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1.
Synthetic cholesteryl 5-oxovalerate and 9-oxononanoate were used as reference standards for the isolation and identification
of cholesteryl ester core aldehydes fromtert-butyl hydroperoxide/Fe++ oxidation of synthetic and natural cholesteryl esters. The core aldehydes were recovered from the peroxidation products by
thin-layer chromatography as the free aldehydes or the 2,4-dinitrophenylhydrazones and were identified, respectively, by gas-liquid
chromatography (GLC) and by GLC combined with mass spectrometry (GC/MS) or by reverse-phase high-performance liquid chromatography
(HPLC) and by HPLC with MS (LC/MS). The core aldehydes produced by peroxidation of cholesteryl linoleate were identified as
mainly 9-oxononanoates of cholesterol and oxycholesterols, with smaller amounts of the 8-oxooctenoates, 10-oxodecenoates,
11-oxoundecenoates and 12-oxododecenoates. Peroxidation of cholesteryl arachidonate yielded 5-oxovalerates of cholesterol
and the oxycholesterols as the main products with smaller amounts of the 4-oxobutyrates, 6-oxohexenoates, 7-oxoheptenoates,
8-oxooctenoates, 9-oxononenoates, 9-oxononadienoates and 10-oxodecadienotes. The oxycholesterols resulting from the peroxidation
of the steroid ring were identified as mainly 7-keto-, 7α-hydroxy- and 7β-hydroxy-cholesterols and 5α, 6α-and 5β,6β-epoxy-cholestanols.
Cholesteryl palmitate and oleate did not yield core aldehydes in the present peroxidation system. In these esters, the sterol
and linoleic acid moieties appeared to be oxygenated at about the same rate, while the arachidonic acid moiety reacted more
rapidly than did the sterol moiety. 相似文献
2.
The molecular species of TAG core aldehydes (aldehydes still esterified to parent molecules) were detected and quantified
in dietary-quality sunflowerseed oil autoxidized for 0‐18 d at 60°C in the dark. The analyses were performed by reversed-phase
HPLC with UV (358 nm) absorption or light scattering and electrospray ionization-MS (ESI/MS) detection following preparation
of the dinitrophenylhydrazone derivatives. Aldehyde production, as estimated by UV and ESI/MS, increased gradually over the
18-d period following a rapid initial destruction of the core aldehydes accumulated during storage of the commercial oil at
10°C for 3 mon. The contents of hydroperoxides and hydroperoxide core aldehyde combinations were estimated to account for
about 5% of total TAG, quantified as area in the chromatographic trace, after 18 d of autoxidation as estimated by an evaporative
light scattering detector (ELSD). The major species of core aldehydes were tentatively identified as 9-oxononanoyl (70%)-,
12-oxo-9,10-epoxydodecenoyl (10%)-, and 13-oxo-9,11-tridecadienoyl (5%)-containing acylglycerols, plus smaller amounts of
simple and mixed chain-length dialdehydes, and hydroxy and epoxy monoaldehyde-containing acylglycerols (15% of total). Quantitatively,
the core aldehydes made up 2–12 g/kg of oil by UV detection and 2–9 g/kg of oil by EsI/MS detection, whereas the hydroperoxides
measured in the unreduced state by HPLC with ELSD were estimated at 200 g/kg after 18 d of autoxidation. The major hydroperoxides
of sunflowerseed oil were as previously identified. 相似文献
3.
