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Return to Abstracts of Literature 1500-1749

Literature Abstracts

 1717.    APPEL, H., BÖHM, H., KEIL, W., AND SCHILLER, G.  [Fats From Fatty Acids With Odd Numbers of Carbon.  VII.  Preliminary Communication Concerning Properties, Stability, Physiology, and Toxicology of Synthetic Fats From Paraffin Fat Acids.]  Ztschr. Physiol. Chem., vol. 282, 1947, pp. 220-244; Chem. Abs., vol. 43, 1949, p. 9487.

        Synthetic fats prepared from glycerol and fat acids obtained by oxidation of paraffin from various sources are more resistant to oxidation and become rancid more slowly than natural fats.  Of the fat acids not occurring in natural fats odd-numbered ones, approximately 48% in the synthetic fat, are metabolized by animals and man like natural fat.  After feeding odd-numbered saturated acids with C11-C19, 9-10 unsaturated acids are found in depot fat.  Branched-chain acids, approximately 15% of the synthetic fat and removable by recrystallization of the paraffin or the fat acids, when fed are mostly excreted in the urine as low-molecular branched acids, dicarboxylic acids, and unidentified acid products.  Only a very small amount appears in depot fat.  A diet high in branched-chain fats inhibits growth in rats and is toxic.  Dicarboxylic acids from C9-C16, 3-4% of the synthetic fat and removable with alkali or by absorption, are excreted in the urine as degraded dicarboxylic acids from C6-C10.  Unsaturated acids with double bonds mainly in 2-3 and 4-5 positions and with transconfiguration are present only in very small amounts.  The unsaponified fraction consisting of paraffin, alcohols, and ketones is nontoxic in the low concentration, less than 1%, present in synthetic fat.

       KEILIG, F.  See abs. 2932, 2934.