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1.
2.
Effects of the ratio of polyunsaturated and monounsaturated fatty acid to saturated fatty acid on rat plasma and liver lipid concentrations 总被引:6,自引:0,他引:6
The effects of dietary monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid+MUFA/saturated fatty acid (PUFA+MUFA/SFA)
ratio on plasma and liver lipid concentrations were studied. In experiment I, when rats were fed with 40% fat (energy%, PUFA/SFA
ratio 1.0) and 1% (w/w) cholesterol (C) diets for 21 d, a large amount of MUFA (28.1 energy%, PUFA+MUFA/SFA=5.7) in the diet
was found to increase the plasma total C, triacylglycerol (TAG), and phospholipid (PL) as compared with the low-MUFA diet
(7.0 energy%, PUFA+MUFA/SFA=1.4). The plasma very low density lipoprotein (VLDL)-C, VLDL-TAG, VLDL-PL, and low density lipoprotein
(LDL)-C increased significantly in the high-MUFA diet group, but high density lipoprotein (HDL)-C did not change significantly.
The high-MUFA diet resulted in greater accumulation of liver C but lesser accumulation of TAG. In experiment II, when dietary
SFA was fixed at a certain level (13.2 energy%; PUFA+MUFA/SFA=2.0), rats given a larger amount of MUFA (23.1 energy%; PUFA/MUFA=0.2;
MUFA/SFA=1.8) showed higher plasma and liver C levels than did the low-MUFA diet (7.7 energy%; PUFA/MUFA=2.5; MUFA/SFA=0.6).
When PUFA was fixed at a certain level (24.4 energy%), there was not a significant difference in the plasma C level between
the high-and low-MUFA dietary groups (PUFA+MUFA/SFA=4.8 and 8.4), but the higher PUFA+MUFA/SFA diet, which was high in MUFA/SFA
ratio, significantly decreased the plasma HDL-C and TAG levels. However, when MUFA content was fixed at a certain level (16.4
energy%), no significant difference was observed between the two groups with different PUFA/SFA ratios of 0.2 and 4.1, but
liver C level was raised in the higher PUFA/SFA diet. It appears that the PUFA/SFA ratio alone is unsuitable to predict the
change of plasma C level, because a large amount of dietary MUFA may lead to an increase of plasma and liver lipids in rats.
It seems that the prerequisites for keeping low plasma and liver C are (i) low MUFA/SFA ratio, (ii) high PUFA/MUFA ratio,
and (iii) PUFA+MUFA/SFA ratio not to exceed 2. 相似文献
3.
Y. Sita Rama Sastry Gollamudi Lakshminarayana 《Journal of the American Oil Chemists' Society》1971,48(9):452-454
Chlorophyll-sensitized peroxidation of methyl laurate and methyl stearate was carried out at 30–40 C under intermittent exposure
to light from a 500 w tungsten bulb. Hydroperoxides were isolated by solvent partition, reduced to hydroxy esters and purified
by silicic acid column chromatography and preparative thin layer chromatography (TLC). Gas liquid chromatography, TLC, IR
spectrophotometry, NMR and mass spectroscopy of the hydroxy esters showed that the oxygen attack was exclusively on the α-methylenic
carbon atom.
One of 28 papers presented at the Symposium, “Metal-Catalyzed Lipid Oxidation,” ISF-AOCS World Congress, Chicago, September
1970. 相似文献
4.
Primary cultures of newborn rat cardiomyocytes were grown in medium supplemented with cyclic fatty acid monomers (CFAM) which
had been isolated from heated linseed oil. The cells were harvested, and lipids were extracted and fractionated using silica
cartridges and high-performance liquid chromatography. The CFAM structures isolated from cellular lipids were determined and
compared to those that had been supplemented to the medium, using gas-liquid chromatography coupled with mass spectrometry
(GC/MS). We found that CFAM were incorporated into phospholipids and neutral lipids of cardiomyocytes. Furthermore, CFAM with
a cyclopentyl ring structure were more abundant in cardiomyocytes than were the cyclohexyl ring isomers. Our data suggest
that CFAM of the 5-carbon and 6-carbon ring series are metabolized differently in newborn rat cardimyocytes. 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.
