Triunsaturated fatty acids

Mono-, di-, and triunsaturated fatty acids are named with Arabic numeral locants for the unsaturated positions and with the suffix -enoic, -adienoic, and -atrienoic acid in place of the -ane ending of the saturated hydrocarbon name, eg, 10,12,14-octadecatrienoic acid. 

Modulation of the quantity and/or quality of poly(3HAMCL) synthesized in peroxisomes was also achieved by modifying the endogenous fatty acid biosynthetic pathway [58]. For example, expression of the peroxisomal PHA synthase in an A. thaliana mutant deficient in the synthesis of triunsaturated fatty acids [59] resulted in the synthesis of a PHA having an almost complete absence of triunsaturated 3-hydroxyacid monomers [58]. In a different strategy, expression of a fatty acyl-ACP thio esterase in the plastid was combined with the expression of a peroxisomal PHA synthase [58]. Fatty acyl-ACP thioesterases are... 

Clarity at or below ambient room temperature is the primary characteristic of a liquid oil. Natural vegetable oils that are liquid at room temperatures in temperate climates, 75 5°F (23.4 3°C), contain high levels of unsaturated fatty acids with low melting points. Fatty acids with one or more double bonds and 18 carbon atoms are the most important unsaturated fatty acids for liquid oils. Oleic (18 1), a monounsaturated fatty acid, is the most widely distributed and most stable Ci8 unsaturated fatty acid. Linoleic (18 2) and linolenic (18 3) are the most widely distributed di- and triunsaturated fatty acids. Both of these polyunsaturated fatty acids are termed essential because they cannot be synthesized by animals, including man, and must be supplied in the diet. Complete exclusion of the essential fatty acids from the diet results in scaly skin, loss of weight, kidney lesions and eventually death. 

Triunsaturated fatty acids normally dominate chloroplast membranes and thus are the most abundant fatty acids on the planet. By constructing a triple mutant of fadS, fad , and fads, it has been possible to eliminate triunsaturated fatty acids from Arabidopsis without affecting 16 2 and 18 2 production (M. McConn, 1996). Surprisingly, these plants are able to grow, photosynthesize, and even flower. However, they are male sterile and therefore cannot produce seeds. This observation led to the discovery of a very different... 

UUU - Triunsaturated Fatty Acids VLDL - Very-Low-Density Lipoprotein. 

Several forms with 16,18 and 20 carbon atoms were identified in archaeological pottery vessels and were presumed to have been generated during heating triunsaturated fatty acids. They were used as biomarkers to trace the ancient processing of marine animal in these vessels. 

In sharp contrast to animals, few plants only contain y-linolenic acid (octadeca-A6,9,12-trienoic acid) as triunsaturated fatty acid the major triunsaturated fatty acid in plants is usually a-linolenic acid. The oil of the common borage (Borago officinalis L.) seed is one of the most abundant plant soiirce of rlinolenic acid (Stymne and Stobart, 1986). After several experiments to improve the in vitro A6- and A 12-desaturation assays with respectively (l-l C)linoleoyl-CoA and (l-l C)oleoyl-CoA, we optimized the conditions for in vitro incubation (Galle et al., 1993). From studies on A6-desaturase of rat liver microsomes (Okayasu etaL, 1981), we supposed that in plant, the A6-desaturase belongs to the same enzymatic complex as A12-desaturase. 

The flavour of distillates from apple and pear is characterised by typical aroma compounds from these fruits formed by enzymatic degradation of fatty acids to C6-fragments like hexanol, trans-2-hexenol, as well as ethyl esters and acetates of hexanoic acid. In distillates of pears, especially of the variety Bartlett pear, the characteristic pear flavour is mainly dominated by the ethyl and methyl esters of frans-2-czs-4-decadienoic acid and trans-2-trans-A-decadienoic acid [27-29], The biogenesis of these monounsaturated, diunsaturated, and triunsaturated esters may be explained by -oxidation of unsaturated linoleic and linolenic acid in the fruits. The sesquiterpene compound a-farnesene, which is formed during postharvest ripening and storage of Bartlett pears [28], shows that quality and intensity of distilled pear spirits is mainly influenced by the quality and degree of ripeness of the fruits. 

Tall oil is used as a source of turpentine. Tall oil fatty acids are mostly normal C18 acids, 75% mono- and diunsaturated, with lesser amounts of saturated and triunsaturated constituents. Tall oil is also used for waterproofing agents, dimer acids, polyamide resins for printer s ink, adhesives, detergents, and agricultural emulsifiers. 

Another question is whether it matters how the fatty acids are grouped together in TG that have the same fatty acid composition at each stereospecific position, e.g., a physical or interesterified mixture (by mole) of a 50% trisaturated and 50% triunsaturated mixture. For glycerides in general, it can be asked whether TG have the same effects as DG and MG and whether the isomeric structure of the partial glycerides (sw-l,2-DG, sn-l,3-DG or 5 -2,3-DG and 5M-1-MG, 5 -2-MG or sn-3-MG) matters. Finally, it can be asked whether fatty acids fed as TG have the same effects as the same fatty acids fed as phospholipids (PL). 

From substrate specificity studies (23,24), it seems that DS5 hydratase hydrates a specific carbon position of the unsaturated fatty acid substrates. To clarify this point and the effect of substrate carbon chain length on the strain DS5 hydratase activity, we studied the hydration of mono-, di-, and triunsaturated C-18 fatty acids as well as other carbon chain length monounsaturated fatty acids. 

The most abundant type of cell associated fatty acids are triunsaturated. 

A triunsaturated 16 carbon chain (16 3) is >5% of the cell fatty acids. 

The basic concept involves the essentially simultaneous polymerization by independent routes of epoxidized triglycerides (in this case linseed, crambe, and lesquerella oils) and styrene to make simultaneous interpenetrating networks. A typical commerical epoxidized linseed oil is considered to have the average structure described in structure (1). Crambe and lesquerella oils differ in that the corresponding fatty acids have the following compositions crambe 57% C (monounsaturated), and 32% C (mono-, di-, and triunsaturated) and lesquerella, 70% C q (-0H... 

Independently of stress degree, the percentages of saturated fatty acids, such as palmitate, stearate, oleate and linoleate decrease, while those of triunsaturated acids increased. Under salt stress and at all plant ages, linolenic acid rate was reduced weakly and that of hexadecatrienoic acid decreased significantly, in parallel levels of saturated fatty acids increased. 

For all studied species of Hexactinellida, the cumulative percentages of A5,9 polyimsaturated fatty adds are particularly high. No fatty acid with 27 carbon atoms has been identified A5,9,% triunsaturated fatty adds have been found with chains of 28, 29, 30, 31 and 32 carbon atoms. 

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