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1.
K. H. Lee H. S. Yook J. W. Lee W. J. Park K. S. Kim M. W. Byun 《Journal of the American Oil Chemists' Society》1999,76(8):921-925
The effects of 0, 250, 500, and 1000 ppm (wt/vol) ascorbyl palmitate (AP) on the gamma irradiation-induced oxidation of soybean
oil, cottonseed oil, corn oil, tallow, lard, or linoleic acid either in a solvent mixture (benzene/methanol, 4:1 vol/vol)
or in methanol, was studied immediately after gamma irradiation with a dose of 1–5 kGy. Steady-state kinetic approximation
was used to determine a quenching mechanism and quenching rate constant of AP on the gamma irradiation-induced oxidation of
purified soybean oil in a solvent mixture (benzene/methanol, 4:1 vol/vol). Irradiation greatly increased oxidation of all
oils, as was expected. AP was extremely effective at minimizing oxidation in all oils, and its effectiveness was concentration
dependent. AP showed significantly greater antioxidative activity than α-tocopherol for the reduction of oxidation in all
oils (P<0.05). The steady-state kinetic studies indicated that AP quenched oxygen only to minimize the oxidation of oils. The calculated
total quenching rate of AP was 7.51×107 M−1s−1. The present results clearly show the effective oxygen quenching ability of AP for the reduction of gamma irradiation-induced
oxidation of oils. 相似文献
2.
Effects of quenching mechanisms of carotenoids on the photosensitized oxidation of soybean oil 总被引:2,自引:0,他引:2
The effects of 0, 1.0 × 10”−5, 2.5 × 10−5, and 5.0 × 10−5 M β-apo-8'-carotenal, β-carotene, and canthaxanthin on the photooxidation of soybean oil in methylene chloride containing
3.3 × 10−9 M chlorophyll b were studied by measuring peroxide values and conjugated diene content. β-Apo-8'-carotenal, β-carotene, and
canthaxanthin contain 10,11, and 13 conjugated double bonds, respectively. The peroxide values and conjugated diene contents
of oils containing the carotenoids were significantly lower (P<0.05) than those of control oil containing no carotenoid. As
the number of conjugated double bonds of the carotenoids increased, the peroxide values of soybean oils decreased significantly
(P<0.05). The quenching mechanisms and kinetics of the carotenoids in the photosensitized oxidation of soybean oil were studied
by measuring peroxide values. The steady-state kinetics study showed that carotenoids quenched singlet oxygen to reduce chlorophyll-sensitized
photooxidation of soybean oil. The singlet-oxygen quenching rate constants ofβ- apo-8'-carotenal, β-carotene, and canthaxanthin were 3.06 × 109, 4.60 × 109, and 1.12 × 1010 M−1sec−1, respectively. 相似文献
3.
Monica M. Neumann Silvia N. Fusero Norman A. García 《Journal of the American Oil Chemists' Society》1991,68(9):662-665
The susceptibilities of crude soybean, sunflower and peanut oils to singlet oxygen photooxidation were determined in a kinetic
study. The accumulation of photosensitized hydroperoxides, determined spectroscopically, and the quenching of singlet molecular
oxygen phosphorescence by the crude oils and their fatty acid methyl esters were compared.
The relative tendency to photooxidation for the oils and the methyl esters was soybean ≫ sunflower > peanut. This trend was
independent of the method employed in the determination of initial photodamaging.
Soybean oil was demonstrated to be the most unstable product, not only due to the presence of highly unsaturated fatty acids,
but also due to the absence of natural constituents, capable of providing a protective antioxidant effect. This protection
was more effective in sunflower and peanut oils. 相似文献
4.
