PUFA’s

It is important to note that saturated fatty acids are not immune to effects of oxidation. The strongly oxidizing radicals HO and RO abstract hydrogens at reasonable rates even from saturated fatty acids (10 for RO and 10 for HO ). The subsequent LsatOO radicals then abstract hydrogens from neighboring unsaturated fatty acids and thus can be sources of external radicals initiating radical chains in PUFA s (9, 208). 

More than 100 different fatty acids have been identified about 40 of them occur widely. Palmitic acid (Cjg) and stearic acid (Cig) are the most abundant saturated fatty acids oleic and linoleic adds (Cj ) are the most abundant unsaturated ones. Oleic acid is monounsaturated since it has only one double bond, whereas linoleic, linolenic, and arachidonic acids are polyunsaturated fatty acids, or PUFA s, because they have more than one double bond. Linoleic and linolenic acids occur in cream and are essential in the human diet infants grow poorly and develop skin lesions if fed a diet of nonfat milk for prolonged periods. 

We read a lot about the relationship between cholesterol and heart disease. What are the facts It s well established that a diet rich in saturated animal fats often leads to an increase in blood serum cholesterol, at least in sedentary, overweight people. Conversely, a diet lower in saturated fats and higher in polyunsaturated fats (PUFA s) leads to a lower serum cholesterol level. Studies have shown that a serum cholesterol level greater than 240 mg/dL (a normal value is 120-200 mg/dL) is weakly correlated with an increased incidence of atherosclerosis, a form of heart disease in which cholesterol deposits build up on the inner walls of coronary arteries, blocking the flow of blood to the heart muscles. 

Chamock, J.S. (1 1) Omega-3 and omega-6 PUFA s have different effects on the phospholipid fatty acid composition of rat myocardial muscle when added to a saturated fatty add dietary supplement. Nutr. Res. 11, 1013-1024. 

Rhodophyceae or red algae have high levels of 20C polwnsaturated lds (PUFA s) but usually very low levels of 16C PUFA s. There... 

Light stimulated [-acetate Incorporation into C. crlspus about 5-fold and Into P. lanosa about 3-fold. The distribution of radio-label between the C. crlspus fatty acids with and without Illumination is shown In Table 1. Illumination Increased the relative rate of synthesis of 18 lw.9 and 18 2w.6 but decreased that for 14 0, 16 0 and 18 0 and Is thus In agreement with other studies . Only occasionally were trace amounts of label found In the 20C PUFA s after 24h Incubations, Indicating a slow turnover rate of these, quantitatively very Important acids. P. lanosa showed a similar pattern. 

Other studies describe similar beneficial effects for PUFA-enriched diets to treat Crohn s disease, other inflammatory bowel diseases such as ulcerative colitis, as well as psoriasis, asthma, systemic lupus erythematosus, and multiple sclerosis [57], Thus, immunomodulation by PUFAs appears to be a promising intervention for the treatment of many autoimmune and inflammatory diseases. 

Qian, S. Y., Wang, H. P., Schafer, F. Q., and Buettner, G. R., 2000, FPR detection ofhpid-derived free radicals from PUFA, LDL, and cell oxidations. Free Radio. Biol. Med 29 568-579. 

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. 

Cabanes, A., Wang, M., Olivo, S., Gustafsson, J., and Hilakivi-Clarke, L. (2003). Effect of n-3 polyunsaturated fatty acids (PUFAs) on breast cancer progression. Cancer Epidemiol. Biomarkers Prev. 12 (1305S). 

Lipids are susceptible to oxidation and, therefore, analytical protocols are required to measure their quality. Not all lipids have the same degree of susceptibility to oxidation. Many factors are responsible for a lipid s tendency to oxidize, including the presence of catalysts, oxidative enzymes, radiation, and a lipid-air interface, as well as the oxygen partial pressure, the incorporation of oxygen into the product, and the presence of metal ions. The most important factor is the degree of unsaturation of the lipid itself. The majority of a food product s polyunsaturated fatty acids (PUFAs) are generally contained in phospholipids, which are consequently more prone to autoxi-dation than the triacylglycerol fraction. 

PTFE polytetrafluoroethylene PUFA polyunsaturated fatty acid PV peroxide value PVDF polyvinylidene difluoride PVP polyvinylpyrrolidone PVPP polyvinylpolypyrolidone RAS retronasal aroma stimulator RDA recommended dietary allowance RF radio frequency RFI relative fluorescence intensity RI retention index RNU relative nitrogen utilization ROESY rotational nuclear Overhauser enhancement spectroscopy RP-HPLC reversed-phase HPLC RPER relative protein efficiency ratio RS resistant starch RT retention time RVP relative vapor pressure S sieman (unit of conductance)... 

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). 

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