And PUFAs

Facciotti, D. Metz, J.G. Lassner, M. (1998) Polyketide synthesis graes of marine microbe and production of polyunsaturated fatty acids and PUFA-containing plant oils with transgenic plants. PCT Int. Appl. 10 Dec. to Calgene LLC Co) Chem. Abstr., 1999,130, 62050. 

Patnayak, S. and Sree, A. (2005). Screening of bacterial associates of marine sponges for single cell oil and PUFA. Lett. Appl. Microbiol. 40,358-363. 

The other important property affecting lipid oxidation is the chelating effect of chlorogenic acids. It is important to keep in mind that the influence of biometals (Fe, Cu etc.) on lipid free radical oxidation is essential. It is well known that iron can react with hydrogen peroxide by the Fenton reaction (Equation 3). The hydroxyl radical formed in the Fenton reaction is capable of reacting with lipid and PUFA as the initiation stage. Iron can also participate in alkyl peroxide or lipid peroxide decomposition. Therefore, the nature of iron chelation in a biological system is an important aspect in disease prevention. 

Figure 9.17 Distribution of major fatty acids ( xg fatty acids L-1 and xg fatty acid mg-1 OC) in particulate organic matter (POM), very high molecular mass dissolved organic matter (VHDOM) (30 kDa-0.02 xm), and high molecular mass DOM (HDOM) (1-30 xm) in Delaware Bay estuary. Bacterial fatty acids (FA) included branched and normal saturated acids and 15 1A4 and PUFA = polyunsaturated fatty acids. (Modified from Mannino and Harvey, 1999.)...

Therefore, the cis-tmns isomerization mechanism in PUFA was revisited.The reactions were initiated by continuous °Co y-irradiation of NjO-saturated terf-butanol solutions containing j8-mercaptoethanol or benzenethiol and PUFA esters. Product studies led to a proposed detailed mechanistic scheme (Scheme 2). 

PUFAs are potent inhibitors of the HMG-CoA reductase enzyme and similar to statins are useful in the treatment of hyperlipidemias (99-102). Statins enhance plasma AA levels and decrease the ratio of EPA to AA significantly (100). This finding suggests that PUFAs mediate many actions of statins (103) and that this could be one mechanism by which they lower cholesterol levels. Statins and PUFAs have many overlap actions such as the inhibition of IL-6 and TNF-a production and NF-kB activation plus the ability to enhance eNO production thus, both possess anti-inflammatory actions and both are useful in atherosclerosis, coronary heart disease, osteoporosis, stroke, Alzheimer s disease, and inflammatory conditions such as lupus and cancer (3, 4, 94, 104-121). These similar and overlap actions strongly indicate that the molecular mechanisms of actions of statins and PUFAs are similar, if not identical. Furthermore, when a combination of statins and PUFAs are given together, a synergistic beneficial effect was seen in patients with combined hyperlipemia (122). 

The feeding of soybean lecithin to cold-water fish and cold-water cmstaceans— as a source of choline, inositol, ethanolamine, and PUFA—has been promoted in recent years. Levels as high as 7-8% of diet dry weight have been recommended (40, 41). 

In the event that polyunsaturates are foimd to be the best source of fat, with the goal of reducing atherosclerosis, then safflower oil may be the oil of choice. Presently, it is recommended to replace saturated fats with a mixture of fats containing monounsaturates and PUFAs. One can see, for example, that at least 80% of the fatty acids of com oil, canola oil, soybean oil, olive oil, and safflower oil occur as the recommended fatty acids (monos and PUFAs). 

What about the choices between carbohydrates, monounsaturated fatty acids, and PUFAs Studies on monounsaturated fatty acids versus carbohydrates have shown that monounsaturated fatty acids provoke a decrease in plasma TGs and an increase in HDL-cholesterol, with not much difference in effect on LDL-cholesterol. Studies on PUFAs versus carbohydrates have revealed that PUFAs result in lower LDL-cholesterol, with not much difference in effect on plasma TGs or HDL-cholesterol. 

The next study is purely chemical in nature and concerns the relationship between vitamin E and PUFAs. The study traces the breakdown of PUFAs over time. Layers of linoleic acid were placed in dishes. One dish contained a layer consisting only of linoleic acid (, Figure 9.107). Another dish contained a mixture of linoleic acid and vitamin E, with one molecule of vitamin E per 2(X)0 molecules of the fatty acid (-0—). A third dish contained a greater proportion of vitamin E, one molecule of vitamin E per 400 molecules of linoleate (—O—). The dishes were stored in air for 9 hours and samples taken at the times indicated in Figure 9.107. The results show the protective effect of vitamin E. Damage to the PUFA commenced immediately where the layer did not contain the vitamin. The damage was delayed where increasing concentrations of the vitamin had been included. 

Solvent extraction ( countercurrent distribution ) Separation of neutral lipid classes and PUFA from saturated FFA Readily scaled up, but poorly selective... 

Hibbeln JR, Enstrom G, Majchrzak S, Salem N Jr, Traskman-Benz L. Suicide attempters and PUFAS lower plasma eicosapentaenoic acid alone predicts greater psychopathology. 4th Congress of the International Society for the Study of Lipids and Fatty Acids, 2000, p. 191. 

Elongases (marked s on Fig. 1.1) and PUFA desaturases (marked A6 and A5 on Fig. 1.1) are not usually classified as lipogenic enzymes. However, they play a critical role in the synthesis of a variety of fatty acids either by acting on endogenously produced fatty acids (from lipogenesis) or on exogenous (dietary) fatty acids. Therefore, we chose to briefly introduce these enzymes. 

Fig. 2. Synthesis of saturated and n - 9 series of MUFA and PUFA by desaturation and elongation from dietary and de novo synthesized palmitate. FAS, fatty acid synthase.

Elovl-2 (formerly denoted as Ssc2) is involved in the biosynthesis of the n - 3 and n - 6 series of highly unsaturated fatty acids (HUFA). Expression studies in yeast demonstrated that Elovl-2 is able to efficiently elongate 20- and 22-carbon PUFA but is unable to elongate 18-carbon SFA, MUFA, and PUFA. Elovl-2 is predominantly expressed in the testis, a tissue in which HUFA are synthesized in high levels (A. Leonard, 2(X)2). 

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