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1.
Five ganglioside fractions from bovine adrenal medulla were analyzed with respect to their fatty acid and long chain base
compositions. The five fractions included two hematosides and three hexasamine-containing species, the latter having chromatographic
properties comparable to the major gangliosides of brain. The fatty acid compositions of all five were similar: 22∶0 was the
most abundant, but significant amounts of 16∶0, 18∶0, 24∶0 and 24∶1 were also present. No hydroxy fatty acids were detected.
The principal long chain base in each fraction was 4-sphingenine (sphingosine), with lesser amounts of the C16 and C17 homologues. Minor quantities of the corresponding saturated bases were also detected. These were identified by two gas liquid
chromatography methods: (a) trimethylsilyl ether derivatives, (b) aldehydes formed by periodate oxidation of the long chain
bases. No 4-eicosasphingenine (C20-sphingosine), characteristic of brain gangliosides, was found in any of the fractions. The results demonstrate that gangliosides
of the adrenal medulla show tissue specificity in fatty acid and long chain base composition which is independent of carbohydrate
structure. 相似文献
2.
The phospholipid composition was determined for the amebocyte of the primitive arthropod Limulus polyphemus. The total fatty acid composition of the cells' lipids was analyzed by gas chromatography/mass spectrometry (GC/MS) of fatty
acid methyl esters (FAME). The FAME analysis revealed high levels of 20-carbon polyunsaturated fatty acids (PUFA), especially
arachidonic (20∶4n-6) and eicosapentaenoic (20∶5n-3) acids. Almost 20% of the total lipid profile was comprised of dimethyl
acetals of 16- to 20-carbon chain lengths, indicative of plasmalogens in the phospholipid pool. Phospholipids, analyzed by
high-pressure liquid chromatography, included phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine
(PS), phosphatidylinositol (PI), sphingomyelin (SPH), and cardiolipin (CL). PE and PC levels predominated at 42.2 and 36.3%,
respectively. Smaller amounts of PS (9.0%) and PI (6.2%) were present, as well as low levels of SPH (4.6%), CL (1.6%), and
trace amounts of lysophosphatidylcholine. The major phospholipid species, PE, PC, PS and PI, were collected and their molecular
species were examined by electrospray-ionization mass spectrometry. The molecular species within the phospholipid classes
reflected the high levels of PUFA seen in the total lipid profile. PI was mainly composed of 18∶0a/20∶4. Over half of the PS consisted of 18∶0a/18∶1 and 18∶0a/20∶4. The major PE species were 20∶1p/20∶5, 20∶1p/20∶4, 18∶0p/20∶5, and 18∶0p/20∶4. PC had the largest distribution of molecular species, and its most abundant species were 16∶0e/20∶5, 16∶0e/20∶4, and 16∶0p/20∶4. The presence of 16∶0e/20∶4 is the first documentation of a specific precursor to platelet-activating factor in an invertebrate hemocyte. Note:
at the sn-1 position: [a=1=O-acyl, e=1-O-alkylether, and p=1-O-alk-1′-enyl (plasmalogen)]. 相似文献
3.
The influence of long duration rapeseed oil feeding with high or low levels of erucic acid has been investigated on rat heart
phospholipids. The rats treated for 20 wk with rapeseed oil containing 46.2% erucic acid showed a twofold increase in the
sphingomyelin content of the heart. Treatment with primor rapeseed oil (3.7% erucic acid) for 20 wk did not modify phospholipid
composition of rat heart. The fatty acid patterns of phosphatidylethanolamine and phosphatidylcholine were slightly influenced
by the high erucic rapeseed oil; eicosenoic acid was incorporated preferentially into position one, but erucic acid showed
a random distribution in both. After high erucic rapeseed oil feeding, 22∶1 was incorporated into cardiolipin (5.6%) and sphingomyelin
(10.5%). The incorporation of 22∶1 into sphingomyelin was associated with an increase of the percentage of 24∶1 (14.6%) and
a decrease of saturated long chain fatty acid (22∶0, 24∶0) percentages. Primor rapeseed oil caused a slight increase of 24∶1
and a decrease of 22∶0 and 24∶0 in rat heart sphingomyelin. As cardiolipin is localized in the inner membrane of mitochondria
and sphingomyelin in plasma and microsomal membranes, the acyl-moiety alterations of both phospholipids might be correlated
to the pathological lesions of rat heart after a long duration of rapeseed oil feeding. 相似文献
4.
