Saturated fatty myristic acid

Although vegetable oils usually contain a higher proportion of nnsatnrated fatty acids than do animal oils and fats, several plant oils are actually high in saturated fats. Palm oil is low in polyunsaturated fatty acids and particularly high in (saturated) palmitic acid (whence the name palmitic). Coconut oil is particularly high in lanric and myristic acids (both saturated) and contains very few nnsatnrated fatty acids. 

Most of the technically produced a-sulfo fatty esters are prepared from unbranched saturated fatty acid esters that are derived from 8 22 carboxylic acids and Cj-C3 alcohols. In particular the C12 (lauric), C14 (myristic), C16 (palmitic), and C18 (stearic) acids are interesting because the ester sulfonates... 

Laurie, myristic, palmitic, and stearic fatty acids make up most of the saturated fatty acids found in fats. Oleic acid, linoleic acid, and linolenic acid are the most abundant unsaturated fatty acids found in oils. 

Figure 11.1 Structures of commonly occurring saturated fatty acids (i) myristic acid, Ci4 o (ii) palmitic acid, C s-.o (iii) stearic acid, Ci8 0.

The traditional major source for the nonionic surfactant industry is fatty acid triglycerides from both animal and vegetable sources as the saturated or unsaturated acids. The saturated acids include lauric acid (w-dodecanoic), myristic acid (n-tetradecanoic), palmitic acid ( -hexadecanoic),and stearic acid (n-octadecanoic). The unsaturated acids include oleic acid (Z-9-octadecenoic) and linoleic acid (Z,Z-9,12-octadecadienoic). Of the 200 non-ionic surfactants... 

Saturated fatty acids (no double bonds), such as myristic, palmitic, and stearic, make up two-thirds of milk fatty acids. Oleic acid is the most abundant unsaturated fatty acid in milk, with one double bond. Triglycerides account for 98% of milk fat. The small amounts of mono-, diglycerides, and free fatty acids in fresh milk may be... 

N-Myristoylation is achieved by the covalent attachment of the 14-carbon saturated myristic acid (C14 0) to the N-terminal glycine residue of various proteins with formation of an irreversible amide bond (Table l). 10 This process is cotranslational and is catalyzed by a monomeric enzyme called jV-myri s toy 11ransferase. 24 Several proteins of diverse families, including tyrosine kinases of the Src family, the alanine-rich C kinase substrate (MARKS), the HIV Nef phosphoprotein, and the a-subunit of heterotrimeric G protein, carry a myr-istoylated N-terminal glycine residue which in some cases is in close proximity to a site that can be S-acylated with a fatty acid. Functional studies of these proteins have shown an important structural role for the myristoyl chain not only in terms of enhanced membrane affinity of the proteins, but also of stabilization of their three-dimensional structure in the cytosolic form. Once exposed, the myristoyl chain promotes membrane association of the protein. 5 The myristoyl moiety however, is not sufficiently hydrophobic to anchor the protein to the membrane permanently, 25,26 and in vivo this interaction is further modulated by a variety of switches that operate through covalent or noncovalent modifications of the protein. 4,5,27 In MARKS, for example, multiple phosphorylation of a positively charged domain moves the protein back to the cytosolic compartment due to the mutated electrostatic properties of the protein, a so-called myristoyl-electrostatic switch. 28 ... 

Another application concerns the solid residue in a pilgrim flask of the third century A.D. from the Rhineland, which was also referred to us by Robert H. Brill. About 70% of the material was soluble in carbon tetrachloride, and its NMR spectrum (Figure 7) immediately identified it as a mixture of saturated fatty acids (and their soluble salts) with an average chain length of 14 to 16 carbon atoms, corresponding to myristic and palmitic acids. This average molecular weight was obtained by... 

Saturated Fatty Acidsb Myristic acid ch3(ch2),2co2h 14 0... 

It is important to bear in mind when discussing the effect of dairy fat in association to heart disease that dairy products contain many different saturated fatty acids that do not exert the same biological response in terms of, for example, cholesterol levels. The saturated fatty acids in milk fat include shorter and medium chain fatty acids (2 0-10 0), lauric acid (12 0), myristic acid (14 0), palmitic acid (16 0), and stearic acid (18 0). Other fatty acids in milk fat are oleic acid (18 1) and linoleic acid (18 2n-6) as indicated in Table 1.2. 

Palmitic and stearic acids are the major saturated fatty acid constituents of most animal and plant tissues. Much smaller amounts of other saturated fatty acids are present in most natural sources. Low concentrations of myristic acid (n-tetradecanoic acid 14 0) and lauric acid (n-dodecanoic acid 12 0) have been detected in certain tissues. 

Jojoba (Simmondsia chincnsis) This is not actually an oil but a liquid wax. It is good for cosmetic use with moisturizing properties and ideal for dry skin and conditions like eczema and psoriasis. It is similar chemically to sebum and able to dissolve it. The oil keeps well owing to a stable molecular structure and analysis shows both saturated and unsaturated fatty acids, with eicosenoic (71%), oleic (14%), stearic (10%) and palmitic (1.5%). The presence of a compound called myristic acid is thought to confer anti-inflammatory properties. 

The saturated fatty acid tctradccanoic acid (also known as myristic acid) is manufactured commercially from coconut oil by base-catalysed hydrolysis. You may be surprised to learn that coconut oil contains more saturated fat than butter, lard, or beef dripping much of it is the trimyristate ester of glycerol. Hydrolysis with aqueous sodium hydroxide, followed by reprotonation of the sodium carboxylate salt with acid, gives myristic acid. Notice how much longer it takes to hydrolyse this branched ester than it did to hydrolyse a methyl ester (p. 291),... 