D. A. Wolfe P. Venkata Rao D. G. Cornwell 《Journal of the American Oil Chemists' Society》1965,42(7):633-637
The fatty acid composition of carcass and exoskeleton lipids was determined for the freshwater crayfishOrconectes rusticus. Lipid fractions were isolated by column and thin-layer chromatography. Fatty acid methyl esters and alcohol acetates were
then prepared and analyzed by gas-liquid chromatography. Peak identities were established from retention time data for methyl
esters, hydrogenated methyl esters, and saturated, monoene, diene, and polyene methyl esters separated as acetoxy-mercuri-methoxy
derivatives. Minor component acids were estimated from their relative compositions in these fractions.
Presented at the symposium honoring J. B. Brown, AOCS meeting in Chicago, 1964. 相似文献
7.
Cilia from the tunicateCiona intestinalis have been analyzed for, their biochemical compositions. Cholestanol is found to be a major steroidal component, whereas the
phospholipids are composed mainly of C14−C18 saturated fatty acids. The saturated nature of the lipids may be related to specific requirements of the ciliary membrane. 相似文献
8.
R. G. Ackman 《Journal of the American Oil Chemists' Society》1966,43(6):385-389
From data obtained in this laboratory two empirical formulas have been developed which correlate polyunsaturated fatty acids
indicated by GLC analyses with iodine values of marine oils or their fatty acid methyl esters. These formulas have been applied
to data from the literature with good agreement. It is suggested that these formulas function only with fats having the basic
composition of marine lipids, which consist principally of saturated, monounsaturated and very highly unsaturated fatty acids.
The presence of modest amounts of dienoic and trienoic fatty acids such as are found in freshwater aquatic life and in land
animals makes the formulas inapplicable, suggesting their use to distinguish marine fish oils and lipids from other types.
The formulas could be particularly useful in technological applications of marine oils where a rapid and approximate knowledge
of amount of polyunsaturated fatty acids is desirable. 相似文献
9.
Enzymatic synthesis of structured lipids from single cell oil of high docosahexaenoic acid content 总被引:1,自引:0,他引:1
Yugo Iwasaki Jeong Jun Han Miho Narita Roxana Rosu Tsuneo Yamane 《Journal of the American Oil Chemists' Society》1999,76(5):563-569
The lipase-catalyzed acidolysis of a single-cell oil (SCO) containing docosahexaenoic acid (DHA) and docosapentaenoic acid
(DPA) with caprylic acid (CA) was investigated. The targeted products were structured lipids containing CA residues at the
sn-1 and -3 positions and a DHA or DPA residue at the sn-2 position of glycerol. Rhizomucor miehei lipase (RML) and Pseudomonas sp. KWI-56 lipase (PSL) were used as the biocatalysts. When PSL was used > 60 mol% of total SCO fatty acids (FA) were exchanged
with CA, with DHA and DPA as well as the other saturated FA being exchanged. The content of the triacylglycerols (TG) containing
two CA and one DHA or DPA (number of carbon atoms = 41, i.e., C41) residue was high (36%), and the isomer with the desired configuration (unsaturated FA residue at the sn-2 position) represented 77–78% of C41. In the case of RML, CA content reached only 23 mol% in the TG. A large amount of DHA and DPA residues remained unexchanged
with RML, so that the resulting oil was rich in TG species containing two or three DHA or DPA residues (46%). TG C41 amounted to 22%, almost all of which had the desired configuration. This result suggested that the difference in the degree
of acidolysis by the two enzymes was due to their different selectivity toward DHA and DPA, as well as the difference in their
positional specificities. 相似文献
10.
A method was developed for the rapid determination of the initial velocity of the desaturation of saturated fatty acids. In
the reaction, DPNH was a more efficient electron donor than TPNH. Fatdeficient rats have a 2.5-fold greater level of acyl
desaturase per milligram of liver microsomal protein than did animals fed lab chow. Increasing the chain length of the acyl
substrate from 10∶0 to 18∶0 increases the rate of monoene formation, but 19∶0 is desaturated at a rate lower than that for
15∶0. The energy of activation (Ea) for the overall desaturation reaction has been determined for 12∶0 through 19∶0. The Ea
values for desaturation of 13∶0 and 16∶0 are markedly lowr than for the other acids. An interaction between the alkyl chain
of the substrate and polyunsaturated acids of the microsomal membrane-bound phospholipids is postulated to explain the recurring
3-carbon pattern of the relative reaction rates of the various acyl substrates. 相似文献
11.