Selected elution factors were determined for model oxotriacylglycerols as an aid in identification of the peroxidation products
of natural triacylglycerols by reverse-phase high-performance liquid chromatography (HPLC) with electrospray mass spectrometry
(LC/ES/MS). For this purpose synthetic triacylglycerols of known structure were converted to hydroperoxides, hydroxides, epoxides,
and core aldehydes and their dinitrophenylhydrazones by published procedures. The oxotriacylglycerols were resolved by normal-phase
thin-layer chromatography and reverse-phase HPLC, and the identities of the oxotriacylglycerols confirmed by LC/ES/MS. Elution
factors of oxotriacylglycerols were determined in relation to a homologous series of saturated triacylglycerols, ranging from
24 to 54 acylcarbons, and analyzed by reverse-phase HPLC, using a gradient of 20–80% isopropanol in methanol as eluting solvent
and an evaporative light-scattering detector. It was shown that the elution times varied with the nature of the functional
group and its regiolocation in the triacylglycerol molecule. A total of 31 incremental elution factors were calculated from
chromatography of 33 oxygenated and nonoxygenated triacylglycerol species, ranging in carbon number from 36 to 54 and in double-bond
number from 0 to 6. 相似文献
4.
Autoxidation of polyunsaturated triacylglycerols. IV. Volatile decomposition products from triacylglycerols containing linoleate and linolenate 总被引:4,自引:0,他引:4
Trilinoleoylglycerol (LLL), trilinolenoylglycerol (LnLnLn) and four synthetic triacylglycerols were autoxidized and the volatile
products were investigated to determine the effect of fatty acid glyceride position on the mechanism of hydroperoxide decomposition.
Capillary gas chromatography provided a sensitive method to follow the volatile oxidation products of mixtures of LLL and
LnLnLn and of synthetic triacylglycerols containing linoleate and linolenate in different known positions. The relative amount
of linoleate oxidation was determined by analyzing for hexanal, 2-heptenal and 2,4-decadienal, and the relative amount of
linolenate oxidation by analyzing for 2,4-heptadienal and 2,4,7-decatrienal. The volatiles from pure monohydroperoxides of
LLL and LnLnLn were compared with those of the corresponding triacylglycerols by capillary gas chromatography. Significant
differences in the distribution of volatile products were observed depending on the triacylglycerols precursor. A 1∶1 mixture
of LLL and LnLnLn autoxidized at 40°C showed an equal contribution of linolenate and linoleate volatiles at a peroxide value
of 34. The synthetic triacylglycerols LLnL and LLLn (L, linoleic; Ln, linolenic acid) formed initially about the same total
volatiles, whereas LnLnL formed more volatiles than LnLLn. The ratio Ln to L volatile products was the same for the diL triacylglycerols,
and higher for LnLnL than for LnLLn. This new information should permit us to better understand the influence of triacylglycerol
structure on the relative oxidative stability of unsaturated triacylglycerols.
Presented in part at the 80th Annual American Oil Chemists' Meeting, Cincinnati, OH, May 3–6, 1989. 相似文献
5.
Three dimensional amorphous mesoporous material, TUD-1 with different Cu-loading were prepared by using triethanolamine (TEA)
as cheap, small, bi-functional template which acts as a mesoporous directing agent as well as an anchoring agent for copper
active sites on the mesoporous wall. The materials thus prepared have been characterized by X-ray diffraction, N2 sorption, FT-IR, TEM, DR-UV–Vis and ICP-OES. The catalytic activities of the prepared material (CuTUD-1) were tested in liquid
phase oxidation of ethylbenzene with tert-butyl hydroperoxide (TBHP) as an oxidant. Influence of various reaction parameters such as time, temperature, Si to Cu ratio,
oxidant and solvent were studied. Isolated framework substituted Cu sites are active for ethylbenzene conversion (35.2%) with
67% selectivity towards acetophenone. 相似文献
6.
A new direct conversion of aldehydes to amides has been realized, in the presence of iron(III) chloride as a catalyst and using tert‐butyl hydroperoxide (TBHP) as an oxidant. Both aliphatic and aromatic aldehydes were successfully reacted with variously mono‐ and di‐substituted N‐chloroamines. The methodology has a wide substrate scope, uses cheap and easily available reagents and is characterized by short reaction times. 相似文献
7.
