Highly unsaturated fatty acids

O. Geiger, E. P. Kennedy, V. N. Reinhold, and B. J. J. Lugtenberg, A novel, highly unsaturated fatty acid moiety of lipooligosaccharide signals determines host specificity of Rhizohium. Nature 354 125 (1991). 

We focused our attention on Tall oil, a by-product of the paper industry, whenever this is prepared according to the KRAFT process. Said material consists of a mixture of highly unsaturated fatty acids (many of which with conjugated diene systems) and terpene derived rosin acids. The rosin acids have the molecular formula C20H30O2 and thus belong to the diterpenes (pimaric and abietic acids). Tall Oil has an iodine number equal to approximately 170 gl2/100 g. 

Numerous studies demonstrated that lipid peroxidation significantly decreased in cancer cells and tissues (Ref. [176] and references therein). It has been proposed that this can be a consequence of a decrease in the content of highly unsaturated fatty acids, the concentration of cytochrome p-450, and the contents of NADPH, SOD, and catalase in tumors. Cheeseman et al. [176] suggested that the reduction of lipid peroxidation in tumors may depend on both the expression of malignant transformation and cell division. It should be mentioned that Boyd and McGuire [177] demonstrated that there is a correlation between lipid peroxidation and breast cancer risk in premenopausal women. 

It is commonly known that lipids, carbohydrates, and glycolipids are present in the Golgi apparatus (27). The determination of the components that react with the ZIO mixture was carried out by removing each component from tissues before incubation in the ZIO mixture. After lipid extraction by acetone (14), chloroform-methanol (15), or propylene oxide (27), no osmium-zinc precipitates could be detected in structures that normally reacted with ZIO. Blumcke et al. (15) summarized the nature of the lipids that react with the ZIO mixture as follows lipids and lipoproteins of cell membranes, neutral fat droplets (41), and lipid globules of type II pneumocytes and alveolar macrophages were, however, not as electron dense as the normally reactive lamellae containing highly unsaturated fatty acids. 

Hosokawa, M., Sato, A., Ishigamori, H., Kohno, H., Tanaka, T., and Takahashi, K. (2001). Synergistic effects of highly unsaturated fatty acid-containing phosphatidylethanolamine on differentiation of human leukemia HL-60 cells by dibutyryl cyclic adenosine monophosphate, jpn. ]. Cancer Res. 92, 666-672. 

The milk fats from marine mammals contain high levels of long-chain, highly unsaturated fatty acids, presumably reflecting the requirement that the lipids of these species remain liquid at the low temperatures of their environments. 

NOTE In general, antioxidants (e.g., TBHQ), are required when extracting oils that contain highly unsaturated fatty acids with 3, 4, 5, or 6 double bonds. 

In experimental assay systems, free fatty acids (FFAs) destroy red blood cells and show hemolytic activity (39). Free fatty acids, especially the highly unsaturated fatty acids (HUFAs) contained in the raphidophyte flagellates, have been implicated as one of the causative substances that damage the epithelial tissues of the fish gills. 

Kanazawa, A., Teshima, S. and Ono, K. (1979). Relationship between essential fatty acid requirements of aquatic animals and capacity for bioconversion of linolenic acid to highly unsaturated fatty acids. Comparative Biochemistry and Physiology 638,295-301. 

Takeuchi, T. and Watanabe, T. (1976). Nutritive value of io-3 highly unsaturated fatty acids in pollock liver oil for rainbow trout. Bulletin of the Japanese Society of Scientific Fisheries 42,907-919. 

Cold properties of biodiesel are highly correlated to the fatty acid composition. Biodiesel with a high content of saturated fatty acids, such as that from palm oil and coconut oil, possesses poor cold flow properties. On the other hand, biodiesel with a high content of unsaturated fatty acids possesses better flow properties at lower temperatures. However, biodiesel from highly unsaturated fatty acids with more than two double bonds has combustion problems. Therefore, in some countries, the content of highly unsaturated fatty acid methyl esters in biodiesel is kept low (5). 

Contains large amounts of even more highly unsaturated fatty acids. 

Shen, Z. and Wijesundera, C. 2006. Evaluation of ethanolysis with immobilized Candida antarctica lipase for regiospecific analysis of triacylglycerols containing highly unsaturated fatty acids. /. Am. Oil Chem. Soc., 83, 923-927. 

Docosahexaenoic acid (DHA) is a long-chain highly unsaturated fatty acid that is abundant in fish oil and is a precursor of several eicosanoids. DHA has a lipid-lowering effect through the suppression of lipogenic gene expression in the liver of rodents (Ikeda et al., 1998 Park and Harris, 2003 Buckley et al., 2004). In this paper, we introduce the evaluation of the physiological function of DHA in diet-induced lipodystrophy model mice. 

The glycerophosphatides usually contain substantial amounts of highly unsaturated fatty acids that undergo rapid autoxidation catalyzed by Cu2+ or Fe3+ salts. These salts tend to be carried along by lipids into the organic phase. Thus, lipid extractions may have to be made in a nitrogen atmosphere in the cold and may require the use of peroxide-free solvents or antioxidants. 

Highly Unsaturated Fatty Acids Arachidonic acid (AA) C20 4 0)6 C20 4A 5.8.11.14 cA-jCW-jCA-jCW-S,8,11,14-Eicosatetraenoic acid... 

Figure 1 Fatty acid synthesis in mammals. Gene encoding enzymes are shown in italics and are based on current evidence for substrate specificities. (A) De novo fatty acid synthesis. (B) Synthesis of the highly unsaturated fatty acids AA, EPA, and DHA from Cl 8 2 oo3 and Cl 8 3 m3 obtained from the diet. Details are found within the text.

Phosphatidylcholine contained the highest amount of unsaturated fatty acids, mostly oleic and linoleic acids. The other two principal phospholipids were rich in palmitic, linoleic, and linolenic acids. The presence of highly unsaturated fatty acids in phospholipids is important as they are prone to oxidation and can cause accelerated deterioration of the oil. It was also reported that phospholipids have a tendency to complex heavy metals, and these complexes are a stable form of catalyst, which can initiate and stimulate oxidation (28). 

The stability of canola oil is limited mostly by the presence of linolenic acid, chlorophyll, and its decomposition products and other minor components with high chemical reactivity, such as trace amounts of fatty acids with more than three double bonds. These highly unsaturated fatty acids can possibly be formed during refining and bleaching (52). The presence of 7% to 11% of linolenic acid in the acylglyce-rols of canola oil places it in a similar category with soybean oil with respect to flavor and oxidative stability. The deterioration of flavor as the result of auto -and photo-oxidation of unsaturated fatty acids in oils and fats is referred to as oxidative rancidity. 

The fatty acid composition of marine lipids varies significantly, especially when compared with vegetable oils. The fatty acid composition of blubber oil of marine mammals is generally similar to fish oils as it contains a large proportion of long-chain highly unsaturated fatty acids. However, the proportion of fatty acids in fish and marine mammals varies considerably (2). 

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