A. H. Clements R. H. Van Den Engh D. J. Frost K. Hoogenhout J. R. Nooi 《Journal of the American Oil Chemists' Society》1973,50(8):325-330
Sensitized photooxidation of a model 1,4-diene, 4cis, 7cis-undecadiene, was shown to yield 4-hydroperoxy-5trans,7cis-undecadiene and 5-hydroperoxy-3trans,7cis-undecadiene as initial products. Further irradiation (in the presence of the sensitizer) caused the isomerization of 4-hydroperoxy-5trans,7cis-undecadiene to 4-hydroperoxy-5trans,7trans-undecadiene. Oxidation of 4cis,7cis-undecadiene with chemically formed singlet oxygen gave the same initial products as the photosensitized oxidation. 5-Hydroperoxy-3trans,7cis-undecadiene is, however, not formed in the radical autoxidation of the diene. It is concluded that singlet oxygen is the
reactive intermediate in the photooxidation. Comparison with this model reaction suggests that the photooxidation of refined
soybean oil in propanol also proceeds via singlet oxygen: the photooxidations of both 4,7-undecadiene and soybean oil are
inhibited by β-carotene and by triethylamine, but unlike radical chain autoxidation, they are not inhibited by 2,6-di-t-butyl-4-methylphenol. Also soybean oil can act as a sensitizer for the photooxidation of 4,7-undecadiene. Chlorophyl-like
sensitizers are probably unimportant in the well refined soybean oil used in this work. The observed photooxidation of the
skipped dienoic components of soybean oil, which is probably due to some other, unidentified sensitizer(s), absorbing below
500 nm, can be avoided by using a yellow filter.
Presented in part in the symposium “Oxidation Chemistry,” New Chemical Society Meeting, Manchester, April 1972. 相似文献
5.
M. Tasioula-Margari G. Márquez-Ruíz M. C. Dobarganes 《Journal of the American Oil Chemists' Society》1996,73(11):1579-1584
Precipitates enriched in oligomeric triacylglycerides were separated from thermally oxidized olive residue oil, conventional
and high-oleic sunflower oils, and soybean oil by solvent fractionation in methanol/acetone at 4–5°C for 16 h. Different fractionation
conditions were evaluated in an effort to isolate the oligomeric triacylglycerides (OTG). OTG, formed in frying oils upon
heating at low concentations, were not detectable with conventional methods to determine polymeric compounds. The best conditions
found from the different assays were the following: (i) weight of oil sample-to-solvent volume ratio of 1∶20; and (ii) solvent
system methanol/acetone 10∶90 (vol/vol) for monounsaturated oils and 15∶85 (vol/vol) for polyunsaturated oils. Precipitates,
enriched in oligomers, were formed when heated oils and used frying oils contained more than 27% polar compounds, a value
which is widely accepted as the upper limit for use of frying oils. 相似文献
6.
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
7.
The role of singlet oxygen in oxidation was studied by analyzing hydroperoxide isomers in unsaturated fats and esters by gas
chromatography-mass spectrometry (GC-MS). On oxidation photosensitized with methylene blue at 0 C, methyl oleate produced
a 50–50% mixture of 9- and 10-hydroperoxides, linoleate a mixture of 66% conjugated (9+13) and 34% unconjugated (10+12) hydroperoxides,
and linolenate a mixture of 75% conjugated (9+12+13+16) and 25% unconjugated (10+15) hydroperoxides. Cottonseed, safflower,
and corn oil esters showed, as in soybean esters, the presence of varying amounts of 12-hydroxy esters derived from the corresponding
hydroperoxide at low peroxide values. Since these oils do not contain linolenic acid, a likely source of the 12-hydroperoxide
is linoleic acid by photosensitized oxidation. Several lines of evidence support the conclusion that singlet oxygen may contribute
to the unique hydroperoxide composition of vegetable oil esters at low levels of oxidation. In the presence of photosensitizers
such as methylene blue and chlorophyll, the unique hydroperoxide composition (high levels of 10- and 12-hydroperoxides) obtained
in soybean esters was similar to that produced by oxidation at low peroxide values. In contrast, a normal hydroperoxide composition
was produced, as expected from the fatty acid composition of soybean oil esters, when singlet oxygen quenchers such as β-carotene
and α-tocopherol were used and when the esters were treated with carbon black to remove natural photosensitizers. GC-MS analyses
of the derived unsaturated alcohols provided indirect evidence for 12-hydroperoxy-9,13-diene in soybean esters as expected
by photosensitized oxidation of linoleate.
Presented at the AOCS Meeting, San Francisco, California, April 29–May 3, 1979.
The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of
Agriculture over other firms or similar products not mentioned. 相似文献
8.
