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1.
C. Bertoli L. B. Fay M. Stancanelli D. Gumy P. Lambelet 《Journal of the American Oil Chemists' Society》1998,75(8):1037-1040
The fatty acid composition, tocopherol and tocotrienol content, and oxidative stability of petroleum benzene-extracted Gevuina avellana Mol (Proteaceae) seed oil were determined. Positional isomers of monounsaturated fatty acids were elucidated by gas chromatography-electron
impact mass spectrometry after 2-alkenyl-4,4-dimethyloxazoline derivatization. This stable oil (Rancimat induction period
at 110°C: 20 h) is composed of more than 85% monounsaturated fatty acids and about equal amounts (6%) of saturated and polyunsaturated
(principally linoleic) fatty acids. Unusual positional isomers of monounsaturated fatty acids, i.e., C16:1 Δ11, C18:1 Δ12, C20:1 Δ11, C20:1 Δ15, C22:1 Δ17, and presumably C22:1 Δ19 were identified. The C18:1 Δ12 and C22:1 Δ19 fatty acids are described for the first time in G. avellana seed oil. While only minute quantities of α-, γ-tocopherols and β-, γ- and δ-tocotrienols were found, the oil contained a
substantial amount of α-tocotrienol (130 mg/kg). The potential nutritional value of G. avellana seed oil is discussed on the basis of its composition. 相似文献
2.
The fatty acid composition and structure of pawpaw fruit (Asimina triloba) triglycerides were examined and found to contain fatty acids ranging from C6 to C20. Octanoate represented 20% of the fatty acids while other medium-chain fatty acids were present in low amounts. Analysis
of the intact triglycerides by high-temperature gas-liquid chromatography gave an unusual three-cycle carbon number distribution.
Analysis of triglyceride fractions separated according to degree of unsaturation suggested that one octanoate was paired with
diglyceride species containing long-chain fatty acids. Determination of the double-bond positions of monoene fatty acids revealed
cis Δ9 and cis Δ11 hexadecenoate and cis Δ9, cis Δ11, and cis Δ13 octadecenoate isomers were present in significant quantities. Octanoate and positional monoene fatty acid isomers were
found only in the fruit lipids and not in the seed lipids. Phenacyl esters of fatty acids were found to be useful derivatives
for structure determination using multiple types of analyses. 相似文献
3.
Isolation and characterization of the monounsaturated long chain fatty acids ofMycobacterium tuberculosis 总被引:2,自引:0,他引:2
The positions of double bond in the monounsaturated C15−C32 fatty acids ofMycobacterium tuberculosis H37Ra were established by gas chromatography/mass spectrometry of the ozonized esters and their pyrrolidide derivatives.
The monounsaturated C15−C21 fatty acids had the double bond primarily at the Δ9 position while the monounsaturated longer chain fatty acids (C22−C32) had the double bond in several positions. Many of the latter acids, especially the odd-numbered series, were very complex
isomeric mixtures. Quantitation showed the most abundant even-numbered long chain fatty acid isomers to be as follow: C22, Δ4; C24, Δ5; C26, Δ7 and Δ9; C28, Δ9; C30, Δ11 and Δ13; C32, Δ13 and Δ15. 相似文献
4.
Néstor M. Carballeira Anthony Sostre Kamen Stefanov Simeon Popov Athanas Kujumgiev Stefka Dimitrova-Konaklieva Carmen G. Tosteson Thomas R. Tosteson 《Lipids》1997,32(12):1271-1275
The fatty acid composition of a new strain of Vibrio alginolyticus, found in the alga Cladophora coelothrix, was studied. Among 38 different fatty acids, a new fatty acid, 9-methyl-10-hexadecenoic acid and the unusual 11-methyl-12-octadecenoic
acid, were identified. Linear alkylbenzene fatty acids, such as 10-phenyldecanoic acid, 12-phenyldodecanoic acid and 14-phenyltetradecanoic
acid, were also found in V. alginolyticus. The alga contained 43% saturated fatty acids, and 28% C16–C20 polyunsaturated fatty acids of the n−3 and n−6 families. 相似文献
5.
Separation of sterol esters from wax esters in the lipids of vernix caseosa and adult human skin surface was accomplished
by column chromatography on MgO. The fatty acids of the sterol esters and wax esters of both samples were separated into saturates
and monoenes, and examined in detail by gas liquid chromatography (GLC). The saturated fatty acids of the wax esters of vernix
caseosa and of adult human skin surface were remarkably similar. They ranged in chain length from at least C11 to C30, six skeletal types being present: straight even, straight odd, iso, anteiso, other monomethyl branched and dimethyl branched.