N. V. Yanishlieva E. M. Marinova V. G. Raneva V. Partali H. -R. Sliwka 《Journal of the American Oil Chemists' Society》2001,78(6):641-644
The oxidation kinetics of sunflower oil (SO) and pure triacylglycerols of sunflower oil (TGSO) in the presence of different
concentrations (0.0008–0.02%, 1.9–32.7×10−5 M) of β-apo-8′-carotenoic acid (CA), ethyl β-apo-8′-carotenoate (EC), and β-apo-8′-carotenoylglycerol (CG) were studied.
The process was performed at high (kinetic regime) and low (diffusion regime) oxygen concentrations at room temperature and
at 100°C and in the dark and in daylight. CA, EC, and CG were not antioxidants in TGSO systems. However, the carotenoid derivatives,
especially CA, increased the stability of tocopherol-containing SO at room temperature and in daylight. The stabilization
effect was more evident in a kinetic regime of oxidation. The synergism between the carotenoids and tocopherols was characterized
by the increase of the stabilization factor F and activity A. F and A were highest for CA (F=1.2–5.5, A=2.4–78.6), followed by EC (F=1.2–3.5, A=1.7–14.6) and CG (F=1.1–2.1, A=1.6–5.5) in the kinetic regime for SO exposed to daylight at room temperature.
Presented at the 91st AOCS Annual Meeting & Expo, April 25–28, 2000, San Diego, California. 相似文献
8.
Kangming Ma F. R. van de Voort A. A. Ismail Hualong Zhuo Binjing Cheng 《Journal of the American Oil Chemists' Society》2000,77(6):681-685
A Fourier transform infrared (FTIR) spectrometer equipped with an attenuated total reflectance (ATR) sample handling accessory
was used to rapidly monitor the peroxide value (PV) of oils undergoing catalytic oxidation to produce sulfonated fatliquors
used in the leather industry. PV quantitation was based on the stoichiometric reaction of triphenylphosphosphine (TPP) with
hydroperoxides to produce triphenylphosphine oxide (TPPO). By using a germanium ATR accessory that has a very short effective
pathlength, the spectral contributions of the base oil could be subtracted out, eliminating any oil-dependent intereferences
as well as providing a facile means of observing the spectral changes associated with the TPP/TPPO reaction. A calibration
was devised by adding a constant amount of TPP-saturated chloroform to oils containing varying amounts of tert-butyl hydroperoxide (TBHP) to produce TPPO that had a measurable band at 1118 cm−1. this band was linearly related to TBHP concentration and the calibration devised had an SD of ∼3.4 PV over the range of
0–250 PV. The ATR-PV method was standardized and the spectrometer programmed using Visual Basic to automate the analysis.
the automated FTIR-ATR method was found to be a convenient means of tracking PV of oils undergoing oxidation, and the results
correlated well with the PV values obtained using the AOAC iodometric method (r=0.94). The FTIR-ATR PV methodology provides a simple means of monitoring the PV of oils undergoing rapid oxidation and could serve
as a quality-control tool in the production of sulfonated oils for the leather industry. 相似文献
9.
Sjofn Sigurgisladottir Santosh P. Lall Christopher C. Parrish Robert G. Ackman 《Lipids》1992,27(6):418-424
Salmonid fish require long-chain n−3 fatty acids in their diet. The digestibility of different chemical forms of fish oil
fatty acids, fed as triacylglycerols, free fatty acids or ethyl esters, was examined in 300 g farmed Atlantic salmon (Salmo salar) using cholestane as an indicator of fat absorptionin lieu of the chromium oxide (Cr2O3) which is commonly used as a marker in digestibility studies. It was established that the two digestibility markers gave
similar results. Conveniently, cholestane does not require a separate analysis if fatty acids are to be determined by appropriate
gas-liquid chromatography. The long-chain polyunsaturated fatty acids were particularly well absorbed, the apparent digestibility
being 90–98% when feeding triacylglycerols or free fatty acids. However, the digestibility of monounsaturated fatty acids
(75–94%) was lower, and lower still for saturated fatty acids (50–80%). Ethyl esters of fatty acids were significantly less
well absorbed (P<0.05) than were the corresponding fatty acids in free acid or triacylglycerol form. Irrespective of dietary fat type, only
free fatty acids were identified in feces, indicating total hydrolysis of triacylglycerols and ethyl esters.
