Palmitic add

Many of the ingredients used in pyrot compns, fuels/oxidizers, are sensitive to moisture. Most oxidizers are hygroscopic, ie NaNOj, NH4NO3, etc. Some fuels oxidize readily when exposed to moisture, ie, Mg, Fe, Al, etc. These materials have been protected with coatings of paraffin wax (Refs 20 41). Both stearic acid and stearin (mixt of stearic and palmitic adds) have been used to coat and protect Al from moisture... 

Palmitic acid is present as cetyl ester in spermaceti from which, by hydrolysis, the acid may be obtained it is present in bee s wax as the mehssic ester and in most vegetable and animal oils and fats, in greater or lesser amounts, as glyceryl tripalmitate or as mixed esters, along with stearic and oleic adds, Palmitic acid is separated from stearic and oleic acids by fractional vacuum distillation and by fractional crystallization. With NaOH, palmitic add forms sodium palmitate, a soap, Most soaps are mixtures of sodium stearate, palmitate, and oleate. 

Palmitic add finds use in the production of cosmetics, food emulsifiers, pharmaceuticals, plastics, and soaps. One commercial formulation contains 95% palmitic add, 4% stearic acid, and 1% myristic acid another preparation contains 50% palmitic acid and 50% stearic acid. 

Fatty add esters palmitic add butyl ester palmitic acid 2-ethylhexyl ester stearic acid 2-ethyhexyl ester dibutyl adipate. 

The synthesis of triacylglycerol takes place in the endoplasmic reticulum (ER). In liver and adipose tissue, fatty adds in the cytosol obtained from the diet or from de novo synthesis of palmitic add become inserted into the ER membrane. The reactions are shown in Fig. 13-10. Membrane-bound acyl-CoA synthetase activates two fatty acids, and membrane-bound acyl-CoA transferase esterifies them with glycerol 3-phosphate, to form phosphatidic acid. Phosphatidic acid phosphatase releases phosphate, and in the membrane, 1,2-diacylglycerol is esterified with a third molecule of fatty acid. 

The standard incubation mixture contained 100 fiL of 0.25 M Tris-HCl buffer (pH 7.4) containing 1.75 mM palmitic add and 1% (w/v) Tween-20 50 /x.L of enzyme preparation (about 0.5 mg protein), and 50 tL of 80 or 100 nM zinc acetate solution. After incubating 5 minutes at 37°C, the reaction was started by adding 50 / L of 100 /iM mesoporphyrin or protoporphyrin. The incubation was continued for 30 minutes at 37°C in the dark. The reaction was stopped by adding 1 mL of ice-cold methanol-DMSO (8 2, v/v) containing 13 nM Zn-deuteroporphyrin as internal standard. The mixture was cooled on ice and centrifuged before analysis of the supernate by HPLC. The... 

Figure 2.51 shows the structure of the 16-carbon fatty acid palmitic add. In the triglyceride and phospholipid structures shown in Figure 2,32, R, R, and represent the alkane "tails" of fatty adds. The fatty acid compositions of the phospholipids and triglycerides of various foods are listed in Table 2-2-...

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... 

Palmitic acid (16 0) is not much converted in the body to 16 .1. However, palmitic acid (16 0) is converted readily to 18 1 by the pathway shown in Figure 6.36. This conversion is much slower than that of dietary 18 0 to 18 1, and thus accounts for the LDL-cholesterol raising effect of palmitic add. 

The final step in fatty acid catabolism involves the attack of a molecule of coenzyme A at the 3fatty acid, resulting in the discharge of a two-carbon imit (acetyl group). The sole breakdown product of even-carbon-numbered fatty acids, such as palmitic add, is acetyl-CoA. A small fraction of the fatty adds encoimtered in the diet have an odd number of carbons. The catabolism of these fatty acids yields a number of molecules of acetyl-CoA plus one molecule of propionyl-CoA. 

Figure 6. K and R for palmitic add spread on the designated buffers (see text) and maintained at the designate 7r. IQ and R were mean values from at least five desorption experiments. R was estimated by measuring film contraction over the period t = 0to 1 min.

Pristerene. [Unidheina Unichema France SA] Stearic or palmitic adds intermediate for ediox ates, esters, nitrogen derivs., personal prod, formulations, sosp, detergents, std>ilizers, candles, paper chemicals, rubber, inorganic coatings, textile auxiliaries. 

Phytosterols Palmitic add Neophytadiene Polar fraction Alkaloids... 

Growth of rat cancer cells was also reduced by TTA. This suggests that cell lines from other species than human are sensitive to this siilfur substituted fatty acid analogue. Moreover, palmitic acid inhibited the proliferation of rat ghoma cells (BT4Cn) and human leukemic cells (HL-60). However, TTA was more potent. On the growth of hiunan breast cells, EPA was more potent than palmitic add. Evidently, cancer cells may be more... 

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