A large number of patterns of monoenes were observed, each pattern consisting of desaturation of a specific chain at Δ6 or
Δ9 plus its extension or degradation products. The mole per cent of the total Δ6 and Δ9 patterns of wax ester fatty acid monoenes
of vernix caseosa were 87% and 12%, respectively, and 98% and 1%, respectively, for adult human skin surface lipid. The sterol
ester fatty acids of vernix caseosa were much different from those of adult human skin surface: vernix caseosa saturates were
largely branched and of lengths greater than C18, whereas the saturates of adult human surface lipid resembled the wax ester fatty acids. Of the vernix caseosa monoene patterns,
the mole per cent was 30% Δ6 and 70% Δ9, whereas of the adult human skin surface sterol ester fatty acids 89% were Δ6 and
11% Δ9. Chain extension was particularly pronounced in the sterol ester fatty acid monoenes of vernix caseosa amounting to
7–8 C2 units in some cases. The fatty acids of the sterol esters of both vernix caseosa and adult human skin surface appear to be
derived from the sebaceous gland and from the keratinizing epidermis, but those of the wax esters are from the sebaceous glands
only. 相似文献
6.
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
7.
The total lipids of eleven species of Myctophids caught at depths between 20 and 700 m in the northern Pacific Ocean were
analyzed using silicic acid column chromatography (lipid classes) and capillary gas chromatography (fatty acid and fatty alcohol
composition). The major components in the lipid classes were triacylglycerols or wax esters; triacylglycerols were the dominant
acyl neutral lipids (68.1–96.1%) in eight species, and wax esters were found as the dominant lipid (85.5–87.9%) in three species.
The major fatty acids and alcohols contained in the was esters of the three fishes were 18:1n–9, 20:1n–9, 20:1n–11, and 22:1n–11
for fatty acids, and 16:0, 18:1, 20:1, and 22:1 for fatty alcohols. Fatty acids in the triacylglycerols ranging from C14 to C22 were predominantly of even chain length. The major components were 16:0, 16:1n–7, 18:1n–9, 20:1n–11, 22:1n–11, 20:5n–3 (icosapentaenoic
acid), and 22:6n–3 (docosahexaenoic acid). In both the triacylglycerols and the wax esters, the major fatty components were
monoenoic acids and alcohols. It is suggested from the lipid chemistry of the Myctophids that they may prey on the same organisms
as the certain pelagic fishes such as saury and herring, because the large quantities of monoenoic fatty acids are similar
to those of saury, herring, and sprats whose lipids originate from their prey organisms such as zooplanktons which are rich
in monoenoic wax esters. 相似文献
8.
Fatty acid α-hydroxylase from Sphingomonas paucimobilis is an unusual cytochrome P450 enzyme that hydroxylates the α-carbon of fatty acids in the presence of H2O2. Herein, we describe our investigation concerning the utilization of various substrates and the optical configuration of
the α-hydroxyl product using a recombinant form of this enzyme. This enzyme can metabolize saturated fatty acids with carbon
chain lengths of more than 10. The K
m value for pentadecanoic acid (C15) was the smallest among the saturated fatty acids tested (C10–C18) and that for myristic acid (C14) showed similar enzyme kinetics to those seen for C15. As shorter or longer carbon chain lengths were used, K
m values increased. The turnover numbers for fatty acids with carbon chain lengths of more than 11 were of the same order of
magnitude (103 min−1), but the turnover number for undecanoic acid (C11) was less. Dicarboxylic fatty acids and methyl myristate were not metabolized, but monomethyl hexadecanedioate and ω-hydroxypalmitic
acid were metabolized, though with lower turnover values. Arachidonic acid was a good substrate, comparable to C14 or C15. The metabolite of arachidonic acid was only α-hydroxyarachidonic acid. Alkanes, fatty alcohols, and fatty aldehydes were
not utilized as substrates. Analysis of the optical configurations of the α-hydroxylated products demonstrated that the products
were S-enantiomers (more than 98% enantiomerically pure). These results suggested that this P450 enzyme is strictly responsible
for fatty acids and catalyzes highly stereo- and regioselective hydroxylation, where structure of ω-carbon and carboxyl carbon
as well as carbon chain length of fatty acids are important for substrate-enzyme interaction. 相似文献
9.
