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1.
The yeast Saccharomyces cerevisiae was cultivated in the presence of free CLA that was either a pure trans-10, cis-12 isomer, a pure cis-9, trans-11 isomer, or a 1∶1 mixture of the two, and the influence of these supplementations on the content and FA composition of
the lipids in the yeast was determined. Neither the pure isomers nor their 1∶1 mixture influenced the growth of the yeast,
but the trans-10, cis-12 isomer reduced the amount of cellular lipids by 40%. The reduction in total cellular lipids by the trans-10, cis-12 CLA was due to a reduction in TAG. Both of the isomers were incorporated into the yeast lipids, reaching a proportion
of about 33% in TAG. With the incorporation of CLA, the yeast reduced the amount and desaturation of endogenously synthesized
FA. These clear and pronounced isomer-specific effects of CLA on the yeast suggest that yeast might be a useful model to obtain
a more comprehensive view of the mechanisms of the action of CLA on lipid metabolism. 相似文献
2.
The distribution of hydroperoxide isomers generated by photo-oxidation of natural lipids impregnated on the surface of dried
seaweed previously exposed to visible light and without added photosensitizer were studied. The surface of dried seaweed was
impregnated with linoleic acid methyl ester, and the sample was divided into two parts. One part was exposed to light from
a 100-W tungsten bulb (4500 lux) in a low-temperature room (5°C). The other part was kept in the dark as a control. Positional
isomers of the hydroperoxides generated from the impregnated linoleic acid methyl ester were separated individually by HPLC
and further identified by MS. The dried seaweed kept in the dark contained four hydroperoxide isomers, namely, 13-hydroperoxy-cis-9, trans-11-octadecadienoate, 13-hydroperoxy-trans-9, trans-11-octadecadienoate, 9-hydroperoxy-trans-10,cis-12-octadecadienoate, and 9-hydroperoxy-trans-10, trans-12-octadecadienoate. For the dried seaweed exposed to light, the oxidized lipids contained not only the same four isomers,
but also 12-hydroperoxy-cis-9, trans-13-octadecadienoate and 10-hydroperoxy-trans-8,cis-12-octadecadienoate. When fresh seaweed was dried in the sunlight, the formation of 12-cis,trans- and 10-cis,trans-hydroperoxides of naturally occurring methyl linoleate was verified. Dried seaweed was then impregnated with eicosapentaenoic
acid ethyl ester and exposed to light. Light exposure also generated certain hydroperoxide isomers attributable to singlet
oxygen oxidation, namely, 6-hydroperoxy-trans-4,cis-8, cis-11,cis-14,cis-17-ethyl and 17-hydroperoxy-cis-5,cis-8,cis-11, cis-14,trans-18-ethyl eicosapentaenoate. When dried sea-weed without any impregnated lipids was exposed to the light for 24 h in a cold
room (5°C), characteristic isomers, including both the 20-carbon FA isomers 6-OOH and 17-OOH as well as the 18-carbon FA isomers
10-OOH and 12-OOH, were detected in the light-exposed sample but were not found in the control. These results clearly show
that singlet oxygen oxidation of lipids occurred in the seaweed exposed to light. We concluded that this lipid oxidation was
catalyzed by chlorophyll as a photosensitizer in seaweed. 相似文献
3.
Isomeric CLA exhibit several significant biological activities in animals and humans and are easily isomerized to their corresponding
t,t-CLA isomers during methylation with various acid-catalyzed reagents. To minimize such isomerization and provide a valid quantification
of human plasma CLA content, several methylation methods were tested. Plasma neutral lipid, nonesterified FA (NEFA), and polar
lipid classes were separated into the following fractions: (i) cholesteryl ester (CE, 1.2 mg/12 mL, 37.5% lipids), (ii) TAG
(0.8 mg/12 mL, 25% lipids), (iii) NFFA (0.2 mg/12 mL, 6.2% lipids), (iv) MAG/DAG/cholesterol (0.3 mg/12 mL, 9.4% lipids),
and (v) phospholipid (PL, 0.5 mg/20 mL, 15.6% lipids). Data showed that c9,t11-CLA found in TAG, MAG/DAG/cholesterol, and PL fractions were converted to methyl esters with sodium methoxide within 2
h at 55°C. However, the c9,t11-CLA in the CE fraction could not be completely converted to methyl esters by sodium methoxide/acetylchloride in methanol
or methanolic KOH; instead, CE was treated with sodium methoxide and methyl acetate in diethyl ether for 1 h. NEFA were converted
to methyl esters with trimethylsilyldiazomethane (TMSDAM). All reaction mixtures were monitored by TLC prior to GLC analysis.