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
5.
Grace Y. Sun 《Lipids》1979,14(11):918-924
The phospholipid composition and their acyl group profiles from subcellular fractions of guinea pig adrenal gland and the
same fractions from the cortex and medulla of the bovine gland were compared. The phospholipids of guinea pig adrenal were
enriched in diacyl-glycerophosphocholines (GPC) which comprised over 50% of the total phospholipids, but the proportions of
ethanolamine and choline plasmalogens, sphingomyelin and diacyl-glycerophosphoserine (GPS) were lower in guinea pig adrenals
as compared to the bovine adrenals. In the bovine adrenal, sphingomyelin and diacyl-GPS were enriched in the medulla, whereas
diacyl-glycerophosphoinositol (GPI) were enriched in the cortex. Although lysolecithin was present (up to 4.5%) in the bovine
adrenal, only trace amounts of this lipid were detected in the guinea pig adrenal. Characteristic acyl group profiles were
found associated with each type of the phosphoglycerides in adrenal membranes. However, acyl group profiles of the phosphoglycerides
were not greatly different either between the bovine and guinea pig adrenal or with respect to the type of subcellular membranes
isolated. Diacyl-GPC were enriched in 16∶0 and 18∶1, but also contained considerable amounts of 18∶0, 18∶2 and 20∶4. Diacyl-GPE
were enriched in 18∶0, 18∶1 and 20∶4, while diacyl-GPI, diacyl-GPS, as well as alkenylacyl-GPE, were enriched in 20∶4. The
lysolecithin from bovine adrenal membranes contained mainly 16∶0, 18∶0 and 18∶1 with only trace amounts of the polyunsaturated
fatty acids. Other polyunsaturated fatty acids, such as 22∶4 and 22∶6, are apparently not prominent in the phosphoglycerides
from either the bovine or the guinea pig adrenal gland. 相似文献
6.
Male Sprague-Dawley rats were fed for 8 weeks a corn oil (CO) diet or a hydrogenated coconut oil (HCNO) diet. These diets
were fed in the absence or presence of eicosa-5,8,11,14-tetraynoic acid (TYA). The inclusion of TYA in the HCNO diet reduced
the levels of 12∶0 and 14∶0 in the total fatty acids of livers and plasma. With either diet, the presence of TYA caused an
alteration in the fatty acid composition of these tissues so as to reduce the values of the ratios: 16∶1/16∶0, 18∶1/18∶0,
and 20∶4/18∶2. These results suggest that dietary TYA can influence the hepatic metabolism of medium chain fatty acids and
that it may inhibit the desaturase enzyme involved in the synthesis of not only 20∶4 but also of monoenoic fatty acids. 相似文献
7.
Two groups of rats were fed diets containing 20% by weight of either partially hydrogenated marine oil supplemented with sunflower
seed oil (PHMO) or palm oil (PO) for 8 wk. Using a liver perfusion system, the effect of dietary long chain monoenoic fatty
acids on the uptake and metabolism of [14-14C]erucic acid was studied. The perfusion times were 15 and 60 min, respectively. The two groups showed equal ability for erucic
acid uptake in the liver but differed in the channeling of the fatty acids into various metabolic pathways. A higher metabolic
turnover of 22∶1 in the PHMO livers relative to the PO livers was demonstrated by an increased recovery of total [14C]labeling in the triglyceride (TG) and phospholipid (PL) fractions, already evident after 15 min of perfusion. The chainshortening
capacity was highest in the PHMO group, reflected by a higher [14C]18∶1 incorporation in both TG and PL, and increasing from 15 to 60 min of perfusion. The amount of [14C]18∶1 found in PL and TG after 60 min of perfusion of livers from rats fed PO corresponded to that shown for the PHMO group
after 15 min. The PL demonstrated a discrimination against 22∶1 compared to TG, and, when available, 18∶1 was highly preferred
for PL-synthesis.