Unwashed rat liver microsomes were used to study the inhibition of the Δ6 and Δ9 desaturases by cyclopropenoid fatty acids with the ring structure about the 9,10 or 6,7 carbon atoms. The 9,10 cyclopropenoid
acid (sterculic acid) is shown to be an effective inhibitor of only Δ9 desaturase and then only in the presence of MgCl2 and coenzyme A (prepresence of MgCl2 and coenzyme A (presumably due to the formation of sterculoyl-CoA). Two 6,7 cyclopropenoid acids of different chain lengths
showed no marked inhibition of either the Δ6 or Δ9 desaturase. By the use of [3H]-sterculic acid, it has been shown that under conditions of high inhibition of the Δ9 desaturase the inhibitor is not covalently attached to the enzyme at any point. This disproves older ideas on the mechanism
of inhibition that assumed reaction between the cyclopropenoid ring and sulphydryl groups on the enzymes.
Cyclopropenoid fatty acids are named according to the number of carbon atoms in the chain; thus sterculic acid is a C18 cyclopropenoid fatty acid. 相似文献
10.
A. D. Andrade A. F. Rubira M. Matsushita N. E. Souza 《Journal of the American Oil Chemists' Society》1995,72(10):1207-1210
Lipid and fatty acid levels in the edible flesh of 17 freshwater fish from Brazil’s southern region were determined. Analyses
of fatty acid methyl esters were performed by gas chromatography. Palmitic acid (C16:0) was the predominant saturated fatty acid, accounting for 50–70% of total saturated acids. Oleic acid (C18:1θ9) was the most abundant monounsaturated fatty acid. Linoleic acid (C18:2θ6), linolenic acid (C18:3θ3), and docosahexaenoic acid (C22:6θ3) were the predominant polyunsaturated fatty acids (PUFA). The data revealed that species such as truta, barbado, and corvina
were good sources of eicosapentaenoic acid (C20:5θ3) and docosahexaenoic acid (C22:6θ3), and that most freshwater fish examined were good sources of PUFA θ3. 相似文献
11.
The fatty acids and nonsaponifiable lipids ofEimeria tenella oocysts were analyzed by gas liquid chromatography and combined gas liquid chromatographymass spectrometry. The fatty acids
detected were identified as C14∶0, C16∶0, C16∶1, C18∶0, C18∶1, and C18∶2. Though the wt of the fatty acid fraction decreased during sporulation from 91 μg per 106 oocysts to 47 μg per 106 oocysts, the relative amounts of these fatty acids did not change appreciably. The nonsaponifiable lipids ofE. tenella consisted of cholesterol and unbranched primary alcohols of 22, 24, 26, 28, 30, and 32 carbons. Mass fragmentography demonstrated
that each species of alcohol consisted of saturated and monounsaturated derivatives. Trimethylsilyl ethers of fatty alcohols
were found to offer several important advantages over free alcohols for mass spectrometric characterization. Before sporulation,
most fatty alcohols were in the oocyst wall. During sporulation, the wt of the nonsaponifiable lipids increased from 16 μg
per 106 oocysts of 44 μg per 106 oocysts due largely to synthesis of C24 and C26 alcohols. The newly synthesized fatty alcohols were not deposited in the oocyst wall. 相似文献
12.
Comparative studies on the fatty acid composition of moderately and extremely thermophilic bacteria 总被引:11,自引:0,他引:11
The fatty acids of three strains of extremely thermophilic bacteria and three strains of moderately thermophilic bacteria
were examined by gas liquid chromatography. All the thermophiles contained straight, iso, and ante-iso branched fatty acids.
Iso C17∶0 acid was abundant in both the moderately thermophilic strains (10–33%) and the extremely thermophilic strains (50–61%). The
pair of fatty acids iso C15∶0 and iso C17∶0 was the predominant pair in both the moderately (34–64%) and extremely (76–87%) thermophilic strains. The pair of fatty acids
ante-iso C15∶0 and ante-iso C17∶0 was present in larger amount in moderately (25–34%) than in extremely (8.5–15%) thermophilic strains. No hydroxy cyclopropane,
or unsaturated fatty acids were found. One extreme thermophile,Flavobacterium thermophilum HB-8 was grown at 6 different culture temperatures from 49–82 C, and the changes of its fatty acid composition were studied.
The ratios of iso C17∶0/iso C15∶0 and ante-iso C17∶0/ante-iso C15∶0 were much greater at higher culture temperatures, indicating chain elongation. 相似文献
13.
