344 SUGAR DESTRUCTION IN THE ECONOMY 



line of thought in endeavoring, by studying the electrolysis 

 of different sugars, to bring out analogies to the physio- 

 logical destruction of sugar in the living body. Apparently 

 formalydehyde and pentose may appear as stages of sugar 

 cleavage and of sugar synthesis, both in the electrolytic 

 reduction of grape-sugar and in the action of oxygen on 

 glucose. We are probably here dealing with a change of 

 equilibrium : 



GLUCOSE PENTOSE FORMALDEHYDE 



C 6 H 12 6 ^ZZZf:C 6 H 1 o0 6 + CH 2 0. 



W. Lob, who was able to detect in the electrolysis of 

 grape-sugar in dilute sulphuric acid (using lead electrodes) 

 gluconic acid, saccharic acid, arabinose, arabonic acid, tri- 

 oxyglutaric acid, formaldehyde and formic acid, 41 suggests 

 the following schematic plan for the process : 



GLUCOSE - > ARABINOSE -|- FORMALDEHYDE 



C 6 H ia O 6 CH 2 O 



CH,.OH COOH CH 2 .OH COOH H CO a 

 (CH.OH) 4 (CH.OH) 4 (CH.OH), (CH.OH) 3 COOH CO 

 COOH COOH COOH COOH 



Gluconic Acid Saccharic Acid Arabonic Acid Trioxyglutaric Acid Formic Acid. 



The influence of ultraviolet light rays is also followed by 

 cleavage of sugar with formation of aldehydes and volatile 

 acids, and if continued may lead to the appearance of 

 formaldehyde and carbonic acid. 42 



Speaking in general terms it can be readily recognized 

 that we have not progressed in the study of the catabolism 

 of sugar in the economy much beyond the stage of 

 hypothesis. As it is well known that everything that is 

 printed is not for that reason true, there are a great many 



" Concerning formic acid as an intermediate product in sugar cleavage in 

 the body, cf. O. Steppuhn, and H. S'chellenbach, Zeitschr. f. physiol. Chem., 

 80, 274, 1912. 



48 P. Meyer (Neuberg's Lab.), Biochem. Zeitschr., 32, I, 1911; A. Jolles, 

 ibid., S3, 252, 1911; H. Bierry, V. Henri and Ranc, Compt. rend., 152, 1629, 

 1911, and earlier contributions. 