Presented in part at the World Aquaculture Society meeting, June 10–14, 1990, Halifax, Canada. 相似文献
10.
W. E. Neff T. L. Mounts W. M. Rinsch H. Konishi 《Journal of the American Oil Chemists' Society》1993,70(2):163-168
The photooxidation of soybean oil was determined and correlated with triacylglycerol composition and structure. Purified triacylglycerols
were photooxidized at room temperature under fluorescent light. Rates of peroxide formation and total headspace volatiles
were related positively (P<0.5 significance) to oxidizability (r=0.75, r=0.76); content of linolenic acid (r=0.80, r=0.85) and linoleic acid (r=0.61,
r=0.57); linoleic acid on carbon 2 (r=0.64, r=0.64); and average number of double bonds (r=0.76, r=0.76). Negative correlations
were observed with respect to oleic acid (r=−0.70, r=−0.70). Soybean oil stability was decreased by linolenic acid-containing
triacylglycerols and increased by oleic acid-containing triacylglycerols. Trilinoleoylglycerol and dilinoleoyl-oleoylglycerol
were the most important oxidation product precursors. However, for high-linolenic acid soybean oil, dilinoleoyl-linolenoylglycerol
and trilinoleoylglycerol were the most important oxidation product precursors. The most abundant volatile produced from thermal
decomposition at 140°C of photooxidized triacylglycerols was 2-heptenal, except for high-linolenic acid oils, where the most
abundant volatile was propanal. The photooxidative stability of soybean oil triacylglycerols with respect to composition and
structure is of interest for the development of soybean varieties with oils of improved odor and flavor stability.
Presented at the 20th ISF World Congress 83rd Annual American Oil Chemists’ Society Meeting, May 10–14, 1992, Toronto, Canada. 相似文献
11.
Jan Kyselka Klára Cihelková Daise Lopes-Lutz Josef Chudoba Tereza Váchalová Katsiaryna Alishevich Iveta Hrádková Markéta Berčíková Monika Mikolášková Vladimír Filip 《European Journal of Lipid Science and Technology》2021,123(3):2000228
The aim of the present study is to describe the mechanism controlling heat-induced formation of sunflower oil triacylglycerol and fatty acid methyl ester oligomers. The unique combination of high-performance size-exclusion chromatography with hyphenated electrospray ionization mass spectrometry (MS), atmospheric pressure chemical ionization-MS, and high-temperature gas chromatography-MS techniques allows differentiating between radical coupling species and Diels–Alder cycloadducts. Targeted analysis of thermally degraded sunflower oils confirms the exact structures of various acyclic oligomers accompanied by less-abundant products of pericyclic transformations. A series of model experiments simulate the impact of dienophile nature on the course of Diels–Alder reactions. Thus, α-tocopherylquinone, δ-tocopherylquinone, and methyl-(E)-11-oxoundec-9-enoate are synthesized as naturally occurring dienophiles bearing electron-withdrawing groups. The geometry of poor dienophiles does not affect concerted cyclization, while the structure of electron deficient dienophiles can overcome low reactivity. Practical Application: In the absence of oxygen, heat-induced degradation of polyunsaturated triacylglycerols proceed predominantly via a radical pathway, whereas concerted reactions represent minor mechanisms. Sunflower oil triacylglycerol molecules in the system without propagation stage can be effectively protected by natural and/or synthetic antioxidants. Application of chelates is also recommended. However, antioxidant-derived quinones, such as α-tocopherylquinone, can enter the Diels–Alder reaction even more easily than dienophiles without electron-withdrawing groups. Unsaturated core aldehydes possess the same reactivity. Examination of the mechanism controlling high-temperature degradation of triacylglycerols is especially important for processing engineers in edible oil refineries and food technologists. New perspective may help them to minimize undesirable changes in polyunsaturated species. 相似文献
12.
