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1.
The low temperature crystallization technique for the enrichment of “minor” components, such as sterols and sterol esters,
from vegetable oils was applied to low erucic acid rapeseed oils. The recovery of free sterols and sterol esters was estimated
by use of14C-cholesterol and14C-cholesterol oleate. 80% of the free sterols and 45% of the sterol esters were recovered in the liquid fraction, while in
two studies total recoveries were 95% and 99%, respectively. This technique showed some selectivity toward the sterol bound
fatty acids when compared to direct preparative thin layer chromatography (TLC) of the crude oil. Gas liquid chromatography
(GLC) analysis of the free and esterified sterols as TMS-derivatives showed very little selectivity in the enrichment procedure.
The fatty acid patterns of the sterol esters demonstrated, however, a preference in the liquid fraction for those sterol esters
which have a high linoleic and linolenic acid content. The content of free sterols was 0.3–0.4% and that of sterol esters
0.7–1.2% of the rapeseed oils in both winter and summer types of low erucic acid rapeseed (Brassica napus) when the lipid classes were isolated by direct preparative TLC of the oils. The free sterols in the seven cultivars or breeding
lines analyzed were composed of 44–55% sitosterol, 27–36% campesterol, 17–21% brassicasterol, and a trace of cholesterol.
The esterified sterols were 47–57% sitosterol, 36–44% campesterol, 6–9% brassicasterol, and traces of cholesterol and Δ5-avenasterol.
The fatty acid patterns of these esters were characterized by ca. 30% oleic acid and ca. 50% linoleic acid, whereas these
acids constitute 60% and 20%, respectively, of the total fatty acids in the oil. Little or no variation in sterol and sterol
ester patterns with locality within Sweden was observed for the one cultivar of summer rapeseed investigated by the low temperature
crystallization technique. 相似文献
2.
Daniel R. Muchiri Symon M. Mahungu Simon N. Gituanja 《Journal of the American Oil Chemists' Society》2012,89(9):1567-1575
Four varieties (Boribo, Dodo, Kagege, and Kent) of ripe mango (Mangifera indica, L.) fruits were collected directly from the farmers in Meru County (Kenya), peeled, depulped and the stones deshelled. The mango kernels obtained were crushed, sun-dried, and extracted using petroleum ether (b.p. 40–60 °C). The fat content of the mango kernels varied from 8.5 to 10.4 % depending on the variety. The mango seed kernels constituted about (4.76–6.70 %) crude protein (Nx6.25), (1.74–2.26 %) crude ash, (71.90–76.28 %) crude carbohydrate, (1743–1782 kJ) gross energy, (1547–1576 kJ) available energy, and mean protein:energy ratios of (2.63–3.76 mg/kJ) all on a moisture free basis. The moisture content of fresh mango seed kernels varied from 42.1 to 67.6 % depending on the variety. The fat had a melting point of 25–33 °C, an iodine value of 51.08–56.79, an acid value of 4.49–7.48, free fatty acid (as oleic) of 2.26–3.76, a saponification number of 188.8–195.9, unsaponifiable matter of 2.26–2.74 %, a peroxide value of 0.40–0.75, a refractive index(40 °C) of 1.4562–1.4597 and a specific gravity of 0.9017–0.9087. Investigation of the fatty acid composition revealed(GLC) nine fatty acids: tetradecanoic acid (trace-0.05 %), pentadecanoic acid (trace–0.09 %), hexadecanoic acid (4.87–10.57 %), heptadecanoic acid (trace-O.10 %), octadecanoic acid (24.22–32.80 %), 9-(Z)-octadecenoic acid (46.37–58.59 %), 9-(Z), 12-(Z)-octadecadienoic acid (6.73–10.35 %), 9-(Z), 12-(Z), 15-(Z)-octadecatrienoic acid (0.601–1.8 %), and eicosanoic acid (0.62–1.64 %). The fat had the typical characteristics of a vegetable butter. 相似文献
3.
Flour samples were prepared from intact and degermed kernels of Hard Red Spring, Soft White Spring, and Amber Durum wheats.
The “free” (hexane soluble) and “bound” (hexane resistant, water-saturatedn-butanol extractable) lipids were extracted from the six flours and separated quantitatively by silicic acid column chromatography.
