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1.
In addition to the ω-5 olefinic acids found in otherGrevillea species, about 10% of the acyl groups ofG. decora seed oil contain a hydroxy group and an ω-5 double bond. The chainlengths of these acids are from C22 to C30, with the largest concentration at the C26 and C28 chainlengths. The hydroxy group is located on odd carbons from carbon-5 through carbon-13. These acids previously were unknown
in nature. The most abundant of these are 7-hydroxy-cis-17-docosenoic, 7-hydroxy-cis-19-tetracosenoic, 9-hydroxy-cis-19-tetracosenoic, 9-hydroxy-cis-21-hexacosenoic, 11-hydroxy-cis-21-hexacosenoic, and 13-hydroxy-cis-23-octacosenoic acids. The oil also contains the largest known concentration of the unoxygenated C26 and C28 ω-5 monoenes. 相似文献
2.
Cysteine reacts with linoleic acid hydroperoxide to yield several products, some of which were identified as fatty acid-cysteine
adducts. The addition was catalyzed by ferric chloride (10−5 M) by initiating free radical reactions. When isomerically pure 13-hydroperoxy-cis-9,trans-11-octadecadienoic acid and cysteine were reacted in 80% ethanol under N2, the major adducts were 9-S-cysteine-13-hydroxy-10-ethoxy-trans-11-octadecenoic acid (I) and 9-S-cysteine-10,13-dihydroxy-trans-11-octadecenoic acid (II). When the reaction included both isomers of the hydroperoxide (13-and 9-hydroperoxide) and air,
an adduct of 9-oxononanoic acid and cysteine also was isolated. Additional experiments gave information about possible mechanisms
of I and II formation. 相似文献
3.
Douglas G. Hayes Robert Kleiman 《Journal of the American Oil Chemists' Society》1995,72(11):1309-1316
Eight lipases were screened for their ability to synthesize estolides from a mixture that contained lesquerolic (14-hydroxy-11-eicosenoic)
acid and octadecenoic acid. With the exception ofAspergillus niger lipase, all 1,3-specific enzymes (fromRhizopus arrhizus andRhizomucor miehei lipases) were unable to synthesize estolides.Candida rugosa andGeotrichum lipases catalyzed estolide formation at >40% yield, with >80% of the estolide formed being monoestolide from one lesquerolic
and one octadecenoic acyl group:Pseudomonas sp. lipase synthesized estolides at 62% yield, but the product mixture contained significant amounts of monoestolide with
two lesquerolic acyl groups as well as diestolide. ImmobilizedR. miehei lipase was chosen to catalyze the esterification of mono-and polyestolide, derived synthetically from oleic acid, with fatty
alcohols or α,ω-diols. Yields were >95% for fatty alcohol reactions and >60% for diol reactions. In addition, the estolide
linkage remained intact through the course of the esterification process. Esterification of estolides improved the estolide’s
properties—for example, lower viscosity and higher viscosity index—but slightly raised the melting point. Estolides and, particularly,
estolide esters may be suitable as lubricants or lubricant additives. 相似文献
4.
A detailed investigation of the seed oil ofByrsocarpus coccineus Schum. and Thonn. has disclosedcis-11,12-methyleneoctadecanoic (lactobacillic) (13%) and two branched octadecenoic acids (0.1%). Other fatty acids in the oil
are those normally associated with seed lipids except for an unusually high proportion (12%) ofcis-11-octadecenoic acid. Lactobacillic acid has long been known as a constituent of certain bacterial lipids, but this is the
first report of its presence in a seed oil. The branched olefinic acids have not heretofore been found to occur in plants.
Mention of firm names or trade products does not imply endorsement or recommendation by the Department of Agriculture over
other firms or similar products not mentioned. 相似文献
5.
Robert Kleiman Kathleen L. Payne-Wahl 《Journal of the American Oil Chemists' Society》1984,61(12):1836-1838
The seed lipids of three species ofEntandraphragma (Meliaceae) contain the largest proportion (31–50%) ofcis-vaccenic acid ever found in nature. The acid is not indicative of the family as a whole and is found as a major fatty acid
in the seed of only one additional species, besidesEntandraphragma, out of the 30 analyzed from this family. With the total oil comprising between 45 and 62% ofEntandraphragma seed, these species should be considered as a source of undecadioic acid for the production of nylon 11. 相似文献
6.
Gayland F. Spencer Robert Kleiman 《Journal of the American Oil Chemists' Society》1978,55(10):689-689
Roureopsis obliquifoliata Schellenberg seeds contain an oil (45% by weight) comprised primarily of 16-carbon fatty acids. Palmitic acid constitutes
50% of the fatty acids, palmitoleic acid 32%, and small amounts of the usual C18 acids make up the remainder. Identifications were based on Chromatographic properties of the acids and their ozonolysis products. 相似文献
7.