Karsten Krohn Klaus Steingrver Ingeborg Vinke 《Advanced Synthesis \u0026amp; Catalysis》1999,341(1):62-64
Enolsilyl ethers ( 4, 6, 8, 10, 12, 14 ) are chlorinated to the α-monochloro ketones ( 5, 7, 9, 11, 13, 15 ) with tert-butyl hydroperoxide in the presence of dichlorotitanium diisopropoxide in 69 — 92% yield 相似文献
13.
Ana Maria P. Lottenberg Helena C. F. Oliveira Edna R. Nakandakare Eder C. R. Quintão 《Lipids》1992,27(5):326-330
The mechanism by which ω3 fatty acids lower plasma triacylglycerol levels was investigated. Rats were fed fish oil, olive
oil (10% fat by weight) or a nonpurified diet 4% fat by weight) for 15 days. Lipoprotein lipase was inhibited by intra-arterial
administration of Triton WR 1339 to estimate hepatic triacylglycerol output. Rats fed the olive oil diet showed a higher rate
of triacylglycerol formation than rats fed the ω3 fatty acid diet or the low-fat diet. All three groups showed identical rates
of removal from plasma of intraarterially administered artificial chylomicrons that had simultaneously been labeled with cholesteryl
[1-14C]oleate and [9,10(n)-3H]triolein. Liver radioactivity and total fat content were lowest in rats fed the fish oil diet, indicating that ω3 fatty
acids were preferentially metabolized in liver. Chylomicrons obtained from donor rats fed either fish oil containg [14C]cholesterol or olive oil containing [3H]cholesterol were removed at similar rates when infused together intraarterially into recipient animals. A slower formation
of plasma very low density lipoprotein triacylglycerols in rats fed fish oil is probably due to a faster rate of oxidation
of the fatty acid chains in the liver resulting in decreased plasma triacylglycerol concentrations. 相似文献
14.
In view of the previously reported changes in the fatty acid composition of maternal liver triacylglycerols in late pregnancy,
changes in the composition of maternal liver triacylglycerol species were assessed in rats fed a semipurified diet during
pregnancy. Between day 18 and day 21 of pregnancy, total maternal liver triacylglycerols increased by 50%. Triacylglycerol
species with a total acyl carbon number (C) of 50 or 60 (C50, C60) remained unchanged while C48 and C52–C58 were relatively
increased. The individual triacylglycerol species containing one, two or three linoleoyl moieties were incompletely recovered
using a polar high temperature gas-liquid chromatography (GLC) column. Nevertheless, at day 21 compared to day 18, the linoleoyl-containing
species were relatively increased by 62–463%, while tripalmitin was decreased by 38%. Our data suggest that despite an adequate
intake of linoleic acid (25 g/kg in the diet), maternal hepatic triacylglycerol content of linoleic acid decreased during
mid-pregnancy but increased significantly toward term possibly in preparation for the transfer of linoleic acid to the neonate
during lactation. 相似文献
15.
Hiromi Yoshida 《Lipids》1984,19(12):936-941
Molecular species and fatty acid distributions of triacylglycerols obtained from cotyledons of soybean seedlings were investigated.
Changes observed in triacylglycerol content were closely related to levels of total lipids present in the cotyledons. At day
12 of seedling growth, ca. 85% of triacylglycerols had been consumed. Immediately after the beginning of imbibition the oil
consisted of triacylglycerols with even carbon numbers (from C-50 to C-60) based on the combined length of the fatty acyl
chains present in a triacylglycerol. The dominant components throughout germination were C-52 and C-54 triacylglycerols. Fourteen
molecular species of triacylglycerols were identified in the cotyledons. As soybean seedlings grew, the percentages of triacylglycerols
decreased to 0.9–36.2% during the 12 days. Triacylglycerols containing one or more saturated fatty acids were hydrolyzed slightly
faster than other species. Unsaturated fatty acids were dominant in the 2-position throughout germination. These results suggest
the mechanism of initial triacylglycerol hydrolysis may be different in various molecular species. 相似文献
16.
