Linoleic acid, formula

As mentioned earlier, both MCTs and LCTs are used in tube feeding products. Corn, soy, and safflower oils have been the mainstay sources of fat in these products, providing mainly co-6 polyunsaturated fatty acids (PUFAs). On the other hand, some newer EN products contain higher quantities of co-3 PUFAs from sources such as fish oil [i.e., docosahexenoic acid (DHA) and eicosapentenoic acid or (EPA)]. Still other formulas contain higher quantities of monounsaturated fatty acids from canola oil and high-oleic safflower or sunflower oils. The essential fatty acid (EFA) content (mainly linoleic acid) of EN... 

BASIC PROTOCOL I PREPARATION OF FATTY ACID METHYL ESTERS FROM LIPID SAMPLES CATALYZED WITH BORON TRIFLUORIDE IN METHANOL In this method, lipid samples are first saponified with an excess of NaOH in methanol. Liberated fatty acids are then methylated in the presence of BF3 in methanol. The resulting fatty acid methyl esters (FAMEs) are extracted with an organic solvent (isooctane or hexane), and then sealed in GC sample vials for analysis. Because of the acidic condition and high temperature (100°C) used in the process, isomerization will occur to those fatty acids containing conjugated dienes, such as in dairy and ruminant meat products, that contain conjugated linoleic acids (CLA). If CLA isomers are of interest in the analysis, Basic Protocol 2 or the Alternate Protocol should be used instead. Based on experience, this method underestimates the amount of the naturally occurring cis-9, trans-11 CLA isomer by -10%. The formulas for the chemical reactions involved in this protocol are outlined in Equation D1.2.1 Saponification RCOO-R + NaOH, RCOO-Na + R -OH v 100°C DC Esterification RCOO-Na + CH,OH r 3 v RCOO-CH, + NaOH ioo°c ... 

In humans, the conversion of ALA to EPA and DHA is extremely slow, with only about 15% and 5% of ALA converted to EPA and DHA, respectively (Cunnane, 1995). This conversion appears to be affected by a number of dietary factors. For example, a diet rich in linoleic acid has been found to reduce this conversion by as much as 40% (Emken, 1995). In addition, saturated and lruns fatty acids also interfere with ALA desaturation and elongation steps (Ackman and Cunnane, 1992 HouwelingenandHornstra, 1994). DHA can be reconverted back to EPA, although in humans it appears to be a very minor pathway (Brossard et al., 1996). DHA appears to play an important in the brain and retina and was found to be incorporated during the last trimester of pregnancy and the first year of life. Visual acuity was shown to develop much faster in preterm infants fed formulas rich in DHA compared with standard infant formulas low in long chain n-3 fatty acids (Jorgensen et al., 1996). 

The answer is d. (Murray, pp 258-297. Scriver, pp 2705-2716. Sack, pp 121-138. Wilson, pp 362-367.) Infants placed on chronic low-fat formula diets olten develop skin problems, impaired lipid transport, and eventually poor growth. This can be overcome by including linoleic acid to make up 1 to 2% ol the total caloric requirement. Essential fatty acids are required because humans have only A", A , A , and A fatty acid desaturase. Only plants have desaturase greater than A . Consequently, certain fatty acids such as arachidonic acid cannot be made from scratch (de novo) in humans and other mammals. However, linoleic acid, which plants make, can be converted to arachidonic. acid. Arachidonate and eicosapentaenoate are 20-carbon prostanoic acids that are the starting point of the synthesis of prostaglandins, thromboxanes, and leukotrienes. 

Hrboticky N, Mackinnon MJ, Innis SM. Effect of a vegetable oil formula rich in linoleic-acid on tissue fatty-acid accretion in the brain, liver, plasma, and erythrocytes of infant piglets. Am J Clin Nutr 1990 51(2) 173-182. 

This first generation n-3 deficiency may be considered a model of the human case in which the mother has a diet containing a-linolenic acid but low in long-chain n-3 polyunsaturates such as DHA. The infant is then given a formula with its EFA content derived from corn oil or some other linoleic acid-rich seed oil and devoid of any long-chain n-3 pol3ninsat-urate source, as has been a common p ractice in North America... 

Adam, O., Wolfram, G., and Zollner, N. (1982) Prostaglandin Formation in Man During Intake of Different Amounts of Linoleic Acid in Formula Diets, Ann. Nutr. Metab. 26,315-323. 

Classification Fatty acid alkanolamide Definition Mixt. of ethanolamides of linoleic acid Empirical C22H41NO3 Formula ... 

Definition Salt of linoleamidopropyl dimethylamine and a dimer of linoleic acid Empirical C82H152N4O6 Formula (CisH3202)2 C23H44N2O Uses Antistat in cosmetics, creams, lotions, shaving creams, soaps hair conditioner/softener/lubricant Trade Name Synonyms Lanaetex LO-80 [Lanaetex Prods.] Necon LO-80 [AIzo... 

CAS 17673-59-3 EINECS/ELINCS 241-655-4 Synonyms Linoleic acid, oleyl ester 9,12-Octadecadienoic acid, 9-octadecenyl ester 9-Octadecenyl 9,12-octadecadienoate Oleyl (9Z, 12Z)-octadeca-9,12-dienoate Definition Ester of oleyl alcohol and linoleic acid Empirical C36H66O2 Formula ... 

Write structural formulas for glycerol, stearic acid, palmitic acid, oleic acid, and linoleic acid. 

More than 500 different fatty acids have been isolated from various cells and tissues. Given in Table 19.1 are common names and structural formulas for the most abundant of them. The number of carbons in a fatty acid and the number of carbon-carbon double bonds in its hydrocarbon chain are shown by two numbers separated by a colon. In this notation, linoleic acid, for example, is designated as an 18 2 fatty acid its 18-carbon chain contains two carbon-carbon double bonds. 

Draw the structural formula of a lecithin containing one molecule each of palmitic acid and linoleic acid. 

Hansen and his co-workers undertook a long term massive study of essential fatty acid phenomena in infants. In a clinical study of 428 infants, who were fed with five different dietary formulae, they found differences in the dienes, trienes, tetraenes, pentaenes and hexaenes measured by alkaline isomerization. They also found that the content of linoleic acid in the proprietary formulae varied... 

Infants raised on cow s milk may obtain as little as 1% of their calories from linoleic acid, whereas commercial infant formulas presently in common use normally contain vegetable oils and may provide more than 20% of total calories as linoleic acid (Schubert, 1973). Human milk, which is accepted as the optimal nutritional standard in infancy (Macy Kelly, 1961 Jelliffe Jelliffe, 1971) normally provides about 4% of total calories as linoleic acid (Schubert, 1973), but the percentage of linoleic acid in human milk may vary anywhere from 1% to more than 15% (Cuthbertson, 1976). Although various S3rmptoms attributed to dietary deficiencies of essential fatty acids have been observed by a number of investigators, they occur only rarely, and Cuthbertson (1976) considers that the minimum requirement for children is, in fact, less than 0.5% of calories. 

There are two possibilities for P-scission of each hydroperoxide fatty acid (Fig. 3.26). Option B , i. e. the cleavage of the C-C bond located further away from the double bond position, is the energetically preferred one since it leads to resonance-stabilized oxoene or oxo-diene compounds. Applying this P-scission mechanism ( B ) to both major monohydroperoxide isomers of linoleic acid gives the products shown in Formula 3.72 and 3.73. 

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