K. K. Carroll 《Journal of the American Oil Chemists' Society》1965,42(6):516-528
Some characteristics of the fatty acid composition of animal tissue lipids are described and the origins of tissue fatty acids
are discussed briefly. The effect of dietary fat on composition of tissue lipids is discussed. Types of dietary fatty acids
for which experimental work is described include polyunsaturated fatty acids, short-chain fatty acids, fatty acids with chain
length greater than C18,trans unsaturated fatty acids, fatty acids with conjugated double bonds, acetylenic fatty acids, branched-chain fatty acids and
oxygenated fatty acids. The individuality of fatty acids is discussed in relation to their roles as components of tissue lipids. 相似文献
12.
Pregnant rats were fed a high carbohydrate diet containing either 1% trilinolein or 1% trilinolein with 0.2% methyl sterculate
from 18 day gestation to 21 day postpartum. The pups were weaned at 21 days and continued on the same diet for an additional
10 days. The microsomal stearyl CoA desaturase activities of the liver were effectively inhibited. Liver triglycerides showed
increases in the saturated fatty acids concentrations at the expense of the corresponding monoenes. The concentration ofcis 6–7 octadecenoic acid was elevated. In liver phospholipids, the concentration of stearic acid was increased without a corresponding
decrease in the oleic acid content. A drastic decrease in the nervonic acid (24∶1, n−9) concentration of liver sphingomyelin
was observed. The lipids of the brain did not contain sterculic acid, and brain desaturase activity was unaffected. There
was no significant change in the concentration of monoenoic acids from 16∶1 to 22∶1. However, nervonic acid was decreased
by 32%. These results suggest that brain nervonic acid may be derived from a precursor other than oleic acid. 相似文献
13.
Rat peri-renal and epididymal pre-adipocytes in culture undergoing triglyceride (TG) accumulation were incubated with oleic
(18∶1), linoleic (18∶2), α-linolenic (18∶3ω3), arachidonic (20∶4) and 4,7,10,13,16,19-docasahexaenoic (22∶6ω3) acids in the
presence of 0.8 μM insulin. The fatty acids were incorporated in cellular TG with relative enrichments over control from 1.4-fold
for 18∶1 to greater than 40-fold for 18∶3ω3. Greater than 80% of fatty acids taken up were incorporated into cellular TG.
The balance was distributed, in decreasing amounts, into phospholipids, unidentified intracellular constituents, and ketone
bodies. The P/S ratio of cellular TG was at least an order of magnitude lower than that of the external milieu for both cell
types and for all treatment groups, including controls. Doubling the concentration of treatment fatty acid increased its incorporation
into cellular TG. However, it did not affect the accumulation of the other fatty acids in TG. Epididymal cells consistently
acquire a higher proportion of treatment fatty acids in cell TG than peri-renal cells. Pre-adipocytes with polyunsaturated
fatty acids (PUFA)-enriched TG is a potential model for the study of PUFA metabolism in these types of cells 相似文献
14.