The highest enrichment of c9,t11-18∶2 (% FA) was in TAG (0.31%), followed by CE (0.14%) and PL (0.13%). The above methylation methods were then applied
to a small subset (n=10) of nonfasting plasma lipid fractions to confirm the applicability of these data. Results from this subset of samples
also indicated that the greatest enrichment of c9,t11-CLA was present in the TAG fraction (0.39%), followed by CE (0.27%) and PL (0.22%). These data indicate that different
plasma fractions have different c9,t11-CLA contents. 相似文献
4.
Edouard Kraffe Jacques Grall Elena Palacios Citlali Guerra Philippe Soudant Yanic Marty 《Lipids》2010,45(5):437-444
The present study aimed to elucidate the effective phylogenetic specificity of distribution of a cis-4,7,10, trans-13-22:4 (22:4(n-9)Δ13trans) among pectinids. For this purpose, we extended the analysis of membrane glycerophospholipids FA composition to 13 species
of scallops, covering 11 genera and 7 tribes representatives of the three subfamilies Chlamydinae, Palliolinae and Pectininae
and the subgroup Aequipecten. In species belonging to the subfamily Pectininae and the Aequipecten subgroup, 22:4(n-9)Δ13trans was found in substantial amounts, but it was absent in other species belonging to the subfamilies Chlamydinae and Palliolinae.
Homologous non-methylene-interrupted (NMI) FA, also hypothesized to differ along phylogenetic lines in bivalves, were totally
absent or present only in trace amounts in representatives of the Aequipecten subgroup but ranged from 0.3 to 4.5% of the
total FA in Pectinidae, Chlamydinae, and Palliolinae subfamilies. The species-specific occurrence of NMI and 22:4(n-9)Δ13trans FA in membrane lipids of pectinids agrees with the most recent phylogenies based on shell morphology and molecular characteristics.
We examined the potential timing of the appearance of 22:4(n-9)Δ13trans in pectinids on a geologic time scale. 相似文献
5.
In ruminants, cis and trans C18:1 isomers are intermediates of fatty acid transformations in the rumen and their relative amounts shape the nutritional
quality of ruminant products. However, their exact synthetic pathways are unclear and their proportions change with the forage:concentrate
ratio in ruminant diets. This study traced the metabolism of vaccenic acid, the main trans C18:1 isomer found in the rumen, through the incubation of labeled vaccenic acid with mixed ruminal microbes adapted to different
diets. [1-13C]trans-11 C18:1 was added to in vitro cultures with ruminal fluids of sheep fed either a forage or a concentrate diet. 13C enrichment in fatty acids was analyzed by gas-chromatography-mass spectrometry after 0, 5 and 24 h of incubation. 13C enrichment was found in stearic acid and in all cis and trans C18:1 isomers. Amounts of 13C found in fatty acids showed that 95% of vaccenic acid was saturated to stearic acid after 5 h of incubation with the concentrate
diet, against 78% with the forage diet. We conclude that most vaccenic acid is saturated to stearic acid, but some is isomerized
to all cis and trans C18:1 isomers, with probably more isomerization in sheep fed a forage diet. 相似文献
6.
The objective of the present study was to compare the effects of cis-9,trans-11 + trans-8,cis-10 conjugated linoleic acid (CLA) mixture to those of cis-9,trans-11 + trans-10,cis-12 CLA mixture and linoleic acid (LA) on lipoprotein profile, hepatic lipids, body composition and digestibility of dietary
fat in hamsters (n = 17) fed diets containing 2% of experimental fat (w/w) for 28 days. The cis-9,trans-11 + trans-10,cis-12 CLA mixture showed higher LDL cholesterol concentrations than LA and the cis-9,trans-11 + trans-8,cis-10 CLA mixture. The cis-9,trans-11 + trans-8,cis-10 CLA mixture induced similar plasma LDL cholesterol and hepatic lipid concentrations, and coefficient of digestibility
as LA, indicating no effect of the trans-8,cis-10 CLA isomer on these lipid parameters. On the other hand, the cis-9,trans-11 + trans-8,cis-10 CLA mixture induced higher plasma VLDL cholesterol and triglycerides than LA and the cis-9,trans-11 + trans-10,cis-12 CLA mixture. The cis-9,trans-11 + trans-8,cis-10 CLA mixture also induced the highest plasma glucose concentrations compared with the two other groups, indicating an impairment
of glycemic control. No differences in body composition were noted between the three groups. The present results thus show
that the cis-9,trans-11 + trans-8,cis-10 CLA mixture can deteriorate plasma VLDL cholesterol and triglycerides in hamsters, possibly due to an increased flux of
glucose. 相似文献
7.
