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1.
In this study, the contents of total and individual phytosterols in sprouts made from seeds of seven canola (Brassica napus L.) lines (Acropolis, Banjo, Jetton, KS-7740, KSM3-1-124, Mussette and Virginia), grown at three locations in Virginia (Orange, Petersburg and Suffolk), were determined. Canola sprouts contained, on an average, 36.3 g sterols in 100 g of unsaponifiable matter (UNSAP), 10.7 mg sterols in 1 g of oil and 2.4 mg sterols in 1 g of dry sprouts. The contents of individual phytosterols (μg per g of oil) in canola sprouts were 1,162 brassicasterol, 3,799 campesterol, 34 stigmasterol, 5,359 β-sitosterol, 201 Δ5-avenasterol and 97 Δ7-stigmastenol. Canola lines had significant effects on the contents of oil, brassicasterol and campesterol. Locations had significant effects on the oil, UNSAP, total sterols, brassicasterol, stigmasterol and β-sitosterol. The oil content in canola sprouts was positively correlated with total sterols and Δ5-avenasterol, whereas oil content was negatively correlated with brassicasterol content. In general, the contents of campesterol and β-sitosterol increased with an increase in total sterol content. The concentrations of sterols were in the following decreasing order: β-sitosterol > campesterol > brassicasterol > Δ5-avenasterol > Δ7-stigmastenol > stigmasterol. These results indicate that canola sprouts may have the potential as a natural source of dietary sterols and might be desirable for human nutrition.  相似文献   

2.
Genotype and growing location effects on phytosterols in canola oil   总被引:1,自引:3,他引:1  
There is little information available about phytosterols in canola (Brassica napa L.) oil and the effects of genotype and growing locations from Virginia and the mid-Atlantic region of the United States, a potential area for the establishment of domestic production to provide edible oil. Our objectives were to characterize the phytosterols, phospholipids, unsaponifiable matter, and FA in oil from Virginia-grown canola. Among 11 canola genotypes grown at two locations during 1995–1996 significant variations existed for oil content and FA profiles, but not for contents of phospholipids, unsaponifiable matter, total phytosterols, campesterol, stigmasterol, and β-sitosterol, Total phytosterol content in the oil of Virginia-grown canola varied from 0.7 to 0.9% with a mean of 0.8%. This concentration compared favorably with oil from Canadian canola, which typically contains 0.5 to 1.1% total phytosterols. The mean contents of brassicasterol, campesterol, stigmasterol, β-sitosterol, Δ5-avenasterol, and Δ7-stigmatenol as percentages of total phytosterols in Virginia-grown canola were: 9.7, 32.0, 0.6, 49.3, 4.99, and 3.5%, respectively. Growing location did not affect phytosterols in Virginia-grown canola oil but had significant effects on contents of phospholipids, and saturated (myristic, stearic, and arachidic) and unsaturated (palmitoleic, linoleic, linolenic, eicosenoic, and erucic) FA.  相似文献   

3.
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   

4.
Triterpene alcohols and sterols were separated by thin-layer chromatography and gas-liquid chromatography from the unsaponifiable fractions of the following 18 vegetable oils: linseed, peanut, olive, rice bran, palm kernel, corn, sesame, oiticica, palm, coconut, rapeseed, grape seed, sunflower, poppy seed, castor, tea seed, cocoa butter and soybean. Two triterpene alcohols, cycloartenol and 24-methylene cycloartanol, were found in all of the oils except soybean oil, which contained only cycloartenol. Triterpene alcohols such as α- and β-amyrin, euphorbol, butyrospermol and cyclolaudenol also were encountered occasionally. Three sterols, β-sitosterol, stigmasterol and campesterol were present in all of the oils. In addition a fourth sterol, not yet idenfified, was found in oils of palm, palm kernel and sunflower in varying amounts. This unknown sterol and brassicasterol were found in rapeseed oil in addition to the three sterols that were common to all of the oils studied. Experiment Station for Fats and Oils, National Center for Lipochemistry of National Research Council, Milan, Italy.  相似文献   