The total fatty acid distribution in the TG, as determined by gas liquid chromatography (GLC), reflected the composition of
the dietary fats. In the total liver PL, 22∶1 and 20∶1 were present in negligible amounts, although the PHMO diet contained
12–13% of both 22∶1 and 20∶1. In the free fatty acid fraction (FFA), the major part of the radioactivity (≈80%) was [14-14C]erucic acid, and only small amounts of [14C]18∶1(<2%) were presents, even after 60 min of perfusion. The shortened-chain 18∶1 was readily removed from the FFA pool
and preferentially used for lipid esterification. 相似文献
8.
The lipid concentration and fatty acid composition of the whole liver and of cultured hepatocytes isolated from the livers
of rats fed ad libitum (fed), fasted for 24 hr (fasted), or fasted for 48 hr and then refed a fat-free, high carbohydrate
diet for 48 hr (refed) was studied. Hepatocytes were maintained as monolayer cultures in serum-free, lipid-free media and
their fatty acid composition was analyzed at 3, 24, 48, 72 and 96 hr. The livers of fed animals, as well as their hepatocytes,
contained less total lipid than those from animals on either of the other dietary regimes. Livers of fasted animals had three
times the amount of lipid found in the livers of fed animals, and the livers of refed animals contained five times the amount
of lipid as the livers of fed animals (all based on mg lipid/g wet weight of liver). The fatty acid composition of hepatocytes
after 3 hr of culturing was very similar to that of fresh liver when compared in each of the dietary regimes. However, while
the fatty acid compositions of livers and hepatocytes from fed and fasted animals were similar, the pattern in liver of refed
animals was quite distinct from that of the fed animals. In the fed and fasted animals palmitic acid (16∶0), stearic acid
(18∶0), oleic acid (18∶1[n-9]), linoleic acid (18∶2[n-6]) and arachidonic acid (20∶4[n-6]) were the major fatty acids of the
liver; in refed animals 16∶0, palmitoleic acid (16∶1[n-7]), 18∶0, 18∶1(n-9) andcis-vaccenic acid (the n-7 isomer of oleic acid) were the major fatty acids. During maintenance in culture the 18∶1(n-9) content
of the hepatocytes increased in cells from livers of animals on all three dietary regimes. The polyunsaturated fatty acid
content was similar in fresh livers and isolated hepatocytes in all samples when compared on the basis of μg fatty acid/mg
of hepatocyte or liver protein. It was also found that the polyunsaturated fatty acid content of hepatocytes was remarkedly
stable with time of culture when the cells were incubated in serum-free, lipid-free medium. Thus, isolated hepatocytes maintained
in serum-free medium appear to be a possible system for the evaluation of the effects of prior nutritional status on fatty
acid metabolism in the whole animal, not subject to hormonal and other somatic influences which often complicate the interpretation
of such nutritional studies. 相似文献
9.
Phospholipid classes were separated from mouse brain lipid extracts by preparative thin-layer chromatography (TLC). Methyl
esters were prepared from the intact phospholipids by direct transesterification at room temperature in the presence of silica
gel by using 0.5m NaOH-methanol in order to prevent interference by aldehydes or derivatives. Dimethyl acetal derivatives of phosphoglyceride
alkenyl ethers (alkenyl moiety with a double bond in 1,2-position relative to oxygen linkage) were prepared, using 5% concentrated
HCl in methanol, followed by preparative TLC for isolation.
The major phospholipids present were ethanolamine phosphoglycerides (EPG) 39.8%, choline phosphoglycerides (CPG) 39.7%, serine
phosphoglycerides (SPG) 15.0%, and sphingomyelin (Sph) 5.4%. One-fifth of the total phospholipids (PL) were in the form of
plasmalogens, mainly EPG. Choline and serine plasmalogens were present in trace quantities. The major aldehyde components
of the plasmalogens were 16∶0, 18∶0, and 18∶1.
The EPG were rich in long-chain poly-unsaturated fatty acids, including 28.8% of 22∶6 and 17.0% of 20∶4, but contained only
7.2% of 16∶0. In contrast, the CPG contained 39.6% of 16∶0, and 31.0% of 18∶1 with a small content of polyunsaturated fatty
acids. The SPG exhibited a still different pattern containing 38.2% of 18∶0, 23.2% of 18∶1, 24.3% of 22∶6, 2.9% of 16∶0, and
3.8% of 20∶4.
Presented in part at the AOCS Meeting, New Orleans, May 1967. 相似文献
10.
