline phosphoglycerides predominated,
ethanolamine phosphoglycerides comprising only about 25–30% of total lipid phosphorus as they do in most mammalian tissues.
Diptera in which ethanolamine phosphoglycerides were the major phosphatides were also characterized by high proportions of
fatty acids less than 18 carbons long, particularly palmitoleic acid, in the neutral lipids. Aphids are characterized by a
preponderance of 14-carbon fatty acids. The evidence suggests that predominance of ethanolamine phosphoglycerides is associated
with a preponderance of shorter chain fatty acids in the neutral lipids.
Differences also exist between Diptera and other insects in the fatty acid compositions of different phosphatides, particularly
with respect to the distribution of 18-carbon acids. The compositions observed in insects that contained large amounts of
the choline phosphoglycerides are similar to those found in vertebrates. Similarities in fatty acid composition of the choline
phosphoglycerides in such widely divergent organisms suggest that the fatty acids may play a greater role in phospholipid
function than has heretofore been demonstrated.
Contribution Number I.P.R.I. 74. 相似文献
4.
The lipid content, distribution and fatty acid composition of highly purified bovine liver nuclear membranes was determined
and compared to those of microsomes prepared in parallel. Contrasted with microsomes, nuclear membranes while containing nearly
the same levels of lipid had more cholesterol and total neutral lipid and less phospholipid. Phospholipid and neutral lipid
patterns generally were similar for the two types of membranes. The same fatty acids, in similar proportions, were observed
in respective total lipid, total polar lipid, phosphatidyl choline and phosphatidyl ethanolamine fractions of the two membrane
types. The microsomal lipid fractions contained slightly greater percentages of unsaturated fatty acids. With respect to previous
results from preparations contaminated with nonmenbranous nuclear material, purified fractions contained more total lipid
on a protein basis and more total unsaturated fatty acids. Only minor differences in levels and distribution of phospholipids
and neutral lipids were observed between the crude and highly purified fractions.
Purdue University AES Journal Paper No. 4482. 相似文献
5.
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
6.
1-14C-Acetic, 1-14C-palmitic, or 1-14C-stearic acid was incubated with minimal deviation hepatoma 7288C cells grown in culture to assess: de novo fatty acid synthesis, oxidation, desaturation, and elongation of saturated fatty acids, as well as the ability of media fatty acids to serve as precursors of cellular glycerolipids. Distribution of radioactivity in the individual lipid classes and the various fatty acids of triglyceride, phosphatidyl choline, and phosphatidyl ethanolamine was determined. The radioactivity among the monoenoic acid isomers derived from triglyceride, phosphatidyl choline, and phosphatidyl ethanolamine was analyzed by reductive ozonolysis. Only small amounts of the labeled substrates were oxidized to carbon dioxide. Except for labeled stearic acid, which also was incorporated heavily into phosphatidyl inositol and phosphatidyl serine, most radioactivity was recovered in triglyceride, phosphatidyl choline, and phosphatidyl ethanolamine. Synthesis of cholesterol and long chain fatty acids from labeled acetic acid demonstrated that these cells can perform de novo synthesis of fatty acids and cholesterol. Both labeled palmitic and stearic acids were desaturated to the corresponding delta9 monoenes, and palmitic and palmitoleic acids were elongated. The nexadecenoic acid fraction isolated from triglyceride, phosphatidyl choline, and phosphatidyl ethanolamine, when acetic or palmitic acid was the labeled substrate, showed that greater than 70 percent of the labeled acids were the delta9 isomer. Radioactivity of the octadecenoic acid fraction derived from labeled acetic or palmitic acids was nearly equally divided between the delta9 isomer, oleic acid, and the delta11 isomer, vaccenic acid. Desaturation of labeled stearic acid produced only oleic acid. These data demonstrate that the biosynthesis of vaccenic acid in these cultured neoplastic cells proceeds via the elongation of palmitoleic acid. The relatively high level of vaccenic acid synthesis in these cells suggests that the reported elevation of "oleic acid" in many neoplasms may result from increased concentration of vaccenic acid. 相似文献
7.