Thin-layer chromatography (TLC) was used to monitor the column and to resolve the lipid classes into components. Gas-liquid
chromatography (GLC) was used to obtain the fatty acid composition of the triglyceride, sterol ester, and phospholipid fractions,
and also to determine the nature of the sterol components of the unesterified sterol and sterol ester classes.
Similar patterns of lipid classes were shown by all three varieties; the differences were in the degree of dominance. In fatty
acid composition some varietal differences were found but the greatest difference was between lipid classes.
Contribution No. 5 of the Food Research Institute. Presented at the AOCS Meeting, Toronto, 1962. 相似文献
4.
Emile M. Gaydou Philippe Bouchet 《Journal of the American Oil Chemists' Society》1984,61(10):1589-1593
The kernel fat content of 16 different mango varieties collected from the Northwestern part of Madagascar island were examined.
The fat content (22–54%) was determined by chloroform/methanol extraction. Investigation by gas liquid chromatography (GLC)
revealed 15 fatty acids, mainly palmitic (7–12%), stearic (22–40%), oleic (41–48%) and linoleic (7–17%). Significant correlations
were observed among the main fatty acids. Testing for the sterol fraction in 15 mango varieties allowed us to separate and
quantitatively analyze 7 sterols by GLC. The main sterols wereβ-sitosterol (47–76%), stigmasterol (12–23%) and campesterol (7–12%). The stigmasterol/campesterol ratio (1.2:2.3) was lower
in mango kernel fat than in cocoa butter. Among the 4-methyl sterol fractions, gramisterol, lophenol, obtusifoliol and citrostadienol
were tentatively identified by GLC. Lupeol, cycloartenol,α- andβ-amyrins and friedelinol were tentatively identified by GLC in the triterpene alcohols fractions. 相似文献
5.
E. M. Gaydou R. Raonizafinimanana J. P. Bianchini 《Journal of the American Oil Chemists' Society》1980,57(4):141-142
The fatty acid and sterol compositions of six Malagasy rice bran oils were evaluated. Investigation by gas liquid chromatography
(GLC) using Carbowax 20 M revealed 10 fatty acids, mainly palmitic (16–20%) oleic (41–44%) and linolenic (31–37%) acids. An
OV 17 column was used to separate eight sterols, mainly Β-sitosterol (53–59%), campesterol (16–26%) and stigmasterol (10–13%).
No significant variation for the fatty acid and sterol contents was observed among the rice varieties studied. 相似文献
6.
The lipid classes, fatty acids of total and individual lipids and sterols of Antarctic krill (Euphausia superba Dana) from two areas of the Antarctic Ocean were analyzed by thin layer chromatography (TLC), gas liquid chromatography (GLC)
and gas liquid chromatography/mass spectrometry (GLC/MS). Basic differences in the lipid composition of krill from the Scotia
Sea (caught in Dec. 1977) and krill from the Gerlache Strait (caught in Mar. 1981) were not observed. The main lipid classes
found were: phosphatidylcholine (PC) (33–36%), phosphatidylethanolamine (PE) (5–6%), triacylglycerol (TG) (33–40%), free fatty
acids (FFA) (8–16%) and sterols (1.4–1.7%). Wax esters and sterol esters were present only in traces. More than 50 fatty acids
could be identified using GLC/MS, the major ones being 14∶0, 16∶0, 16∶1(n−7), 18∶1(n−9), 18∶1(n−7), 20∶5(n−3) and 22∶6(n−3).
Phytanic acid was found in a concentration of 3% of total fatty acids. Short, medium-chain and hydroxy fatty acids (C≤10)
were not detectable. The sterol fraction consisted of cholesterol, desmosterol and 22-dehydrocholesterol. 相似文献
7.
