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1.
The lipids extracted from various fungi belonging to the generaAspergillus, Fusarium andPenicillium cultivated on Davis medium were studied. The fatty acids from fungal lipids were fractionated by gas liquid chromatography (GLC) and the main fatty acids were palmitoleic, oleic, stearic, linoleic and arachidic. The results demonstrated that the fatty acid composition of various fungi could be used as criteria for fungal taxonomy. The unsaponifiable matter of the fungi could be divided into two fractions, i.e., hydrocarbons and sterols. The hydrocarbon fraction constitutes an important part because its amount ranged from 30.14 to 80.97% according to the fungal species. The sterol fraction of the unsaponifiable part of fungal lipids was much simpler in composition. Analysis by GLC indicated that sterol composition could be used to differentiate among fungi belonging to different genera as well as among species belonging to one genus.  相似文献   

2.
Pumpkin seed oils from naked and husk pumpkin seeds, produced by an industrial process and by laboratory extraction, were evaluated for fatty acid composition, tocopherol, sterol and squalene content. The major fatty acids in the oils from both varieties were oleic, linoleic and palmitic acid, followed by stearic acid. The ratios of monounsaturated to polyunsaturated fatty acids for husk and naked seed oils were about 0.60 and 0.75, respectively. Analysis of tocopherols in industrially pressed and laboratory‐extracted oils showed that husk seed oils had higher amounts of total tocopherols than naked seed oils. Oils extracted in the laboratory had higher amounts of tocopherols than industrial oils. Pumpkin seed oil, in general, had a high level of squalene, which was higher in husk seed oils than in naked seed oils and in extracted than in pressed oils. The total amount of sterols was higher in husk than in naked seed oils and in extracted oil samples. The main sterols were Δ7‐sterols and their content was similar in all samples, but the content of Δ5‐sterols was higher in oil samples of husk pumpkin seed and in extracted than in pressed oils.  相似文献   

3.
Oxidative stabilities of crude soybean oils obtained by different extraction solvents such as hexane, water and Folch's solvent (mixture of two volumes of chloroform and one volume of methanol) were determined by gas chromatographic analyses of headspace and peroxide value of oil samples. For the determination of oxidative stability of oil samples, total volatile compounds formation, molecular oxygen disappearance in the headspace and peroxide value of oil samples were measured. Iodine value (133–136), saponification value (195–198), unsaponifiable matters (0.3–0.4%), iron (0.6 ppm), sterols content (2,400–2,590 ppm), tocopherols content (1,250–1,520 ppm) and fatty acid composition of crude oils obtained by different solvent extraction were not significantly different. Acid value of Folch-extracted oil was the highest as 1.3, whereas those of hexane-and aqueous-extracted oils were 0.5 and 0.4, respectively. Crude soybean oil extracted by Folch's method was found to contain the most phosphorus, while hexane- and aqueous-extracted oils contained similar amounts of phosphorous. Crude soybean oil obtained by Folch extraction was most stable in oil oxidation, and oxidative stabilities of oils obtained by hexane and aqueous extraction, which were significantly much less stable than Folch-extracted oil, were not significantly different during ten weeks storage.  相似文献   

4.
This work focused on physicochemical property assaying, fatty acid composition, triacylglycerol (TAG) profiles, and unsaponifiable matter composition of the Chinese Moringa oleifera seed oil. The results indicated that there was no significant difference in approximate nutritional components between M. oleifera seeds from China and India, while variations in the mineral element contents are significant. Both the Soxhlet extraction method and the aqueous enzymatic extraction method were adopted to extract oil from Chinese M. oleifera seeds. Oil yield obtained using the Soxhlet extraction method was higher than that obtained using the aqueous enzymatic extraction method. While both the iodine value and unsaponifiable matter content of the aqueous enzymatic extracted oil were a little higher than that of the Soxhlet extracted oil. Both oils possess a very low acid value and peroxide value, suggesting their good quality as edible oil. Fatty acid composition results indicated that this oil was especially high in oleic acid. Characterization of the TAG composition was achieved by a two-dimensional high-performance liquid chromatography (HPLC) coupling of nonaqueous reverse-phase and silver ion HPLC with the atmospheric pressure chemical ionization mass spectrometry method. A total of 22 TAG including 16 regioisomers were determined. Composition results of unsaponifiable matters revealed that this oil possesses a number of phytosterols, in which β-sitosterol and stigmasterol are most predominant.  相似文献   