Analyses of the fatty acid content and composition of various lung lipids were conducted in rats 1 day, 5 days, and 12 days
after birth and in adult animals in order to define more clearly the specific lipid peroxidizing system found in neonatal
rat lungs. Lipid peroxidation occurs in the 900×g supernatant fraction of rat lung homogenates in an age-dependent manner
independent of the addition of any factor and is maximal at 5 days of age. No lipid peroxidation is evident in similar preparations
of either newborn or adult lung tissue. As the animals develop, arachidonic and docosahexaenoic acids, fatty acids which are
both highly susceptible to lipid peroxidation in the presence of a suitable catalyst, decrease gradually when measured as
the percentage of the total fatty acids in the triglyceride fraction of the lung. The total quantity of triglycerides, however,
is significantly lower in lungs from 1-day-old rats than at any other age. The fatty acid composition and total quantity of
both lung phospholipids and lung free fatty acids do not show similar changes. Following in vitro incubation of the 900×g
supernatant fraction of peroxidizing lung homogenates, an appreciable decrease in the amount of arachidonic and docosa-hexaenoic
acid could be detected in lung triglycerides. Less extensive decreases were observed in the phospholipid fraction. No changes
in these components were observed in newborn or adult animals. The addition of triarachidonin to the 900×g supernatant fraction
of lung homogenates resulted in increased malondialdehyde release at all ages tested while added arachidonic acid increased
the formation of malondialdehyde only in 5- and 12-day-old rat lung preparations. The addition of triolein, cholesterol arachidonate,
and diarachidonyl phosphatidylcholine had no effect on malondialdehyde formation at any age. The age-dependent lipid peroxidation
observed after in vitro incubation of rat lung homogenate preparations, therefore, may result from the relatively high concentration
of triglycerides containing polyunsaturated fatty acids present in the neonatal tissue. As the susceptible polyunsaturated
fatty acids of lung triglycerides are replaced by less unsaturated species, this activity may diminish concomitantly.
Recipient of Public Heath Service Research Career Development Award 5-K04-HD00068 from the National Institute of Child Health
and Human Development. 相似文献
15.
An examination of the suitability of an alkalimetric method for the determination of free fatty acid (FFA) contents in fats,
oils, and lipid extracts was conducted by comparing AOCS method Ca 5a-40 with a method based on a Chromarod-latroscan thin-layer
chromatography-flame-ionization detector (TLC-FID) system. The FFA contents determined by the alkalimetric method were consistently
higher than the genuine FFA contents obtained by the latroscan TLC-FID method. Phospholipids were found to be the major components
that contributed to the alkali-titratable, nongenuine FFA in the total FFA determined alkalimetrically. Contributions from
other polar lipid components were smaller, but they dominated as the proportion of phospholipids fell. The other alkali-titratable
polar components may include oxidized lipids and their by-products bound to protein fragments. The accurate determination
of FFA contents by alkalimetric methods may only be applicable to those commercially refined fats and oils that contain negligible
amounts of phospholipids. Corrections for the alkalimetrically determined FFA contents should be made for those fats and oils
with relatively high phospholipid contents by correlating the nongenuine FFA contents and the phospholipid contents. 相似文献
16.
High affinity receptors for fatty acid were purified from rat cardiac sarcolemmal membrane using gel filtration, DEAE-cellulose
chromatography and affinity chromatography. The purified protein was homogeneous on polyacrylamide gel electrophoresis with
the molecular weight of 60 kDa. Binding studies revealed the presence of a single class of high affinity binding sites with
an apparent dissociation constant of 1.0 μM and a maximal binding capacity of 12.1 pmol/μg protein. 相似文献
17.
It was found that carbon chain length of fatty acids strongly affects polymorphic selection in the cooling crystallization of glycine from water/saturated fatty acid emulsions. Two-dimensional packing density of saturated fatty acid head groups, which is inversely proportional to the number of carbon atoms, was shown to be responsible for polymorphic selection of glycine: γ-glycine was obtained from the emulsions of hexanoic acid and octanoic acid, whereas α-glycine was found to crystallize from the emulsions of dodecanoic acid, tetradecanoic acid, hexadecanoic acid and octadecanoic acid. Those results indicate that molecular structure of γ-glycine is only well matched with molecular structure of head groups of hexanoic acid and octanoic acid at the interface of the emulsion, and thus such molecular interface provides the preferential site for the organization of γ-form crystal structure from the liquid-like cluster of glycine. 相似文献
18.