Afaf Kamal-Eldin Lars Åke Appelqvist 《Journal of the American Oil Chemists' Society》1994,71(2):135-139
Seeds from different collections of cultivatedSesamum indicum Linn. and three related wild species [specifically,S. alatum Thonn.,S. radiatum Schum and Thonn. andS. angustifolium (Oliv.) Engl.] were studied for their oil content and fatty acid composition of the total lipids. The wild seeds contained
less oil (ca. 30%) than the cultivated seeds (ca. 50%). Lipids from all four species were comparable in their total fatty acid composition, with palmitic (8.2–12.7%), stearic
(5.6–9.1%), oleic (33.4–46.9%) and linoleic acid (33.2–48.4%) as the major acids. The total lipids from selected samples were
fractionated by thin-layer chromatography into five fractions: triacylglycerols (TAG; 80.3–88.9%), diacylglycerols (DAG; 6.5–10.4%),
free fatty acids (FFA; 1.2–5.1%), polar lipids (PL; 2.3–3.5%) and steryl esters (SE; 0.3–0.6%). Compared to the TAG, the four
other fractions (viz, DAG, FFA, PL and SE) were generally characterized by higher percentages of saturated acids, notably palmitic and stearic
acids, and lower percentages of linoleic and oleic acids in all species. Slightly higher percentages of long-chain fatty acids
(20∶0, 20∶1, 22∶0 and 24∶0) were observed for lipid classes other than TAG in all four species. Based on the fatty acid composition
of the total lipids and of the different acyl lipid classes, it seems thatS. radiatum andS. angustifolium are more related to each other than they are to the other two species. 相似文献
8.
cis-Vaccenic acid in mango pulp lipids 总被引:1,自引:3,他引:1
A peak corresponding to a methyl octadecenoate other than oleate has been detected on the capillary gas chromatogram of the
methyl esters of mango pulp fatty acids. This octadecenoate was isolated by silica gel and argentation column chromatography,
high performance liquid chromatography and argentation thin layer chromatography, and then analyzed by infrared, nuclear magnetic
resonance and gas chromatography-mass spectrometry, chromatographic separations and oxidative degradation. These analytical
data proved that the octadecenoic acid wascis-vaccenic acid (cis-11-octadecenoic acid). The concentration of this acid in total octadecenoic acids ranged from 35% to 50% in the pulp of mangoes
from Fiji, Mexico, the Philippines and Taiwan.cis-Vaccenic acid was revealed to be one of the major component fatty acids of non-polar lipids (mainly triacylglycerols), glycolipids
and phospholipids in mango pulp. The glycolipids containedcis-vaccenic acid (ca. 20%) in higher concentration than oleic acid (ca. 15%). A trace amount ofcis-vaccenic acid (0.5%) was detected in the total lipids of mango seeds. Profile of fatty acid composition of mango pulp lipids
(0.2–0.3 wt% of wet pulp) was characterized by the presence of n−7 acid isomers,cis-vaccenic acid and palmitoleic acid, and unusual mono- and dienoic positional isomers. 相似文献
9.
A. S. Kulkarni R. R. Khotpal H. A. Bhakara 《Journal of the American Oil Chemists' Society》1991,68(11):891-893
Studies on the glycolipid compositions of Kenaf, English walnut, Myrobalan and Manila tamarind seeds found in the Vidarbha
region of Central India have been carried out by silicic acid column chromatography and thin-layer chromatography (TLC). The
total glycolipids have been separated into individual components such as monogalactosyldiglycerides 20–28%, digalactosyldiglycerides
40–41%, sterylgalactosides 15–18%, acylated sterylgalactosides 8–15% and unidentified components 0.8–2%. The fatty acid composition
of total and component glycolipids as determined by gas-liquid chromatography (GLC) showed the predominant fatty acids to
be palmitic, stearic and oleic acids. Sugar in the component glycolipids was found to be exclusively galactose. 相似文献
10.
M. H. El Abd Aal E. G. Gomaa H. A. Karara 《European Journal of Lipid Science and Technology》1987,89(8):304-306
The chemical composition of bitter almond, plum and mango kernels and the physico-chemical characteristics of their lipids were studied. Bitter almond and plum kernels contained higher amounts of lipids in comparison to mango kernels. All kernel lipids were found free from hydrocyanic acid. The predominant lipid class of the studied kernel lipids was triglycerides. Oleic acid was the major fatty acid present in bitter almond and plum kernel lipids, while mango kernel lipids were rich in stearic and oleic acid. 相似文献
11.
