Docosahexaenoic acid fraction

It is well established that dietary (n-6) and (n-3) LCP modulate Thl and Th2 immune cell responses generation in the adult (Calder and Grimble, 2002). Docosahexaenoic acid (DHA) and arachidonic acid (AA) constitute a relatively small fraction of the total fatty acids in human breast milk, but have recently been suggested to participate in immime development... 

Hashimoto M., Hossain S., Agdul H., and Shido O. (2005). Docosahexaenoic acid-induced amelioration on impairment of memory learning in amyloid /i-inluscd rats relates to the decreases of amyloid fi and cholesterol levels in detergent-insoluble membrane fractions. Biochim. Biophys. Acta Mol. Cell Biol. Lipids 1738 91-98. 

Hills, M. J., Kiewitt, I., and Mukherjee, K. D. 1990. Enzymatic fractionation of fatty acids enrichment of y-linolenic acid and docosahexaenoic acid by selective esterification catalyzed by lipases. /. Am. Oil Chem. Soc., 67, 561-564. 

Several methods have been proposed to produce polyunsaturated fatty acid (PUFA) concentrates particularly high in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Most PUFA enrichment methods are based upon a combination of techniques such as saponification, solvent extraction, urea fractionation, molecular distillation, fractionation distillation, liquid chromatography, and super critical carbondioxide extraction. Current evidence suggests that the physiological effects of omega-3 fatty acids are such that the annual world supply of fish oils will be grossly inadequate as a source of these materials, and alternative sources will be needed (Belarbi et al, 2000). 

Supercritical fluid carbon dioxide (SC-CO2) fractionation of fish oil ethyl esters (EE) was employed to prepare EE of two omega-3 fatty acids, all cis-5,8,11,14, 17-eicosapentaenoic acid (EPA) and all cis-4,7,10,13, 16,19-docosahexaenoic acid (DHA) in 90% purity and to separate the synthetic triacylglycerols (TG), trieicosapentaenoylglycerol (tri-EPA), and tridocosahexaenoyl-glycerol (tri-DHA) in > 92% purity from other reaction mixture components. In the synthesis, glycerine reacted with EE and sodium glyceroxide catalyst to form TG. 

Vidgren, H.M., Agren, J.J., Schwab, U., Rissanen, T., Hanninen, O. and Uusitupa, M.I. (1997) Incorporation of n-3 fatty acids into plasma lipid fractions, and erythrocyte membranes and platelets during dietary supplementation with fish, fish oil, and docosahexaenoic acid-rich oil among healthy young men. Lipids. 32 697-705. 

The fatty acid composition of muscle lipids may show quantitative alterations in diseased muscle. Thus lecithin isolated from human dystrophic muscle had an increased amount of oleic but diminished linoleic acid (Tl). Changes have been recorded also in the fatty acid composition of lecithin from denervated muscle (PI). Recently it has been reported (K16) that the fatty acid pattern of muscle phosphatides from patients with the autosomal dominant form of myotonia congenita differed markedly from that of the autosomal recessive form and from the normal. Tani and his co-workers (F7) have made a detailed study of the phospholipids of normal and dystrophic mouse tissues. In normal mice phosphatidylcholine and phosphatidylethanolamine from skeletal and heart muscles had a very high content of 20-22-carbon polyunsaturated acids, in comparison with those for other tissues the most abundant was docosahexaenoic acid. In dystrophic mice there was a sharp decrease in the proportion of docosahexaenoic acid in the phosphoglycerides from skeletal and heart muscles, suggesting the likelihood of important alterations in muscle membranes. Somewhat similar studies have been reported by Owens (05), who also observed a fall in the proportion of docosahexaenoic acid, mainly in the phosphatidylcholine -j- choline plasmalogen fraction. 

Figure 4.20 NMR spectra of egg lipids (a) DHA egg oil (b) phosphatidylcholine fraction of DHA egg oil (c) phosphatidylethanolamine fraction of DHA egg oil. DHA = 4,7,10,13,16,19- docosahexaenoic acid. Instrument details are given in text. Section 4.10.

