INTERRELATION OF ACETONE BODIES 447 



further synthetic changes. A number of authorities, as 

 Minkowski and von Noorden, have thought that it may per- 

 haps be looked upon as an intermediate link between fat and 

 sugar. 39 The statement has been made above that there 

 is at present no convincing basis for Geelmuyden's view that 

 the acetone bodies should be regarded as transition stages in 

 the supposed formation of sugar from fat. There are many 

 arguments against the idea that oxybutyric acid can be in 

 any way concerned with the synthetic formation of fatty 

 acids from carbohydrates. Embden, in his last publications, 

 expresses the belief that the route from sugar to the fatty 

 acids may, perhaps, lie through lactic acid, acetaldehyde and 

 diacetic acid. ' 'Acetaldehyde, as E. Friedmann first showed, 

 in the experimentally perfused liver forms diacetic acid. If 

 acetaldehyde, as would appear, is a product of carbohydrate 

 catabolism which develops in very large amounts, we may 

 perhaps regard this substance, as earlier authors have sug- 

 gested, as the point of attack in the synthetic production of 

 fatty acids from carbohydrates." 40 Should this line of 

 thought prove correct an interesting relation would be estab- 

 lished between the acetone bodies with both the anabolism 

 and catabolism of the higher fatty acids. Thus far, how- 

 ever, the connection of these substances with fat decomposi- 

 tion in the economy constitutes the best based phase of the 

 whole problem. 



The fact that enzymic catalysers are known to exist in 

 the tissues, which are capable of oxidizing oxybutyric acid 

 to form diacetic acid, 41 and of converting the latter into 

 acetone by splitting off carbon dioxide, 42 is no proof that this 

 is a process which takes place physiologically. 



It is impossible to say at present what factors determine 



39 Cf . B. 0. Przibram, 1. c. 



40 G. Embden and M. Oppenheimer, Biochem. Zeitschr., 45, 202-203, 1912. 



41 A. F. Wakeman and H. D. Dakin, Jour, of Biol. Chem., 6, 373, 1909. 



42 L. Pollak (R. Paltauf's Instit., Vienna), Hofmeister's Beitr. 10, 232, 

 1907. 



