Palmitic acid ethyl ester

Fig. 9.1.6. El mass spectrum of palmitic acid ethyl ester (12) (TIC retention time 18.94 min, Scan No. 1145) from GC-MS analysis...

Figure 9.1.6 shows the mass spectrum of palmitic acid ethyl ester (12) (TIC retention time 18.94min, Scan No. 1145). The major MS fragmentation patterns of the compound are similar to those of palmitic acid, except that all of the important ion species in the spectrum have mass numbers 28 units higher than the corresponding ion species in the spectrum of palmitic acid (11) for example, ion species m/z 88, 101, 157, and 284 compared to ion species m/z 60, 73, 129, and 256 (Odham and Stenhagen 1972). 

Synonyms Ethyl hexadecanoate Palmitic acid ethyl ester... 

Synonyms Ethyl hexadecanoate Palmitic acid ethyl ester Source Liang, J. H. Yeh, A. I. J. Am. Oil Chem. 

The synthesis of y-DL is the most prominent example for the microbial production of fragrance lactones. Nevertheless, the biotransformation route via P-oxidation and lactonization (Fig. 1) in yeast can be applied for the production of several lactones provided that a suitable hydroxy fatty acid as starting material is available. For example, ricinoleic acid, the starting compound for the production of y-DL, can be isolated in large quantities from castor oil. However, other hydroxy fatty acids are more difficult to obtain. For instance, researchers from Takasago International Corporation reported the conversion of 11-hydroxy palmitic acid ethyl ester to 8-decalactone by the yeast Candida sorbophila (Mitsuhashi and limori 2004). 0.13 g substrate in 30 itiL culture medium yielded 0.019 g 8-decalactone in 96 % ee optical purity after 11 days. 

Ester synthesis of fatty acid ethyl ester. The lipase-catalyzed esterification of fatty acid and alcohol is well-known. It was also favorable for the esterification of poly unsaturated fatty acids under mild conditions with the enzyme. However, the activity of native lipase is lower in polar organic solvents, i.e. ethanol and methanol. The synthesis of Ae fatty acid ethyl ester was carried out in ethanol using the palmitic acid-modified lipase. As shown in Figure 7, the reactivity of the modified lipase in this system was much higher than that of the unmoditied lipase. 

Ethyl palmitate Hexadecanoic acid ethyl ester 628-97-7... 

Dan L, Laposata M. Ethyl palmitate and ethyl oleate are the predominant fatty acid ethyl esters in the blood after ethanol ingestion and their synthesis is differentially influenced by the extracellular concentrations of their corresponding fatty acids. Alcoholism Clin Exp Res 1997 21 286-292. 

F.37) Hexadecanoic acid, ethyl ester, ethyl palmitate, ethyl hexadecanoate 698-97-7]... 

Hexadecanoic acid, ethyl ester ethyl palmitate H3C-(CH2)i4-COO-CH2-CH3 V-3... 

C12 to C20, primarily Ci6 to ( is), used as surface lubricants in the manufacture of food-contact articles. The method, which uses ethyl palmitate (Eastman Chemicals No. 1575 Red Label) as an internal standard, has been validated at 200 ppm total FAME [185]. Other FAME standards (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) are available (Applied Science Laboratories) [116], Worked out examples of additive determinations are given in the Food Additives Analytical Manual [116], which also describes a great many of indirect food additives, such as BHA, BHT, TBHQ, l-chloro-2-propanol, DLTDP, fatty acid methyl esters, w-heptyl-p-hydroxybenzoate, propyl-gallate, sodium benzoate, sodium stearoyl-2-lactylate, sorbitol and phenolic antioxidants. EPA methods 606 and 8060 describe the CGC separation of phthalate esters (direct injection) (cf. Figure 4.2). 

In another investigation, the volatile compounds were isolated [19] using a Porapack Q trap by vacuum for 2 h and were then eluted with hexane. The esters were the chemical class of compounds that predominated in the samples among 21 volatile compounds detected. Ethyl butanoate, ethyl 2-methylbutano-ate, 1-butanol, ethyl hexanoate, 3-hydroxy-2-butanone, ethyl octanoate, acetic acid, linalool, palmitic acid, and oleic acid were identified in cupuacu pulp by solid-phase extracton [15]. 

Figure D1.6.3 TLC-FID separation of a range of standard lipids. The mobile phase was 91 6 3 1 (v/v/v/v) hexane/ethyl acetate/diethyl ether/formic acid. Time refers to scanning time of the Chromarod. Abbreviations CE, cholesterol ester CHO, cholesterol DG, 1,2-diglyceride 1,3-DG, 1,3-diglyceride FFAU, highly unsaturated free fatty acid FFAS, less unsaturated free fatty acid MG, 1-monoglyceride PL, phosphatidylcholine TGU, highly unsaturated triglyceride TGS, saturated triglyceride. Tripalmitin and palmitic acid were used to complement trilinolenin and linolenic acid. Reproduced from Ackman and Heras (1997) with permission from AOCS Press.