The lipid composition of Yoshida ascites hepatoma cells was analyzed together with that of ascitic plasma and of livers and
blood plasma from host and normal rats. In comparison to normal livers, host livers showed no significant differences in the
content of the various lipid classes, but contained a higher percentage of palmitic acid and a lower proportion of arachidonic
acid in the major phospholipid classes. In addition, tumor growth induced a marked hypertriglyceridemia in host animals; changes
in the concentration of other plasma lipid classes were not statistically significant. The ascitic plasma contained small
amounts of lipids mainly constituted by cholesteryl esters and phospholipids. Yoshida hepatoma cells contained less phospholipids
in comparison to both host and normal liver, while the increased level of triglycerides and the decrease of free fatty acids
were not statistically significant. Hepatoma cells showed appreciable amounts of ether-linked lipids associated in part to
neutral lipids (as glyceryl ether diesters) and, in part, to ethanolamine and choline phosphoglycerides. The alkyl groups
in GEDE as well as in ethanolamine and choline phosphoglycerides were mainly constituted by C16∶0 and C18∶0 followed by C18∶1. The alk-1-enyl groups in ethanolamine and choline phosphoglycerides were C16∶0 and C18∶0 with only a minor proportion of C18∶1. In comparison to both host and normal liver, Yoshida hepatoma cells showed significant changes in the fatty acid composition
of neutral lipids and phospholipids. Some of the major changes consisted of an increase of monoenoic acids associated with
a decrease of arachidonic and docosahexaenoic acids in phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol. 相似文献
8.
Protein, total phospholipid, phosphatidyl cholines and phosphatidyl choline fractions from liver mitochondria and microsomes
of female rats were analyzed after treatment with CCl4 (0.3 ml of CCl4 suspended in corn oil) or ethionine (50 mg in 0.9% saline) or after feeding a choline deficient, low protein diet for seven
days. Phosphatidyl cholines were separated into four fractions differing in the degree of fatty acid unsaturation. Over 50%
of total phosphatidyl choline phosphorus was present in fraction 3 of liver mitochondria and microsomes. The major fatty acid
in fraction 1 was docosahexaenoic acid. Fraction 4 contains oleic and linoleic acids. Arachidonic acid occurs in fraction
2 and 3. Ethionine decreased the amount of microsomal protein and phosphatidyl choline fraction 1 of mitochondria. Microsomal
protein was decreased by CCl4. The choline deficient, low protein diet caused a decrease in mitochondrial and microsomal phospholipids. The amount of the
mitochondrial phosphatidyl choline decreased. Corn oil increased the level of phosphatidyl choline fraction 3. Choline deficiency
decreased the amount of phosphatidyl choline fraction 3, increased fraction 4 of mitochondria and microsomes and increased
fraction 1 of microsomes. 相似文献
9.
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
10.
L1210 leukemia cells can utilize all of the main fatty acids that normally are present in the ascites fluid in which they
grow. This finding is consistent with the view that L1210 cells derive most of their fatty acids from the ascites fluid. From
80–90% of each fatty acid was incorporated into cell lipids without structural modification, suggesting that the lipid composition
of these cells can be altered by changing the type of fatty acids to which they are exposed. Most importantly, the palmitate
that was subsequently incorporated into total cell phospholipids was elongated and desaturated somewhat more than that incorporated
into triglycerides. This difference was due primarily to more extensive modification of the palmitate incorporated into the
ethanolamine phosphoglycerides fraction. Although there was no difference between total phospholipids and triglycerides with
linoleate, more of the linoleate incorporated into ethanolamine phosphoglycerides was elongated and further desaturated than
that incorporated into choline phosphoglycerides and triglycerides. These findings indicate that fatty acids incorporated
into various cell lipid fractions are not structurally modified to the same extent. There appears to be greater modification
of fatty acid used for ethanolamine phosphoglyceride synthesis as compared with triglyceride and choline phosphoglyceride
synthesis. 相似文献
11.