Amniotic fluid collected from 14 normal and 11 diabetic patients was analyzed for phospholipids, and separated sphingomyelin
and lecithin fractions were further studied for their fatty acid composition by gas liquid chromatography. Notable differences
in percent fatty acid composition of sphingomyelin were observed for palmitic (16∶0; diabetic < normal), oleic (18∶1; diabetic
> normal), behenic (22∶0; diabetic < normal) and arachidic acid (20∶0; absent in diabetics) in the specimens studied. Notable
differences were not observed in fatty acids from lecithin fraction. Fatty acid composition of sphingomyelin from amniotic
fluid is similar to fatty acid distribution in sphingomyelin from serum and erythrocyte and suggests maternal origin of the
lipid.
Presented in part at the 67th annual meeting of the Federation of American Societies for Experimental Biology, Chicago, IL
1983.
Abstracted from dissertation written by one of the authors (Vicki Brooks) in partial fulfillment for Master of Science degree
in Clinical Chemistry, Department of Pathology, LSU Medical Center. 相似文献
11.
The effect of diets high (15%) in saturated (beef tallow) or polyunsaturated (corn or cottonseed oil) fatty acids on the fatty
acid composition of sphingomyelin from canine erythrocytes and platelets and sphingomyelin and neutral glycosphingolipids
of swine erythrocytes was determined. Sphingolipids of platelets and erythrocytes from animals fed high levels of corn or
cottonseed oil exhibited a dramatic alteration in their fatty acid composition, most notable of which was a 50% reduction
in nervonic acid (24∶1ω9) as compared to levels observed in control or tallow fed animals. This decrease was compensated for
by a quantitatively similar increase in a C24 dienoic acid. The long chain dienoic acid was isolated by silver nitrate thin layer chromatography and determined by analysis
of its oxidation products to be Δ15, 18-tetracosadienoic acid (24∶2ω6). When the animals were fed the diets high in polyunsaturates,
the 24∶2ω6 represented 13, 20, and 9% of the sphingomyelin fatty acids from canine erythrocytes, platelets, and swine erythrocytes,
respectively, and 5% of the neutral glycosphingolipid fatty acids of swine erythrocytes. In contrast, the 24∶2ω6 represented
less than 4% of the total cellular sphingolipid fatty acids in animals fed the control or high beef tallow diets. The 24∶1ω9
in the sphingolipids of the animals fed the polyunsaturated diet was roughly equal to that of 24∶2ω6, whereas in the sphingolipids
of animals fed the control or saturated fat (beef tallow) diet, the 24∶1ω9 was twice these values. Since sphingomyelin is
a membrane component, the increase in unsaturation (24∶2ω6) in its fatty acid moiety induced by dietary polyunsaturates may
affect membrane fluidity and may alter membrane properties.
Dr. Nelson’s current affiliation is with the Lipid Metabolism Branch, Division of Heart and Vascular Diseases, National Heart,
Lung, and Blood Institute. 相似文献
12.
Sheila M. Innis Roger Dyer Louis Wadsworth Paul Quinlan Deborah Diersen-Schade 《Lipids》1993,28(7):645-650
Platelet lipid composition is important to normal platelet morphology and function, and is influenced by dietary fatty acids
and cholesterol. The fatty acid composition and cholesterol content of infant formulas differs from those of human milk, but
the possible effects on platelet lipids in young infants is not known. This was studied in piglets fed from birth to 18 d
of age with one of eight formulas differing in saturated fatty acid chain length, or content of 18∶1, 20∶5n−3 plus 22∶6n−3,
or cholesterol. A reference group of piglets fed sow milk was also studied. Sow milk has a fatty acid composition and cholesterol
content similar to that of human milk. Piglets fed formulas high in 18∶1 (34.9–40.8% wt fatty acids) and low in 16.0 (≤6.5%
wt fatty acids) had lower platelet counts and greater platelet size than piglets fed sow milk (40.4% 18∶1, 30.7% 16∶0). Piglets
fed formulas high in 16∶0 (27–29.6%) and 18∶1 (40–40.6%), or low in both 16∶0 (5.9–6.1%) and 18∶1 (10.8–11.2%), had similar
platelet counts and size to piglets fed sow milk. Platelet phospholipid % 20∶4n−6 was lower in all the groups of piglets fed
formula than in the group fed sow milk. Addition of fish oil with 20∶5n−3 plus 22∶6n−3 to the formula further decreased platelet
phospholipid 20∶4n−6. Addition of cholesterol to the formula increased the platelet phospholipid % 20∶4n−6 and platelet volume. 相似文献
13.
