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1.
It was shown that two bicyclic fatty acids present in Finnish tall oil were formed from (5Z, 9Z, 12Z)-5, 9, 12-octadecatrienoic acid, pinolenic acid (I). Under the alkaline conditions of sulfate pulping, pinolenic acid forms conjugated isomers which undergo Diels-Alder cyclization during the heating in the tall oil distillation. The cyclization products, here called cyclopinolenic acids, are bicyclic fatty acids and stereoisomers of 4-(5-pentyl-3a, 4,5,7a-tetrahydro-4-indanyl) butanoic acid (IV and V).  相似文献   

2.
Detection and Determination of Cyclic C18-Fatty Acids in Isomerised Linseed Oil When linseed oil is isomerised with ethylene glycol and KOH under conditions which are employed for the UV-spectrophotometric determination of linoleic and linolenic acids, isomeric C18-cyclic fatty acids to an extent of 10% of the linseed oil (20% of linolenic acid) are formed besides straight chain conjugated fatty acids. Lesser amount of cyclic acids are formed if the isomerisation is carried out with NaOH-ethylene glycol or K-tert-butylate. Ilinol, a linseed oil obtained by catalytic isomerisation with Ni/S, was found to contain ca. 5% cyclic C18 fatty acids. The cyclic fatty acids are mixtures of many isomers, their composition being dependent on the conditions employed for isomerisation.  相似文献   

3.
The fatty acid profile of kenaf (Hibiscus cannabinus L.) seed oil has been the subject of several previous reports in the literature. These reports vary considerably regarding the presence and amounts of specific fatty acids, notably (12,13-epoxy-9(Z)-octadecenoic (epoxyoleic) acid, but also cyclic (cyclopropene and cyclopropane) fatty acids. To clarify this matter, two kenaf seed oils (from the Cubano and Dowling varieties of kenaf) were investigated regarding their fatty acid profiles. Both contain epoxyoleic acid, the Cubano sample around 2 % and the Dowling sample 5-6 % depending on processing. The cyclic fatty acids malvalic and dihydrosterculic were identified in amounts around 1 %. Trace amounts of sterculic acid were observed as were minor amounts of C17:1 fatty acids. The results are discussed in the context of the fatty acid profiles of other hibiscus seed oils.  相似文献   

4.
Research on peanut (Arachis hypogeae L.) genotypes has shown a high degree of genetic variability in fatty acid composition. The two major oil fatty acids, oleic and linoleic, range between 36–69% and 14–40%, respectively, and together make up 75–85% of total fatty acids. The very long chain (C20–C24) fatty acids make up 4–9%, palmitic acid 7–13%, and stearic acid 2–5% of total fatty acids. Stability of oil samples as measured by length of autoxidation induction period at 60 C shows variable but statistically significant (P<0.01) correlations with levels of linoleic acid; peanut butter samples show similar patterns of stability. Selection for lower levels of linoleic acid in the development of new varieties of peanuts should results in products with significantly improved shelf life. Some genotypes show consistent differences in oil stability patterns that are not related to oil linoleic acid content. Analysis of entries from 16 wildArachis species collections revealed levels of oil linoleic acid higher than those found inA. hypogaea. One species,A. villosulicarpa, contained 49% linoleic acid and 21% very long chain acids. The range in linoleic acid withinA. hypogaea and availability of suitable techniques for measuring selection progress give scope for product improvement through breeding.  相似文献   

5.
The volatile free fatty acids were analyzed in commercial french- fried potatoes that had been deep- fried in beef tallow- hydrogenated vegetable oil shortening. The results showed that many of the volatile fatty acids present in beef tallow were transferred to the potatoes. Of the fatty acids derived from beef tallow, butanoic, 2-methylbutanoic, 3- methylbutanoic, heptanoic, 4-methyltanoic, and nonanoic acids were present in concentrations above their respective thresholds, and should contribute to tallow- like flavors. Several unsaturated volatile fatty acids also were identified, and they should contribute to the general deep- fried potato flavor.  相似文献   