Veerle De Graef Jeroen Vereecken Kevin W. Smith Krish Bhaggan Koen Dewettinck 《European Journal of Lipid Science and Technology》2012,114(5):592-601
TAGs play an important role in determining the functional properties of fat‐based food products such as margarines, chocolate, and spreads. Nowadays, special attention is given to the role of the TAG structure and how it affects functional properties such as mouth feel, texture, and plasticity. Key to this research is the need to develop more healthy fats with a reduced level of trans and saturated fatty acids (SFAs), while maintaining the desired properties. In this study, fat blends with identical levels of SFA (50%) but differing in the ratio asymmetric/symmetric blends were evaluated by pulsed NMR and texturometry as a function of storage time and storage temperature. A higher trisaturated TAG content gave rise to a higher solid fat content (SFC) at higher temperature and a lower SFC at lower temperature for both palmitic and stearic based blends. On the other hand, the effect of symmetry on the SFC‐profile of the blends was only clear for the stearic based blends. At lower temperatures, the SFC of symmetric TAG based blend (blend SM) was markedly lower than that of asymmetric TAG based blend (blend iS). However, from 30°C onwards, the SFC of blend SM was clearly higher than that of blend iS. The microscopic analyses revealed a denser crystal network for a higher degree of trisaturated TAG and for symmetric stearic based blends. Moreover, some blends showed a clear evolution of the microstructure during storage with smaller crystals transforming into larger ones. Finally, texture analyses demonstrated the importance of the crystallization and storage temperature on the hardness of the blends. 相似文献
19.
The changes occurring in the fatty acid composition of the erythrocyte lipids during the first weeks of life were studied
in the rat. The major changes consisted of a progressive decrease in oleic acid and a progressive increase in linoleic acid.
A lower but significant increase in arachidonic acid was also observed. These changes are not related to variations in erythrocyte
age; rather, they appear to be related to the age of the animal. Since somewhat similar changes were observed in the fatty
acid composition of the major lipid classes of plasma during the first weeks of life, the possibility that these variations
could account for the changes in the fatty acid composition of erythrocyte lipids was considered. Some support to this possibility
was found in the results of experiments in which erythrocytes taken from 15-day-old rats were incubated with plasma taken
from newborn rats. The changes in the fatty acid composition of erythrocytes and plasma lipids do not appear to be dependent
on dietary lipids, since they occur during the suckling period, i.e., before the rats begin to ingest the pelleted diet which
presents a fatty acid pattern completely different to that of the dams' milk. 相似文献
20.
Tomohito Hamazaki Masaharu Urakaze Masahiro Makuta Akio Ozawa Yasuji Soda Hiroshi Tatsumi Saburo Yano Akira Kumagai 《Lipids》1987,22(12):994-998
The ethyl ester of eicosapentaenoic acid (EPA) is the only pure EPA-containing lipid available in bulk for oral administration.
However, there is doubt as to whether EPA ethyl ester can efficiently increase the plasma levels of EPA in comparison with
the ability of other kinds of EPA-containing lipids to do so. Therefore, two other kinds of EPA-containing lipids were prepared
to study the efficiency of oral administration of those lipids for increasing the EPA content in plasma phospholipids and
cholesteryl esters. EPA-containing lipids which were investigated were [A], 1,2,3-trieicosapentaenoyl-glycerol, [B] 2-eicosapentaenoyl-phosphatidylcholine
and [C] ethyl ester of EPA. An adjusted amount of lipids [A], [B] and [C] was administered to rats through a gastric tube
for 4 days (the first experiment) or for 10 days (the second experiment), and the fatty acid composition of plasma phospholipids
and cholesteryl esters was determined. In the first experiment, there were no significant differences in the efficiency for
increasing EPA levels in either phospholipids or cholesteryl esters among the lipids. In the second experiment, the EPA levels
of both plasma phospholipids and cholesteryl esters of rats administered ethyl ester of EPA were significantly higher than
those of rats administered 2-eicosapentaenoyl-phosphatidylcholine. The EPA levels of the rats administered 1,2,3-trieicosapentaenoylglycerol
were between the levels of the two groups mentioned above, but the differences in the EPA levels were not significant. Although
an ethyl ester-type molecule is not a naturally occurring lipid, ethyl ester of EPA is equal to 1,2,3-trieicosapentaenoyl-glycerol
and appears to be superior to 2-eicosapentaenoyl-phosphatidylcholine as to the efficiency for increasing EPA levels in total
plasma phospholipids and plasma cholesteryl esters. 相似文献