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1.
Sreerama Shetty  S. N. Hegde 《Lipids》1991,26(11):930-933
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   

2.
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   

3.
The distribution of total and free fatty acids as well as the acids from the glycerides, sterol esters and phospholipids of polar bear liver lipids was ascertained and found to contain somewhat higher levels of unsaturated components as compared to those of such mammals as the pig. Saponification of the liver lipids yielded the hydrocarbons, alcohols and sterols which were analyzed by GLC. The hydrocarbons occurred at an overall level of 55 mg/kg liver or 57.9 mg/100 g total lipids, of which pristane and other saturated hydrocarbons, mainly normal homologs, comprised 2.6 and 5.3 mg/100 g, respectively; the remainder contained squalene (37.7 mg/100 g) and other unsaturated types (12.3 mg/100 g). As based on the total lipids, the levels of fatty alcohols, sterol and glyceryl ethers amounted to 1.65%, 5.9% and 0.03%, respectively. The fatty alcohols displayed about 31 peaks of C12 to C30, of which the hexadecanol and a branched C20 component were prominent.  相似文献   

4.
A single step photometric micromethod for determination of fatty acids in lipids in benzene solution, using rhodamine 6G reagent, has been developed. The method eliminates the disadvantage of formation of a biphasic system and is applicable in the presence of glycerides, sterols, epoxy compounds, hydrocarbons and long chain hydroxy compounds such as long chain fatty alcohols. The long chain fatty acids from C12 to C22, both saturated and unsaturated, can be determined with reasonable accuracy in the concentration range of 0.08–0.25 μmole/ml. The method is simple, rapid, and requires relatively inexpensive chemicals.  相似文献   

5.
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   

6.
The unsaponifiable lipids and total fatty acids of a nonphotosynthetic diatom,Nitzschia alba, have been examined. The major fatty acids were found to be 14∶0, 16∶0, 18∶1, and 20∶5; small amounts of 15∶0, 16∶1, 18∶0, 18∶2, 18∶3, and 20∶4 acids also were present. The unsaponifiable lipids consisted mostly of sterols, with only traces (<0.1%) of hydrocarbons (chiefly C16, C18, and C28 normal olefins). The sterols contained brassicasterol (major) and clionasterol (minor), as well as traces of an unidentified sterol; clionasterol was present only in glycosidically bound form.  相似文献   

7.
The lipid class compositions of adult Pacific oysters [Crassostrea gigas (Thunberg)] were examined using latroscan thin-layer chromatography/flame-ionization detection (TLC/FID), and fatty acid compositions determined by capillary gas chromatography and gas chromatography/mass spectrometry (GC/MS). The fatty acid methyl esters were separated using argentation TLC and also analyzed as their 4,4-dimethyloxazoline derivatives using GC/MS. Major esterified fatty acids inC. gigas were 16∶0, 20∶5n−3, and 22∶6n−3. C20 and C22 nonmethylene interrupted (NMI) fatty acids comprised 4.5 to 5.9% of the total fatty acids. The NMI trienoic fatty acid 22∶3(7,13,16) was also identified. Very little difference was found in the proportions of the various lipid classes, fatty acids or sterols between samples of adult oysters of two different sizes. However, significant differences in some of the lipid components were evident according to the method of sample preparation used prior to lipid extraction with solvents. Lyophilization (freeze drying) of samples led to a significant reduction in the amounts of triacylglycerols (TG) extracted by solvents in two separate experiments (7.0 and 52.5% extracted). Extracts from lyophilized samples had less 16∶0, C18 unsaturated fatty acids, and 24-ethylcholest-5-en-3β-ol, while C20 and C22 unsaturated fatty acids comprised a higher proportion of the total fatty acids. There was no significant change in the amounts of polar lipids, total sterols, free fatty acids or hydrocarbons observed in extracts from lyophilized samples relative to extracts from nonlyophilized samples. Addition of water to the freezedried samples prior to lipid extraction greatly improved lipid yields and resulted in most of the TG being extracted.  相似文献   