6.
trans-3,5-Dimethoxystilbene has been isolated from high quality tall oil fatty acids (unsaponifiables 1.5% maximum, rosin acids 1.5% maximum), using liquid column chromatography and low temperature solvent fractional crystallization. The structure of this compound was determined with the aid of IR, mass and NMR spectrometry. Thetrans-3,5-dimethyoxystilbene was found to be responsible for the development of a red color during the epoxidation of the tall oil fatty acids.  相似文献   

7.
Expeller pressed crudeHibiscus sabdariffa seed oil (mesta oil) is dark and most unappealing. On refining, the appearance of the oil is improved. The unusual fatty acids present in theH. sabdariffa seed oil, cyclopropene acids (malvalic C18H32O2 and sterculic C19H34O2) and epoxy oleic acid (C18H32O3), are not reduced by refining. Partial hydrogenation did not reduce the epoxy oleic acid, but it eliminated the cyclopropene acids. Heating for 10 min was sufficient for complete elimination of cyclopropene acids, but heating up to 60 min did not affect the epoxy acid.  相似文献   

8.
The importance of the fatty acid industry today is reflected by the estimated 1978 production in the U.S. of 956 M lbs., exclusive of tall oil fatty acids. The 1978 U.S. production of various fatty acids as reported monthly and annually by the FAPC of SDA, is broken down into 9 saturated categories, and 5 unsaturated categories, as follows: (1) stearic and 127.2 M lbs. (13.3%); (2) hydrogenated animal and vegetable acids (2a) 97.3 M lbs. (10.2%), (2b) 158 M lbs. (16.5%), (2c) 32 M lbs. (3.4%); (3) high palmitic, 14.6 M lbs. (1.5%); (4) hydrogenated fish, 6.5 M lbs. (0.7%); (5) lauric acid types, 88.8 M lbs. (9.3%); (6) fractionated fatty acids, (6a) C10 or lower, 18.5 M lbs. (1.9%), (6b) C12 and C14 55% 17 M lbs. (1.9%); (7) oleic acid, 158.3 M lbs. (16.6%); (8) animal fatty acids other than oleic, 156.3 M lbs. (16.3%); (9) vegetable or marine fatty acids, 0.1 M lbs. (less than 1%); (10) unsaturated fatty acids, 57 M lbs. (6.0%); (11) unsaturated fatty acids I.V. over 130, 24.2 M lbs (2.5%). Reported 1977 fatty acid derivative production from fatty acids (not fats and oils) is 1,980 M lbs. The average price of fatty acids has increased from 23¢/lb.. to 60¢/lb. within the last 5 years.  相似文献   

9.
A novel route for the synthesis of naturally occurring furan fatty acids with particular emphasis on labeling with14C is described. Methyl [2-14C] 9-(5-pentyl-3,4-dimethyl-2-furyl)nonanoate was synthesized from 3,4-dimethyl-2-pentylfuran by a new route. [3-14C]11-(5-Pentyl-3-methyl-2-furyl)undecanoate and [2-14C] 9-(5-pentyl-2-furyl)nonanoate were prepared from their lower homologs. The label was introduced in all cases by means of the Arndt-Eistert method for chain elongation, using14CH2N2. Comparisons of yields show that, with increasing number of substituents on the ring, the furan compounds are increasingly subject to uncontrollable side reactions.  相似文献   