Different emulsion polymerization processes allowed variation in the microstructure of composite natural rubber (NR)-based latex particles. A prevulcanized and a not-crosslinked natural rubber latex were coated with a shell of crosslinked poly(methyl methacrylate) (PMMA) or polystyrene (PS). The bipolar redox initiating system tert-butyl hydroperoxide/tetraethylene pentamine promoted a core–shell arrangement. Furthermore, PS subinclusions were introduced into the NR core. The initiators used for the subinclusion synthesis were azobisisobutyronitrile at high temperature and a redox initiation system consisting of tert-butyl hydroperoxide/dimethylaniline at low temperature. The morphology of the resulting latex interpenetrating networks (IPN) was characterized by transmission electron micros-copy (TEM) and scanning electron microscopy (SEM). Different staining methods allowed us to increase the contrast between the NR phase and the secondary polymers in the composite latex particles. A semicontinuous feeding process decreased the PS subinclusions size by a factor of 6 in comparison with a batch reaction. Depending on the NR/styrene swelling ratio, the crosslinking degree, and the polymerization temperature used, distinct differences of the phase arrangement of polymers in the latex particles were revealed. © 1996 John Wiley & Sons, Inc. 相似文献
17.
The effect of the γ-linolenic acid (18:3n-6) residue on the elution of triacylglycerols on a 25% cyanopropyl-25% phenyl-50%
methylpolysiloxane stationary phase was confirmed by using capillary supercritical fluid chromatography-atmospheric pressure
chemical ionization mass spectrometry [cSFC-(APCI)MS]. The general elution rule on this stationary phase is that triacylglycerols
having the same ACN+2n value coeluted (ACN-acyl carbon number and n=combined number of double bonds in the acyl chains). The different effect of γ- and α-linolenic acid residues on the retention
of triacylglycerols and the use of cSFC-(APCI)MS allowed the study of the number of different linolenic acid residue isomer
combinations in triacylglycerols with an identical ACN and degree of unsaturation. Stearidonic acid (18:4n-3) residue was
found to have a similar effect on the retention behavior of triacylglycerols as that of γ-linolenic acid residue. The abundance
of the [M-RCOO]+ ion, formed by the loss of one fatty acid moiety of a triacylglycerol, was found to be clearly higher in the case of γ-isomer
of the linolenic acid than that of α-isomer in the identical regiospecific position. This indicates that the distance of the
double bonds from the glycerol backbone in the acyl chain affects the stability of a triacylglycerol molecule in the (APCI)MS
system. The triacylglycerol composition and the fatty acid combinations of triacylglycerols were found to be almost identical
in black currant (Ribes nigrum) and alpine currant (R. alpinum) seed oils. 相似文献
18.
Autoxidation of polyunsaturated triacylglycerols. III. Synthetic triacylglycerols containing linoleate and linolenate 总被引:7,自引:0,他引:7
Four triacylglycerols containing linoleate (L) and linolenate (Ln) in specific positions were synthesized to determine the
effect of fatty acid position on their relative rates and products of autoxidation. Analyses by reversedphase high performance
liquid chromatography (HPLC) showed that autoxidation of L- and Ln-containing triacylglycerols form monohydroperoxides and
hydroperoxy epidioxides as the main products. The peroxyl radicals of internal 12- and 13-mono-hydroperoxides of Ln triacylglycerol
components cyclized rapidly and their relative triacylglycerol position had no influence on their rates of cyclization. A
good linear relation was obtained between total HPLC peak areas (detected at 235 nm) of the main oxidation products and peroxide
values. Reversed phase HPLC analyses thus provide a useful method to estimate oxidation of polyunsaturated triacylglycerols.