The autoxidation processes of the cis-9,trans-11 (c9,t11) and trans-10,cis-12 (t10,c12) isomers of CLA were separately observed at ca. 0% RH and different temperatures. The t10,c12 CLA oxidized faster than the c9,t11 isomer at all tested temperatures. The first half of the oxidation process of t10,c12 CLA obeyed an autocatalytic-type rate expression, but the latter half followed first-order kinetics. On the other hand,
the entire oxidation process of c9,t11 CLA could be expressed by the autocatalytic-type rate expression. The apparent activation energies and frequency factors
for the autoxidation of the isomers were estimated from the rate constants obtained at various temperatures based on the Arrhenius
equation. The apparent activation energies for the CLA isomers were greater than those for the nonconjugated n−6 and n−3 PUFA
or their esters. However, the enthalpyentropy compensation held during the autoxidation of both the CLA and PUFA. This suggested
that the autoxidation mechanisms for the CLA and PUFA were essentially the same. 相似文献
8.
Marine lipid-based liposomes increase <Emphasis Type="Italic">in vivo</Emphasis> FA bioavailability 总被引:1,自引:0,他引:1
Liposomes made from an extract of natural marine lipids and containing a high n-3 PUFA lipid ratio were envisaged as oral
route vectors for FA supplements in order to increase PUFA bioavailability. The absorption of FA in thoracic lymph duct-cannulated
rats, after intragastric feeding of dietary fats in the form of liposomes or fish oil, was compared. Lipid and FA analyses
were also performed on feces. Five mole percent α-tocopherol was added to fish oil and incorporated into the liposome membrane.
The influence of α-tocopherol on FA lymph recovery was also investigated. In vivo, FA absorption in rats was favored by liposomes (98±1%) compared to fish oil (73±6%). In the same way, the DHA proportion
in lymph was higher after liposome ingestion (78%) than after fish oil ingestion (47%). However, phospholipid (PL) concentration
in lymph was not affected by the kind of dietary fat ingested, suggesting a PL regulation due to de novo TAG synthesis. The influence of the intramolecular distribution of n-3 PUFA in dietary lipids (TAG and PL) on the intramolecular
FA distribution in TAG of chylomicrons was also investigated. The results obtained showed that the distribution of n-3 PUFA
esterified on the sn-2 of chylomicron TAG depended on the lipid source administered. All these results correlated, at least partly, with in vitro liposome behavior under conditions that mimic those of the gastrointestinal tract. As a whole, this study pointed out that
marine PL may constitute an attractive material for the development of liposomes as oral PUFA supplements. 相似文献
9.
In order to measure exactly the trans-fatty acids content in food materials, a preparative group separation of cis- and trans-isomers of unsaturated fatty acid methyl esters (FAMEs) was achieved by an isocratic reversed-phase HPLC (RP-HPLC) method.
The trans-isomers of 16:1, 18:1, 18:2, 18:3, 20:1 and 22:1 FAMEs were readily separated from the corresponding cis-isomers by a COSMOSIL Cholester C18 column (4.6 mm I.D. × 250 mm, Nacalai Tesque) or a TSKgel ODS-100Z column (4.6 mm I.D. × 250 mm,
TOSOH), using acetonitrile as the mobile phase. This method was applied for determining the trans-18:1 fatty acid content in partially hydrogenated rapeseed oil. The methyl esters of cis- and trans-18:1 isomers of the oil were collected as two separate fractions by the developed RP-HPLC method. Each fraction was analyzed
by gas chromatography (GC) for both qualitative and quantitative information on its positional isomers. By a combination of
RP-HPLC and GC methods, a nearly complete separation of cis- and trans-18:1 positional isomers was achieved and the trans-18:1 fatty acid content was able to be evaluated more precisely than is possible by the direct GC method. The reproducibility
of cis- and trans-18:1 isomers fractionated by the RP-HPLC method was better than 98%. These results suggested that the preparative RP-HPLC
method developed in this study could be a powerful tool for trans-fatty acid analysis in edible oils and food products as an alternative to silver-ion chromatography. 相似文献
10.