5.
4-Demethylsterol and triterpene alcohol compositions of two Vanilla bean species (V. fragrans and V. tahitensis) were investigated. From retention times and gas chromatography-mass spectrometry, nine 4-demethylsterols were identified in V. fragrans and seven in V. tahitensis. The 4-demethylsterol fraction of V. fragrans was characterized by a high content of 24-methylene cholesterol (27–40%) and of β-sitosterol (35–46%). The 4-demethylsterol fraction of V. tahitensis was characterized by a high content of stigmasterol (27%) and of β-sitosterol (57.5%), and a lower amount of 24-methylene cholesterol (5%). Vanilla tahitensis was also characterized by the presence of ergosta-5,25-dien-3β-ol (2%) and the absence of campesterol, stigmasta-5,22,25-trien-3β-ol, and ergosta-7,24(28)-dien-3β-ol. The beans’ age modified the ratio 24-methylene cholesterol/β-sitosterol in V. fragrans. Combining liquid chromatography and gas chromatography allowed the identification of four other demethylsterols in V. fragrans (brassicasterol, 0.02%; stigmasta-5,23-dien-3β-ol, 1.43%; stigmasten-22-ol, 0.1%; and fucosterol, 0.5%) from the 4-demethylsterol fraction. 24-Methylene cholesterol and β-sitosterol were isolated, and their structures were confirmed by 1H and 13C nuclear magnetic resonance. Four triterpene alcohols were identified in V. fragrans, including cycloartenol (0.9–1.6%) from the triterpene alcohol fraction, 24-dihydrotirucallol (17–23%) from the triterpene alcohol fraction, tirucall-7-en-3β-ol (6–7.5%) from the triterpene alcohol fraction, and in a higher content cyclosadol (66–69%) from the triterpene alcohol fraction. The content ranges were studied as a function of the beans’ age. Demethylsterol and triterpene alcohols profile could be used for origin differentiation.  相似文献   

6.
Intravenous lipid constituents have different effects on various biological processes. Some of these effects are protective, while others are potentially adverse. Phytosterols, in particular, seem to be implicated with parenteral nutrition-associated cholestasis. The aim of this study is to determine the amount of plant and animal sterols present in lipid formulations derived from different oil sources. To this end, animal (cholesterol) and plant (β-sitosterol, campesterol, and stigmasterol) sterols in seven different commercially available intravenous lipid emulsions (ILEs) were quantified by capillary gas chromatography after performing a lipid extraction procedure. The two major constituents of the lipid emulsions were cholesterol (range 14–57% of total lipids) and β-sitosterol (range 24–55%), followed by campesterol (range 8–18%) and stigmasterol (range 5–16%). The fish oil-derived formulation was an exception, as it contained only cholesterol. The mean values of the different sterols were statistically different across ILEs (P = 0.0000). A large percentage of pairwise comparisons were also statistically significant (P = 0.000), most notably for cholesterol and stigmasterol (14 out of 21 for both), followed by campesterol (12 out 21) and β-sitosterol (11 out 21). In conclusion, most ILEs combined significant amounts of phytosterols and cholesterol. However, their phytosterols:cholesterol ratios were reversed compared to the normal human diet.  相似文献   

7.
The unsaponifiables separated from 20 vegetable oils were divided into sterol and three other (less polar compound, triterpene alcohol, and 4-methylsterol) fractions by preparative thin layer chromatography. The amounts of the sterol fractions were more than ca. 30% in the unsaponifiables from all of the oils, except tohaku, pumpkin seed, and fagara seed oils. Composition of the sterol fractions were determined by gas liquid chromatography. Individual components of the sterol fractions were identified by gas liquid chromatography and combined gas liquid chromatography-mass spectrometry. β-Sitosterol was found as the most predominant component in the sterol fractions from all oils, except two, i.e. the sterol fraction from pumpkin seed oil contained no detectable amount of β-sitosterol and the sterol fraction from akamegashiwa oil contained Δ5-avenasterol as the most abundant component. Campesterol, stigmasterol, Δ5-avenasterol, Δ7-stigmastenol, and Δ7-avenasterol and also trace amounts (at the very least) of cholesterol and brassicasterol were found in most of the oils analyzed. It may be noted that a large amount (ca. 9%) of cholesterol was detected in the sterol fraction from capsicum seed oil. The presence of 24-methylenecholesterol and Δ5-avenasterol in the sterol fraction of akamegashiwa oil was demonstrated by isolation of these sterols.  相似文献   

8.
Grapefruit seed oil sterols separated from other lipids by Florisil column chromatography were characterized by gas liquid chromatography. The presence of stigmasterol, campesterol and β-sitosterol is indicated. Expressed in terms of peak area, the three sterols are present in proportions of 2.5%, 7.4% and 90.1% of the total, respectively.  相似文献   