5.
Oil extracted from condensed corn distillers solubles (CCDS) can form a semi-solid and waxy precipitate at the bottom of containers during storage. CCDS is a good source to recover oil, and such oil can be converted to biodiesel. Precipitate formation in the extracted oil is mainly a physical stability problem, but it may become a performance problem for biodiesel. The objective of the present work was to determine the composition of the CCDS oil precipitate and also determine if valuable phytosterols were present in high concentration. The free fatty acid (FFA) content was very high, 35.7%, and fatty acid composition of the FFA fraction was predominantly palmitic acid, 70.3%. The solid appearance was mainly due to a high percentage of high-melting point free saturated fatty acid. The total unsaponifiable matter was 2.0%, and total phytosterol content was 8.6 mg/g of CCDS oil precipitate. Therefore, CCDS oil precipitate is a not an enriched source of phytosterols compared to total sterols present in crude corn oil (15.6 mg/g oil). The wax content was high, 2.5 mg/g of CCDS oil precipitate compared to 0.5 mg/g of crude corn oil. CCDS oil that is uncentrifugable but polar solvent extractable (trapped oil fraction) was also characterized and found to contain more polar lipids than those in the free oil fraction (centrifugable oil).  相似文献   

6.
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   

7.
The fatty acid (FA) composition of Oenocarpus bataua oil from 38 samples collected over a large geographical range (i.e. French Guiana and Peru) was analyzed. Fifteen fatty acids were obtained from the mesocarp of this palm species. Oleic (72.7%) and palmitic (18.1%) acids were the predominant FAs. Minor FAs were cis-vaccenic acid (2.3%), linoleic acid (1.9%), stearic acid (1.7%), palmitoleic (0.9%) and alpha-linolenic acid (0.8%). The mean lipid content of the dry mesocarp was 51.6%. The O. bataua oil samples analyzed were remarkably rich in α-tocopherol. By contrast, the other fractions of the unsaponifiable matter (sterols, carotenoids) did not show any noteworthy specificity in comparison with common vegetable oils. However, the particularly high percentage in Δ5-avenasterol of O. bataua oil could serve as a marker for its authentication. Results are discussed in terms of the potential nutritional value of O. bataua oil.  相似文献   

8.
Seeds of the citrus fruits orange, mandarin, lime and grapefruit were analyzed. Petroleum ether-extracted oils of such seeds amounted to more than 40% of each. Physical and chemical properties of the extracted oils are presented. Samples of the extracted oils were saponified and the unsaponifiables and fatty acid fractions isolated. The isolated unsaponifiables and fatty acids were analyzed by GLC. GLC analysis of the unsaponifiables revealed compositional patterns differ-ent in number, type and relative concentration of fractions according to type of citrus seed oil, depending on the solvent system used for oil extraction and unsaponifiable matter isolation. The compositional patterns of the unsaponifiables were similar to that of cottonseed oil. Mandarin and grapefruit oils are free of cholesterol. The data demonstrate that the fatty acid compositional patterns of the oils differ; Mandarin seed oil contains the largest number of fatty acids, and grapefruit seed oil contains the lowest. The total amounts of volatile fatty acids in these oils are generally higher than those of other edible oils. Lime seed oil is similar, in the degree of unsaturation, to soybean oil. The orange oil pattern is similar to cottonseed oil. The amount of total essential fatty acids in lime seed oil is the highest of the oils studied.  相似文献   