C. Yvonne Shuster J. R. Fronines H. S. Olcott 《Journal of the American Oil Chemists' Society》1964,41(1):36-41
The composition of the lipids from the white muscle of five tuna fish has been determined. Total extractable lipid varied
from 0.5%–10.3% of the tissue wet weight; phospholipid content ranged from 0.3%–0.6%. The separation of the phospholipid components
was made by column chromatography with activated silicic acid and stepwise elution, with increasing concentrations of methanol
in chloroform. The components were identified by chemical tests and infrared (IR) spectra. Tuna white musele contained an
average of 0.5% phospholipid on wet weight basis; 23% was cephalin, 54% lecithin, 8% sphingomyelin, 2% phosphoinositide, with
small amounts of unidentified components. Ten to 30% of the lecithin and cephalin fractions were in the form of plasmalogens.
The gas-liquid chromatographic analyses of the 12–22 carbon fatty acids of the lecithin, cephalin, and neutral fractions are
presented. The cephalins were characteristically high in stearie acid and low in palmitic acid, in contrast to the lecithins. 相似文献
12.
Fatty acid composition and its relationship with physicochemical properties of pecan (Carya illinoensis) oil 总被引:1,自引:0,他引:1
J. F. Toro-Vazquez M. A. Charó-Alonso F. Pérez-Briceño 《Journal of the American Oil Chemists' Society》1999,76(8):957-965
The composition and physicochemical properties of pecan (Carya illinoensis) kernels and oils from different native trees of the central region of Mexico were investigated. The main compositional characteristic
of the kernel was the high lipid content (70–79% w/w on dry basis) with elevated concentration of oleic acid (55–75% w/w).
The results confirmed the relationship in the biosynthesis of linoleic and linolenic acids from oleic acid existing in oilseeds.
Our results indicate that in pecans such relationship is a function of pecan tree age. The proportion of oleic, linoleic,
and linolenic fatty acids determined the oxidative stability, viscosity, and melting/crystallization behavior of pecan oil.
In general, these properties in pecan oils were similar or superior to extra-virgin olive oil and unrefined sesame oil. Although
all native pecan oils studied showed a significant concentration of oleic acid, a particular group of native Mexican pecan
trees produces an oil with a fatty acid composition with the nutritional appeal that consumers demand nowadays (i.e., very
high oleic acid, 60–75%), with excellent natural oxidative stability (i.e., induction time for oxidation between 8.5 and 10.8
h), and substantially higher concentrations of α-, γ-, and δ-tocopherol than in pecan varieties previously reported in the
literature. 相似文献
13.
Paresch Chandra Dutta Seved Helmersson Eshetu Kebedu Getinet Alema Lars-Åke Appelqvist 《Journal of the American Oil Chemists' Society》1994,71(8):839-843
Niger seed samples were collected from different regions in Ethiopia for determination of oil content, and of fatty acid,
tocopherol and sterol composition in the seed oil by gas-liquid chromatography and high-performance liquid chromatography
methods. There was a large variation in oil content, ranging from 29 to 39%. More than 70% of the fatty acids was linoleic
acid (18∶2) in all samples analyzed. The other predominant fatty acids were palmitic (16∶0), stearic (18∶0) and oleic (19∶1)
at a range of 6 to 11% each. Total polar lipids recovered after preparative thin-layer chromatography comprised a small fraction
of the total lipids. They had higher 16∶0 and lower 18∶2 contents than the triacylglycerols.α-Tocopherol was the predominant tocopherol in all samples, 94–96% of the total amounting to 630–800 μg/g oil. More than 40%
of the total sterols wasβ-sitosterol,ca. 2000μg/g oil. The other major sterols were campesterol and stigmasterol, ranging from 11 to 14%. The Δ5- and Δ7-avenasterols were
in the range of 4 to 7%. From the samples studied, no conclusion could be drawn regarding the influence of altitude or location
on oil content, tocopherol and/or sterol contents. The results of the present study on niger seed oil are discussed in comparison
with known data for common oils from Compositae,viz, safflower and sunflower. 相似文献
14.
Soybeans of the Hawkeye variety were picked at eleven periods from 30 to 111 days after flowering and extracted with chloroform-methanol.