Young Woo Park Min Kyu Jeong ChanUk Park JaeHwan Lee 《Journal of the American Oil Chemists' Society》2011,88(3):373-380
Profiles of triacylglycerols (TAG) and fatty acids were compared in soybean oil thermally oxidized at 180 °C for 60 min or
methylene blue photosensitized for 10 h. Headspace oxygen in thermally oxidized and photosensitized soybean oil decreased
significantly (p < 0.05) as oxidation time increased. Relative contents of linoleic and linolenic acids decreased and those of oleic acid
increased during oxidation. In both thermal and photosensitized oxidation, TAG with lower than 44 equivalent carbon number
including dilinoleoyllinolenoylglycerol (LLLn, 40), trilinolein (LLL, 42), oleoyllinoleoyllinolenoylglycerol (OLLn, 42), dilinoleoyloleoylglycerol
(LLO, 44), and dilinoleoylpalmitoylglycerol (PLL, 44) significantly decreased, while those with dioleoyllinoleoylglycerol
(OOL, 46) increased significantly in relative peak areas (p < 0.05). Photosensitized oxidation decreased TAG containing linoleic and linolenic acids significantly faster than thermal
oxidation in soybean oil (p < 0.05), which may be due to the singlet oxygen reaction. Photosensitized soybean oils can be differentiated from thermally
oxidized samples using the distributions of TAG by principal component analysis. 相似文献
9.
Simultaneous determination of ascorbyl palmitate and nine phenolic antioxidants in vegetable oils and edible fats by HPLC 总被引:1,自引:0,他引:1
This study describes an HPLC method for the simultaneous determination of ascorbyl palmitate (AP) and synthetic phenolic antioxidants
(SPA) in vegetable oils and edible fats in a single run. To achieve this, citric acid was used in combination with isoascorbic
acid for stabilization of AP in standard and sample solutions and for deactivation of oxidizing agents in the HPLC system.
SPA and AP were directly extracted from samples with methanol containing 1 mg/mL each of citric acid and isoascorbic acid.
HPLC analytical and guard columns were pretreated with 90% methanol/acetonitrile 1∶1 (vol/vol), containing 4 mg/mL each of
citric acid and isoascorbic acid, and 10% water at pH 3, for 30 min. Under these conditions, AP was stable for about 7 h at
room temperature. The relative SD of repeatability for AP (0.5–3.6%) was comparable to that for SPA (0.3–2.8%). Average recovery
from spiked samples was 100% for AP, 98–103% for SPA, and 85% for BHT (up to 90% using double extraction with methanol). 相似文献
10.
Use of high-resolution 13C nuclear magnetic resonance spectroscopy for the screening of virgin olive oils 总被引:2,自引:0,他引:2
Rosario Zamora Virginia Alba Francisco J. Hidalgo 《Journal of the American Oil Chemists' Society》2001,78(1):89-94
13C Nuclear magnetic resonance (NMR) spectra of 104 oil samples were obtained and analyzed in order to study the use of this
technique for routine screening of virgin olive oils. The oils studied included the following: virgin olive oils from different
cultivars and regions of Europe and north Africa, and refined olive, “lampante” olive, refined olive pomace, high-oleic sunflower,
hazelnut, sunflower, corn, soybean, rapeseed, grapeseed, and peanut oils, as well as mixtures of virgin olive oils from different
geographical origins and mixtures of 5–50% hazelnut oil in virgin olive oil. The analysis of the spectra allowed us to distinguish
among virgin olive oils, oils with a high content of oleic acid, and oils with a high content of linoleic acid, by using stepwise
discriminant analysis. This parametric method gave 97.1% correct validated classifications for the oils. In addition, it classified
correctly all the hazelnut oil samples and the mixtures of hazelnut oil in virgin olive oil assayed. All of these results
suggested that 13C NMR may be used satisfactorily for discriminating some specific groups of oils, but to obtain 100% correct classifications
for the different oils and mixtures, more information than that obtained from the direct spectra of the oils is needed. 相似文献
11.
