ALCOHOLIC FERMENTATION OF SUGAR 345 



publications on the subject which the writer gladly forbears 

 to inflict. It may be sufficient to refer here to one of these 

 only, 43 that of Wohl: 44 



Methylglyoxal Lactic Acid Alcohol 



COH COH COH COH COOH CO 2 

 CH.OH C.OH CO CO 

 CH.OH CH CH 2 CH, 



> > > Glycerine Aldehyde 3 



CH.OH CH.OH CH.OH COH 

 CH.OH CH.OH CH.OH CH.OH 

 CH 2 OH CH 2 .OH CH 2 OH CH 2 .OH 



Mention may also be made here of pyroracemic acid 

 (CHg.CO.COOH), which, according to Paul Meyer, 45 may 

 be placed among the sugar-formers, and which, according 

 to Neuberg, 46 can be fermented by yeast to aldehyde and 

 carbonic acid (CH 3 .CO.COOH == CH 3 .COH + C0 2 ), as open 

 to consideration as a possible intermediate stage of physi- 

 ological sugar catabolism. 



Mechanism of Alcoholic Fermentation of Sugar. It was 

 originally thought that by thorough study of alcoholic fer- 

 mentation of sugar we might attain definite information as 

 to the catabolism of sugar in the animal economy. The fact, 

 already stated, that we have no sound support for the as- 

 sumption that alcohol formation is of any physiological 

 importance in the animal body, makes the value of studies in 

 this line of questionable worth. Then, too, it is obvious that 

 it is impossible, in what must be merely a brief sketch of the 

 subject of fermentation, to properly deal with a branch 

 which in the last few decades has grown into an independent 

 science. The only thing which can be appropriately done 

 here is to briefly indicate the intermediate stages, as we- 



43 A. Wohl (Danzig), Biochem. Zeitschr., 5, 54, 1907. 



44 Without reference to the stereochemical configuration. 



45 P. Mayer (C. Neuberg's Lab.), Biochem. Zeitschr., 40, 441, 1912. 

 46 C. Neuberg, Berlin, physiol. Ges., Nov. 1, 1912. 