8.
Body lipids of P. sarana of four different sizes were fractionated into phospholipids, neutral lipids, nonsaponifiables, total fatty acids, polyunsaturated, monounsaturated and saturated fatty acid fractions. Percentage composition of each fraction was determined. The triglyceride fatty acids were identified by thin layer and gas liquid chromatography. C8 to C23 fatty acids including both odd numbered and branched chain acids were detected. The major constituents were C14, C15, C16, C16:1, C18 C18:1, C18:2, C18:3; forty-three other acids were detected in lower proportions. Composition of each fatty acids and their variation with size have been discussed.tP. sarana body lipids in general showed a behavior typical of fresh water fish by having a higher percentage of saturated C16 and unsaturated C18 acids and a lower percentage of unsaturated C20 acid.  相似文献   

9.
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   

10.
Sulfonated acrylate esters have been synthesized by using renewable raw materials such as fatty alcohols of Al‐Ceder oil. Mixed fatty acids were isolated from Al‐Ceder oil by hydrolysis; both saturated and unsaturated fatty acids were isolated from the mixed fatty acids. The methyl esters of mixed fatty acid, saturated and unsaturated acids of Al‐Cedre oil were subjected to reduction with (LiAlH4) to give the corresponding fatty alcohols. The products of the reduction process were saponified and the hydroxyl values were estimated to further confirm the reduction occurrence. The acrylate esters were synthesized by esterification of acrylic acid with fatty alcohols of C16:0, C18:0, C18:1, and C18:2 mixed saturated, mixed unsaturated and mixed fatty acids of Al‐Cedre oil, respectively. This esterification was followed by addition of NaHSO3 to form bisulfite adducts. The structures of the prepared surfactants were characterized by IR and 1HNMR spectroscopy. A series of useful surface parameters, stability towards acids and base hydrolysis and calcium stability have been determined.  相似文献   

11.
The non-water-soluble fraction of Carica papaya latex (CPL) constitutes a waste material from papain production; very little information exists regarding its chemical composition. The non-water-soluble fraction of CPL was fractionated by liquid chromatography into neutral lipids, glycolipids and phospholipids. The most abundant compounds were found to be the polar lipids, accounting for 79.2% (w/w) of the total extractible matter, while the total amount of neutral lipids was only around 20%. It was composed of free fatty acids, sterols and triterpenic alcohols, but no glycerides were detected. A high content of saturated fatty acids was measured; these saturated fatty acids were represented by very long chains with C24:0, C26:0 and C28:0 accounting for 6.3, 11.0 and 6.3%, respectively, in the total extractible matter and 7.3, 9.0 and 3.9% in the FFA fraction. The monounsaturated fatty acids were about 23–25% in both samples, with oleic acid (C18:1) being the most abundant. The polyunsaturated fatty acids that were 25.1% in the total matter and 21.6% in the FFA fraction were mainly represented by linoleic acid (C18:2n-6). Finally, a very interesting characteristic of the FA composition of this latex concerns the presence of odd-numbered fatty acids in significant amounts (around 22% in the total extract and 24.3% in the FFA fraction).  相似文献   