This study was part of a larger experiment designed to assess the vitamin E adequacy of corn and soybean oils in relation
to their polyunsaturated fatty acids (PUFA). Young male rats were fed a semipurified diet containing 20% corn or soybean oil
and adequate selenium. After 8 and 12 weeks, animals were sacrificed, and 7 tissues analyzed for α- and γ-tocopherols and
for fatty acids. Calculations were made of the molar ratios of total polyunsaturated fatty acids/α-tocopherol, and also of
all polyunsaturated fatty acids, except linoleate, designated polyunsaturated fatty acids>18∶2, to α-tocopherol. It is proposed
that the latter ratio may have more significance, physiologically, than when linoleic acid also is considered. Tissues from
rats fed corn oil had slightly more favorable (lower) ratios than did tissues from rats fed soybean oil. In both groups, the
molar polyunsaturated fatty acids>18∶2/α-tocopherol ratio was lowest for heart and lung, intermediate for muscle and testis,
and highest for liver, kidney, and adipose tissue. Since both corn and soybean oils provide adequate vitamin E as determined
by several biochemical and physiological parameters, adequate molar ratios of polyunsaturated fatty acids>18∶2/α-tocopherol
were: lung, 400; heart and leg muscles, 700; testis, 1100; liver and kidney, 1500–2000; and adipose tissue, 2000. 相似文献
12.
Lennart Svensson 《Lipids》1983,18(3):171-178
The influence of dietary partially hydrogenated marine oils on distribution of phospholipid fatty acids in rat liver microsomes
was studied with particular reference to the metabolism of linoleic acid. Five groups of weanling rats were fed diets containing
20% (w/w) peanut oil (PO), partially hydrogenated peanut oil (HPO), partially hydrogenated Norwegian capelin oil (HCO), partially
hydrogenated herring oil (HHO), and rapeseed oil (RSO) for 10 weeks. The partially hydrogenated oils were supplemented with
linoleic acid corresponding to 4.6 cal % in the diets. Accumulation of linoleic acid and reduced amount of total linoleic
acid metabolites were observed in liver microsomal phospholipids from rats fed partially hydrogenated oils as compared to
PO feeding. The most striking effects on the distribution of ω6-polyunsaturated fatty acids was obtained after feeding HHO,
a marine oil with a moderate content oftrans fatty acids in comparison with HPO but rich in isomers of eicosenoic and docosenoic acids. Liver microsomal Δ6-as well as Δ6-desaturase activities as measured in vitro were reduced in rats kept on HHO as compared to PO dietary treatment. The results
obtained suggest that the dietary influence of partially hydrogenated marine oils on the metabolism of linoleic acid might
be better related to the intake of isomeric eicosenoic and docosenoic acids than to the total intake oftrans fatty acids. 相似文献
13.
In the present study we have used statistical experimental design and multivariate optimization to formally optimize a reversed-phase
high-performance liquid chromatography method for the analysis of triacylglycerol molecular species of natural oils. The optimal
conditions found were, on an octadecylsilan-column, from acetonitrile/isooctane (90∶10, vol/vol) to acetonitrile/ethanol/isooctane
(40∶35∶25, by vol), at a column temperature of 50°C and a flowrate of 1.5mL/min using a negative exponential gradient profile.
Several examples of separations of natural seed and animal oils,i.e., soybean oil, rapeseed oil, palm oil, linseed oil, tallow and fish oil, are given. A version of the equivalent carbon number
concept, utilizing the Snyder polarity index, was used to identity the molecular species. 相似文献
14.
Virgin olive oil was photooxidized at 2 and 40°C and at fluorescent light intensities of 0, 620, 2710, and 5340 lux. As expected,
higher fluorescent light intensities induced higher peroxide formation in the oil. The thiobarbituric acid reactive substances
(TBARS) were found to be good indicators of photooxidation during the early stage of the reaction. Pheophytin A and β-carotene
were light- and temperature-sensitive, whereas α-tocopherol and total polyphenols were mostly affected by light. Pheophytin
A functioned as a photosensitizer, resulting in rapid oxidation of the oil. β-Carotene was a strong natural inhibitor of photooxidation
for all light intensities at 2°C, suggesting quenching properties for singlet oxygen. However, β-carotene antioxidant activity
was reduced at 40°C because of its rapid destruction. 相似文献
15.
