on the Proteolytic Action of the Pancreatic Ferment. 119 
~~ Ra 
causing destruction of the ferment, as after dialysis the ferment was 
-again active. 
Our results accord in the main with Heidenhain’s; acceleration, 
_ followed by retardation of proteolytic action as seen from the follow- 
ing figures. 
Undigested Fibrin Relative proteo- 
NaCl. residue. digested. lytic action. 
0 0°2993 gram. 70°07 per cent. 100°0 
0-05 per cent. 0°2635 73°65 1051 
0°2 0°3001 69°99 99°8 
0°5 0°3372 66°28 94°5 
10 j 0°3923 60°77 86°7 
2°0 074352 56°48 80°6 
3°0 0°436] 56°39 80°4 
5°0 04740 52°60 75°0 
Potassium bromide and potassium iodide. 
The action of these two salts is wholly an accelerating one; more 
pronounced, however, in the case of the bromide than in the iodide. 
Following are the results of the experiments : 
Undigested Fibrin Relative proteo- 
KBr. residue. digested. lytic action. 
0 0°3881 gram. 61°19 per cent. 100:0 
0°05 per cent. 0°3773 62°20 101°6 
05 0°3681 63°19 103°2 
20 0°3795 62:05 101-4 
5-0 0°3278 67°22 109°8 
KI. 
0 0°3881 gram. 61°19 per cent. 100°0 
0°05 per cent. 0°3575 64°25 105°0 
0°5 0°3915 60°85 99:4 
: 3°0 0°3897 61:03 99°7 
Influence of gases on the proteolytic action of trypsin. 
Podolinski* in Heidenhain’s laboratory, has shown that oxygen 
"gas has the power of converting the zymogen of pancreas. into the 
active ferment and that carbonic acid is without such power; more- 
over, that carbonic acid added to a sodium carbonate solution of 
-pancreatin (trypsin) retards the proteolytic action of the ferment, 
because the normal carbonate is thus changed into acid carbon- 
ate which does not favor the action of the ferment so well as the 
simple salt. Hydrogen was found to be without such action. Podo- 
linski further found that while oxygen favored the conversion of 
_ zymogen into the ferment, it did not influence the proteolytic action 
* Pfliiger’s Archiv, vol, xiii, p. 426. 