Marine fish have an absolute dietary requirement for C20 and C22 highly unsaturated fatty acids. Previous studies using cultured cell lines indicated that underlying this requirement in
marine fish was either a deficiency in fatty acyl Δ5 desaturase or C18–20 elongase activity. Recent research in turbot cells found low C18–20 elongase but high Δ5 desaturase activity. In the present study, the fatty acid desaturase/elongase pathway was investigated
in a cell line (SAF-1) from another carnivorous marine fish, sea bream. The metabolic conversions of a range of radiolabeled
polyunsaturated fatty acids that comprised the direct substrates for Δ6 desaturase ([1-14C]18∶2n−6 and [1-14C]18∶3n−3), C18–20 elongase ([U-14C]18∶4n−3), Δ5 desaturase ([1-14C]20∶3n−6 and [1-14C]20∶5n−3), and C20–22 elongase ([1-14C]20∶4n−6 and [1-14C]20∶5n−3) were utilized. The results showed that fatty acyl Δ6 desaturase in SAF-1 cells was highly active and that C18–20 elongase and C20–22 elongase activities were substantial. A deficiency in the desaturation/elongation pathway was clearly identified at the level
of the fatty acyl Δ5 desaturase, which was very low, particularly with 20∶4n−3 as substrate. In comparison, the apparent activities
of Δ6 desaturase, C18–20 elongase, and C20–22 elongase were approximately 94-, 27-, and 16-fold greater than that for Δ5 desaturase toward their respective n−3 polyunsaturated
fatty acid substrates. The evidence obtained in the SAF-1 cell line is consistent with the dietary requirement for C20 and C22 highly unsaturated fatty acids in the marine fish the sea bream, being primarily due to a deficiency in fatty acid Δ5 desaturase
activity. 相似文献
14.
The steryl ester and phospholipid fractions of the marine spongeAgelas conifera were isolated and analyzed. The fatty acyl components of the steryl ester and phospholipid fractions as determined by gas
chromatography and gas chromatography/mass spectrometry were very similar and consisted of 56.8 and 62.7% of C14−C20 acids (normal; branched, especiallyiso andanteiso; and monounsaturated, particularly Δ9 and Δ11 acids) and of 43.1 and 35.5% of C24−C26 acids (Δ5,9 diunsaturated acids), respectively. The major constituent fatty acids detected were 13-methyltetradecanoic,n-hexadecanoic, 10-methylhexadecanoic, 11-octadecenoic, 12-methyloctadecanoic, 5,9-pentacosadienoic and 5,9-hexacosadienoic
acids. The phospholipids isolated were identified as phosphatidylcholine (37%), phosphatidylserine (34%), phosphatidylethanolamine
(16%) and phosphatidylinositol (11%). The distribution of fatty acids within the phospholipid classes was also determined. 相似文献
15.
Two unusual lipid classes were detected by thin-layer chromatography in the neutral lipids derived from goat cauda-epididymal
sperm plasma membrane. The lipids were identified as wax esters and 1-O-alkyl-2,3-diacylglycerols based on chromatographic properties, identity of their hydrolysis products, and infrared/1H nuclear magnetic resonance spectral evidence. The membrane containedca. 3 and 5 μg/mg protein of wax esters and alkyldiacylglycerols, respectively. The relative proportions of wax esters and alkyldiacylglycerols
in the total neutral lipids were 1.5% and 2.4%, respectively. The lipids contained fatty acids with chain lengths of C14 to C22. The major fatty acids of the wax esters were 14∶0, 16∶0, 16∶1ω7, 18∶0 and 18∶1ω9. The fatty acids in alkyldiacylglycerol
were 16∶0, 18∶0, 22∶5ω3 and 22∶6ω3. Alkyldiacylglycerol was particularly rich in docosahexaenoic acid 22∶6ω3) representing
30% of the total fatty acids. The alcohols of wax ester were all saturated with C20–C29 carbon chains. The deacylated products derived from alkyldiacylglycerols were identified as hexadecyl, octadecyl and octadec-9′-enyl
glycerol ethers. 相似文献
16.
