Eicosapentanoic acid

Molina Grima, E., Robles Medina, A., Gimenez Gimenez, A., and Ibanez Gonzalez, M. J. 1996. Gram-scale purification of eicosapentanoic acid (EPA, 20 5n-3) from wet Phaeodactylum tricornutum UTEX 640 biomass. 8, 359-367. J. Appl. Phycol., 8, 359-367. 

Aside from sophisticated drug design, there is a surprisingly simple means of favourably influencing the balance of Good and Evil in eicosanoid metabolism Eating fish. As initially mentioned, aside from arachidonic acid, other multiply non-saturated fatty acids can serve as precursors of eicosanoid mediators as well, in particular eicosapentanoic acid (EPA), which has an additional double bond between C17 and Cl8. The introduction of this omega-3 double bond does not occur, nor is it reversible, in mammalian... 

Figure 12.16. Omega-3 fatty acids and their relevance to prostaglandin metabolism, a Omega-3 nnsatnrated fatty acids are derived from linoleic acid by a special desatnrase fonnd in plants bnt not in mammals. They are particnlarly common in cold-waterfish. b The different nnmbers and positions of donble bonds persist in the eicosanoids derived from different fatty acid precnrsors, giving rise to different homologons derivatives. This is shown here for prostaglandin E. c Biological activity of the eicosanoids derived from eicosapentanoic acid (EPA).

The list of research studies goes on and on, all with favorable results. We now know that the main fish oils, eicosapentanoic acid (EPA) and docohexanoic acid (DHA), work in a number of wonderful ways. These omega-3 fatty acids reduce the formation of blood clots and raise levels of the protective HDL cholesterol while dramatically lowering triglycerides. They prevent heart rhythm disturbances and they lower heart rates. Because heart rate is associated with the risk of sudden death, this association may at least partially explain the lower risk of sudden death among people who regularly eat fish. 

Dietary intake of n-6 fatty acids such as linoleic acid, and n-3 fatty acids, such as the fish oils eicosapentanoic acid and docosahexaenoic acid, lowers plasma cholesterol and antagonizes platelet activation, but the fish oils are much more potent in this regard [26]. In particular, n-3 fatty acids competitively inhibit thromboxane synthesis in platelets but not prostacyclin synthesis in endothelial cells. These fatty acids have also been shown to have other potentially anti-atherogenic effects, such as inhibition of monocyte cytokine synthesis, smooth muscle cell proliferation, and monocyte adhesion to endothelial cells. While dietary intake of n-3 fatty acid-rich fish oils appears to be atheroprotective, human and animal dietary studies with the n-6 fatty acid linoleic acid have yielded conflicting results in terms of effects on both plasma lipoproteins and atherosclerosis. Indeed, excess amounts of both n-3 and n-6 fatty acids may actually promote oxidation, inflammation, and possibly atherogenesis (M. Toberek, 1998). In this context, enzymatic and non-enzymatic oxidation of linoleic acid in the sn-2 position of LDL phospholipids to 9- and 13-hydroxy derivatives is a key event in LDL oxidation (Section 6.2). 

Figure 2.1-13 Scheme of the continuous extraction of esters (eicosapentanoic acid (EPA)/docosahexanoic acid (DHA)) [51]. 

Extraction of Flavors, Aromas, and Colorants (1, 23, 24) Concentration of Eicosapentanoic Acid from Fish Oils (25-29) Extraction of Cholesterol from Butter, Lard, Tallow Eggs (30) Decaffeination of Coffee (31)... 

Cholesterol extraction studies listed in Tables I and II have progressed from the initial scale to an optimization phase at the laboratories of the University of Wisconsin and Phasex Corporation (35. Whereas all the applications listed in Table II are interesting for discussion, fish oils extraction and enzyme reactions were selected for their newness and/or novelty for discussion here. Fish oil extraction with supercritical fluids exhibits the potential to become the preferred separations process if high concentration levels of eicosapentanoic acid are required, and it is being in vestigated by many workers. The subject of enzyme reactions in supercritical fluids is, at present for the most part, an interesting academic pursuit but it exemplifies the breadth of application of supercritical fluid extraction. 

Figure 2. Extraction profile of eicosapentanoic acid from batch continuous extraction of menhaden oil ethyl esters. Extraction conditions 2200 psig, 40 °C, with a 100 °C heated zone above extractor. (Reproduced with permission from Ref. 38. Copyright 1988 American Oil Chemists Society.)...

The egg yolk of chickens fed the biomass of the red algae Porphyridicum sp., which constitutes a unique combination of soluble sulfated polysaccharide and polyunsaturated fatty acids (arachidonic acid and eicosapentanoic acid), tended to have reduced cholesterol (by 10%) (Ginzberg et al., 2000). 

Cohen, Z., Didi, S. and Heimer, Y.M. (1992) Overproduction of y-linolenic acid and eicosapentanoic acids by algae. Plant Physiol. 98, 569-572. 

Higdon, JV, Liu, J, Du, SH, Morrow, JD, Ames, BN and Wander, RC (2000) Supplementation of postmenopausal women with fish oil rich in eicosapentanoic acid and docosahexanoic acid is not associated with greater in vivo lipid peroxidation compared with oils rich in oleates and linoleate as assessed by plasma malondialdehyde and Fj-isoprostanes. Am J... 

Although not produced by the human body, these Essential Fatty Acids (EFAs) are required for normal brain function, growth, development, bone health, stimulation of skin and hair growth, regulation of metabolism, and maintenance of reproductive processes (University of Maryland Medical Centre, 2008). The health benefit provided by PUFAs is dependent on the precise PUFA being taken. The health benefits of the fish derived PUFAs eicosapentanoic acid and docosahexanoic acid are well described (Sanderson et al., 2002). There is interest in... 

Extracted arachidonic acid (14.5), docosanoic acid (38), eicosanoic acid (34), eicosatrienoic acid (17), eicosapentanoic acid (12), lauric acid (10), Unoleic acid (15.5), linolenic acid (12.5), gamma-linolenic acid (13), m5rristic acid (13), palmitic acid (18.5), patmitoleic acid (15), stearic acid (27), tetracosanoic acid (42)... 

Most of the clinical and experimental research that has investigated the effects of dietary fatty acids specifically on obesity and IR has focnsed on total fat or the effects of the fatty acid classes SFA, MUFA and PUFA. Some stndy has also been devoted to the very long-chain marine n-3 PUFA [eicosapentanoic acid (EPA) and docosapentanoic add (DHA)] but less is known about the plant-based n-3 PUFA, ALA. The study designs (controls, population, total amount of fat) and results vary but overall some consistent patterns with regard to fatty acid type can be extracted. 

Haraldsson, GG, BO Gudmundsson, 6 Aknarsson. (1993). The preparation of homogeneous triglycerides of eicosapentanoic acid and docosahexanoic acid by lipase. Tetrahedron Lett 34 5791-5794. 

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