It is now known that not all saturated fatty acids are equally hypercholesterole-mic. For example, medium-chain saturated fatty acids of carbon length 8-10, as well as stearic acid (18 0), have little or no effect on serum cholesterol concentrations. In contrast, evidence indicates that palmitic acid (16 0), the principle fatty acid in most diets, can increase serum cholesterol concentrations in humans. However, in normocholesterolemic humans, dietary palmitic and oleic acids have been shown to exert similar effects on serum cholesterol, suggesting that only humans or animal species sensitive to dietary cholesterol and selected fats ( hyperresponders ) may exhibit significant changes in semm cholesterol in response to dietary fat intake. Myristic acid (14 0) and, to a lesser extent, lauric acid (12 0), which are relatively high in coconut oil, both can raise serum cholesterol and LDL-cholesterol levels. Overall, it is not clear why humans respond so differently to cholesterol or... 

Saturated fatty acids. The adverse effect of saturated fat on blood cholesterol level and its implication in cardiovascular disease has stimulated concern over the level of saturated fatty acids in the diet. Canola oil contains a very low level (<7%) of saturated fatty acids about half the level present in corn oil, olive oil, or soybean oil and about one-quarter the level present in cottonseed oil. Furthermore, canola oil contains only 4% of the saturated fatty acids (viz., lauric, myristic, and palmitic) that have been found to increase blood cholesterol level. Hence, canola oil fits well with the recommendation to reduce the amount of saturated fat in the diet. 

The basic fish oil (27) also included a generous amount of saturated fatty acids. As can be seen from Figure 5 and Table 1, the saturated fatty acids are dominated by the 16 0 (palmitic acid), usually accompanied by about half as much or less of 14 0 (myristic acid) and much less of 18 0 (stearic acid). Usually the saturated fatty acid totals are at least 20%, especially as the odd chain (15 0, 17 0) and methyl-branched (iso, anteiso, pristanic, phytanic) fatty acids (compare Figure 4) are sam-rated and will total around 2-3%. An unsaturated peak that is often observed is 17 ln-8, which is roughly equal to 17 0. The details of these peaks are discussed in other publications, but those researchers attempting modern open-tubular gas chromatography analyses should be aware of their presence and influence on peak identification and quantitation. As can be seen from Figure 6, there is an... 

Palmihc add (16 0) iS the primary saturated fatty acid in most diets. This compound constitutes about 25% of the fatty acids of beef or pork fat, but only 6-10% of Ihc fatly acids of sunflower, safflower, peanut, or soy oils (see Table 6.8). Dietary palmitic add increases LDL-cholesterol (Grundy and Denke, 1990), Myrislic acid (14 0) is present at high levels in butter fat and in the "tropical oils" palm oil and coconut oil. Although myristic add elevates LDL-cholesterol, it is generally a rather minor component of the diet. Stearic acid (18 0) is also a major component... 

Diets rich in saturated fat provoke an increase in LDL-cholesteroi, increase TGs, and lower HDl cholcstcrol — these diets worsen all three risk factors. Ilris statement applies to the saturated fatty acids 12 0 (lauricacid), 14 0 (myristic acid), and 16 0 (palmitic acid). In realizing the tendency of these three fatty acids to provoke cardiovascular disease, a question often asked is, "Should we replace the saturated fats in the diet with other saturated fatty acids (such as stearic acid 1 8l0), with fats containing monounsaturated fatty acids (such as oleic acid 1S 1), w ith fats con-... 

As previously mentioned, the triglycerides found in biomass are esters of the triol, glycerol, and fatty acids (Fig. 3.6). These water-insoluble, oil-soluble esters are common in many biomass species, especially the oilseed crops, but the concentrations are small compared to those of the polysaccharides and lignins. Many saturated fatty acids have been identified as constituents of the lipids. Surprisingly, almost all the fatty acids that have been found in natural lipids are straight-chain acids containing an even number of carbon atoms. Most lipids in biomass are esters of two or three fatty acids, the most common of which are lauric (Cn), myristic (Cu), palmitic (Cia), oleic (Cis), and linoleic (Cis) acids. Palmitic acid is of widest occurrence and is the major constituent (35 to 45%) of the fatty acids of palm oil. Lauric acid is the most abundant fatty acid of palm-kemel oil (52%), coconut oil (48%), and babassu nut oil (46%). The monounsaturated oleic acid and polyunsaturated linoleic acid comprise about 90% of sunflower oil fatty acids. Linoleic acid is the dominant fatty acid in com oil (55%), soybean oil (53%), and safflower oil (75%). Saturated fatty acids of 18 or more carbon atoms are widely distributed, but are usually present in biomass only in trace amounts, except in waxes. 

The simplest and most common synkinons are non-branched, saturated fatty acids from C12 to C18 (trivial names lauroyl Cl2, myristoyl Cl4, palmitoyl or cetyl Cl 6, stearoyl Cl8) and their sodium, ammonium and potassium salts (also known as soaps ). Laurie, myristic, palmitic and stearic acids are barely soluble in water at 20°C (5.5, 2.0,0.7 and 0.3 mg/L) and 60°C (8.7, 3.4, 1.2 and 0.5 mg/L), each ethylene group lowering the solubility by a factor of 2-3. The solubilities of the corresponding sodium and potassium salts are, however, in the order of several grams per litre. Even in highly concentrated emulsions of soaps in distilled water ( 30% w/w), precipitation of solids is often not observed. Bivalent fatty acid salts, however, are just as insoluble as free fatty acids only 1.4 mg of calcium stearate dissolves in 1 L of water. ... 

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