The changes in the triacylglycerol (TAG) composition of colostrum fat of three cows were studied. In addition to the determination
of fatty acid composition by gas chromatography, the distribution of TAG according to the acyl carbon number (ACN) and molecular
weight was analyzed utilizing both supercritical fluid chromatography (SFC) and ammonia negative-ion chemical ionization mass
spectrometry (MS). Colostrum TAG contained substantially less stearic and oleic acids and more myristic and palmitic acids
than the normal Finnish milk fat. The major trends in the changes of fatty acids and TAG were similar for each cow, although
clear differences between individuals were found. During the first week of parturition, the proportions of short-chain fatty
acids (C4–C10) typically increased as well as those of stearic and oleic acids, whereas the relative amounts of C12–C16 acids decreased, especially those of myristic and palmitic acids. Distinct changes occurred also in TAG distributions: the
proportions of molecules with ACN 38–40 increased and those with ACN 44–48 decreased. Although there were distinct differences
between individuals shortly after delivery, both the fatty acid compositions and TAG distributions of the milk samples of
the cows started to resemble each other after one week. The theoretical profiles of colostrum TAG calculated based on the
fatty acid compositions differed clearly from the ACN distributions analyzed by SFC and MS. Thus, the analysis of TAG is essential,
because the changes in molecular species composition of colostrum TAG cannot be estimated according to the fatty acid analysis
alone. 相似文献
17.
Tris isovalerate-supplementedTetrahymena pyriformis W showed no qualitative change in fatty acid composition; however, an increase in polar lipids that contain odd numbered
iso acids (C13, C15, C17, C19) occurred. This change was accompanied by a decrease in the proportional amount of even numbered normal acids (C14, C16, C18). The neutral and polar lipids from cells incubated with [1-14C] isovaleric acid were found to contain radioactivity. The methyl esters of the saturated fatty acids obtained from the polar
lipids by alkaline methanolysis were separated by reversed phase chromatography, the identities confirmed by gas chromatography-mass
spectrometry, and the specific activities determined. Iso acids were found to be the most heavily labeled materials. In addition
to ceramide, two sphingolipid components were detected. One yielded saturated fatty acids after acidic methanolysis, while
the other contained >93% α-hydroxy fatty acids. Radioactivity was noted in the long chain base fraction derived from the sphingolipids.
Progressive growth inhibition occurred as the isovalerate concentration was increased in the culture medium; however, the
ciliates were morphologically indistinguishable from unsupplemented cells. 相似文献
18.
The neutral lipids of the skin from the feet of turkey poults fed a biotin supplemented or a biotin deficient diet consist
mainly of triacylglycerols, and of mono- and diester waxes. Diester waxes from both groups were characterized as fatty acid
esters oferythro-2,3-alkanediols. A comparison between fatty acid composition of the two groups, however, revealed the following significant
differences. Biotin deficient birds showed a fairly high concentration of very long chain fatty acids (C36–C40) which were completely absent in biotin supplemented birds. Further, almost one-third of the fatty acids of diester waxes
in biotin deficient birds were unsaturated while those from biotin supplemented birds were predominantly (96%) saturated. 相似文献
19.
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
20.
Pigeon “milk” (PM) collected from the crop of 1- to 5-day-old squabs was analyzed to examine whether there were changes in
lipid composition during the first week of secretion. The high PM fat content (9–11%) remained fairly constant in the first
5 days of secretion. The mean percentage of neutral lipids, glycolipids and phospholipids was 80, 12 and 8%, respectively.
Unlike the content of neutral lipids, glycolipid and phospholipid levels increased significantly between day 1 and day 5 of
secretion. Triglycerides, the major neutral lipids, decreased by 24% between day 1 and day 5, while free sterols, monoglycerides
and hydrocarbons increased by 8%, 11% and 2.5%, respectively, during the same period; diglycerides and sterol esters, however,
remained unchanged. The ratio of saturated to unsaturated fatty acids was 0.27 and it remained unchanged. Medium-chain (C10, C12 and C14) and oddchain (C15 and C17) fatty acid contents were low. Fatty acids longer than C20 were absent. Palmitic acid, the major saturated fatty acid, increased by 42% from day 1 to day 5, whereas stearic acid decreased
by 48% during the same period. Oleic acid, the predominant unsaturated fatty acid, also decreased from 51 to 45% between the
first and fifth day of PM secretion. Polyunsaturated acids (18∶2, 18∶3 and 20∶4) accounted for 26% and 30% of the total fatty
acids on day 1 and day 5, respectively. Although lipid changes in the crop of squabs prior to collection of samples cannot
totally be ruled out, the nature of lipid changes is likely to reflect cellular breakdown that precedes PM secretion by parent
pigeons. 相似文献