10.
Long chain acyl-coA synthase (acsl) family genes activate the conversion of long chain fatty acids into acyl-coA to regulate fatty acid metabolism. However, the evolutionary characteristics, tissue expression and nutritional regulation of the acsl gene family are poorly understood in fish. The present study investigated the molecular characterization, tissue expression and nutritional regulation of the acsl gene family in golden pompano (Trachinotus ovatus). The results showed that the coding regions of acsl1, acsl3, acsl4, acsl5 and acsl6 cDNA were 2091 bp, 2142 bp, 2136 bp, 1977 bp and 2007 bp, encoding 697, 714, 712, 659 and 669 amino acids, respectively. Five acsl isoforms divided into two branches, namely, acsl1, acsl5 and acsl6, as well as acsl3 and acsl4. The tissue expression distribution of acsl genes showed that acsl1 and acsl3 are widely expressed in the detected tissues, while acsl4, acsl5 and acsl6 are mainly expressed in the brain. Compared to the fish fed with lard oil diets, the fish fed with soybean oil exhibited high muscular C18 PUFA contents and acsl1 and acsl3 mRNA levels, as well as low muscular SFA contents and acsl4 mRNA levels. High muscular n-3 LC-PUFA contents, and acsl3, acsl4 and acsl6 mRNA levels were observed in the fish fed with fish oil diets compared with those of fish fed with lard oil or soybean oil diets. High n-3 LC-PUFA levels and DHA contents, as well as the acsl3, acsl4 and acsl6 mRNA levels were exhibited in the muscle of fish fed diets with high dietary n-3 LC-PUFA levels. Additionally, the muscular acsl3, acsl4 and acsl6 mRNA expression levels, n-3 LC-PUFA and DHA levels were significantly up-regulated by the increase of dietary DHA proportions. Collectively, the positive relationship among dietary fatty acids, muscular fatty acids and acsl mRNA, indicated that T. ovatus Acsl1 and Acsl3 are beneficial for the C18 PUFA enrichment, and Acsl3, Acsl4 and Acsl6 are for n-3 LC-PUFA and DHA enrichment. The acquisition of fish Acsl potential function in the present study will play the foundation for ameliorating the fatty acids nutrition in farmed fish products.  相似文献   

11.
The CI-(CH4) mass spectra of the methyl esters and the EI mass spectra of the oxazoline derivatives of three cyclopropenoid fatty acids (malvalic, sterculic and α- hydroxy-sterculic acid) from the seed oil ofPachira aquatica were found to be useful for structure elucidation of such compounds. Furthermore, some hitherto unknown minor fatty acids were identified and the nuclear magnetic resonance data of the oil and α-hydroxysterculic acid methyl ester are presented.  相似文献   

12.
This paper describes the preparation of C19 dicarboxylic acid by the Koch reaction with carbon monoxide and sulfuric acid of oleic, tall oil fatty, and partially hydrogenated tall oil fatty acids. The effects of changing reaction conditions upon the yield and purity of the product were examined. With the best conditions, it was possible to prepare light-colored, heat-stable C19 dicarboxylic acid in 83% overall weight yield at 96% purity, containing 75% tertiary isomers and 25% secondary.  相似文献   

13.
S. Q. Alam  B. M. Bergens  B. S. Alam 《Lipids》1991,26(11):895-900
The effect of dietary n−3 fatty acids on prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) levels in rat salivary glands and gingiva was examined in two separate nutritional studies. In the first set of experiments, two groups of male weanling Sprague-Dawley rats were fed semipurified diets containing 10% corn oil (control group) or 10% menhaden oil (experimental group). Rats were killed after 8 wk on the diets; the fatty acid composition of total phospholipids and the concentrations of PGE2 and its precursor, arachidonic acid, were measured in gingiva and submandibular salivary glands (SMSG). Dietary n−3 fatty acids were incorporated into the tissue phospholipids. Arachidonic acid levels were reduced by 56% in gingiva and SMSG of rats fed menhaden oil compared with the control rats fed the diet containing corn oil. The concentrations of PGE2 in SMSG and gingiva of rats fed the diet containing menhaden oil were reduced by 74% and 83%, respectively. In a subsequent nutritional study, we tested whether the diet-induced reduction in tissue arachidonic acid levels would also result in a corresponding decrease in LTC4 production. Three groups of rats were fed diets containing 5% corn oil (group 1), 4% ethyl ester concentrate of n−3 fatty acids plus 1% corn oil (group 2), or 5% ethyl ester concentrate of n−3 fatty acids (group 3). After 6 wk of feeding, gingiva and SMSG were analyzed for arachidonic acid content andin vitro production of LTC4. Arachidonic acid content of total phospholipids was about 60% lower in gingiva and 69% lower in SMSG of rats fed the ethyl ester concentrate of n−3 fatty acids (groups 2 and 3) than those of the control group fed the corn oil diet (group 1). Upon incubation with calcium ionophore, gingiva and SMSG from rats fed the n−3 fatty acids rich diet produced significantly less TLC4 than those from rats of the control group. Because PGE2 and LTC4 are believed to be important biochemical mediators of periodontal disease, one may speculate that a diet-induced reduction in their levels may have a beneficial effect upon the course of the disease. The function of salivary glands may also be altered because of the role of these eicosanoids in salivary secretions. Presented in part for the Hatton Award Competition at the American Association for Dental Research Meeting, San Francisco, California, March 15–19, 1989, and at the International Association for Dental Research Meeting, Acapulco, Mexico, April 17–21, 1991.  相似文献   