9.
The anti-rancidity effect of the unsaponifiable matter fraction of bene kernel (UFB) oil on canola oil (CAO) during frying was compared to that of tert-butyl hydroquinone (TBHQ). The UFB was separated into hydrocarbons (12.9%), carotenes (9.6%), tocopherols and tocotrienols (65.8%, mainly γ-tocopherol), linear and triterpenic alcohols (3.8%), methyl sterols (2.8%), sterols (3.0%, mainly β-sitosterol, stigmasterol, Δ5-avenasterol, and Δ7-avenasterol, respectively), and triterpenic dialcohols (2.2%). The results obtained from the measurements of the total polar compounds, the conjugated diene value, the carbonyl value, and total tocopherols showed that the stability of CAO improves similarly in the presence of UFB or TBHQ, and even more in the presence of UFB in some cases (especially inhibition of oxidized triglyceride monomers and triglyceride dimers). The analysis of polar components showed that the antioxidative additives were more effective to resist the formation of thermo-oxidative than hydrolytic products during the frying of CAO.  相似文献   

10.
Comparative extraction trials were carried out among a classical pressing, a dual-, and a three-phase centrifugation system using olive crops of Koroneiki variety. Two different kneading temperatures, 30 and 45°C, were tested at three stages of ripeness for two consecutive years of harvest, 1995–1996 and 1996–1997. Composition of the sterol fraction was determined in the resulting olive oil samples (n=72). Stigmasterol was found to be affected by the extraction system; it was obtained in the highest amount in the pressing system. The ratio campesterol/stigmasterol was significantly higher in oils extracted by dual- and three-phase centrifugation. Sterols were significantly affected by the ripening stage of the fruit. During December, the ratio campesterol/stigmasterol reached the maximal and β-sitosterol the minimal values; this appears to be the optimal period for harvesting the olives. Comparison of the different kneading temperatures showed that at 30°C, Δ5-avenasterol and campesterol/stigmasterol ratio reached higher values than at 45°C.  相似文献   

11.
The unsaponifiables from threeTheaceae (Camellia japonica L.,Camellia Sasanqua Thunb., andThea sinensis L.) oils and alfalfa, garden balsam, and spinach seed oils and shea fat were separated into four fractions: sterols, 4-methylsterols, triterpene alcohols, and less polar compounds by thin layer chromatography. While the sterol fraction was the major one for the unsaponifiables from alfalfa and spinach seed oils, the triterpene alcohol fraction was predominant for the unsaponifiables from all other oils. The sterol, 4-methylsterol, and triterpene alcohol fractions were analyzed by gas chromatography. All the sterol fractions were alike in their compositions, consisting exclusively of Δ7-sterols, such as α-spinasterol and Δ7-stigmastenol as predominant components together with Δ7-avenasterol and 24-methylcholest-7-enol. Obtusifoliol, gramisterol (occasionally accompanied with cycloeucalenol), and citrostadienol, together with several other unidentified components, were found in the 4-methylsterol fractions from all of the oils except shea fat. The 4-methylsterol fraction from shea fat showed a characteristic composition containing a large proportion of unidentified components which had relative retention time greater than that of citrostadienol, while no citrostadienol was detected. β-Amyrin, lupeol, and butyospermol were major components of the triterpene alcohol fractions from most of the oils, but the fraction from spinach seed oil contained cycloartenol and 24-methylene-cycloartanol as predominant components. There is a close similarity in the compositions of unsaponifiables (sterols, 4-methylsterols, and triterpene alcohols) of the threeTheaceae oils. Two sterols, α-spinasterol and Δ7-stigmastenol, and five triterpene alcohols were isolated from tea seed oil. Moreover, five unidentified components beside parkeol, butyrospermol, α-amyrin, and lupeol were isolated from the triterpene alcohol fraction of shea fat.  相似文献   

12.
The content and composition of fatty acids, sterols, tocopherols, and γ-oryzanol in wild rice (Zizania palustris) grown in North America were compared with those in regular brown rice (Oryza sativa L.). The lipid content of wild rice ranged from 0.7 to 1.1%, compared with 2.7% in regular brown rice. The lipids of wild rice comprised mainly linoleic (35–37%) and linolenic (20–31%) acids. Other fatty acids included palmitic (14.1–18.4%), stearic (1.1–1.3%), and oleic (12.8–16.2%). Wild rice lipids contained very large amounts of sterols, ranging from 70 g/kg for a Saskatchewan sample to 145 g/kg for Minnesota Naturally Grown Lake and River Rice. The main sterols found in an unsaponified fraction were: campesterol (14–52%), β-sitosterol (19–33%), Δ5-avenasterol (5–12%), and cycloartenol (5–12%). Some of sterols, γ-oryzanols, were present as the phenolic acid esters; the amount ranged from 459 to 730 mg/kg in wild rice lipids. The largest amounts of tocopherols and tocotrienols, 3682 and 9378 mg/kg, were observed in North Western Ontario wild rice samples, whereas the lowest were 251 mg/kg in an Athabasca Alberta sample and 224 mg/kg in regular long-grain brown rice. The α isomer was the most abundant among tocopherols and tocotrienols. The results of this study showed that wild rice lipids contain large amounts of nutraceuticals with proven positive health effects.  相似文献   