Reinvestigation of the current FA composition of the regional freshwater sponge Baicalospongia bacillifera showed that the main measured isomer of EPA (14% of the total FA now detected) is, in fact, an unusual 5Z,8Z,11Z,14Z,18E-EPA. Two other isomers of this acid also present were identified as a novel 5Z,8Z,11Z,15Z,18E-EPA and the common methylene-interrupted 5Z,8Z,11Z,14Z,17Z-EPA (usually written simply as EPA). Isolation of these acids as their methyl ester derivatives was accomplished with the
use of a combination of silver-ion column chromatography and HPLC. The structure of the two new compounds was deduced from
GC-MS and detailed NMR data. Partial hydrazine reduction of all three isolated EPA esters followed by separation of cis/trans isomers of the resulting monoenoic acids and GC-MS analysis of their dimethyl disulfide adducts were used for determination
of the configuration and position of the double bonds. We may assume that the sponge B. bacillifera cannot receive these unusual EPA isomers directly from food sources (e.g., algal diatoms), and accordingly restructuring
of ordinary EPA to novel acids may take place in the sponge tissue. 相似文献
11.
Daphnia magna is a common crustacean that is adapted to brief speels of fasting. Lipids are naturally a major component of their diet and
are stored as energy reserves. However, there has been some controversy in the literature on the extent to which dietary lipids
are used directly for complex lipid formation in Daphnia. We examined lipid metabolism in D. magna by labeling the animals using [1-14C]acetate and then followed the turnover of radiolabeled lipids during a pulse chase. Daphnia were either fed or maintained without food during the chase period. The decrease in radioactivity during the chase was relatively
unaffected by feeding, although there were some differences in the distribution of radioactivity between lipid classes or
individual FA. The polar lipids, which were four times better labeled than nonpolar lipids, contained the most radioactivity
in the zwitterionic phosphoglycerides, PE and PC. Under the experimental conditions, the turnover of the polar membrane lipids
was unaffected by feeding. Within nonpolar lipids, TAG accounted for up to about 80% of the label, followed by DAG. Overall,
our data show that D. magna is capable of high rates of lipid radiolabeling de novo and, in addition, is able to use—and indeed may be dependent on—some dietary components such as the PUFA linoleate and α-linolenate.
The results also clearly show that Daphnia is able to tolerate brief spells of fasting (24 h) with very little change to its lipid metabolism. 相似文献
12.
The contents of total trans FA of sunflower oils at different stages of refining processes were determined by capillary GLC. The contents of 18∶1, 18∶2,
and 18∶3 trans acids were 0.22±0.03, 2.31±0.23, and 0.03±0.01%, respectively, in physically refined sunflower oils, and 0.05±0.01, 0.69±0.26,
and 0.02±0.01%, respectively, in chemically refined sunflower oils. The total trans FA contents drastically increased at the end of the physical refining process. The total trans FA contents of chemically refined sunflower oils were <1%. Because of the high temperature applied in the last stage of physical
refining, the content of total trans FA was higher than in chemically refined sunflower oils. The last-stage conditions should be carefully evaluated to reduce
the formation of trans FA during physical refining. 相似文献
13.
Amy Richards Chakra Wijesundera Phil Salisbury 《Journal of the American Oil Chemists' Society》2008,85(2):159-168
The effects of genotype and growing environment on the tocopherols and fatty acids (FA) of experimental Brassica juncea and B. napus breeding lines were investigated. For both species, with the exception of a few genotypes, the concentration ratio of γ-tocopherols
to α-tocopherol was practically constant. The genotype influenced the tocopherol concentration in B. napus, and to a lesser degree, B. juncea. The environment also had a similar effect, and a positive correlation existed between the daily maximum temperature and
the α-tocopherol concentration in B. napus. Genotype effects on the FA composition were significant for the conventional but not for Clearfield or triazine tolerant
traits of B. napus. The genotype had no effect on the FA of the B. juncea genotypes. In contrast, the growing environment had a significant influence on the FA composition of both species with apparent
influence from temperature and rainfall. For both species, the concentration of γ-tocopherol as well as total tocopherols
was inversely related to the 18:3 concentration, which could have resulted from opposite and independent effects of temperature
on the two variables. No relationship existed between the concentrations of tocopherol and the remaining unsaturated FA 18:1
and 18:2. The positional distribution of unsaturated FA within the oil triacylglycerol was a function of their total concentration. 相似文献
14.
