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31.
32.
33.
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
34.
35.
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
36.
37.
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
38.
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
39.
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
40.