13.
The sterols and fatty acids ofPsilotum nudum were investigated. The 4,4-dimethyl- and 4α-methylsterol fractions contained 24β-methyl-Δ25-unsaturated sterols,viz., cyclolaudenol and 24β-methyl-25-dehydrolophenol, respectively, as dominant sterols among the other components common in vascular plants. 24-Methylcholesterol (mixture of C-24 epimers) and sitosterol constituted the dominant sterols in the 4-demethylsterol fraction. This is the first identification of 24-methylene-5α-lanost-8-en-3β-ol, 24β-methyl-25-dehydrolophenol, codisterol, isofucosterol, 24-methylene-25-methylcholesterol and avenasterol in a fern. The major fatty acids were 16:0, 18:1, 18:2, 18:3 and 20:3. In addition, several C20 fatty acids with various unsaturation were found to be present in low concentrations.  相似文献   

14.
To assess the potential of traditional selection breeding to develop varieties with increased phytosterol content, we determined concentrations of those sterols in canola, sunflower, and soybean seed oils produced from breeding lines of diverse genetic backgrounds. Seed oils were extracted and saponified, and the nonsaponifiable fractions were subjected to silylation. The major phytosterols brassicasterol, campesterol, stigmasterol and β-sitosterol, were quantified by capillary gas chromatography with flame-ionization detection. Canola contained approximately twice the amount of total phytosterols (4590–8070 μg g−1) as sunflower (2100–4540 μg g−1) or soybean (2340–4660 μg g−1) oils. Phytosterol composition varied among crops as expected, as well as within a crop. Both genetic background and planting location significantly affected total phytosterol concentrations. Soybean plants were maintained from flower initiation to seed maturity under three temperature regimes in growth chambers to determine the effect of temperature during this period on seed oil phytosterol levels. A 2.5-fold variability in total phytosterol content was measured in these oils (3210–7920 μg g−1). Total phytosterol levels increased with higher temperatures. Composition also changed, with greater percent campesterol and lower percent stigmasterol and β-sitosterol at higher temperatures. In these soybean oils, total phytosterol accumulation was correlated inversely with total tocopherol levels. Owing to the relatively limited variability in phytosterol levels in seed oils produced under field conditions, it is unlikely that a traditional breeding approach would lead to a dramatic increase in phytosterol content or modified phytosterol composition.  相似文献   

15.
Plant sterols and triterpenes exhibit a wide range of pharmacological activities. As part of our ongoing studies of the medicinal aspects of Maritime flora, particularly the herbal remedies of the Micmac and Malecite Indians, we determined the nature of the sterols and triterpenes ofTanacetum vulgare L. (Compositae)—a widely used herbal remedy usually referred to as tansy. By using thin layer and gas chromatographics, nuclear magnetic resonance (NMR) spectroscopy and combined gas chromatography-mass spectrometry, we were able to identify β-sitosterol as the major sterol and α-amyrin as the major triterpene of tansy. We also identified the sterols stigmasterol, campesterol and cholesterol, and the triterpenes β-amyrin and taraxasterol. A fourth triterpene was tentatively identified as pseudo-taraxasterol. The successful therapeutic application of this herb may be due partly to the presence of one or more of these compounds. The sterols and triterpenes of tansy have not been previously reported; neither, to our knowledge, have the NMR spectra of the amyrins and the NMR and mass spectra of taraxasterol.  相似文献   

16.
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   

17.
Camelina oil and its unusual cholesterol content   总被引:1,自引:1,他引:1  
The oil in Camelina sativa L. Crantz has a combined linolenic and linoleic acid content that is greater than 50% and a relatively low saturated FA content (∼10%). Although the FA composition has been reported, no information is available on the sterol composition of camelina oil. The derivatized plant sterols were separated and quantified with capillary GC and their identity confirmed with GC-MS. The refined camelina oil sample contained approximately 0.54 wt% unsaponifiables, and over 80% of the unsaponifiables were desmethylsterols. Perhaps the most unusual characteristic of camelina oil is its relatively high content of cholesterol, particularly for a vegetable oil, since it contains several times the cholesterol found in other “high-cholesterol” vegetable oils. Camelina oil also contains relatively large amounts of another unusual sterol, brassicasterol. The major sterols identified in the camelina oil included cholesterol (188 ppm), brassicasterol (133 ppm), campesterol (893 ppm), stigmasterol (103 ppm), sitosterol (1,884 ppm), and Δ5-avenasterol (393 ppm).  相似文献   

