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1.
The fate of labeled palmitate, stearate, and acetate administered to the yellow clam,Mesodesma mactroides, was investigated. 1-14C palmitic and 1-14C stearic acids were oxidized to CO2 to a limited extent. They were mainly incorporated in diacylglycerols and triacylglycerols and were converted to higher homologs.
After administration, palmitic acid was converted to stearic and oleic acids, whereas administered stearic acid was converted
to 18∶1, 18∶2, 20∶1, and 20∶2 acids. Labeled acetate was readily included by the clam in 12∶0, 14∶0, 14∶1, 15∶0, 16∶1, 16∶1,
16∶2, 18∶2, 18∶1, 18∶2, 20∶1, 20∶2, and 20∶3 acids. 相似文献
2.
The fate of labeled linoleic, α-linolenic, and higher homologs of α-linolenic acid administered to the yellow clam,Mesodesma mactroides, was investigated. It was found that the clam incorporated the acids dissolved in sea water and converted 18∶2 (n−6) into
20∶2 (n−6) and 18∶3 (n−3) into 18∶4 (n−3) and 20∶3 (n−3). The addition of casein hydrolysate to the sea water increased the
desaturation capacity of the clam and allowed the conversion of 18∶2 (n−6) into 18∶3 (n−6) to be demonstrated. An enhanced
desaturation of 18∶3 (n−3) into 18∶4 (n−3) was also demonstrated. After 12 hr administration of the acid, no radioactivity
was found in arachidonic, 20∶5 (n−3), or 22∶6 (n−3). Feeding the clams a culture ofPhaeodactylum tricornutum previously incubated with 1-14C-α-linolenic acid demonstrated that all the homologs of the α-linolenic series were found in the clam without any important
changes. Six hour administration of labeled linolenic acid resulted in the incorporation of the acid into diglycerides and
phospholipids.
Member of the carrera del Investigador Cientifico of the Consejo Nacional de Investigaciones Cientificas y Tecnicas 相似文献
3.
The lipid composition of the yellow clam,Mesodesma mactroides, that lives in the northern beaches of the Buenos Aires province of Argentina was studied. The main nonpolar lipids are triglycerides
and alkoxyglycerides. Phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl serine are the main phospholipids.
The predominant fatty acids are 16∶0, 16∶1ω7, 18∶0, 18∶1ω9, 20∶5ω3, and 22∶6ω3. The are mainly provided by the clam's food
and stored in the hepatopancreas. The content of polyunsaturated acids increases in summer together with an increase in nonpolar
lipids and is correlative with an increase in phytoplankton in the sea water. Sexual maturity modifies the lipid composition
of gametes. 相似文献
4.
E. Klenk 《Journal of the American Oil Chemists' Society》1965,42(7):580-582
Feeding experiments with C14-labeled and unlabeled unsaturated fatty acids have been used to study the possible routes of formation of the C20- and C22-polyenoic fatty acids of rat liver phosphatides. The acids of the palmitoleate, oleate, linoleate, and linolenate types (considered
on the basis of the position of the double bond closest to the methyl end) are apparently formed from the C16 and C18 unsaturated acids of the corresponding types. The results rule out possible transformations of the C20- and C22-polyenoic acids from one type to another, and demonstrate the exclusive introduction of new double bonds toward the carboxyl
group. Isomers of linoleate or linolenate in which the double bonds were shifted by one carbon atom toward the carboxyl or
methyl groups were incorporated into the phosphatides only to a negligible extent in the form of polyenoic acids. 相似文献
5.
A. Gangadhar R. Subbarao G. Lakshminarayana 《Journal of the American Oil Chemists' Society》1984,61(7):1239-1241
Hydroxylamine has been recently found to react with ethyl acetate to generate diimide in situ. This reaction was used to reduce
10-undecenoic, oleic, linoleic, stearolic, concentrates of ricinoleic, cyclopentene and cyclopropene fatty acids (FA), dehydrated
castor oil FA, 10-undecen-1-ol, oleyl alcohol and castor fatty alcohols. Unsaturated FA and their corresponding alcohols reacted
in a similar manner. Terminally unsaturated, cyclopropene and cyclopentene FA were more reactive than oleic acid, which, in
turn, was more reactive than hydroxymonoenoic acids. Conjugated dienoic FA reduced faster than nonconjugated dienoic acids.
Partial hydrogenation using this reagent is particularly advantageous in determining geometry and the position of double bonds
in the polyunsaturated FA, as it can be carried out in the absence of oxygen or oxidizing agents unlike hydrazine reductions. 相似文献
6.
7.
