Polyunsaturated fatty acids lipid content

A molecular variation of plasma membrane has been reported by Puccia et al. Reduction of total lipids (XL) content and significant variations of triglyceride (TG) and phospholipids (PL) fractions were observed as a consequence of exposure of C. intestinalis ovaries to TBTCl solutions. In particular, an evident TG decrease and a PL increase were observed, which probably provoked an increment in membrane fluidity, because of the high concentration of long chain fatty acids and, as a consequence, PL. This could be a cell-adaptive standing mechanism toward the pollutants, as observed in Saccharomyces cerevisiae. Also the increase in the content of the polyunsaturated fatty acids (PUPA), important in the synthesis of compounds such as prostaglandin which are present in the ovary in a stress situation, was probably a consequence of a defense mechanism to the stress provoked by the presence of TBTCl. 

Potatoes are not regarded as an important source of lipids, because the lipid content of the tuber is very low, ranging from 0.2 to 2 g (1.2 g on average) per kg on a fresh weight basis (OECD, 2002). The flesh of boiled potato cooked in skin without salt contains about 0.1 g total lipids, 0.03 g total saturated fatty acids, 0.002 g total monounsaturated fatty acids, and 0.043 g total polyunsaturated fatty acids per 100 g (USDA, 2007). The Adequate Intake determined for the essential n-6 and n-3 polyunsaturated fatty acids is for adults 11-17 and l.l-1.6g per day, respectively (Food and Nutrition Board, 2005). 

Major flaxseed sterols are stigmasterol, camp sterol, and 5-5 avenasterol (Daun et al., 2003). Obtusifoliol, gramisterol, and citrostadienol constituted 45%, 22%, and 12%, respectively, of the total 4a-monomethylsterol in flaxseed (Kamm et al., 2001). Squalene content of flaxseed oil was reported as 4 mg/100 g oil, which was significantly lower than olive, corn, and rice bran oils. Squalene content is an intermediate compound of biosynthesis of plant sterols, which may have protective effects on lipid quality. Squalene could act as a peroxy radical scavengers in high polyunsaturated fatty acid oil (Dessi et al., 2002). 

Adaptations to change in temperature involve not only the fatty acids in the phospholipids but may affect the proportions of different lipid fractions in the total lipids as well. Some workers (Shatunovsky, 1980 Lapin and Shatunovsky, 1981 van den Thillart and de Bruin, 1981 Sidorov, 1983) claim that a drop in temperature results in an increased proportion of phospholipids in the total lipids. There is a larger concentration of polyunsaturated fatty acids in the phospholipid fraction than in other lipid fractions. However, other workers (Anderson, 1970 Caldwell and Vembeig, 1970 Selivonchick and Roots, 1976 Wodtke, 1978 Hazel, 1979) have not found this effect, and Knipprath and Mead (1966) found that the phospholipid content of goldfish actually decreased during adaptation to cold. 

More recent work emphasizes the synthesis by the fish of polyunsaturated fatty acids in the marine environment. Borlongan and Benitez (1992) maintained groups of milkfish (which can tolerate salinities from 0 to 100%o) in fresh water or sea water on the same diet, and while the two groups showed no differences in their total lipid contents, the proportion of phospholipids in the lipids of various organs was the greater in fish from sea water. The organs of fish in fresh water contained lipids with higher proportions of neutral lipids. 

Answer The temperature of body tissues at the extremities, such as near the hooves, is generally lower than that of tissues closer to the center of the body. To maintain fluidity, as required by the fluid-mosaic model, membranes at lower temperatures must contain a higher percentage of polyunsaturated fatty acids a higher content of unsaturated fatty acids lowers the melting point of lipid mixtures. 

Ertas et al. (2005) investigated the potential effects of dietary supplementation by coriander seed (considered as a lipolytic and antioxidant compound) on carcass lipid composition of quails. Their aim was to reduce saturated fatty acid consumption and to increase essential fatty acids (particularly n3 unsaturated acids) in alimentation. Dietary supplementation by coriander seed affected the lipid composition of carcass greatly by decreasing saturated fatty acid (SFA) contents (palmitic and stearic acids) and by increasing monounsaturated and polyunsaturated fatty acid (MUFA and... 

Central nervous tissue appears to provide an especially avid environment for the occurrence of oxygen-radical generation and lipid-peroxidative reactions due to a high content of polyunsaturated fatty acids. There is now considerable biochemical, physiological and pharmacological data that supports such a connection between radical reactions and secondary CNS tissue injury. 

Abstract. The significance of free radical oxidation of phospholipids in tissues of animals with experimental atherosclerosis was investigated. By using modem physico-chemical methods an elevated content of polyunsaturated fatty acids and other lipids peroxides was discovered in the blood and the aorta of rabbits with experimental atheromatosis. The human blood demonstrated a low level of protective enzymatic systems and a high content of products secondary to peroxidal oxidation of the lipids. The mechanism accounting for the action of lipids peroxides on the vascular wall resulting in the formation of atheromatous plaques is considered. 

By feeding nutritionally adequate diets, dietary intake of 18 2n-6, 18 3n-3, or the proportion of 18 2n-6 to 18 3n-3, particularly during development, has been shown to influence the content of long-chain polyunsaturated fatty acids in membrane lipids by changing the composition of the whole brain, oligodendrocytes, myelin, astrocytes mitochondrial, microsomal, and synaptosomal membrane (Bourre et al., 1984 Foot et al., 1982 Lamptey Walker, 1976 Tahin et al., 1981). Feeding diets with a 18 2n-6 to 18 3n-3 fatty acid ratio between 4 1 and 7 1 to rats from birth to 1, 2, 3, and 6 wk of... 

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