18.
Recovered fiber from pressed palm fruits, which is normally burned as fuel to provide energy for the palm oil mills, has now been found to be a rich source of carotenoids, vitamin E (tocopherol and tocotrienols), and sterols. Residual oil (5–6% on dry basis) extracted from palm press fibers contains a significant quantity of carotenoids (4000–6000 ppm), vitamin E (2400–3500 ppm), and sterols (4500–8500 ppm). The major identified carotenoids are α-carotene (19.5%), β-carotene (31.0%), lycopene (14.1%), and phytoene (11.9%). In terms of vitamin E, α-tocopherol constitutes about 61% of the total vitamin E present, the rest being tocotrienols (α-, γ-, and δ-). The major sterols present are β-sitosterol (47%), campesterol (24%), and stigmasterol (15%). The oil extracted from palm-pressed fiber is contaminated with about 30% of palm kernel oil. The quality of this fiber oil is slightly lower than that of crude palm oil in terms of the content of free fatty acids, peroxide value, and anisidine value.  相似文献   

19.
A comprehensive lipid profiling of the oil from the edible mophane caterpillar, Imbrasia belina, has been carried out as part of the study of the nutritional value of the caterpillar. GC-MS analysis revealed the composition of the major FA classes as 18:3 (29.98%), 16:0 (25.64%), 18:1 (17.97%), 18:0 (12.49%) and 18:2 (11.81%), which was in agreement with reported GC-FID analysis of the phane oil. ESI-FTICR mass spectrometric analysis showed phane oil to contain 20 TAG classes, with C54:4 (14.59%), C52:3 (14.71%) and C52:2 (10.49%) being the dominant classes, whilst 13C-NMR studies of the TAGs regiochemistry showed that occupancy of the sn-2 position was dominated by linolenyl and linoleoyl groups whereas the sn-1/3 positions were dominated by saturated groups. Normal-phase HPLC analysis of the unsaponifiable matter showed the presence of α-tocopherol (71.39 μg/g) and γ-tocopherol (1.66 μg/g) as the only tocol content in phane oil. GC-MS analysis of the total acetylated unsaponifiable matter gave the relative composition of the major sterols as cholesterol (53.77%), β-sitosterol (24.16%), 22-dehydrocholesterol (14.58%) and campesterol (6.26%), whilst GC-MS analysis of an SPE pre-fractionated unsaponifiable matter gave the absolute 4-desmethylsterol content (μg/g) as cholesterol (4482.44), β-sitosterol (1861.95), 22-dehydrocholesterol (1274.53), campesterol (503.83) and stigmasterol (21.78). Perhaps the adverse effect of such high dietary cholesterol content on humans could be mitigated by the presence of the substantial amounts of β-sitosterol and campesterol which are known to be blood plasma cholesterol lowering phytosterols.  相似文献   

20.
Two samples of virgin olive oil and one sample of hexane-extracted husk oil coming from Iran were examined. The analyses included physical and chemical characteristics, the composition of total fatty acids and fatty acids at the glyceride 2-position by gas liquid chromatography (GLC) of methyl esters, the triglycerides composition calculation according to Vander Wal theory, the separation of the alcoholic fractions (sterols, 4-methylsterols, triterpene alcohols, triterpene dialcohols and aliphatic alcohols) of the unsaponifiable matter by thin layer chromatography (TLC), the quantitation and the composition of these fractions by GLC of TMS derivatives. The results were in line with data from literature for olive oils of different origin, with the exception of: a high content of unsaponifiable matter (1.75 and 1.95% for virgin oils, 5.33% for husk oil); a high amount of sterols for husk oil (562 mg/100 g oil); a low content of SE 30 apparent β-sitosterol for husk oil (91.1%); a low amount of triterpene dialcohols (1 mg/100 g oil) and triterpene alcohols (78 and 91 mg/100 g oil) for virgin oils; a content of cycloartenol (60.2–66.9%) higher than the 24-methylenecycloartanol one (22.8–26.6%; a content of C24 linear saturated alcohol (33.9–38.0%) slightly higher than the C26 alcohol one (29.3–32.8%).  相似文献   

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