J. P. Friedrich E. W. Bell L. E. Gast 《Journal of the American Oil Chemists' Society》1965,42(7):643-645
A series of 16 esters of C18-saturated cyclic acids (HCal) were prepared, and partial evaluation showed that several have qualities that recommend them
as potential low-temp lubricants. Starting materials used were primary, straight, and branched chain alcohols C4–C7; perfluoro alcohols; phenol; cyclohexanol; and C18-saturated cyclic alcohols prepared from cyclic acids. Viscosities were measured at −40, 100, and 210F. Their viscosity indexes
ranged from 26 to 143. Pour points or melting points of the esters ranged from −27 to −96F. The oxidative stability of these
esters measured at 347F according to a modification of the test method for military specification MIL-L-7808 was in nearly
all cases equal or superior to the control bis-2-ethylhexyl sebacate. More severe oxidation tests showed the esters of HCal
to be slower than the control in the development of acidic decomposition products.
Presented at AOCS meeting, New Orleans, La., April 1964.
A laboratory of the No. Utiliz. Res. and Dev. Div., ARS, USDA. 相似文献
8.
Tetraselmis suecica andDunaliella tertiolecta were grown for 24 hr in the presence of14C sodium bicarbonate and then fed separately to batches of juvenile oysters,Crassostrea gigas, for 3 days.D. tertiolecta contained fatty acids no longer than C18; 22∶6ω3 was absent inT. suecica. Analysis of the oyster fatty acids by radio gas chromatography (GC) showed that oysters were able to incorporate some of
the dietary14C label into long-chain fatty acids not supplied in the diet, e.g., C20 and C22 mono- and polyunsaturated fatty acids, and particularly 20∶5ω3. However, the low14C incorporation into fatty acids longer or more unsaturated than those supplied in the diet suggests that elongation and desaturation
activity in young oysters is not sufficient to sustain optimum growth. 相似文献
9.
The low incidence of cardiovascular disease associated epidemiologically with high consumption of food rich in n-3 fatty acids suggests the possibility that part of the beneficial cardiovascular effects of these natural substances may be due to a reduction of atherosclerosis. This has been recently confirmed in autoptic data and in at least one prospective trial evaluating the progression of coronary atherosclerosis in humans. This paper reviews published literature on n-3 fatty acids and atherosclerosis in animal models and in humans and in vitro experimental data yielding suport to the hypothesis of antiatherosclerotic effects of these substances. 相似文献
10.
Suspension cultures of finely divided soybean cells established from callus were incubated with sodium [1(14)C] acetate for periods up to 86 hr. Lipids and fatty acids were analyzed for radioactivity in samples harvested at logarithmic time periods. Incorporation of acetate into cell lipid was directly proportional to the logarithm of time up to 32 hr, after an initial lag of 4-6 hr. Most of the lipid radioactivity was found in the phospholipid fraction, and all common soybean fatty acids became labeled within 6 hr. The order of labeling and distribution of radioactivity with time were essentially the same as in tissues from intact growing plants. These results support the concept of sequential desaturation of oleic acid in the cells. It was concluded that valid studies of the biosynthesis of common lipids in the soybean can be carried out for extended periods of time by use of undifferentiated cells in suspension cultures. 相似文献
11.
Monoalkyl esters of linseed-oil-derived C18-saturated cyclic acids (HCal), described in earlier work, showed promise as lubricant base stocks for turbine aircraft as
set forth in the military specification MIL-L-7808E. These esters, however, did not exhibit the increased oxidative stability
and higher viscosity required by the more recent specification MIL-L-23699.
Six diol esters of HCal have now been prepared. Both hindered and unhindered dihydric alcohols were used, including ethylene
glycol, 1,4-cyclohexanedimethanol, 1,4-benzenedimethanol, 2,3-dimethyl-1,3-propanediol and 2,2,4,4-tetramethyl-1,3-cyclobutanediol
(I). The viscosities of these esters at 210F ranged from 10.1 to 19.6 centistokes and the pour points, from −35 to −62F. Oxidative
stabilities at 400F were determined with 0.5% each of phenyl-a-napthylamine (PANA) andp,p’-dioctyldiphenylamine as inhibitors. The esters of the unhindered diols had poor stability, whereas esters of the hindered
diols, in particular I, exhibited excellent resistance to the formation of acidic decomposition products and sludge. Although
the HCal ester of I by itself is too viscous to meet specification MIL-L-23699, its ASTM slope (0.650) is excellent. Blends
of this material with less viscous hindered esters, commercially available, may find application as lubricants for high-performance
turbine engines used in various aircraft.
Presented at the AOCS Meeting in Los Angeles, 1966.
No. Utiliz. Res. Dev. Div., ARS, USDA. 相似文献
12.