14.
Minor constituents in high quality tall oil fatty acids have been isolated successfully by liquid column chromatography, using silicic acid as the adsorbent. The minor constituents contained two types of compounds: those which were noneffective and those which were effective in causing the darkening of tall oil fatty acids during heating. The former consisted oftrans-3,5-dimethoxystilbene and rosin acids. The latter was separated into numerous fractions by the combination of chemical methods, silicic acid column chromatography, and low temperature fractional crystallization. The fractions were characterized by functional group analyses, chemical reactions, and UV and IR spectrometric methods. Most of the fractions contained two-three times as much oxygen in the molecule as the original sample and were highly oxidized fatty acids. They had mol wt ranging 300–551 and contained double bonds, carbonyl, ester, peroxide, and hydroxyl groups. The effect of these minor constituents upon the color stability of tall oil fatty acids during heating was postulated as being due to the hydroxyl groups located in the α-position to the double bond in the molecule.  相似文献   

15.
In the present investigation, the fatty acid profile was analysed in vegetative and reproductive parts of eight commercially cultivated Indian cultivars of Moringa oleifera and verified by gas chromatography mass spectra. In leaves, α-linolenic acid (C18:3, cis-9,12,15) was found in the highest quantity (49–59 %) followed by palmitic acid (C16:0) (16–18 %), and linoleic acid (C18:2, cis-9,12) (6–13 %). The total content of saturated fatty acids and unsaturated fatty acids showed a ratio of 0.33 (cv. DHANRAJ) to 0.39 (cv. PKM-2) in leaves, 0.53 in flowers and 0.56 in tender pods. Similarly, polyunsaturated fatty acids and total monounsaturated fatty acids were found in a ratio of 5.68 (cv. DHANRAJ) to 9.71 (cv. CO-1) in leaves, 1.11 in flowers and 2.79 in tender pods. The total lipid content was recorded in the range of 1.92 % (flowers) to 4.82 % (leaves, cv. CO-1). When considering health benefits, M. oleifera leaves contain low amounts of saturated fatty acids, a high mono- and polyunsaturated fatty acid content, which can enhance the health benefits of Moringa-based products.  相似文献   

16.
In this study, our aim was to enrich olive oil with stearidonic acid (SDA) together with polyunsaturated fatty acids (PUFA) by lipase-catalyzed acidolysis using olive oil (OO) and free fatty acids of Echium oil, in the presence of Lipozyme? TL IM. The reaction conditions were optimized by using response surface methodology. A three-factor, five level central composite circumscribed designs was used to generate the design points. The factors chosen were: substrate molar ratio (S r, 4–6?mol/mol), reaction temperature (T, 55–65?°C), and reaction time (t, 6–9?h). Targeted incorporation (5?%) of SDA into OO was achieved at substrate molar ratio of 6?mol/mol, 55?°C, and 8.4?h. Model verification performed under these conditions for mg- and g-scale production yielded SDA contents of 4.9 and 4.8?%, respectively. Moreover, it was observed that the structured lipid (SL) obtained under optimum conditions contained approximately 42?% oleic acid and 43?% PUFA including linoleic acid, α-linolenic acid, and γ-linolenic acid. Omega-6/omega-3 fatty acid ratio of SLs was 0.7. Analysis of oxidative properties resulted in lower oxidative stability of SL than unmodified OO. This type of SL containing SDA and other PUFA is believed to be beneficial for human health.  相似文献   