The following SPE sorbents have been reported for sample preparation prior to TLC analyses Cg chemically bonded silica gel in the TLC profiling of impurities in MDMA synthesis from piperonal " amino-bonded silica for fractionation of lipid classes" and recovery of lipids from Gaucher and Krabbe s disease patient tissue Cig silica gel for drugs in river water, resveratrol and piceid in wine, " and evolved alachlor collected in ethylene glycol " AgNOg-modified silica gel for determination of docosahexaenoic acid in bovine milk SBD-1 (styrene divinyl benzene) for organophosphorus pesticides in water " and Horisil for two oxycholesterols in raw and cooked meat. ... 

Hagashidate, S., Yamauchi, Y., and Saito, M. (1994) Fractionation of eicosapentaenoic acid and docosahexaenoic acid esters from esterified fish oil by coupled supercritical fluid extraction-chromatography, in M. Saito, Y. Yamauchi, and T. Okuyama (eds.). Fractionation by Packed Column SFC and SFE, VCH Publishers, New York, NY, USA, pp. 191-203. 

Receptor-mediated, guanosine 5 -triphosphate (GTP) protein-dependent signal transduction, initiated by stimulation of cholinergic M, receptors or dopaminergic D2 receptors, can activate PLAi to release arachidonate and/or docosahexaenoate from the sn-2 position of phospholipids (Axelrod et al., 1988 DeGeorge et al., 1991 Jones, Aral, Bell, Rapoport, 1996 Jones, Aral, Rapoport, 1997). This is illustrated for arachidonate in Fig. 4, which also shows that unlabeled arachidonic acid that is liberated by PI. A, into the brain unesterified pool can be rapidly labeled by tracer arachidonate injected into plasma (Grange et al., 1995 Washizaki et al., 1994). A fraction of the unesterified... 

FIGURE 1.21 Effect of initial molar ratio of various fatty acid esters to a-CD on the inclusion fraction of fatty acid esters in a-CD. O CAPME, A CPRME, MYRME, <> LINME, V EPAEE, DHAEE. Abbreviations CAPME, -caproic acid methyl ester CPRME, n-caprylic acid methyl ester LINME, linoleic acid methyl ester EPAEE, ethyl eicosapentae-noate DHAEE, ethyl docosahexaenoate. (From Yoshii, H. et ah, Oyo Toshitsu Kagaku, 42, 243, 1995. With permission.)... 

The types of CFAMs in heated fish oils include C20 and C22 acids of unknown structure, derived from eicosapentaenoate and docosahexaenoate, respectively, together with those from Cl8 fatty acids (Sebedio and De Rasilly, 1993). An adaptation of the described HPLC method (Fig. 5.17 Sebedio et al, 1994) included additional fractions between 18 0 and 20 0 and between 20 0 and 22 0 (using 19 0 and 21 0 as internal standards) encompassing C20 and C22 CFAMs, respectively. 

Eicosapentaenoic add (Table 6) is easily incorporated into the cell membrane-bound phospholipids. It is a poor substrate for the cyclooxygenase/hydroper-oxidase enzymatic system, and only very small amounts of endproducts with three double bonds will be formed when compared with the relative effectiveness of arachidonate metabolism. In contrast, dcosapentaenoic add is a preferred substrate for product generation by the S-lipoxygenase in subcellular fractions of human and animal neutrophils [66,87], whereas docosahexaenoic add is also a markedly inferior substrate for leukotriene synthesis. Eicosapentaenoic acid appears to inhibit phospholipase activity, resulting in a decrease of aradiidonic acid release ([67] Fig. 4). Moreover, simultaneously with thromboxane A3 and prostaglandin I3 generation from eicosapentaenoic add, the synthesis of thromboxane A2 and prostacyclin (PGIj) from aradiidonic acid [47] decreases, mainly due to inhibitory effects on PGH synthase activity (Fig. 4). 

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