The ratios of Ln to L mono-hydroperoxides were twice the ratios of Ln to L in the triacylglycerol substrates. Ln triacylglycerol
components, therefore, oxidized twice as much as the L components. At 40°C, LnLnL oxidized slightly faster than LnLLn with
respective induction periods of 45 and 47 hr. LLnL oxidized faster than LLLn with respective induction periods of 56 and 60
hr. Dilinolenoyl-linoleoylglycerols are, therefore, slightly less stable to oxidation when Ln is in the 1,2- than the 1,3-triacylglycerol
position. Dilinoleoyl-linolenoylglycerols are less stable when L is in the 1,3- than the 1,2-triacylglycerol position.
Presented in part at the 80th Annual American Oil Chemists' Society Meeting, Cincinnati, Ohio, May 3–6, 1989 相似文献
19.
Treatment of isomeric methyl linoleate hydroperoxides with a Lewis acid, BF3, in anhydrous ether led to a carbon-to-oxygen rearrangement that caused cleavage into shorter-chain aldehydes. Methyl (9Z,11E)-13-hydroperoxy-9,11-octadecadienoate afforded mainly hexanal and methyl (E)-12-oxo-10-dodecenoate, whereas methyl (10E,12Z)-9-hydroperoxy-10,12-octadecadienoate cleaved into 2-nonenal and methyl 9-oxononanoate. The 2 aldehydes obtained from each
hydroperoxide isomer were uncharacteristic of the complex volatile profile usually obtained by β-scission of oxy radicals
derived from homolysis of the hydroperoxide group. Rather, the reaction resembled the one catalyzed by the plant enzyme, hydroperoxide
lyase.
Presented in part at the American Oil Chemists' Society Meeting, Chicago, Illinois, May 8–12, 1983.
The mention of firm names or trade products does not imply that they are endorsed or recommended by the USDA over other firms
or similar products not mentioned. 相似文献
20.
The influence of dietary fish oil containing n−3 polyunsaturated fatty acids on the biosynthesis of triacylglycerol relative
to total individual phospholipids was studied in rat liverin vivo. The dietary lipid (10% by weight of diet) was either sunflower oil enriched in linoleic acid (SO group) or MaxEPA fish oil/sunflower
oil, 9∶1 by weight (FO group) enriched in eicosapentaenoic acid (EPA, 20∶5n−3) plus docosahexaenoic acid (DHA, 22∶6n−3). After
a 3-week feeding period, the triacylglycerol content (in μmmol/g liver) was 44% lower in the FO group relative to the SO animals.
Thein vivo incorporation of [3H]glycerol into individual hepatic lipids resulted in triacyl-glycerol/total phospholipid radioactivity ratios of 2.1 and
0.9 for the SO and FO groups, respectively. These results indicate an inhibitory effect of dietary EPA/DHA on triacylglycerol
relative to phospholipid synthesis from intermediary 1,2-diacylglycerol in rat liverin vivo. This metabolic alteration was accompanied by a substantially lower amount (in μmol/g liver) of arachidonic acid and higher
levels of EPA plus DHA in the triacylglycerol, choline glycerophospholipid (CGP), and ethanolamine glycerophospholipid (EGP)
of the FO group. A moderately higher labelling of the EGP from [3H]glycerol was observed in the FO as compared to the SO group (as evidenced by CGP/EGP radioactivity ratios of 1.3∶1 and 1.8∶1,
respectively). The present study providesin vivo evidence for a dampening effect of dietary fish oil on the synthesis of liver triacylglycerol relative to phospholipid and
a moderate alteration ofde novo synthesis of individual phospholipids.
Presented in part at the 80th Annual Meeting of the AOCS in Cincinnati, Ohio (May, 1989). 相似文献