Palmitic acid, absorption

Fig. (15) Effects of chondroitin sulfate on palmitic acid absorption by brush border membrane vesicles. The rate of absorption is expressed as the percentage of the activity in the absence of chondroitin sulfate. Results are expressed as means + s.e.m. of four experiments. p<0.01, significantly different from control.

B14. Blomstrand, R., A study on the intestinal absorption of fat in normal adults and in non-tropieal sprue with carbon-labelled oleic acid and palmitic acid. Acta Med. Scand. 152, 129-138 (1955). 

M. Hashizume, T. Douen, M. Murakami, A. Yamamoto, K. Takada, S. Muranishi, Improvement of Large Intestinal Absorption of Insulin by Chemical Modification with Palmitic Acid in Rats , J. Pharm. Pharmacol. 1992, 44, 555-559. 

Hashizume, M., Douen, T., Murakami, M., et al. Improvement of large intestinal absorption of insulin by chemical modification with palmitic acid in rats. J. Pharm. Pharmacol. 44 555-559, 1992. 

Figure 6.3 Effects of hydrocarbon chain modifications on melting points of similar-sized cuticular lipids. When lipids melt, the absorption frequency of C-H symmetric stretching vibrations increases from -2849 cm1 to -2854 cm4. From right to left, compounds are (chemical change relative to n-alkane, molecular mass in daltons) filled circles, n-dotnacontane (no change, 450) open circles, palmitic acid myristyl ester (wax ester, 452) filled triangles, 13-methylhentriacontane (methyl-branched alkane, 450) open triangles, (Z)-13-tritriacontene (double bond, 462) filled squares, 9,13-dimethylhentriacontane (2 methyl branches, 464) open squares, oleic acid oleyl ester (2 double bonds and an ester link, 532). Data from Gibbs and Pomonis (1995) and Patel el al. (2001).

Betapol , a human milkfat substitute produced by Loders Croklaan (Wormerveer, the Netherlands), is produced by interesterification of vegetable oils in which the component TAGs have been modified to more closely resemble those found in breast milk. This product closely mimics the specific structure and fatty acid composition of human milkfat and resembles breast milk in terms of its nutritional value and high content of palmitic acid at the sn-2 position than other milkfat substitutes. In addition, the use of Betapol in infant formula can lead to improved mineral and fat absorption and less calcium soap formation within the intestinal lumen resulting in softer stools. 

Fatty acids increase intestinal absorption via their influence on the paracellular and transcellular transport route. Most interesting results were obtained with lauric acid, palmitic acid, capylic acid, and oleic acid or their salts. Cytotoxic effects of fatty acids are concentration dependent long-chain unsaturated fatty acids especially can cause epithelial cell damage. ° ... 

Chloramphenicol Palmitate, USP. Chloramphenicol palmitate is the palmitic acid ester of ehloramphenieol. It is a tasteless prodrug of chloramphenicol intended for pcdiatric usc. The ester must hydrolyze in vivo following oral absorption to provide the active form. Erratic scrum levels were asstK iated with early formulations of the palmitatc. but the manufacturer claims that the bioavailability of the current preparation is comparable to that of ehloramphenieol itself. 

In 1955 Blomstrand [93] fed phospholipids labeled with [ " C]palmitic acid to rats with both the bile and thoracic duct cannulated. The results indicated that in this situation 68% of the fatty acids were absorbed and that bile was not obligatory for absorption of phospholipid fatty acid. The distribution of the labeled fatty acid in the thoracic duct lipids showed the same pattern as after feeding the free fatty acid, indicating that the phospholipids had been hydrolyzed before absorption. The mechanism responsible for the hydrolysis of phospholipid in bile fistula rats is not obvious. A novel enzyme with phospholipase Aj activity has been demonstrated in the rat intestine [94]. This enzyme has its highest specificity for phosphatidyl glycerol and its role for the hydrolysis of dietary PC is unclear. 

Very few determinations have been made of the total fatty acid content of marine waters. Of the few methods available, a technique which is reported to be reliable is that of extraction of the free acids with chloroform at pH 2 followed by formation of a copper complex and final estimation of the complexed copper by atomic absorption spectrophotometry (Treguer et al., 1972). The free fatty acid contents are reported as palmitic acid equivalents. The method, however, has not yet been widely adopted for routine use. 

Mesiha, M.S., Ponnapula, S., Plakogiannis, F. Oral absorption of insulin encapsulated in artificial chyles of bile salts, palmitic acid and a-tocopherol dispersions. Int. J. Pharm., 249,1, 2002. 

Unfortunately, sueh formulas have resulted in poor absorption of fats and minerals, particularly when studied in infants dining the first few weeks of life [62, 91, 92]. This is because PA is present in the sn-1 position (human breast milk, lard native, enzyme-direeted and randomly ehemieally interesterified fats plant) eompared with the sn- and sn-3 positions (bovine milk, randomly ehemieally interesterified lard or crude palm oil). It was found the relative absorption of palmitic acid and full fat was linearly related to the proportion of palmitic acid in the sn-1 position of the TAG in human infants. Panereatie lipase selectively hydrolyses the fatty aeids at the sn- and sn-3 positions, yielding free fatty acids and monoacylglycerols (MGs). The TAG sn-1 position is absorbed more effieiently than free palmitic acid and it is conserved through the digestion, absorption and ehylomicron TAG synthesis [63, 91]. 

Clinical studies in term (Camielli et al. 1996, Kennedy et al. 1999, Lopez-Lopez et al. 2001) and preterm infants (Camielli et al. 1995, Lucas et al. 1997) have demonstrated the correlation between the level of palmitic in the sn2 position on fatty acids and calcium absorption. The reduction in calcium and fatty acid absorption is accompanied by increased calcium soaps and, consequently, hard stools (Quinlan et al. 1995). Infants receiving the high sn2 formula had softer stools and fewer formed and hard stools than did control regular vegetable oil formula group (Sidnell and Greenstreet 2011, Kennedy et al. 1999, Litmanovitz et al. 2014, and Yao et al. 2014). 

One of the interesting features of fatty acid is the permeation enhancement. Palin et al. (1986) studied the absorption enhancement of various fatty acids on cefoxitin absorption in rat intestinal loops in situ. They ranked the fatty acids enhancement property as lauric acid > palmitic acid > caprylic acid > oleic acid. But in the study of in situ colonic cefmetazole absorption in rat and of... 

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