The triglyceride fraction of five pickings, selected 35 to 91 days after flowering (when synthesis of lipid was most active),
were isolated by silicic acid thin layer chromatography (TLC) and species composition determined using argentation TLC and
lipase hydrolysis. The triglyceride content of the total lipid increased from 6.5% at 30 days after flowering to 85% in the
mature bean (111 days). The major changes in fatty acid composition of the triglycerides occurred during the first 52 days
after flowering. During this period linolenic acid decreased from 34.2% to 11.7%, the percentages of linoleic and oleic acids
increased, stearic remained fairly constant and palmitic decreased slightly. Large quantitative changes occurred in the molecular
species of the triglycerides of the bean during maturation; some triglycerides containing linolenic acid could not be detected
approximately 66 days after flowering. Although changes occurred in the percentage and amount of each triglyceride species,
the positional distribution of fatty acids remained virtually unchanged throughout maturation. Linolenic acid was distributed
fairly uniformly between the β-position and the α-positions, linoleate favored esterification in the β-position, and oleate
the α-positions. Most of the stearic and palmitic acids were esterified in the α-positions. The consistency of the positional
arrangement of the fatty acids indicated that the mode of glyceride synthesis was established very early during maturation
and molecular species composition was controlled by the fatty acids available for synthesis. 相似文献
15.
Separation of sterol esters from wax esters in the lipids of vernix caseosa and adult human skin surface was accomplished
by column chromatography on MgO. The fatty acids of the sterol esters and wax esters of both samples were separated into saturates
and monoenes, and examined in detail by gas liquid chromatography (GLC). The saturated fatty acids of the wax esters of vernix
caseosa and of adult human skin surface were remarkably similar. They ranged in chain length from at least C11 to C30, six skeletal types being present: straight even, straight odd, iso, anteiso, other monomethyl branched and dimethyl branched.
A large number of patterns of monoenes were observed, each pattern consisting of desaturation of a specific chain at Δ6 or
Δ9 plus its extension or degradation products. The mole per cent of the total Δ6 and Δ9 patterns of wax ester fatty acid monoenes
of vernix caseosa were 87% and 12%, respectively, and 98% and 1%, respectively, for adult human skin surface lipid. The sterol
ester fatty acids of vernix caseosa were much different from those of adult human skin surface: vernix caseosa saturates were
largely branched and of lengths greater than C18, whereas the saturates of adult human surface lipid resembled the wax ester fatty acids. Of the vernix caseosa monoene patterns,
the mole per cent was 30% Δ6 and 70% Δ9, whereas of the adult human skin surface sterol ester fatty acids 89% were Δ6 and
11% Δ9. Chain extension was particularly pronounced in the sterol ester fatty acid monoenes of vernix caseosa amounting to
7–8 C2 units in some cases. The fatty acids of the sterol esters of both vernix caseosa and adult human skin surface appear to be
derived from the sebaceous gland and from the keratinizing epidermis, but those of the wax esters are from the sebaceous glands
only. 相似文献
16.
W. Van Pee L. Boni M. Foma M. Hoylaerts A. Hendrikx 《Journal of the American Oil Chemists' Society》1980,57(8):243-245
Triglycerides of mango seed kernel fat contain, depending on the variety, 32.4–44.0% of stearic acid and 43.7–54.5% of oleic
acid. Palmitic and linoleic acids represent, respectively, 5.9–9.1% and 3.6–6.7% of the fatty acids. The triglycerides also
contain minor amounts of arachidic and linolenic acids. Palmitic, stearic and arachidic acids were almost exclusively distributed
among thesn-1-andsn-3-positions. Oleic acid represented 85–89% of the fatty acids at thesn-2-position. Oleic acid at thesn-1- andsn-3-positions showed a preference for thesn-1-position. Linoleic acid was mainly esterified at thesn-2-position. The amounts of saturated fatty acids, i.e., palmitic and stearic acids, and of oleic acid, at thesn-1- and sn-3-positions, were linearly related to their respective contents in the total triglycerides. 相似文献
17.