9.
This study compared the profiles of fatty acids, phytosterols, and polyamine conjugates in conventional commercial corn oil extracted from corn germ and in two “new-generation” corn oils: hexane-extracted corn fiber oil and ethanol-extracted corn kernel oil. The fatty acid compositions of all three corn oils were very similar and were unaffected by degumming, refining, bleaching, and deodorization. The levels of total phytosterols in crude corn fiber oil were about tenfold higher than those in commercial corn oil, and their levels in crude corn kernel oil were more than twofold higher than in conventional corn oil. When corn kernel oil was subjected to conventional degumming, refining, bleaching, and deodorization, about half of the phytosterols was removed, whereas when corn fiber oil was subjected to a gentle form of degumming, refining, bleaching, and deodorization, only about 10% of the phytosterols was removed. Finally, when the levels of polyamine conjugates (diferuloylputrescine and p-coumaroyl feruloylputrescine) were examined in these corn oils, they were only detected in the ethanol-extracted crude corn kernel oil, confirming earlier reports that they were not extracted by hexane, and providing new information that they could be removed from ethanol-extracted corn kernel oil by conventional degumming, refining, bleaching, and deodorizing.  相似文献   

10.
The objective of this study was to investigate and compare fatty acids, tocopherols and sterols of kenaf seed oil extracted by supercritical carbon dioxide and traditional solvent methods. Fatty acids, tocopherols and sterols were determined in the extracted oils as functions of the pressure (400 bar, 600 bar), temperature (40 °C, 80 °C) and CO2 flow rate (25 g/min) using a 1-L extraction vessel. Gas chromatography was used to characterize fatty acids and sterols of the obtained oils while tocopherols were quantified by HPLC. No differences were found in the fatty acid compositions of the various oil extracts and the main components were found to be linoleic (38%), oleic (35%), palmitic (20%) and stearic acid (3%). Extraction of tocopherols using high pressure (600 bar/40 °C, 600 bar/80 °C) gave higher total tocopherols (88.20 and 85.57 mg/100 g oil, respectively) when compared with hexane extraction which gave yield of 62.38 mg/100 g oil. Extraction of kenaf seed oil using supercritical fluid extraction at high temperature (80 °C) gave higher amounts of sterols when compared with hexane extraction.  相似文献   

11.
The crude oil extracted from soy flakes with supercritical carbon dioxide (SCCO2) was characterized for color, free fatty acid, phosphorus, neutral oil loss, unsaponifiable matter, tocopherol and iron content and compared to a commercial hexane-extracted sample of crude degummed oil. Characterization and processing studies indicate that SCCO2 extraction yields a product comparable to a hexane-extracted degummed oil. However, hexane-extracted degummed soybean oils exhibit better oxidative stability because phosphatides, which are natural antioxidants, are essentially absent in SCCO2-extracted oils. Presented at AOCS Meeting, Toronto, May, 1982.  相似文献   

12.
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   

13.
In this study in order to introduce a new vegetable oil, oxidative stability and chemical characteristics of Pistacia khinjuk kernel oil (PKKO) as compared with P. atlantica kernel oil (PAKO) and extra virgin olive oil (EVOO) were investigated. Oxidative stability of studied oils was considered based on the conjugated diene value (CDV), carbonyl value (CV) and oil/oxidative stability index (OSI) through an 8‐h thermal process at 170 °C. Also, chemical characteristics [fatty acid composition, unsaponifiable matter (USM), total tocopherols (TT), total phenolics (TP) and total sterols (TS), iodine value, saponification number and waxes] of these oils were analyzed. The ratio of polyunsaturated fatty acids to saturated fatty acids and the oxidizability (Cox) value of PKKO (1.14 and 2.78; respectively) were between those of PAKO (2.37 and 4.23; respectively) and EVOO (1.14 and 2.78; respectively). USM content of the three studied oils was between 1.1 and 1.51 %. TT and TP contents of PKKO (619.4 and 26.6 ppm) were lower than those of PAKO (845.33 and 75.22 ppm) and higher than those of EVOO (365.23 and 19.78 ppm). TS contents of PKKO, PAKO and EVOO were 2,500, 2,150 and 3,800 ppm, respectively. Oxidative stability data indicated that PKKO is the most resilient oil against lipid oxidation, followed by PAKO and EVOO. CDV significantly increased by the lowest speed for PKKO, followed by PAKO and EVOO. Increase of CV and reduction of OSI for PKKO, PAKO and EVOO were 29.2, 128 and 338.7 and 32.8, 67.9 and 79.3 %; respectively.  相似文献   