P. K. J. P. D. Wanasundara U. N. Wanasundara F. Shahidi 《Journal of the American Oil Chemists' Society》1999,76(1):41-48
Flax (Linum usitatissimum L.) seeds were germinated for 8 d under laboratory conditions, and changes in their lipid fraction were studied by various
chemical and chromatographic methods. Total lipid content of the seeds was reduced fourfold at the end of the 8-d germination
period as compared to ungerminated seeds on a fresh weight basis. The neutral lipids comprised the major fraction of seed
lipids, and triacylglycerols predominated over all other lipid components even during the germination period. Both the spectrophotometric
and thin-layer chromatography-flame-ionization detection methods of quantification showed a considerable increase in the content
of free fatty acids. The glycolipid fraction of lipids increased, but the phospholipid fraction exhibited only minor changes.
Lipase activity of flaxseed increased at the beginning of germination and then remained constant until the fifth day. Phosphatidylcholine
was the major phospholipid of flaxseed lipids, and its content was reduced during the germination. The contents of lysophosphatidylcholine
and phosphatidic acid increased from negligible amounts to 46% of the total phospholipids. Linolenic, linoleic, and oleic
acids, respectively, were the predominant fatty acids of all the lipid fractions of flaxseed, and remained unchanged during
the germination period. The glycolipid fraction had the lowest content of polyunsaturated fatty acids. Fatty acids C14:0, C20:0, C24:0, C20:1, C22:1, and C20:5 appeared after d 2 of germination in neutral, glyco- and phospholipid fractions. 相似文献
12.
Comparative study of the molecular species of chloropropanediol diesters and triacylglycerols in milk fat 总被引:1,自引:0,他引:1
In an effort to establish the origin of the fatty acid esters of 3-chloropropanediol, which recently have been isolated in
small amounts from goat milk, we compared the molecular species composition of the chlorohydrin diesters and of goat milk
triacylglycerols. The chloropropanediol diesters were found to be composed of molecular species containing C10−C18 fatty acids and corresponded closely in carbon number to those calculated for the long chain sn-1,2-diacyl-glycerol moieties
of goat milk triacylglycerols. The molecular species of goat milk total triacylglycerols contained C4−C18 fatty acids. It is suggested that triacylglycerols and chloropropanediol diesters are derived from the same pool of long
chain fatty acids. A molecular distillate of bovine milk fat did not contain chloropropanediol diesters, while the available
samples of human milk fat were shown to contain alkyldiacylglycerols as the major components of a neutral lipid fraction corresponding
in polarity to the chloropropanediol diesters. 相似文献
13.
Using improved methods for fatty acid analysis and a density gradient method for separation of red cells according to age,
we analyzed the fatty acid composition of a young fraction and an old fraction of red cells from each of seven normal subjects
and from one patient with polycythemia vera. Twenty-four fatty acid peaks were quantified. The individual phospholipid composition
of both fractions was determined in the red cells of two normal sujects. Statistically significant changes in the relative
amounts of major fatty acids were observed with red cell aging. Furthermore, a pattern of change was evident in that the relative
amounts of four of the five fatty acids of C18 or shorter chain length showed an increase and all 19 fatty acids of C20 or longer chain length showed a decrease with red cell aging. While the change with aging in every fatty acid peak was not
statistically significant, the consistency in the direction of the change in the fatty acids of C20 or longer chain length was highly significant. A suggested change in the distribution of the major phospholipid groups with
red cell aging did not appear to explain completely the changes in fatty acids.
This work was done during the tenure of an Advanced Research Fellowship of the American Heart Association. 相似文献
14.
Cuphea seeds contain large amounts of medium chain (C8 to C14) fatty acids, mainly as triacylglycerols. The biosynthesis of these lipids was studied in vivo by incubating developingCuphea lutea seeds with labeled acetate. Incorporation of label into triacylglycerols and into medium chain fatty acids occurred principally
during the period of endogenous lipid deposition, but some label was encountered in these products even during seed dehydration.