The lipids of the common house cricket,Acheta domesticus L., have been examined with the following results. The fatty acids associated with the lipid extracts do not change significantly
from the third through the eleventh week of the crickets' postembryonic life. The major fatty acids are linoleic (30–40%),
oleic (23–27%), palmitic (24–30%), and stearic acids (7–11%). There are smaller amounts of palmitoleic (3–4%), myristic (∼1%),
and linolenic acids (<1%). The fatty acid composition of the cricket lipids reflects but is not identical to the fatty acids
of the dietary lipids: linoleic (53%), oleic (24%), palmitic (15%), stearic (3%), myristic (2%), and linolenic acid (2%).
The amount of triglycerides present in the crickets increases steadily from the second through the seventh or eighth week
of postembryonic life, then drops sharply. Other lipid classes, such as hydrocarbons, simple esters, diglycerides, monoglycerides,
sterols, and free fatty acids remain about constant. The composition of the fatty acids associated with the tri-, di-, and
monoglycerides and the free fatty acid fraction are all about the same. The fatty acids associated with the simple esters
are high in stearic acid.
Postdoctoral Research Associate, Department of Chemistry, University of Michigan, 1965–1967. 相似文献
18.
Fatty acid composition of Iranian citrus seed oils 总被引:1,自引:0,他引:1
Fatty acid compositions of seed oils from eight Iranian citrus fruits were determined. The ranges of values for major fatty
acids were 21.8–29.4% palmitic, 3.1–7.60% stearic, 0.3–1.3% palmitoleic, 23.5–32.3% oleic, 33.5–39.8% linoleic, and 3.1–7.6%
linolenic. Low amounts (up to 0.1%) of myristic and arachidic acids and traces of a few unidentified ones constituted minor
fatty acids. 相似文献
19.
Characterization of the seed oil and meal from apricot,cherry, nectarine,peach and plum 总被引:1,自引:0,他引:1
The oil and meal from apricot, cherry, nectarine, peach and plum seeds were characterized for their physico-chemical properties.
The wt% seed/fruit ranged from 2.8–7.6% and the wt% kernel/seed ranged from 6.8–31.6%. Kernel moisture ranged from 38.8–72.4%.
The proximate composition of whole seeds on a dry weight basis ranged from 1.3–6.9% protein, 0.6–14.5% fat, 51.0–72.3% fiber,
0.4–1.2% ash, and 18.1–27.9% carbohydrate (by difference). The kernels contained 41.9–49.3% fat, and the resulting meals contained
31.7–38.7% protein. The major fatty acids were oleic (52.9–66.3%) and linoleic (26.8%–35.0%). The major essential amino acids
were arginine (21.7–30.5 mmoles/100 g meal) and leucine (16.2–21.6), and the predominant nonessential amino acid was glutamic
acid (49.9–68.0). The iodine values ranged from 105 to 113, hydroxyl value from 5.5 to 7.0 and the unsaponifiables from 0.56–0.80%.
The mineral composition (Cu, Fe, Ca, Mg, Zn, P) was also determined on the meals. 相似文献
20.
The fatty acid composition of oyster larvae at various stages, as well as of the algal diet, were determined by gas liquid
chromatography (GC). Saturated fatty acids are the major fatty acid components in all larval stages and account for 34–62%,
30–35% and 35–81% of the neutral, polar and total lipids of algal-fed larvae respectively. Weight percentage of saturated
fatty acid in “starved” larvae was consistently higher (63–81%) during the whole period. The total polyunsaturated fatty acids
were higher in the polar lipids than in the neutral lipids. The concentration of the ω3 fatty acids also was comparatively
higher in the polar lipids than in the neutral lipids. In the total and neutral lipid fractions, the weight percentage of
polyunsaturated and ω3 fatty acids was higher in the eyed than in the pre-eyed (pediveliger) larvae. Eicosapentaenoic acid
(20∶5ω3) and 22∶6ω3 were not detected in lipids of “starved” and young larvae. There was an accumulation of 20∶5ω3, 22∶6ω3,
and total ω3 fatty acids in the older larvae. Lipid classes were separated by thin layer chromatography (TLC). There was no
qualitative change in lipid composition during larval development, but a marked increased of triacylglycerol in larvae up
to the stage of maturation in algae-fed larvae.
Contribution number 1195 of the Virginia Institute of Marine Science, Gloucester Point, VA 23062 相似文献