Fatty linoleate, linolenate

FIG. 23-36 Product compositions of tbe first-order sequence of fatty acids Linolenic Linoleic Oleic Stearic. 

More than LOO different fatty acids are known, and about 40 occur widely. Palmitic acid (C ) and stearic acid (Cjy) are the most abundant saturated fatty adds oleic and linoleic acids (both Care 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 because they have more than one double bond. Linoleic and linolenic... 

Fatty acids Linoleic, linolenic, oleic, palmitic, stearic... 

This conclusion is partly true because superoxide is unable to abstract hydrogen atom even from the most active bisallylic positions of unsaturated compounds, while perhydroxyl radical abstracts H atom from linoleic, linolenic, and arachidonic fatty acids with the rate constants of 1-3 x 1031 mol-1 s-1 [24], However, the superoxide damaging activity does not originate from hydrogen atom abstraction reactions but from one-electron reduction processes, leading to the formation of hydroxyl radicals, peroxynitrite, etc, and in these reactions perhydroxyl cannot compete with superoxide. 

The last essential dietary components to which we will refer and which were also discovered through feeding experiments with rats, are certain unsaturated fatty acids identified as linoleic, linolenic, and arachidonic acids by Burr and Burr in 1930. The acids are required for the formation of complex lipids which are essential in membranes for the maintenance of their fluidity (Chapter 9). Deficiencies lead to a dermatitis which does not respond to additional B vitamin supplements or to oleic acid. 

Studies are currently underway in Moscow on the suitability of using sodium caseinate nanoparticles as carriers for phosphatidylcholine (lecithin) containing > 80% unsaturated fatty acids (oleic, linoleic, linolenic). In particular, it has been established that phosphatidylcholine oxidation can be reduced, or effectively eliminated altogether, in dispersed systems containing complexes with the protein (see Figure 2.4). 

The conversion of oleoyl-CoA to linoleoyl-CoA is accomplished by some insects118 but does not take place in most animals. As a result of this biosynthetic deficiency, polyunsaturated fatty acids such as linoleic, linolenic, and the C20 arachidonic acid are necessary in the diet (Box 21-B). One essential function of linoleic acid is to serve as a precursor of prostaglandins and related prostanoids (Section D). Dietary linoleate is converted to its Co A derivative and then by sequential A6 desaturation,119 elongation, and then A5 desaturation, to the 20 4 (A5 8 11 14) arachidonoyl-CoA (Fig. 21-2, lower right). These acids are referred to as 0)6 because of the position of the last double bond. Linolenic acid can be converted in an analogous fashion to the CoA derivative of the 20 5 (A5 8 11 14 17 co6) eicosapentaenoic acid (EPA). The 22 6 docasahexaenoic acid (DHA Fig. 21-2) is apparently formed by elongation of the 22 5 acyl-CoA to 24 5, desaturation, transfer to a peroxisome or mitochondrion, and p oxidation to shorten the chain.953... 

Linoleic Acid Not less than 72% of total fatty acids. Linolenic Acid Not more than 1.5%. 

Lipoxygenase is highly specific and attacks the cis-cis-1,4-pentadiene group contained in the fatty acids linoleic, linolenic, and arachidonic, as follows ... 

F Essential fatty acids (linoleic, linolenic, and arachidonic acids)... 

Note Linoleic, linolenic, and arachidonic acids are called essential fatty acids by biochemists because such acids are necessary nutrients that are not synthesized in the animal body. 

Fatty acid epoxides have numerous uses. In particular, oils and fats of vegetable and animal origin represent the greatest proportion of current consumption of renewable raw materials in the chemical industry, providing applications that cannot be met by petrochemicals [64]. Polyether polyols produced from methyl oleate by the Prileshajev epoxidation (using peracetic acid) are an example. Epoxidized soybean oil (ESBO) is a mixture of the glycerol esters of epoxidized linoleic, linolenic, and oleic acids. It is used as a plasticizer and stabilizer for poly (vinyl chloride) (PVC) [1] and as a stabilizer for PVC resins to improve flexibility, elasticity, and toughness [65]. The ESBO market is second to that of epoxy resins and its world wide production... 

In the body processes, triglycerides or triacylglycerols are converted to the corresponding fatty acids, which in turn are nsed for energy or for other biochemical processes (LeBaron, in Devhn, 1986, p. 440fi0. Additionally, fatty acids can be synthesized in the body. Some fatty acids are considered essential, known by such names as palmitic, palmitoleic, stearic, oleic, linoleic, linolenic, and arachidonic. 

Addition of bromine to multiply unsaturated fatty acids such as linoleic, linolenic, and arachidic acid, is used for quantitative or approximate analysis of fatty acid mixtures.82... 

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