336 SUGAR DESTRUCTION IN THE ECONOMY 



influences of muscle plasma and pancreatic extract, can be 

 restored by boiling with weak hydrochloric acid. Levene 

 also succeeded in recovering from such a solution the 

 osazone of a disaccharide. 20 



What now, in conclusion, is the exact meaning of this 

 long disquisition ? No one doubts in the least that glycolysis 

 takes place in the tissues and that the living tissues are able 

 to catabolize sugar. The point in question is, however, 

 whether we are in position to reproduce the process with 

 dead fragments of tissue and tissue extracts, whether in such 

 case we are justified in referring the glycolysis to the influ- 

 ence of ferments which can operate independently of the liv- 

 ing cells. As far as the writer sees, the question cannot at 

 present be either affirmed or denied with certainty; and it 

 seems not improbable that under proper conditions ferments 

 can be obtained from tissues which in some way chemically 

 change the sugar, either to induce cleavage or synthesis. 

 But that is probably all that can be said. For the assump- 

 tion that this chemical cleavage is to be regarded as 

 analogous to the vital combustion of sugar, not to say 

 equivalent, there is in the writer's opinion not the least 

 basis. And, too, it certainly has not been shown that the 

 activity of Cohnheim's pancreatic activator has anything 

 to do with the puzzling influence which the living pancreas 

 exercises upon the metabolism of sugar. If Hall (vide sup.) 

 found that alcoholic extract of pancreas is more efficient 

 than the pancreas itself, and if Levene found the pancreas 

 inactive in many cases, but did find an extract of spleen 

 to be active, it must seem that an unprejudiced person 

 would conclude that they are perhaps dealing with a non- 

 specific effect. In the course of the last few years we have 

 heard so much about the activating influences of lipoids, and 

 especially tissue lipoids, upon the processes of fermentation 

 and intoxication of the most varied types, that one may well 



80 P. A. Levene and G. M. Meyer, Jour, of Biol. Chem., 9, 97, 1911 ; 11, 347, 

 353, 1912. 