Uptake and metabolism of fatty acids by Soybean suspension cells 总被引:1,自引:0,他引:1
Soybean suspension cultures very rapidly take up C16 and C18 fatty acids by a nonspecific, nonenzymic binding of exogeneously added fatty acids to cell walls and by a subsequent transfer
into the cell where they are rapidly incorporated into triacylglycerols, phosphatidylcholines, and phosphatidylethanolamines.14C-Palmitic and14C-stearic acids follow this sequence but are not desaturated, wherease14C-oleic and14C-linoleic acids are transferred more rapidly than the saturated fatty acids and are then further modified. All the data fit
a sequence of events by which free oleic acid is first activated to a CoA thioester, and then desaturated to linoleyl-CoA;
both thioesters are then transferred to triacylglycerols, phosphatidylcholine, and phosphatidylethanolamine. 相似文献
13.
Ryota Hosomi Kenji Fukunaga Hirofumi Arai Seiji Kanda Toshimasa Nishiyama Teruyuki Kanada Munehiro Yoshida 《European Journal of Lipid Science and Technology》2010,112(5):537-544
It has been demonstrated that the amount and type of dietary fat are factors involved in the risk of arteriosclerosis and coronary or cerebral artery disease through lipid metabolism. In this study, we investigated the effects of phospholipids (PLs) containing n‐3PUFAs on lipid metabolism in rats. PLs containing n‐3PUFAs were prepared from squid (Todarodes pacificus) mantle muscle. Groups of male Wistar rats were fed AIN93G diet containing soybean oil (SO, 7%), fish oil (1.2%) + SO (5.8%), soybean PLs (1.8%) + SO (5.2%), or PLs containing n‐3PUFAs (1.8%) + SO (5.2%). The following indicators were assayed as indexes of lipid metabolism: TAG and cholesterol in serum and liver, fecal cholesterol, bile‐acid excretion, and liver mRNA expression levels of genes encoding proteins involved in cholesterol homeostasis. Serum and liver TAG contents decreased significantly in the group fed PLs containing n‐3PUFAs as compared to other groups, accompanied by a significant decline in the expression level of sterol regulatory element binding protein‐1c. The decrease in cholesterol content in the group fed PLs containing n‐3PUFAs was due to the increase in fecal cholesterol excretion and the increase of mRNA expression levels of ATP‐binding cassette (ABC) G5 and ABCG8 in liver. Practical applications : PLs containing n‐3PUFAs decreased serum and liver TAG contents compared with that induced by soybean PLs. Further, PLs containing n‐3PUFAs can induce a reduction in serum and liver cholesterol concentrations as well as the triglyceride‐reducing effect of conventional n‐3PUFAs containing TAG. In other words, dietary n‐3PUFAs contained in PLs can prevent life‐style diseases such as hyperlipidemia, arteriosclerosis and coronary, or cerebral artery disease more effectively than TAG containing n‐3PUFAs. Therefore, it is expected that the risk of lifestyle diseases would be decreased if PL containing n‐3PUFAs can be supplied routinely. In this study, PLs containing n‐3PUFAs were prepared from squid mantle muscle. On an industrial scale, such PLs can be produced from various unused resources and waste materials of fisheries. We conclude that highly functional foods could be developed based on the findings of this study, and would be available for health promotion worldwide. 相似文献
14.
15.
The growth of female rats was depressed further by the incorporation of DDT into a ration deficient in essential fatty acids
(EFA). With female rats fed a ration supplemented with EFA, DDT produced a slight stimulation in growth. DDT also produced
an increase in the 20∶3ω9/20∶4ω6 ratio in liver lipids of male rats fed a ration deficient in EFA. These data indicate an
effect in EFA nutrition. Substantial changes in the fatty acid composition of liver lipids resulted from the feeding of DDT.
The proportion of 16∶0 was decreased, while that of 18∶0 was increased. With rats on the supplemented rations an increase
in the proportion of 20∶4ω6 was observed, while in the deficient rats a comparable increase was observed in the proportion
of 20∶3ω9. These changes in fatty acid composition have been related to the proliferation of hepatic smooth endoplasmic reticulum
induced by the DDT, and it is suggested that this effect could increase the demand for EFA by the liver, thus influencing
EFA nutrition.
Technical Paper No. 3156, Oregon Agricultural Experiment Station. 相似文献
16.