Small quantities of long chain fatty alcohols (esterified or free or both) were found in four normal tissues (about 0.01%
of total neutral lipids) and three neoplasms (about 0.3% of total neutral lipids). The major chain lengths (16∶0, 18∶0 and
18∶1) of the fatty alcohols in both normal and neoplastic cells qualitatively resemble the O-alkyl chain lengths of glyceryl
ethers. Our data showing that long chain fatty alcohols occur in vivo support the biological significance of the metabolic
pathway that uses fatty alcohols as a substrate for the alkyl chain in glyceryl ether biosynthesis. 相似文献
14.
The individual molecular species composition of diacyl, alkylacyl and alkenylacyl glycerophospholipids was determined in mouse
peritoneal macrophages. A marked deterogeneity in the relative composition (mol%) of macrophage ether and ester phospholipid
individual species was noted. High concentrations of 16∶0–20∶4 were found in ether phospholipids such as alkenylacyl glycerophosphoethanolamine
(GPE; 27.5 mol%) and alkylacyl glycerophosphocholine (GPC; 16.6%) as compared to mol % levels of 16∶0–20∶4 in diacyl GPE (5.7%)
and diacyl GPC (8.1%), respectively. Interestingly, alkenylacyl GPE was highly enriched in 1-ether (16∶0) relative to alkylacyl
GPC. The predominant diacyl molecular species in glycerophosphoinositol (GPI) and glycerophosphoserine (GPS) were 18∶0–20∶4
(59.1%) and 16∶0–18∶1 (41.1%), respectively. It is noteworthy that the level of 18∶0–20∶4 was several times higher in diacyl
GPI (59.1%) than in diacyl GPS (11.1%), diacyl GPE (25.7%), and diacyl GPC (3.7%). The most abundant molecular species in
diacyl GPC and diacyl GPE were 16∶0–18∶1 (29.9%) and 18∶0–20∶4 (25.7%), respectively. The abundance of 20∶4 in ether phospholipids,
specifically 16∶0–20∶4 and 18∶0–20∶4, in alkylacyl GPC is significant in view of the role these antecedents play in the biosynthesis
of platelet-activating factor (PAF) and 20∶4-derived eicosanoids in stimulated macrophages. The unique molecular species composition
of the peritoneal macrophage distinguishes this cell type from others. 相似文献
15.
Nakagawa Yasuhito Waku Keizo Hirose Akihiko Kawashima Yoichi Kozuka Hiroshi 《Lipids》1986,21(10):634-638
The effect of administeringp-chlorophenoxyisobutyric (clofibric) acid to rats on the molecular species composition of diacyl-glycerophosphocholine (GPC)
of rat liver microsomes was studied. Microsomal choline glycerophospholipids were converted to 1,2-diradyl-3-acetylglycerol
and were separated into molecular species by reverse-phase high performance liquid chromatography. Diacyl-GPC consisted of
17 different molecular species. The predominant species were arachidonoyl derivatives, such as 18∶0–20∶4 (22.2% of the total)
and 16∶0–20∶4 (22.0%). Administration of clofibric acid to rats caused a marked increase in 16∶0–18∶1 species of diacyl-GPC
from 8% to 30%, making these the predominant species of diacyl-GPC in clofibric acid-fed rats. Also, a significant decrease
(50% of controls) in 18∶0–18∶2 and 18∶0–20∶4 species was observed, whereas the decrease in molecular species containing 16∶0
at the 1-position such as 16∶0–18∶2 and 16∶0–20∶4 was small (approximately 85% of control). The results show that clofibric
acid caused marked changes in the molecular species composition of diacyl-GPC. The participation of 1-acyl-GPC acyltransferase
and stearoyl-CoA desaturase in the regulation of the molecular species composition of diacyl-GPC is discussed. 相似文献
16.
