Polyunsaturated fatty acid esters

Alkio, M., Gonzales, C., Jantii, M., and Aaltonen, O. 2000. Purification of polyunsaturated fatty acid esters from tuna oil with supercritical fluid chromatography. Journal of the American Oil Chemists Society, 77 315-21. 

We have achieved good separation of polyunsaturated fatty acid esters from saturated, monosaturated and disaturated fatty acid esters and this has been used as a means of identifying the presence of polyunsaturates, especially fish oil, in samples (Fig. 1.2). However, if there is a considerable amount of trienoic fatty acids in the mixture, as in egg lipids, the separation is not very pronounced (Shantha and Ackman, 1991a). Nakamura, Fukuda and Tanaka (1996) have used similar TLC separation of marine lipids and were able to quantitate the amount of pol)amsaturated fatty acids by using scanning densitometry followed by Coomassie blue staining. 

Polyunsaturated fatty acid esters from sardine oil Ag+ ELM TR + R Nanoka and Kawamoto (1996)... 

Metathesis of polyunsaturated fatty acid esters, such as methyl linoleate and methyl linolenate, leads to a variety of reaction products, including polyenes, monoesters, diesters and cyclopolyenes [10],... 

Many plants contain polyunsaturated fatty acid esters in their leaves or seeds, as do the foods derived from these plants. Such structures are prone to autoxidation that gives hydroperoxides leading to lower molecular... 

Polyunsaturated fatty acid/ester (Section 23.2) A fatty acid or... 

The cathodic solution prepared by the electrolysis of an NaCl solution showed a strong antioxidant activity on flie aqueous oxidation of polyunsaturated fatty acid esters, squalene, vitamin A and P-carotene. Although the mechanism for the antioxid t effect of the cathodic solution has not been fully elucidated, the effect would be partly due to radical scavenging ability and/or alkaline molecules formed in the cathodic solution. On the other hand, the antioxidant activity of the cathodic solution has not been found on phosphatidylcholine, free fatty acids and a-tocopherol. The different effect of the cathodic solution on the oxidation of polar lipids may be correlated witii the ionization of these lipids in the cathodic solution. 

The intermediate m hydrogenation formed by reaction of the unsaturated ester with the hydrogenated surface of the metal catalyst not only can proceed to the saturated fatty acid ester but also can dissociate to the original ester having a cis double bond or to its trans stereoisomer Unlike polyunsaturated vegetable oils which tend to reduce serum cholesterol levels the trans fats produced by partial hydrogenation have cholesterol raising effects similar to those of saturated fats... 

Polyunsaturated fatty acids in vegetable oils, particularly finolenic esters in soybean oil, are especially sensitive to oxidation. Even a slight degree of oxidation, commonly referred to as flavor reversion, results in undesirable flavors, eg, beany, grassy, painty, or fishy. Oxidation is controlled by the exclusion of metal contaminants, eg, iron and copper addition of metal inactivators such as citric acid minimum exposure to air, protection from light, and selective hydrogenation to decrease the finolenate content to ca 3% (74). Careful quality control is essential for the production of acceptable edible soybean oil products (75). 

Dahle, L.K., Hill, E.G. and HoUman, RT. (1962). The TBA reaction and the autoxidation of polyunsaturated fatty acid methyl esters. Arch. Biochem. 98, 253-259. 

The lipase-catalyzed fatty acid ester hydrolysis and the lipoxygenation of free polyunsaturated fatty acids are involved in the same lipid degradation pathway. They are respectively the first and second reaction in the lipoxygenase pathway (Fig. 3) [87-91]. The pathway produces volatile products of considerable importance in food technology including Cg[92, 93] or Cg- 94—96 aldehydes and alcohols from polyunsaturated fatty... 

Linoleic acid is a polyunsaturated fatty acid (compound containing two or more double bonds) occurs as an ester in polyunsaturated fats. 

Keough, T. Mihelich, E.D. Eickhoff, D.J. Differentiation of Monoepoxide Isomers of Polyunsaturated Fatty Acids and Fatty Acid Esters by Low-Energy CE-MS. Anal. Chem. 1984,56, 1849-1852. 

Gorreta, F., Bernasconi, R., Galliani, G., Salmona, M., Tacconi, M. T., and Bianchi, R. (2002). Wax esters of co-3 polyunsaturated fatty acids A new formulation as a potential food supplement—Digestion and absorption in rats. Lebensmittel-Wissenschaft und Technologie 35,458-465. 

Another example is afforded by fibrate drugs and phthalate esters, which bind to the PPAR, in mimicry of polyunsaturated fatty acids. 

Lipoxygenase (EC 1.13.11.12) is an enzyme that catalyzes the hydroperoxidation of polyunsaturated fatty acids and esters containing a cis-cis-l, 4-pentadiene system (Table 6). In 1947, Theorell et al. obtained the enzyme in a crystalline form from soybeans and reported that the enzyme neither contained nor required a metal cofactor192. Subsequent studies from three groups of investigators have demonstrated that the enzyme purified from soybeans in an iron-containing dioxygenase74-76 ... 

Hydrocarboxylation of Polyunsaturated Fatty Acids and Esters with a Palladium Chloride— Triphenylphosphine Complex Catalyst... 

The chromatographic profiles representing saturated mono-, di-, and polyunsaturated long-chain fatty acid esters from marine triacylglycerols were very complex. In general, polyunsaturates are eluted before saturates of equal chain length and shorter-chain before longer-chain fatty acid esters. 

The simplest class of lipids are FAs. This group includes various types of fatty acids, eicosanoids, fatty alcohols, fatty aldehydes, fatty esters, fatty amides, fatty nitriles, fatty ethers, and hydrocarbons. Many FAs, especially the eicosanoids derived from n-6 and n-3 polyunsaturated fatty acids, have... 

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