460 LACTIC ACID 



Emb den's Schema of Sugar Catabolism in the Living 

 Body. Thanks to a long series of remarkable studies carried 

 on by Gustav Embden 20 in the Frankfurt Institute of 

 Physiological Chemistry in collaboration with a number of 

 associates, we are able today to frame very exact ideas as 

 to the decomposition of sugar into lactic acid and the further 

 catabolism of the latter. Embden 21 condenses these points 

 in the following schema : 



a-Glucose 



it 



Glycerol-aldehyde 7""** Glycerol 



It 



i-Lactic Acid 



It 



Racemic Acid < > 5-Alanin 



I 



Diacetic Acid < Acetaldehyde < > Ethyl Alcohol 



I 



Acetic Acid. 



If we consider this schema somewhat more fully, in ac- 

 cordance with it we may suppose that physiologically sugar 

 catabolism would follow the course below indicated : 



GLYCEROL- LACTIC RACEMIC ACETIC 



8UGAB ALDEHYDE ACID ACID ACETALDEHYDE 



CH, CH, 



COH " COOH. 

 COH COOH COOH 

 CH.OH 



COH 



Glycerol-aldehyde as an Intermediate Product Between 

 Sugar and Lactic Acid. The assumption that glycerol- 

 aldehyde is an intermediate product between glucose and 



30 G. Embden and associates, Biochem. Zeitschr., 45, 1-206, 1912, and their 

 earlier studies; cf. therein Literature. 



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