At this later stage palmitate and oleate were the dominant labeled fatty acids. During the period of rapid endogenous lipid
deposition acyl lipids other than triacylglycerols were minor labeled components. The labeling patterns were consistent with
the Kennedy pathway for triacylglycerol biosynthesis. The fatty acid composition of the acyl-CoA pool was similar to the total
lipid fatty acid composition, but the acyl-ACP pool contained relatively more short chain acyl groups. Squalene was labeled
from acetate throughout the period of seed development, but labeled sterols were not detected. Using [2-14C]mevalonic acid lactone as substrate, squalene was the principal labeled product. Small amounts of label were found in free
sterols. However, in terms of mass, free sterol dominated over squalene. The possibility of two independent sites of isoprenoid
biosynthesis in the developing embryo is discussed. 相似文献
15.
Skin surface lipids of the dog 总被引:1,自引:0,他引:1
The skin surface lipid of the dog has been reported to contain a high proportion of diol diesters having a lower mobility
on thin layer chromatography than diesters from other species in spite of containing similar fatty acid and diol components.
In the present study, dog skin surface lipid was separated by preparative thin layer chromatography into sterol esters (42%),
wax diesters (32%), free sterols (9%), polar lipids (7%), and unidentified components (10%). The diesters contained 1,2-diols,
each esterified with one long chain fatty acid and one isovaleric acid moiety. The diols were principally branched chain C21 and C22 compounds while the long chain fatty acids esterified with them were mainly C20 and C21 branched compounds. The fatty acids from the sterol esters were mostly saturated, branched chain C19 to C23, together with 7% of straight chain monoenoic acids, principally C21 and C22. There were only trace amounts of free sterols other than cholesterol, while the esterified sterols contained 96% cholesterol
and 4% lathosterol. 相似文献
16.
The detailed composition of cellular lipid of more than 23 species of yeast has been determined quantitatively by thinchrography
on quartz rods, a method previously used for estimating cellular lipids of seven species of yeast. That data was fortified
by neutral and phospholipid quantitations on 30 species of yeast cells. Most of the test organisms contained 7–15% total lipid
and 3–6% total phospholipid per dry cell weight, except for the extremely high accumulation of triglycerides in two species
ofLipomyces. Qualitatively, 30 species of yeast cells contained similar neutral lipid constituents (triglyceride, sterol ester, free
fatty acid, and free sterol) and polar lipid components (phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine,
phosphatidyl inositol, cardiolipin, and ceramide monohexoside) without minor constituents. Based on the quantitative composition
of neutral lipids, the 30 species of yeast were divided into two groups, the triglyceride predominant group and the sterol
derivative group. These groupings were fairly well overlapped from the standpoint of the distribution characteristics of fatty
acid. The relative polar lipid compositions also grossly resembled each other. Only one exception of polar lipid composition
in yeast cells was found inRhodotorula rubra species which contained phosphatidyl ethanolamine as the most abundant phospholipid. Fatty acid distribution patterns in
yeast cells consistently coincided with other reports concerning fatty acid composition of yeast cells. Correlation of lipid
composition and classification of yeasts are suggested and discussed.
A part of this investigation has been reported at the 14th conference of the Japan Oil Chemists' Society, Nagoya, Japan, October
1975. 相似文献
17.
Fatty acid composition of neutral and polar lipid fractions from rat hearts was determined in rats of different ages as their
diet source changed. Piebald rats were weaned at 21 days and were fed standard lab chow. Lipids from rat hearts, mothers milk
and lab chow were purified on a Sephadex G-25 fine column and separated into neutral and polar lipid fractions by silicic
acid column chromatography. These lipid fractions were then hydrolyzed and methylated with BF3 in methanol, prior to gas liquid chromatographic separation on a 1/8 in. × 10 ft aluminum column of 15% EGS on 80–100 mesh
acid-washed Chromosorb W. Three major fatty acids in the neutral lipid fraction comprised 72% of total neutral lipid fatty
acids from young hearts. At sexual maturity (at least 74 days old) C18∶1 was the major fatty acid, followed by C16∶0 and C18∶0. The same three fatty acids comprised 83% of total polar lipid fatty acids, but C18∶0 was the major fatty acid, followed by C16∶0 and C18∶1. The fatty acid composition of dietary lipids influenced the total neutral lipid fatty acid composition of the rat heart,
but had little influence on the fatty acid composition of the polar lipid fraction.