Flore Dagorn Justine Dumay Gaëtane Wielgosz-Collin Vony Rabesaotra Michèle Viau Claude Monniot Jean-François Biard Gilles Barnathan 《Lipids》2010,45(3):253-261
Two tunicates, Eudistoma sp. and Leptoclinides uniorbis, collected from the tropical waters off Djibouti were investigated for lipids and phospholipid (PL) fatty acids. PL accounted
for 38.2% of the total lipids in Eudistoma sp. and for 30.2% in L. uniorbis. PL classes were quantified by normal-phase high-performance liquid chromatography using an evaporative light-scattering detector
and revealed essential differences. Eudistoma sp. contained mainly phosphatidylcholine (PC, 70.3% of total PL) and lysophosphatidylcholine (LPC, 11.9%) and was devoid
of phosphatidylserine (PS), whereas the major PL of L. uniorbis was PS (59.1%) followed by PC (22.5%) and LPC (8.8%). Gas chromatography–mass spectrometry analyses of fatty acid (FA) derivatives
revealed 38 FA in Eudistoma sp., and 35 FA in L. uniorbis, ranged from C12 to C24 chain lengths. Polyunsaturated FA accounted for 25.9% in Eudistoma sp. and for 32.3% in L. uniorbis. Interestingly, L. uniorbis contained a high percentage (16.7%) of the 20:5n-3 acid (8.9% in Eudistoma sp.) and the 18:4n-3 acid (4.1%). Significant levels of the 20:4n-6 acid were observed in both organisms (7.8 and 6.0% respectively).
Eudistoma sp. contained the rare 20:3n-7 acid (2.3%) only recorded to date in hydrothermal vent animals. The cyclopropane dihydrosterculic
acid was identified in both tunicates (0.7 and 0.5% respectively). These latter FA, together with some unusual branched saturated
and monounsaturated FA, revealed the occurrence of associated bacteria in the tunicates. Another noticeable feature was a
series of eight C16 to C18 aldehyde dimethylacetals revealing the presence of plasmalogens at 5.0% in Eudistoma sp. and 14.2% in L. uniorbis. The results of this study were compared with those previously published for other tunicates regarding mainly PL content
and FA composition. 相似文献
15.
Variations of <Emphasis Type="Italic">trans</Emphasis> octadecenoic acid in milk fat induced by feeding different starch-based diets to cows 总被引:1,自引:1,他引:1
The impact of starch sources differing in their velocities of ruminal degradation on the milk fat of dairy cows was studied.
The animals received diets containing a slowly degradable (potatoes) or rapidly degradable (wheat) starch concentrate (40%
of the dry matter) in a total mixed diet. Milk fat was the only animal performance factor affected: Cows produced significantly
less milk fat when fed the wheat diet than the potato diet (−3.3 g/kg, −122 g/d; P<0.05). With the wheat diet, milk fat was poorer in short-chain FA and richer in unsaturated longchain FA, especially in trans octadecenoic acid (4.4 vs. 2.7% of the total FA, P<0.05). A very large increase in the isomer trans-10 18∶1 (+1.46% of the total FA) was observed. Because no difference in volatile FA concentrations in the rumen was revealed,
the increase in trans octadecenoic acids, and particularly the isomer trans-10 18∶1, was associated with the larger postprandial drop in ruminal pH with wheat. Similar concentrate levels and FA profiles
in both diets indicated that the decrease in milk fat was due to changes in the ruminal environment. Quicker degradation of
wheat starch, and hence a greater drop in pH with this diet associated with the absence of any effect on volatile FA, strengthen
the hypothesis developed in the literature of enzyme inhibition via increased levels of trans octadecenoic acids, especially the trans-10 isomer. Hence, milk fat can be decreased with rapidly degradable starch sources and not only with high levels of concentrates
in the diet or added fat. More detailed work is necessary to elucidate the microorganisms involved and to determine whether
metabolic pathways similar to those reported for high-concentrate diets are involved. 相似文献
16.
Elena Pastor-Cavada Rocio Juan Julio E. Pastor Manuel Alaiz Javier Vioque 《Journal of the American Oil Chemists' Society》2009,86(4):329-335
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.
