Linoleic acid unsaturated fatty acids effects

Cobalt in Driers for Paints, Inks, and Varnishes. The cobalt soaps, eg, the oleate, naphthenate, resinate, Hnoleate, ethyUiexanoate, synthetic tertiary neodecanoate, and tall oils, are used to accelerate the natural drying process of unsaturated oils such as linseed oil and soybean oil. These oils are esters of unsaturated fatty acids and contain acids such as oleic, linoleic, and eleostearic. On exposure to air for several days a film of the acids convert from Hquid to soHd form by oxidative polymeri2ation. The incorporation of oil-soluble cobalt salts effects this drying process in hours instead of days. Soaps of manganese, lead, cerium, and vanadium are also used as driers, but none are as effective as cobalt (see Drying). 

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). 

Hou, C. T. 2005. Effect of environmental factors on the production of oxygenated unsaturated fatty acids from linoleic acids by Bacillus megaterium ALA2. Appl. Microbiol. Biotechnol., 69,463—468. 

Figure 9. Effect of free long-chain saturated and unsaturated fatty acids on the total activity of non-selenic glutathione S-transferase from porcine liver (substrate - 1 mM 1-chloro-2,4-dinitrobenzene). Enzymatic activity was measured in the presence of follow free fatty acids fl) myristic (Cu o) (2) palmitic (C16 0) (3) stearic (C g o) (4) linoleic (Cigo) and (5) arachidonic (C20 4) - ( ) The first figure is the number of carbon atoms, and the second figure is the number of double bonds in the molecule of fatty acid [33],...

Offer, N.W., Marsden, M., Dixon, J., Speake, B.K., and Thacker, F.E. 1999. Effect of dietary fat supplements on levels of n-3 poly-unsaturated fatty acids, trans acids and conjugated linoleic acid in bovine milk. Anim. Sci. 69, 613-625. 

C chemical shifts of stearic, oleic, linoleic, a-linolenic and arachidonic acids have been assigned (Stoffel et al., 1972) and the data are presented in Table 21. Electric field effects associated with the dipolar head groups have been shown to be effective in influencing the 1 3C chemical shifts of unsaturated fatty acids (Batchelor et al., 1973). This electric field effect (Horsley and Sternlicht, 1968, McFarlane, 1970), predicted to be linear and dependent on distance and orientation, can be applied to problems of conformational analysis. A nondestructive technique utilizing l3Cnmr to determine the relative concentrations of the unsaturated fatty acids present in soyabeans has recently been developed (Schaefer and Stejskal, 1974). 

More drastic oxidation of the ethylenic bonds of oleic, linoleic, and similar unsaturated fatty acids causes the action to go beyond the formation of oxygenated groups and to result in rupture of the bond as well as in oxidation. Such agents as the dichromates, permanganates, and nitric acid may be used to obtain the effect. Thus, oleic, dihydroxystearic, and sterolic acids yield azelaic and pelargonic acids, products that may be further oxidized if the reaction is forced. 

The melting points of unsaturated fatty acids are lower than those of saturated fatty acids with the same number of carbons (compare stearic, oleic, linoleic, and linolenic acids in Table 19-1). The more double bonds present, the lower the melting point of the fatty acid. The effect of a double bond in lowering the melting point is a consequence of its presence in nature in the cis geometry instead of trans. Unsaturated fatty acids are liquids at temperatures where saturated fatty acids are solids. 

Brenner, R.R., and Peluffo, R.O. (1966) Effect of Saturated and Unsaturated Fatty Acids on the Desaturation In Vitro of Palmitic, Stearic, Oleic, Linoleic and Linolenic Acids, J. Biol. Chem. 241,5213-5219. 

In animals, certain unsaturated fatty acids, such as linolenic or linoleic acids, are essential dietary components. Whether these compounds can be synthesized by man has not been determined, but since they are widely present in fats ordinarily consumed, deficiency seems an unlikely possibility. In dogs, there is evidence for a need of fat above that necessary to relieve specific effects of essential fatty acid deficiency (Chapter 7). This may be true in other species, including man. 

The cod liver oil proved to be the critical component of the diet. Substitution by com oil made the diet nontoxic, and crude linoleic acid was approximately as effective. The eclamptic disease could be prevented by treating the animals with a-tocopherol or lettuce before the toxic diet was given, or by adding these materials to the eclamptogenic diet. Apart from a possible toxic effect of the vitamin D, it is also possible that the oil itself has a toxic effect. It is known that highly unsaturated acids are present which do not have the activity of the essential unsaturated fatty acids, because they have cis-trans and trans-trans configurations instead of the active cis-ds form. Even deficiency of the essential unsaturated fatty acids may be promoted. The crude linoleic acid, which was not quite as active as corn oil, may contain about 50% of the inactive cis-trans configura-tion(s). The vitamin E content of the com oil is probably important also. 

Biological activity of vitamin E is related to antioxidant effects the most effective antioxidant in vivo) is a-tocopherol. In food lipids, the situation is more compHcated, because the antioxidant activity of tocopherols and tocotrienols depends on many factors. One important aspect is the amount and composition of unsaturated fatty acids. Under typical storage conditions, tocopherols are more effective antioxidants, for example, in animal fats (the main fatty acid is oleic acid) compared with vegetable oils that contain higher amounts of linoleic acid (e.g. soybean and sunflower oils). 

So far Group B agents appear to specifically act on XDH, although studies of other enzymes may reveal additional effects. Group C contains representative steroid hormones which induce or suppress levels of XDH and in one case (hydrocortisone) induces an increase in tyrosine transaminase. Group D contains unsaturated fatty acids including oleic, linoleic and linolenic acids. These agents suppress levels of XDH and PNP. 

FIGURE 3-7 Pathways for the interconversion of brain fatty acids. Palmitic acid (16 0) is the main end product of brain fatty acid synthesis. It may then be elongated, desaturated, and/or P-oxidized to form different long chain fatty acids. The monoenes (18 1 A7, 18 1 A9, 24 1 A15) are the main unsaturated fatty acids formed de novo by A9 desaturation and chain elongation. As shown, the very long chain fatty acids are a-oxidized to form a-hydroxy and odd numbered fatty acids. The polyunsaturated fatty acids are formed mainly from exogenous dietary fatty acids, such as linoleic (18 2, n-6) and a-linoleic (18 2, n-3) acids by chain elongation and desaturation at A5 and A6, as shown. A A4 desaturase has also been proposed, but its existence has been questioned. Instead, it has been shown that unsaturation at the A4 position is effected by retroconversion i.e. A6 unsaturation in the endoplasmic reticulum, followed by one cycle of P-oxidation (-C2) in peroxisomes [11], This is illustrated in the biosynthesis of DHA (22 6, n-3) above. In severe essential fatty acid deficiency, the abnormal polyenes, such as 20 3, n-9 are also synthesized de novo to substitute for the normal polyunsaturated acids. 

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