12.
Three groups of diesters have been isolated and identified in the lipids of steer meibomian glands. The first group, designated as α Type I, with the abbreviated formula FA-αOHFA-FA1c, consisted of α-hydroxy fatty acids esterified to fatty acids and fatty alcohols in the approximate molar ratio 1∶1∶1. The second group, designated as ω Type I-St, with the abbreviated formula FA-ωOHF A-St, consisted of ω-hydroxy fatty acids esterified to fatty acids and sterols in the approximate molar ratio 1∶1∶1. The third group, designated as α,ω Type II, with the abbreviated formula FA-α,ωdiol-FA, consisted of α,ω-diols esterified to 2 moles of fatty acids. The sum of the different diesters comprised about 9% of total steer meibomian lipids. Capillary GLC of the fatty acids of αType I diesters showed the fatty acids to be a family with a two-cluster profile, one at C12 to C20 and the other at C21 to C31, with anteiso chains predominating. Fatty acids from ωType I-St and α,ωType II diesters gave mainly a one-cluster profile in the short long chain, C23 to C30, with anteiso chains predominating, while the α-hydroxy fatty acids were short chain C13 to C18 acids with C16 predominating. The sterols in diesters ωType I-St were cholesterol (∼60%), Δ7 cholestenol (∼35%) and an unidentified compound (∼5%) with a GLC retention time slightly longer than Δ7 cholestenol on SE-30 phase. The ω-hydroxy fatty acids and α,ω-diols both were of exceedingly long chain lengths, C29−C38, and showed similar GLC profiles. Two types of triesters comprising approximately 1% of total steer meibomian lipids have been isolated but incompletely characterized. In terms of molar ratios, one group of triesters gave fatty acids:ω-hydroxy fatty acids:α-hydroxy fatty acids:sterols + fatty alcohols as approximately 1∶1∶1∶1. The other contained fatty acids, α-hydroxy fatty acids and α,ω-diols in what appears to be a complex mixture of several triesters. Diesters ωType I and α,ωType II also were found in human meibum. Hitherto these two diesters have not been found in any animal tissue.  相似文献   

13.
The first direct evidence is provided for the presence of unconventional lipids in a particular subcellular membrane system of a sponge. Spherulous cells were isolated from the variety of cell types present in the marine spongeAplysina fistularis by density gradient centrifugation. Spherulous cell plasma membrane was subsequently isolated by cell rupture followed by differential centrifugation and sucrose, or Percoll, density gradient ultracentrifugation. Plasma membrane isolates were identified and assessed for purity using [3H] concanavalin A plasma membrane marker, sodium dodecyl sulfate polyacrylamide gel electrophoresis and ratios of protein, sterol and phosphate. Plasma membrane isolates could not be assessed for purity by traditional enzymatic means. Spherulous cell plasma membrane was found to contain unusual lipids, including long-chain (C24–C30) fatty acids (16.8–27.2%) and unconventional 26-alkylated sterols (66.4–72.6%), in addition to more conventional fatty acids and sterols. Spherulous cell intracellular membranes were also found to contain long-chain fatty acids and unconventional sterols, although the relative importance of these unusual lipids apparently varies between intracellular membranes, with some containing approximately 50% long-chain acids. Part 19 of “Phospholipid Studies of Marine Organisms.” For Part 18 see Li, H., Duzgunes, N., Ayanoglu, E., and Djerassi, C.,Chem. Phys. Lipids, in press.  相似文献   

14.
K. Staphylakis  D. Gegiou 《Lipids》1985,20(11):723-728
Sterol lipids of cocoa butter (cocoa beansLome Tongo) were fractionated into free sterols, steryl esters (SE), steryl glucosides and acylated steryl glucosides (ASG). 4-Desmethyl, 4-methyl and 4,4′-dimethyl sterols or triterpene alcohols, which were isolated as free sterols or which resulted from hydrolysis, were determined by thin layer chromatography-flame ionization detection and identified by gas chromatography and combined gas chromatography-mass spectroscopy. Free sterols comprise the main sterol fraction in cocoa butter. Esterified sterols amount to 11.5% of total sterols and glucosidic sterols to 16.3%. Fatty acids and D-glucose from hydrolysis of esters and glucosides were analyzed. The fatty acids of SE and ASG are richer in unsaturated fatty acids than cocoa butter total fatty acids.  相似文献   

15.
B. F. Szuhaj  R. L. McCarl 《Lipids》1973,8(5):241-245
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   

16.
The fatty acid composition of the seed oil of 19 wild legume species from southern Spain was analyzed by gas chromatography. The main seed oil fatty acids ranged from C14:0 to C20:0. Among unsaturated fatty acids, the most abundant were linoleic, oleic and linolenic acids, except for Lathyrus angulatus, L. aphaca, L. clymenum, L. sphaericus and L. nigricans where C18:3 contents were higher than C18:1 contents. Palmitic acid was the most abundant saturated acid in studied species, ranging from 11.6% in Lathyrus sativus to 19.3% in Lens nigricans. All studied species showed higher amounts of total unsaturated fatty acids than saturated ones. Among studied species, the ω6/ω3 ratio was variable, ranging from 2.0% in L. nigricans to 13.8% in L. sativus, there being eight species in which the ω6/ω3 ratio was below 5. The fatty acids observed in these plants supports the use of these plants as a source of important dietary lipids.  相似文献   