Evidence suggests that minor isomers of conjugated linoleic acid (CLA), such as trans8, cis10 CLA, can elicit unique biological effects of their own. In order to determine the effect of a mixture of t8, c10+c9, t11 CLA isomers on selected aspects of lipid metabolism, 3T3-L1 preadipocytes were differentiated for 8 days in the presence
of 100 μM linoleic acid (LA); t8, c10+c9, t11 CLA; t10, c12+c9, t11 CLA or purified c9, t11 CLA. Whereas supplementation with c9, t11 and t10, c12+c9, t11 CLA resulted in cellular triglyceride (TG) concentrations of 3.4 ± 0.26 and 1.3 ± 0.11 μg TG/μg protein, respectively (P < 0.05), TG accumulation following treatment with CLA mixture t8, c10+c9, t11 was significantly intermediate (2.5 ± 0.22 μg TG/μg protein, P < 0.05) between the two other CLA treatments. However, these effects were not attributable to an alteration of the Δ9 desaturation index. Adiponectin content of adipocytes treated with t8, c10+c9, t11 mixture was similar to the individual isomer c9, t11 CLA, and both the t8, c10+c9, t11 and c9, t11 CLA groups were greater (P < 0.05) than in the t10, c12+c9, t11 CLA group. Overall, these results suggest that t8, c10+c9, t11 CLA mixture affects TG accumulation in 3T3-L1 cells differently from the c9, t11 and t10, c12 isomers. Furthermore, the reductions in TG accumulation occur without adversely affecting the adiponectin content of these
cells. 相似文献
18.
J.-F. Butaud P. Raharivelomanana J.-P. Bianchini E. M. Gaydou 《Journal of the American Oil Chemists' Society》2008,85(4):353-356
The sandalwood kernels of Santalum insulare (Santalaceae) collected in French Polynesia give seed oils containing significant amounts of ximenynic acid, E-11-octadecen-9-oic acid (64–86%). Fatty acid (FA) identifications were performed by gas chromatography/mass spectrometry
(GC/MS) of FA methyl esters. Among the other main eight identified fatty acids, oleic acid was found at a 7–28% level. The
content in stearolic acid, octadec-9-ynoic acid, was low (0.7–3.0%). An inverse relationship was demonstrated between ximenynic
acid and oleic acid using 20 seed oils. Results obtained have been compared to other previously published data on species
belonging to the Santalum genus, using multivariate statistical analysis. The relative FA S. insulare composition, rich in ximenynic acid is in the same order of those given for S. album or S. obtusifolium. The other compared species (S. acuminatum, S. lanceolatum, S. spicatum and S. murrayanum) are richer in oleic acid (40–59%) with some little differences in linolenic content. 相似文献
19.
Two tunicates (Fudistoma bituminis and Cystodytes violatinctus, family Polycitoridae) were investigated for the FA content of their phospholipids. GC-MS analysis of their methyl esters
and N-acyl pyrrolidides revealed 40 FA in E. bituminis, and 26 in C. violatinctus. In both cases, the most abundant FA were the saturated ones (C10 to C18). Cystodytes violatinctus contained considerable oleic acid (20%). Both E. bituminis and C. violatinctus contained phytanic acid and Δ10-unsaturated FA, which had not previously been found in such organisms. The two tropical tunicates contained only trace amounts
of PUFA, which are usually predominant in this phylum. 相似文献
20.
The lipid and FA composition of the total lipids of the pearl oyster Pinctada fucata martensii, in different seasons and in different areas, were analyzed to clarify its lipid physiology and to estimate the possible
influence of its prey phytoplankton. TAG and sterols were the major components in the neutral lipids in all conditions, whereas
high levels of phospholipids (PE and PC) were found in the polar lipids. The major FA in the TAG in all samples were 14∶0,
16∶0, and 18∶0 as saturated FA (saturates); 16∶1n−7, 18∶1n−9, and 18∶1n−7 as monoenoic FA (monoenes); and 20∶4n−6 (arachidonic
acid: AA), 20∶5n−3 (EPA), and 22∶6n−3 (DHA) as PUFA. The major components found in the polar lipids were 16∶0 and 18∶0 as
saturates; 22∶2n−9, 15 and 22∶2n−7, 15 as non-methylene-interrupted dienes (NMID), and AA, 22∶3n−6, 9, 15, EPA, and DHA as
PUFA. Although it is a marine animal, characteristically high levels of AA were found in both the TAG and phospholipids. This
result suggests that lipids of P. fucata may be influenced by those of its phytoplanktonic prey. The increase in levels of NMID from TAG to PE with a decrease in
those of monoenes suggests that the tissues of this species are able to biosynthesize only the less unsaturated PUFA, such
as NMID. In particular, NMID derivatives are considered to be biosynthesized in the PE; thus, they might play a particular
role in the membrane, because NMID were characteristically localized only in the PE. 相似文献