Presented in part at the AOCS Meeting, New Orleans, April 1970. 相似文献
18.
Human aortic smooth muscle cells (SMC) specifically bind and take up indiscriminately both the lipid and protein moietics
of homologous25I-very low density lipoproteins (VLDL) and125I-low density lipoproteins LDL). Sixty-five to 80% of absorbed lipids are incorporated into the cell lipids, preferentially
into the phospholipid fraction. Twenty to 35% of the lipid bound and the protein moiety are eliminated from the cells. Half
of the eliminated protein label is recovered as TCA soluble products. Five mM of p-chlorophenoxyisobutyrate (CPIB) raise the
level of intracellular radioactivity derived from the lipid moieties of VLDL and LDL by about 40% via a reduced elimination.
The processing of the protein moiety and lipoprotein binding to the cell surface are not affected by 5.0 mM of CPIB. CPIB
lowers the incorporation of14C-acetate,14C-pyruvate, and32phosphate radioactivity into fatty acids and phospholipids of aortic SMC. Five mM of CPIB reduce the overall palmitic acid
synthesis by shifting from de novo synthesis to the mechanism of chain elongation, although the further elongation to saturated
C18–C24 fatty acids is also depressed. The CPIB-enhanced retention of the lipid-derived lipoprotein radio-activity is interpreted
as a compensatory mechanism providing cellular fatty acids which are deficient as a result of the CPIB inhibited synthetic
processes. 相似文献
19.
J. G. Hill A. Kuksis J. M. R. Beveridge 《Journal of the American Oil Chemists' Society》1965,42(2):137-141
Short term (16 day) controlled fat (formula type diet) feeding to 10 healthy adult males led to no detectable change in the
total amt or the relative proportions of the individual phospholipids of the red blood cells, although limited changes did
occur in the fatty acids of certain of the phospholipids.
The total phospholipid content of the red blood cells was 315±10 mg/100 ml (average of 20 samples). Lecithin accounted for
34% of the total, with sphingomyelin, phosphatidyl ethanolamine and phosphatidyl serine representing 25, 25 and 16%, respectively.
Approx 36% of the phosphatidyl ethanolamine, 4% of the phosphatidyl serine and 6% of the lecithin was present in the plasmalogen
form.
Each phospholipid class was found to have a distinctive fatty acid spectrum. The M ratio of saturated to unsaturated fatty
acids in all three phosphoglycerides was nearly 1:1. Behenic, lignoceric and nervonic acids made up almost half of the sphingomyelin
fatty acids, and the M ratio of saturated to unsaturated fatty acids in this lipid was 3:1.
When compared with red cells from subjects consuming a diet with a high butter fat content, red cells from subjects on a diet
rich in corn oil were found to contain higher levels of linoleic acid in the lecithin and phosphatidyl serine fractions, and
lower levels of oleic acid in the lecithin fraction. No changes were observed in the fatty acids of the phosphatidyl ethanolamine
and sphingomyelin fractions. It is probable that these alterations represent the result of highly specific exchanges with
plasma fatty acids, and it is suggested that three levels of specificity are involved: class of phospholipid, type of fatty
acid, and specific fatty acid. 相似文献
20.
The triglycerides of the fat globules of sheep and goat milk were isolated and separated into short and long chain lengths
by silicic acid column chromatography. The short chain lengths comprised major triglycerides with 34–44 acyl carbon atoms
and accounted for nearly 50% of the total milk fat. The long chain lengths contained major triglycerides with 40–54 acyl carbons.
Stereospecific analyses of the short chain triglyceride fraction showed that of the 20–23 moles per cent of C4−C8 fatty acids present, at least 95% were specifically attached to the glycerol molecule in the position corresponding to carbon
3 ofsn-glycerol. The distribution of the other fatty acids (C10 or greater) did not show such marked specificity for either the 1 or the 2 position. Although individual triglycerides were
not identified, the specific placement of the fatty acids could best the accounted for by assuming a common pool of long chain
1,2-diglycerides which served as precursors of the bulk of both short and long chain triglycerides during milk fat synthesis.
Presented in part at the AOCS Meeting, New York, October 1968. 相似文献