17.
S. Ruggieri  A. Fallani 《Lipids》1979,14(4):323-333
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   

18.
Wax esters of secondary alcohols constitute 18–20% of the cuticular lipid extract ofMelanoplus packardii and 26–31% of the cuticular lipids ofMelanoplus sanguinipes. The total number of carbons in the wax esters range from 37–54 with 41 predominating in both species. The fatty acids ofM. packardii wax esters are 16∶0, 18∶0, 14∶0, 20∶0 and 12∶0 in decreasing quantity. The fatty acids ofM. sanguinipes wax esters are 18∶0, 20∶0, 16∶0 22∶0, 14∶0, 19∶0 and 17∶0 in decreasing quantity. The secondary alcohols from the wax esters ofM. packardii are C25, C23 and C27 in decreasing quantity, and the secondary alcohols of theM. sanguinipes are C23, C25, C21, C27, C24, C22 and C26 in decreasing quantity. Each secondary alcohol consists of two to four isomers with the hydroxyl group located near the center of the chain. Montana Agriculture Experiment Station, Journal Series No. 332.  相似文献   

19.
The seed oil of Pimpinella acuminata species of the family Umbelli-ferae was extracted with chloroform : methanol (2:1) for the separation of different classes of lipids as hydrocarbons (1.7%), sterol esters (traces), triglycerides (74.1%), free fatty acids (6.6%), 1,3-diglycerides (1.6%), 1,2-diglycerides (1.6%), sterols (1.8%), mono-glycerides (2.0%), phosphatidyl ethanolamine (0.8%), phosphatidyl choline (1.2 %), lyso phosphatidyl ethanolamine (0.4%), phosphatidyl inositol (1.2%) and unknown (7.0%). The fatty acids as determined by application of gas liquid chromatography is C10-C22, whereas C16:0, C18:0-C18:2 and C18:2 are predominantly present in all polar and non-polar lipid classes.  相似文献   

20.
We isolated two new microorganisms capable of converting vegetable oil to several rare unsaturated fatty acids and rare unsaturated fatty alcohols from a soil sample. The strains were identified as belonging to the same genus and species, Aeromonas hydrophila. The rare unsaturated fatty acids and rare unsaturated fatty alcohols were accumulated as a wax ester form by the strains. Compared to other strains, the A. hydrophila isolates effectively decreased fatty acid chain lengths and converted rapeseed oil, which is rich in 9-C18:1 fatty acid, into rare fatty acids, such as 7-C16:1 fatty acid and 5-C14:1 fatty acid. Furthermore, the A. hydrophila isolates converted the resulting fatty acids to rare unsaturated fatty alcohols, such as 7-C16:1 fatty alcohol and 5-C14:1 fatty alcohol. The isolates also converted safflower oil, which is rich in 9,12-C18:2 fatty acid, to 7,10-C16:2 fatty acid, 5,8-C14:2 fatty acid, 9,12-C18:2 fatty alcohol, 7,10-C16:2 fatty alcohol, and 5,8-C14:2 fatty alcohol. 7,10,13-C16:3 fatty acid, 9,12,15-C18:3 fatty alcohol, and 7,10,13-C16:3 fatty alcohol were also converted from linseed oil, which is rich in 9,12,15-C18:3 fatty acid, by the A. hydrophila isolates. These fatty acids and fatty alcohols are rarely found in natural oils. Since decreasing fatty acid carbon chain lengths from the carboxyl end and reducing unsaturated fatty acids to unsaturated fatty alcohols are both difficult reactions to accomplish by chemical means, we suggest that these A. hydrophila isolates may facilitate introduction of new bioprocess for producing rare unsaturated fatty acids and rare unsaturated fatty alcohols, especially fatty alcohols harboring more than two double bonds.  相似文献   

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