17.
Thirty percent of the fatty acids fromHeliophila amplexicaulis seed oil are hydroxy acids, primarily lesquerolic acid (14-hydroxy-cis-11-eicosenoic acid) with a trace of a new fatty acid, 16-hydroxy-cis-13-docosenoic acid. The hydroxy acids in the oil are found exclusively in the 1 and/or 3 positions of the triglycerides and are completely acylated with C20 or C22 saturated or monoenoic acids. 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   

18.
Supercritical CO2 extraction from microalgae is applied with the aim of obtaining an oil rich in α-linolenic (ALA) essential fatty acid and with a low ω6:ω3 ratio. The maximum extraction yield is obtained at 60 °C and 30 MPa with 0.4 kg/h of CO2 and 5% of co-solvent (ethanol). When the effect of pressure, temperature and density on the supercritical extraction yield and solubility are studied, the thermodynamic cross-over is found at a pressure close to 30 MPa, while the extraction cross-over occurs at around 25 MPa. The experimental solubility data are correlated by literature empirical models. Mathematical models developed by Sovová are applied to describe the experimental extraction curves. Soxhlet extraction of lipids is also carried out, obtaining a similar fatty acids profile but proving to be less selective than SCCO2 method. Among the three species of microalgae examined, results show that Scenedesmus obliquus oil is richer in ω-3 fatty acids and ALA than Chlorella protothecoides and Nannochloropsis salina lipids. The effect of the extraction parameters on ALA content and the fatty acid profile is also analysed, concluding that the ω-3 percentage is favoured by lower temperatures, lower pressures and shorter extraction times.  相似文献   

19.
This work was dedicated to reporting the full chemical and physical characterisation of Crambe abyssinica Hochst. seed oil. The oil from the seeds was extracted using n-hexane. The seeds contain about 30?% oil. Density, refractive index, colour, smoke point, viscosity, acidity, saponification value, iodine value, fatty acid methyl esters, the relative position of fatty acids in C1 and C3 carbon glycerol, sterols, tocopherols, peroxide value, $ \mathop E\nolimits_{{1{\text{cm}}}}^{1\,\% } $ at 232?nm, and the susceptibility to oxidation measured by the Rancimat method were determined. The oil was found to contain high levels of unsaturated fatty acids, especially C22:1 (63.77?%). The dominant saturated acid was C22:0 (2.14?%). The oil was also found to contain high levels of β-sitosterol (51.93?%), campestanol (21.98?%), and brassicasterol (12.35?%). α-, γ-, and δ-Tocopherols were detected up to levels of 7.67, 125.04, and 3.99?mg/kg, respectively. The induction period (at 110?°C and 20?l/h) of the oil was 8.83?h. The relative position of fatty acids in C1 and C3 position was as follows: linoleic 0.45?%, oleic 8.84?%, and erucic 90.72?%. The thermal profile of the oil presented a single peak at ?20.94?°C.  相似文献   

20.
Hopkins CY  Chisholm MJ  Prince L 《Lipids》1966,1(2):118-122
Seed kernel oils of seven species of Lauraceae were examined and the fatty acid composition of six of these was determined. The oil ofLindera umbellata had 4% ofcis-4-decenoic, 47% ofcis-4-dodecenoic, and 5% ofcis-4-tetradecenoic acid in the total fatty acids. Positive identification of these acids was made and new derivatives were prepared. Possible routes of biosynthesis are discussed. Oils from the other species did not contain more than a trace of unsaturated C10−C14 acids. Their major acids were capric and lauric with varying amounts of unsaturated C18 acids. Issued as NRC No. 8928. Presented at the AOCS Meeting, Cincinnati, October 1965.  相似文献   

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