Other acids (often as esters) have been found in fermented molasses. Usually these substances are products of bacteriological action and they are not normal constituents of unfermented molasses. Bauer" oil from the yeast fermentation of Cuban blackstrap consists chiefly of the ethyl esters of capric, lauric, myristic and palmitic acids.122 The fat from the scums of hot-room Louisiana molasses contained hexanoic (caproic) and octanoic (caprylic) acids.10 The occurrence of such volatile acids as propionic,128 butyric128 124 and valeric acids124 requires more adequate establishment. 

In recycled PP, 61 compounds were detected and 35 of them were identified. Many peaks showed very low separation levels making their identification difficult. In virgin and recycled PP the following compounds were identified Ethylbenzene and xylene were found only in the recycled resin. Present in both virgin and recycled PP were a large number of branched alkanes and n-alkanes between Qg and C25. Octadecanoic acid, methyl ester and dibutyl palmitate, which is a typical compound used in the cosmetic industry, were found only in the recycled PP. Amines such as hexamine, 3-ethyl and NIN"N" trimethyl dipropylene triamine were identified in both PP materials. Carboxylic acids and ketones were absent in both polymeric materials and so were fragrance or flavour compounds [113]. 

Sorbitan Monostearate occurs as an off white to tan colored, hard, waxy solid. It is a mixture of partial stearic and palmitic acid esters of sorbitol and its mono- and dianhydrides. It is manufactured by reacting edible commercial stearic acid (usually containing associated fatty acids, chiefly palmitic) with sorbitol. It is soluble at temperatures above its melting point in toluene, dioxane, ether, ethanol, methanol, and aniline. It is insoluble in cold water, and in mineral spirits and acetone, but is dispersible in warm water and soluble, with haze, above 50° in mineral oil and in ethyl acetate. 

It was proposed by the duPont Co(Ref 3) to prepare flashless smokeless proplnts from NC DNT, in which is incorporated ethyl palmitate or other esters of organic acids insol in water but forming a gelatinous mass with NC DNT at about 80°... 

The sodium or potassium salt of palmitic acid, or of stearic acid or the mixed salts of several acids obtained from ordinary fats, is the common substance known as soap. This particular reaction of hydrolysis, is, therefore, known, also, as a reaction of saponification (soap formation). Strictly speaking the reaction of saponification applies only to the alkaline hydrolysis of fats, i,e., of glycerol esters, but, as the hydrolysis of other esters is a reaction of exactly the same character, the term is used to apply equally to the hydrolysis of any ester in presence of an alkali. In the case of the lower alcohol and lower acid esters, e.g., ethyl acetate, the salt formed is not a soap but is a crystalline salt, sodium acetate. 

Ascorbic acid was used to prevent the oxidation of olive oil, milk, arachis nut oil, lard, ethyl ester of lard, cottonseed oil, pork, and beef fat (4) data showing activity alone and as a synergist are reviewed. Ascorbyl laurate, myristate, palmitate, and stearate were similarly active, although only AP is listed as a preservative in GFR. Ascorbic acid synergy with tocopherol was also reviewed. 

A very different type of reaction is represented by the conjugation of xenobiotic alcohols with fatty acids, yielding highly lipophilic metabolites accumulating in tissues. Thus, ethanol and haloethanols form esters with palmitic acid, oleic acid, linoleic acid, and lin-olenic acid enzymes catalyzing such reactions are cholesteryl ester synthase (EC 3.1.1.13) and fatty-acyl-ethyl-ester synthase (EC 3.1.1.67) (71). Larger xenobiotics such as tet-rahydrocannabinols and codeine are also acy-... 

A membrane cell recycle reactor with continuous ethanol extraction by dibutyl phthalate increased the productivity fourfold with increased conversion of glucose from 45 to 91%.249 The ethanol was then removed from the dibutyl phthalate with water. It would be better to do this second step with a membrane. In another process, microencapsulated yeast converted glucose to ethanol, which was removed by an oleic acid phase containing a lipase that formed ethyl oleate.250 This could be used as biodiesel fuel. Continuous ultrafiltration has been used to separate the propionic acid produced from glycerol by a Propionibacterium.251 Whey proteins have been hydrolyzed enzymatically and continuously in an ultrafiltration reactor, with improved yields, productivity, and elimination of peptide coproducts.252 Continuous hydrolysis of a starch slurry has been carried out with a-amylase immobilized in a hollow fiber reactor.253 Oils have been hydrolyzed by a lipase immobilized on an aromatic polyamide ultrafiltration membrane with continuous separation of one product through the membrane to shift the equilibrium toward the desired products.254 Such a process could supplant the current energy-intensive industrial one that takes 3-24 h at 150-260X. Lipases have also been used to prepare esters. A lipase-surfactant complex in hexane was used to prepare a wax ester found in whale oil, by the esterification of 1 hexadecanol with palmitic acid in a membrane reactor.255 After 1 h, the yield was 96%. The current industrial process runs at 250°C for up to 20 h. 

Cetyl esters wax. See Cetyl esters Cetyl 2-ethylhexanoate. See Cetyl octanoate Cetyl ethyl morpholinium ethosulfate N-Cetyl ethylmorpholinium ethosulfate N-Cetyl-N-ethyl morpholinium ethyl sulfate. SeeCetethyl morpholinium ethosulfate Cetylic acid. See Palmitic acid... 

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