The total lipids and fatty acid composition ofEntomophthora coronata were determined. The fungus was grown on a chemically defined medium and a chemically nondefined medium (Sabouraud dextrose
yeast extract) for a period of 26 days. The organism contained from 16.2% to 44.6% total lipids depending upon the days of
growth. The major fatty acids were 12∶0 (5.5–9.0%), 13∶0 (1.2–8.2%), 14∶0 (33.5–43.5%), 16∶0 (9.7–13.9%), 18∶19 (20.4–22.4%), and 18∶29,12 (3.5–10.5%). Lesser amounts of 15∶0, 16∶1, 16∶2, 17∶0, 18∶0, two other 18∶2 (both having conjugated double bonds), 18∶36,9,12, another 18∶3 (conjugated double bonds), 20∶38,11,14, 20∶45,8,11,14, another 20∶4 (conjugated double bonds), and 24∶1 acids were found. Trace amounts of 20∶0, 20∶1, 20∶2, 22∶0 and 24∶0 were
also present. The relative percentage of most of the fatty acids did not vary appreciably with growth. However, 18∶29,12 and 20∶45,8,11,14 increased with age of the chemically defined culture. Peak E (18∶2, conjugated double bonds) increased and 13∶0 and 18∶36,9,12 decreased with age of the chemically nondefined culture. The fatty acids were predominately saturated (56.9–69.1%) and contained
a high percentage of shorter chain fatty acids (C 12 to C 15). The fatty acids of the chemically defined culture were more
unsaturated than the Sabouraud culture and the unsaturation increased with age of the culture. 相似文献
17.
The fatty chain compositions of 1-O-alk-1′-enyl-2-acyl, 1-0-alkyl-2-acyl, and 1,2-diacyl glycerophospholipids of the Japanese oysterCrassostrea gigas (Thunberg) were investigated. Major fatty chains in thesn-1 position of 1-alk-1′-enyl-2-acyl ethanolamine phospholipids (EPL) were 18∶0 (64.7%) and 20∶1 (11.1%). Majorsn-1 chains of alkenylacyl choline phospholipids (CPL) were 18∶0 (63.3%) and 16∶0 (22.2%). In the case of 1-alkyl-2-acyl EPL,
the predominant fatty chains in thesn-1 position were 18∶0 (51.5%), 16∶0 (16.0%) and 20∶1 (12.5%); in the case of 1-alkyl-2-acyl CPL, the majorsn-1 chains were 16∶0 (44.0%) and 14∶0 (23.4%). Saturated fatty chains were predominant in both EPL and CPL. Prominent fatty
acids in thesn-2 position of the alkenylacyl EPL were 22∶6n−3 (29.0%), 20∶5n−3 (19.0%) and 22∶2 NMID (non-methylene interrupted dienes,
16.6%) contributing to about 65% of the total fatty acids, while alkenylacyl CPL was rich in the saturated acids 16∶0 (32.0%)
and 18∶0 (9.2%). In the alkylacyl EPL, 16∶0, 18∶1n−9, 18∶0 and 16∶1n−7 were prominentsn-2 fatty acids and accounted for 30.6%, 10.0%, 9.8%, and 8.3%, respectively. Polyunsaturated fatty acids were detected, but
were present at extremely low percentages. Majorsn-2 fatty acids in alkylacyl CPL were 16∶0 (25.4%), 22∶6n−3 (16.0%) and 20∶5n−3 (8.4%). The major fatty acids of diacyl EPL
were 20∶5n−3 (22.3%), 16∶0 (17.9%), and 18∶0 (16.1%), and those of diacyl CPL were 16∶0 (30.4%), 20∶5n−3 (17.6%) and 18∶1n−7
(7.4%). 相似文献
18.
Feeding an oil from Lunaria biennis rich in 22∶1n−9 and 24∶1n−9 to homozygous quaking (qk.qk) mice caused a large increase in the percentage of 24∶1n−9 and corresponding
decreases in the percentage of 24∶0 and 22∶0 in sphingomyelins from liver, erythrocytes, and milk. Brain sphingomyelin from
2-wk-old qk.qk pups born to qk.qk mothers maintained on the Lunaria oil had essentially normal percentage of 24∶1n−9 and 18∶0, in contrast to pups born to mothers maintained on a control oil
rich in 18∶1n−9 whose brain sphingomyelin had a markedly reduced percentage of 24∶1n−9 and an increased percentage of 18∶0.