Role of oleic acid in the metabolism of essential fatty acids 总被引:1,自引:0,他引:1
Groups of young male guinea pigs were fed diets containing corn oil, coconut oil, coconut oil plus elaidic acid, and coconut
oil plus oleic acid. The oleic acid-fed group showed signs of essential fatty acid deficiency after four weeks and severe
signs after eight weeks. The elaidic acid-fed group did not show these symptoms. It is proposed that oleic acid competes competitively
with linoleic acid as a substrate for the enzymes involved in linoleate transformations when only a very limited supply of
linoleic acid is available to the animals and oleic acid is made available in relatively large amounts.
A detailed analysis of the serum, liver, and adipose tissue lipid and a study of the incorporation of acetate-1-C14 into different lipids is presented.
This paper is based on work supported in part by United States Public Health Grant No. HTS 5306 and by a grant from the Nutrition
Foundation Inc., New York. 相似文献
17.
Cell free preparations of avocado mesocarp and spinach leaf tissue rapidly convert lauryl CoA to DL-3-hydroxyl lauric acid as well as 2-, and 3-dodecanoic acids. The conversion does not occur under anaerobic conditions unless a suitable redox carrier such as ferredoxin is present. H2 18O is incorporated into the 3-hydroxyl function, but O2(18) is not. The characteristics of this system are presented and a possible function of this system is proposed. 相似文献
18.
Summary Fatty acid esters modified with epoxy or acetoxy groups were found to be compatible with polyvinyl acetate. These esters are
good plasticizers for polyvinyl acetate compositions and may be used for plasticizing polyvinyl acetate in latex form. The
use of a good swelling agent, such as toluene, was found desirable for permitting plasticization of these emulsions. The epoxidized
oils may also assist in reducing container corrosion and in stabilizing the emulsions by reacting with the acetic acid formed
by the hydrolysis of residual vinyl acetate.
Emulsions of copolymers of vinyl acetate and vinyl epoxystearate were prepared, yielding clear, hard films which were internally
plasticized. The epoxy group in these interpolymers is a potential source for cross-linking vinyl acetate polymer films. The
epoxy group of the co-polymers (internal-phase stabilization) and the epoxidized oils (external-phase stabilization) were
found to be virtually equivalent for removal of acetic acid from polyvinyl acetate emulsions.
Presented at the Fall Meeting, American Oil Chemists' Society, Philadelphia, Pa., October 11, 1955.
A laboratory of the Eastern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture. 相似文献
19.
Joseph Mirallès Gilles Barnathan Renée Galonnier Thioro Sall Abdoulaye Samb Emile Marcel Gaydou Jean-Michel Kornprobst 《Lipids》1995,30(5):459-466
Fatty acids from total lipids of the gorgonianLeptogorgia piccola (white and yellow morphs), collected from the same area at two different periods with regard to the average water temperature,
were studied. More than fifty fatty acids were identified as methyl esters andN-acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. Three new, branched-chain unsaturated fatty
acids were identified in addition to the unusual 7-methyl-6-hexadecenoic acid, namely 10-methyl-6-hexadecenoic, 7,9-dimethyl-6-hexadecenoic,
and 10-methyl-6,9-heptadecadienoic acids. Also 6,9-heptadecadienoic acid was identified. The fatty acid patterns of specimens
harvested in colder waters were quite different from those harvested in warmer waters in that the former contained high amounts
of methylene-interrupted polyunsaturated acids, including tetracosapolyenoic acids, especially 6,9,12,15,18–24∶5 (up to 15.8%
of the total acid mixture) and 6,9,12,15,18,21–24∶6 (up to 5.3%). Arachidonic acid was, nevertheless, a major component in
all the fatty acid mixtures studied (13.6–20.5%). Based on gas chromatography/Fourier transform infrared experiments, the
double bonds were assigned the (Z) configuration. Several fatty aldehydes and their dimethyl acetals were also detected, of which the most abundant was octadecanal. 相似文献
20.
Erik Berg Schmidt Jeppe Hagstrup Christensen Inge Aardestrup Trine Madsen Sam Riahi Vibeke Ellegaard Hansen Helle Aarup Skou 《Lipids》2001,36(1):S65-S68
There is some evidence from epidemiology that intake of n-3 polyunsaturated fatty acids (PUFA) from seafood may protect against coronary artery disease (CAD). This hypothesis is further supported from animal data showing a beneficial effect of n-3 PUFA on thrombosis and atherosclerosis in animals fed fish oils in most, but not all, studies. There are several mechanisms by which an increased intake of marine n-3 PUFA may protect against CAD; the most universal finding is a reduction of plasma triglycerides. It is puzzling, however, that a very low amount of n-3 PUFA, with no known beneficial biochemical effects, seems to be cardioprotective. It has therefore been of paramount interest to perform clinical trials. Such evidence and trials are discussed in later chapters, and the results have been very encouraging. 相似文献