Gayland F. Spencer Robert Kleiman 《Journal of the American Oil Chemists' Society》1978,55(11):837-838
The presence of spermaceti, an embargoed item, was confirmed in a sample of hand cream detained by federal agents. The identification
was based on chromatographic characteristics of the intact wax esters and of their component fatty acids and alcohols. These
acids and alcohols were combined in a manner so closely resembling spermaceti that they undoubtedly came from this source. 相似文献
8.
Portenschlagia ramosissima (Port.) vis. (Umbelliferae) seed contains 15% essential oils, 70% of which is the aromatic ether myristicin. These structural
assignments were made from nuclear magnetic resonance, combined gas chromatography-mass spectrometry (GC-MS), and infrared
and ultraviolet data. GC-MS data also indicate the presence of pinene, cymene, terpinene, elemicin, methyl eugenol, and a
variety of sesquiterpene hydrocarbons. 相似文献
9.
An isomeric mixture of linoleic acid hydroperoxides, 13-hydroperoxy-cis-9,trans-11-octadecadienoic acid (79%) and 9-hydroperoxy-cis-12,trans-10-octadecadienoic acid (21%), was decomposed homolytically by Fe(II) in an ethanol-water solution. In one series of experiments,
the hydroperoxides were decomposed by catalytic concentrations of Fe(II). The 10−5 M Fe(III) used to initiate the decomposition was kept reduced as Fe(II) by a high concentration of cysteine added to the
reaction in molar excess of the hydroperoxides. Nine different monomeric (no detectable dimeric) fatty acids were identified
from the reaction. Analyses of these fatty acids revealed that they were mixtures of positional isomers identified as follows:
(I) 13-oxo-trans,trans-(andcis,trans-) 9,11-octadecadienoic and 9-oxo-trans,trans- (andcis,trans-) 10,12-octadecadienoic acids; (II) 13-oxo-trans-9,10-epoxy-trans-11-octadecenoic and 9-oxo-trans-12, 13-epoxy-trans-10-octadecenoic acids; (III) 13-oxo-cis-9,10-epoxy-trans-11-octadecenoic and 9-oxo-cis-12, 13-epoxy-trans-10-octadecenoic acids; (IV) 13-hydroxy-9,11-octadecadienoic and 9-hydroxy-10,12-octadecadienoic acids; (V) 11-hydroxy-trans-12, 13-epoxy-cis-9-octadecenoic and 11-hydroxy-trans-9, 10-epoxy-cis-12-octadecenoic acids; (VI) 11-hydroxy-trans-12, 13-epoxy-trans-9-octadecenoic and 11-hydroxy-trans-9,10-epoxy-trans-12-octadecenoic acids; (VII) 13-oxo-9-hydroxy-trans-10-octadecenoic acids; (VIII) isomeric mixtures of 9, 12, 13-dihydroxyethoxy-trans-10-octadecenoic and 9, 10, 13-dihydroxyethoxy-trans-11-octadecenoic acids; and (IX) 9, 12, 13-trihydroxy-trans-10-octadecenoic and 9, 10, 13-trihydroxy-trans-11-octadecenoic acids. In another experiment, equimolar amounts of Fe(II) and hydroperoxide were reacted in the absence of
cysteine. A large proportion of dimeric fatty acids and a smaller amount of monomeric fatty acids resulted. The monomeric
fatty acids were examined by gas liquid chromatography-mass spectroscopy. Spectra indicated that the monomers were largely
similar to those produced by the Fe(III)-cysteine reaction.
Presented in part at the American Chemical Society Meeting, Los Angeles, March 1974.
ARS, USDA. 相似文献
10.
Thirty-six lots of eightCuphea species grown at nine geographical locations from 1983 to 1985 were analyzed for seed weight, oil percentage, fatty acid
and crude protein content. Twenty-two samples were separated into two distinct seed maturity groups and also analyzed. Seed
maturity varied widely but had little effect on oil percentage, even though mature seeds were significantly heavier than less
mature seeds. Lauric acid content generally increased and capric acid decreased with increasing seed maturity. Crude protein
of whole seeds and defatted seed meal increased with increasing seed maturity. The net effect of harvestingCuphea wrightii seeds at full maturity in comparison with that for less mature seeds was to increase seed weight by 12%, decrease capric
acid by 3%, increase lauric acid by 2% and increase crude protein of whole seeds and defatted meal by 5% and 4%, respectively.
Seed oil content was decreased by a statistically nonsignificant 1%. The effect of seed maturity was comparable for the other
four lauric acid- and three capric acid-rich species, even though distinct species differences in all factors were measured.
Location and environment contributed to some quantitative and qualitative changes, but these factors are not considered to
be major sources of variation. It is concluded that variation in seed maturity does not present a major constraint to commercialization
ofCuphea as a new, alternative source of lauric and other medium-chain fatty acids. The ultimate significance of these minor changes
will depend upon relative yields, demands and values of the various seed components. 相似文献