After 2 wk and up to and beyond weaning, the qk.qk pups from Lunaria-fed mothers weaned on to the Lunaria diet had a markedly decreased percentage of 24∶1n−9 in their brain sphingomyelin, accompanied by an increased percentage
of 18∶0, as compared to heterozygous quaking mice. However, the percentage of 24∶1n−9 in brain sphingomyelin in qk.qk pups
weaned on to the Lunaria diet continued throughout this period (2–8 wk postbirth) to be significantly higher than in qk.qk pups weaned on to the control
diet. We conclude that dietary 24∶1n−9 influences the fatty acid composition of brain sphingomyelin in qk.qk mice, but only
via the mother in pre- or early postnatal animals. We further consider that the dietary effects may be elicited mainly in the
sphingomyelin of nonmyelinated brain cells, and that the nervonic acid in myelin sphingomyelin may be formed mainly by chain
elongation in oligodendrocytes from shorter chain fatty acid precursors. 相似文献
19.
The effect of the water-soluble fraction (WSF) of crude oil on lipid contents, lipid classes, FA, and PC molecular species
was studied in high-phospholipid (hepatopancreas) and low-phospholipid (egg) tissues of a freshwater crustacean. After a 21-d
exposure to a sublethal concentration of WSF, a significant decrease in shrimp total lipids was observed, although no alterations
could be detected in the hepatopancreas or egg lipid contents. TAG/phospholipid ratios increased in the hepatopancreas and
decreased in the eggs, suggesting alterations either in the mobilization of TAG to phospholipid pools or in the energy balance.
The FA composition of phosphoglycerides in the hepatopancreas and eggs was dominated by PUFA, whereas the n−3/n−6 ratio was
not affected by WSF exposure, although there was a significant increase in hepatopancreas 18∶1n−9. Analysis of the PC molecular
species by HPLC-ELSD showed the presence of 15 species, with 16∶0/18∶1, 18∶1/18∶2, 16∶0/20∶5, and 16∶1/20∶5 being the major
species in the hepatopancreas. The PC molecular species in the eggs showed a different pattern, dominated by 16∶0/18∶1 and
18∶1/18∶2. Of the PC molecular species, 10 contained 22∶6n−3, 20∶5n−3, and 20∶4n−6. Small amounts of di-PUFA species were
also found. Exposure to WSF altered the PC molecular species in both tissues. The four major hepatopancreas molecular species
and most of the ones containing PUFA decreased. This was compensated for by an increase in 16∶1/18∶1 (152%) and 18∶1/18∶1
(50%). The two major egg PC molecular species decreased, whereas the PUFA-containing ones increased. The contrasting responses
of both tissues of WSF contamination suggests the presence of different homeostatic mechanisms. 相似文献
20.
The content and composition of neutral lipids and phosphoglycerides from full-grown prophase-arrestedBufo arenarum Hensel oocytes and from their ghost preparations were studied. The ghosts obtained are highly enriched in plasma membrane
as suggested by the activity of 5′-nucleotidase, a marker enzyme, and the level of typical membrane components such as sphingomyelin,
phosphatidylserine (PS), phosphatidylinositol (PI), and phosphatidic acid. In whole oocytes, triacylglyceride (TAG) comprises
about 60% of the total lipids followed by phosphatidylcholine (PC), cholesterol, and phosphatidylethanolamine (PE). TAG and
diacylglycerides have a similar unsaturation index. PC and PE account for about 80% of the phosphoglycerides in the whole
oocyte and in their plasma membrane-enriched fractions. Arachidonic acid (20∶4n−6), 18∶0, and 16∶0 make up about 80 mol% of
the total fatty acids in Pl in whole oocytes and ghost fractions. The unsaturation index in PS is higher in intact oocytes
than in ghost preparations, probably owing to the significant amount of 20∶4n−6 which comprises 23 mol% of the total fatty
acids in whole oocytes. The fatty acid profile in phosphatidic acid from whole oocytes is rather different from that in ghosts.
Sphingomyelin contains mainly saturated and monounsaturated fatty acids, 24∶1 being the principal very long chain unsaturated
fatty acid in both oocytes and ghosts. 相似文献