DISINTEGRATION OF FATTY ACID CHAINS 435 



by any means. It is stated that in severe diabetes some- 

 times there are excreted a greater number of molecules of 

 oxybutyric acid than can be accounted for by the number of 

 molecules of fatty acids which are in course of decomposi- 

 tion. As; a matter of fact it is very difficult, if at all possible, 

 to estimate correctly the number of the latter in our calcula- 

 tions in metabolic experiments. However, were this the 

 case it would strongly indicate that the long fatty acid chains 

 are not reduced step by step until they come to the four 

 carbon atom stage and are changed into butyric acid; we 

 would have to assume that the chain is first broken into a 

 number of segments, each of which is transformed into 

 butyric acid. 8 Ernst Friedmann 9 found in F. Hofmeister's 

 laboratory that (of a number of substances with two-armed 

 carbon chain subjected to investigation) acetaldehyde alone 

 was synthesized into diacetic acid in perfusion of the liver. 

 As two molecules of acetaldehyde are very readily condensed 

 into aldol and this in perfusion experiments is capable of 

 transformation into diacetic acid, it is not unlikely (follow- 

 ing the conceptions of Magnus-Levy 10 and Spiro) that the 

 reactions may be represented by the following formulae : 



ACETALDEHYDE ALDOL 



CH,.COH + CH 3 .COH = CH 8 .CH(OH).CH 2 .COH 



ALDOL /3-OXYBUTYRIC ACID 



CH,.CH(OH).CH 2 COH + O = CH 3 .CH.OH.CH 2 .COOH. 



It might also be imagined that the fatty acid chains are 

 primarily broken up into links with only two carbon atoms 

 each, and that these then become synthesized by way of 

 acetaldehyde into ^-oxybutyric acid. 



8 A. Magnus-Levy, Arch. f. exper. Pathol., 45, 433, 1901. 



*E. Friedmann (F. Hofmeister's Lab., Strassburg), Hofmeister's Beitr., 

 11, 202, 1908. 



10 A. Magnus-Levy, Die Oxybutyrsaure und ihre Beziehungen zum Coma 

 diabeticum, Leipzig, F. C. W. Vogel, 1899, p. 78. 