14.
Samples of crushed and cooked canola seeds (Okapy Double Zero) were extracted using supercritical carbon dioxide (SCCO2) (34.0 MPa and 40.0 °C) and a commercial organic solvent (AW406). Oil solubility was obtained through several stepwise extractions under the conditions of this study, and then three additional extractions were performed to measure fatty acid compositions, iodine values, chlorophyll concentrations and unsaponifiable matter. The yield of SCCO2 extraction was lower than that after extraction with AW406 solvent, due to the incomplete SCCO2 extraction process. Fatty acid composition analysis showed that the SCCO2‐extracted oil was slightly higher in polyunsaturated fatty acids and lower in erucic and behenic acids. However, iodine values and unsaponifiable matter did not indicate significant differences (p >0.05) in the two extracted oils. The chlorophyll concentration of SCCO2‐extracted oil was lower than that in the AW406 solvent, and as a result, the color of SCCO2‐extracted oil was lighter.  相似文献   

15.
The effects of enzyme‐assisted cold‐pressing (EACP) on the physicochemical attributes of Cannabis sativa (hemp) seed oil were investigated using five enzyme preparations: Protex 7L, Viscozyme L, Kemzyme, Feedzyme, and Natuzyme. The oil contents (28.4–32.8%) offered by the enzyme‐treated hempseeds were found to be significantly (p <0.05) higher than that determined for the control (26.7%). The protein, fiber, and ash contents of the seeds were unaffected by the enzyme treatment. There were no significant (p >0.05) variations observed for the values of iodine number, refractive index, density, unsaponifiable matter and fatty acid composition between the enzyme‐extracted and control hempseed oils. The levels of saponification value, free fatty acids, iodine value and peroxide value were slightly varied between the oils tested. The color intensity of the enzyme‐extracted oils was also higher than that of the control oil. A relatively higher level of tocopherols (724.4–788.8 mg/kg) was observed in the enzyme‐extracted oils compared to the control (691.2 mg/kg), showing an enhancement of ca. 4.8–14.1% in the total tocopherols. The Rancimat profiles and sensory scores of the enzyme‐extracted oils were noted to be improved compared to the control. The results of the present analysis (with respect to the control) showed that the enzyme added during the hempseed cold‐pressing resulted in considerably higher oil yields, without adversely affecting the quality of the oil.  相似文献   

16.
Acorn fruit oils from two species of oak, Quercus rotundifolia L. (holm‐oak) and Quercus suber L. (cork‐oak), were extracted by n‐hexane. The acorn fruit of Quercus rotundifolia L. was also extracted by supercritical CO2 at 18 MPa and 313 K, a superficial velocity of 2.5 × 10?4 ms?1, and a particle size diameter of 2.7 × 10?4 m. The oils were characterised in terms of fatty acids, triglycerides, sterols, tocopherols, and phospholipids. The main fatty acid in both fruit species was oleic acid (about 65%), followed by linoleic acid (about 16.5–17%) and palmitic acid (about 12.1–13.4%). The main triglyceride found in acorn oils was the OOO (oleic, oleic, oleic) triglyceride (33–38%), followed by the POO (palmitic, oleic, oleic) triglyceride (12.6–18.2%). In terms of sterols, the main component in acorn oils of both species was β‐sitosterol (83.5–89%), followed by stigmasterol (about 3%). However, in Quercus suber L., acorn oil was found to consist to 10.2% of campesterol. The amount of cholesterol was low (0.27% for the Quercus rotundifolia L. oil extracted by supercritical fluid extraction, and 0.18% for the oil extracted by n‐hexane). The Quercus suber L. acorn oil presented 0.1% of cholesterol. The total amount of tocopherols in Quercus rotundifolia L. acorn oils was almost the same when the oil was extracted by n‐hexane (973 mg/kg oil) or by supercritical CO2 (1006 mg/kg oil). The Quercus suber L. acorn oil presented a high value of total tocopherols (1486 mg/kg oil). The supercritical CO2 did not extract the phospholipids. The amount of phospholipids was very similar for both species of oak acorn oils extracted by n‐hexane. Oxidative stability was also studied, by using the peroxide value and the Rancimat method, revealing that all the oils were significantly protected against oxidation. The influence of storage, under several conditions, on the oxidative stability was also studied. The Quercus rotundifolia L. oil extracted by n‐hexane was better protected against oxidation after a few days of storage at 60 °C.  相似文献   