Yong Wang Mouming Zhao Shuze Tang Keke Song Xue Han Shiyi Ou 《Journal of the American Oil Chemists' Society》2010,87(5):483-491
The oxidative stability of diacylglycerol (DAG)-enriched soybean oil and palm olein produced by partial hydrolysis using phospholipase
A1 (Lecitase Ultra) and molecular distillation was investigated at 110 °C by the Rancimat method with and without addition
of synthetic antioxidants. Compared with triacylglycerol oils, the DAG-enriched oils displayed lower oxidative stability due
to a higher content of unsaturated fatty acids and a lower level of tocopherols. With the addition (50–200 mg/kg) of tert-butylhydroquinone (TBHQ) or ascorbyl palmitate (AP), the oxidative stability indicated by induction period (IP) of these
DAG-enriched oils under the Rancimat conditions was improved. The IP of the diacylglycerol-enriched soybean oil increased
from 4.21 ± 0.09 to 12.64 ± 0.42 h when 200 mg/kg of TBHQ was added, whereas the IP of the diacylglycerol-enriched palm olein
increased from 5.35 ± 0.21 to 16.24 ± 0.55 h when the same level of AP was added. Addition of TBHQ, alone and in combination
with AP resulted in a significant (p ≤ 0.05) increase in oxidative stability of diacylglycerol-enriched soybean oil. AP had a positive synergistic effect when
used with TBHQ. 相似文献
16.
Nongnuch Sutivisedsak Bryan R. Moser Brajendra K. Sharma Roque L. Evangelista Huai N. Cheng William C. Lesch Robert R. Tangsrud Atanu Biswas 《Journal of the American Oil Chemists' Society》2011,88(2):193-200
Four common beans (black, kidney, great northern, and pinto) were extracted with hexane and found to contain about 2% triacylglycerols.
The fatty acids in these bean oils were mainly linolenic (41.7–46 wt%), linoleic (24.1–33.4 wt%), palmitic (10.7–12.7 wt%)
and oleic (5.2–9.5 wt%). Because of the high levels of polyunsaturated fatty acids, the bean oils had iodine values between
174 and 177 g/100 g (compared to 130 g/100 g for soybean oil). Yet, the bean oils exhibited high oxidative stability due to
the presence of high amounts of tocopherols (2,670–2,970 ppm). The bean oils had lower pour points (−18 to −11 °C) compared
to −9 °C for soybean oil. Among the four bean oils, kidney bean oil had the highest acid value (15.4 mg KOH/g) and kinematic
viscosities over a wide range of temperatures. 相似文献
17.
The aim of the present study was to investigate the influence of partially hydrogenated vegetable and marine oils on membrane
composition and function of liver microsomes and platelets with particular reference to the metabolism of linoleic acid and
the production of arachidonic acid metabolites. Four groups of male weanling rats were fed linoleic acid supplemented diets
containing 20% (w/w) of partially hydrogenated low erucic acid rapeseed oil (HLRSO), partially hydrogenated herring oil (HHO),
olive oil (OO) and trierucin + triolein (TE) for 10 weeks. An additional two groups were fed partially hydrogenated low erucic
acid rapeseed oil and partially hydrogenated herring oil without linoleic acid supplementation (HLRSO- and HHO-, respectively).
Substantial amounts oftrans fatty acids were incorporated into liver microsomes (12.6% in group HLRSO) and platelets (7.0% in group HLRSO-). This incorporation
was not dependent on the dietary linoleic acid level. Hepatic microsomal Δ5-desaturase activity was significantly increased after HLRSO feeding compared to OO feeding. Δ6-Desaturase activity did not vary in the linoleic acid supplemented groups. Both Δ5- and Δ6-desaturase activities were significantly increased in groups without linoleic acid supplementation.
Docosenoic acid was incorporated into platelet phospholipids in contrast to liver microsomes. In the platelet, docosenoic
acid seemed to have a special preference for phosphatidylserine. Very small amounts were incorporated into platelet phosphatidylinositol.
Feeding diets HLRSO, HHO and OO did not influence rat platelet cyclooxygenase or 12-lipoxygenase activity. Platelets from
rats fed TE, however, produced significantly less 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) than platelets from
rats fed OO. Feeding of HLRSO- and HHO- resulted in a significantly diminished production of the arachidonic acid metabolites
12-HETE, 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and 6-keto-prostaglandin F1α in stimulated platelets and aorta. Thus, high dietary levels oftrans isomers of monoenoic acids do not interfere with platelet cyclooxygenase or lipoxygenase activity provided sufficient amounts
of linoleic acid are available. 相似文献
18.
Susana Criado Norman A. García Maria I. Gutirrez Vicente Avila Sonia G. Bertolotti Rio Cuarto 《European Journal of Lipid Science and Technology》1996,98(5):172-175
The ability of mono-, di-, tri-and tetra-hydroxyflavones (7-and 3-hy-droxyflavones, 7, 8-dihydroxyflavone, baicalein and fisetin) to act as photoprotectors against singlet molecular oxygen [O2(Δg)]-initiated photooxidation of fats has been established by a kinetic study. The overall quenching rate constants for a series of five hydroxyflavones perfectly parallel their respective behaviour as inhibitors of the sensitized photooxidation of linoleic acid. The best antioxidative effect was exerted by 7-hydroxyflavone which does not chemically react with O2(1Δg). Nevertheless for the remaining flavonoids of the series, the physical deactivation of O2(1Δg) largely prevails over the chemical process. As for the cases of phenols and related hydroxy-aromatic derivatives, the ionization of the -OH group in the flavones, dramatically accelerates the rate of photooxidation. Under these conditions, the 7-hydroxyflavone also reacts effectively with O2(1Δg). Given that flavonoids are natural oil components, this medium effect should be taken into account during the oil-refining process, in order to avoid the flavonoid photodestruction. 相似文献
19.
Male Wistar rats were fed semipurified diets containing 20% fat for 25 weeks. Ten different oils or oil blends were employed,
including rapeseed oils, simulated rapeseed-type oils, and modified rapeseed-type oils. Safflower, soybean, and hydrogenated
coconut oils served as control oils. Histopathological examination of the cardiac tissue was conducted at the end of the study
and an incidence-severity rating assigned to the lesions induced by each fat. Oils containing high levels of erucic acid (26–30%)
induced the most severe cardiac necrosis, irrespective of the source of erucic acid (rapeseed oil or nasturtium oil). Increasing
the linoleic: linolenic acid ratio of the high erucic oils to that of soybean oil failed to reduce necrosis, but the absence
of linolenic acid from a high erucic acid oil blend resulted in a markedly reduced lesion incidence-severity rating, comparable
to those obtained for low erucic acid rapessed oil and soybean oil which were similar. Lowest lesion incidence was obtained
with safflower oil and hydrogenated coconut oil. We have postulated that linolenic acid plays a role in the etiology of cardiac
necrosis observed when rats are fed diets containing low erucic acid rapeseed oils. 相似文献
20.
Partially hydrogenated marine oils containing 18∶1-, 20∶1- and 22∶1-isomers and partially hydrogenated peanut oil containing
18∶1-isomers were fed as 24–28 wt % of the diet with or without supplement of linoleic acid. Reference groups were fed peanut,
soybean, or rapeseed oils with low or high erucic acid content. Dietary monoene isomers reduced the conversion of linoleic
acid into arachidonic acid and the deposition of the latter in liver and heart phosphatidylcholine. This effect was more pronounced
for the partially hydrogenated marine oils than for the partially hydrogenated peanut oil. The content oftrans fatty acids in liver phospholipids was similar in groups fed partially hydrogenated fats. The distribution of various phospholipids
in heart and liver was unaffected by the dietary fat. The decrease in deposition of arachidonic acid in rats fed partially
hydrogenated marine oils was shown in vitro to be a consequence of lower Δ6-desaturase activity rather than an increase in
the peroxisomal β-oxidation of arachidonic acid. The lower amounts of arachidonic acid deposited may be a result of competition
in the Δ6-desaturation not only from the C22-and C20-monoenoic fatty acids originally present in the partially hydrogenated
marine oil, but also from C18- and C16-monoenes produced by peroxisomal β-oxidation of the long-chain fatty acids.
Part of this work was presented at the ISF-AOCS Congress, New York City, 1980. 相似文献