17.
A home-built version of the automated AOM test was used with Canola, corn, sunflower, olive and Crisco? oils, shortening and lard. The endpoint was found by measuring the conductivity of a solution of the exit gas from the reaction tube. Coefficients of variability of the samples ranged from 1.1% to 8.3%. The endpoint of the test was ca. 100 PV for Canola oil, ca. 200 PV for corn oil and 35 PV for lard. The aqueous solutions of the volatiles of three oils were used to determine the TBA value. Canola, sunflower and olive oil had TBA values ranging from 6–60 μg malonaldehyde/g at the end point. No apparent relationship was found between the TBA values of the volatiles’ solutions and the PV’s of the oils. Presented at the 73rd AOCS Annual Meeting, Toronto, 1982.  相似文献   

18.
Edible refined, bleached and deodorized (RBD) soybean oil was fractionated by silicic acid column chromatography to identify minor components responsible for flavor reversion. Minor components from oil eluted with diethyl ether/n-hexane (1:1) were compared with those from corn and canola oils. All vegetable oils contain free fatty acids, diglycerides and sterols as major ingredients in this fraction. However, unusual triglycerides consisting of 10-oxo-8-octadecenoic acid and 10-and 9-hydroxy octadecanoic acids were detected in RBD and crude soybean oils.  相似文献   

19.
Fractionation of sterols from plant lipid mixtures was accomplished using a multistep supercritical fluid extraction (SFE) procedure. Samples of seed oils, margarine, corn germ oil, and corn fiber oil were extracted to yield enriched phytosterol fractions. Supercritical fluid chromatography (SFC) was utilized to separate and determine the concentration of the plant sterols in the extracts from the various samples. The sterol concentration in the original samples varied from 2.2 mg/g in soybean oil to 13.2 mg/g in oil extracted from corn fiber. After the SFE-based fractionation of the samples, the sterol concentration was increased to 64.4 mg/g in the extract from soybean oil and 166.2 mg/g in the extract from corn fiber oil. Oil extracted from corn bran, which measured 8.6 mg/g in the original oil, increased to 322.2 mg/g using the fractionation process. The benign conditions utilized by SFE and SFC proved to be effective for the analyses of these compounds without inducing degradation of the analytes.  相似文献   

20.
This study investigated the content and composition of total, free, and esterified sterols of three varieties of lotus plumule oil (Hunan lotus, Jiangxi lotus, and Fujian lotus) using GC–MS/FID. The fatty acid composition of sterol fatty acid esters (SFAE) was also analyzed and compared with that of triglycerides. Results showed that total sterol of lotus plumule oil (12.10–14.21 g/100 g) was higher than that of other plant oils (corn germ oil, 1.11 g/100 g; rapeseed oil, 0.78 g/100 g). No significant difference was found among the total sterol contents of the three types of lotus plumule oils (p > 0.05). Most sterol existed in ester forms (81.8–89.1%) rather than in free forms (8.4–10.1%). β‐Sitosterol (71.4–73.4%), and campesterol (6.2–7.5%) were the predominant fractions of free sterols. β‐Sitosterol (41.3–53.7%) and ?5‐avenasterol (27.1–31.1%) were the predominant fractions of esterified sterols, followed by campesterol (12.1–13.0%) and ?7‐avenasterol (3.4–3.7%). Linoleic acid (63.6–65.8%), oleic acid (8.3–10.4%), and behenic acid (9.0–9.9%) were the main fatty acids of SFAE, which were different from those of triglycerides. The results from this study suggest that lotus plumule oil may be a good resource of SFAE and can be used as a supplemental ingredient in functional foods.  相似文献   

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