364 DIGESTION AND RESORPTION OF FATS 



acid, there were so many and such interfering procedures 

 (prolonged boiling with acids and alkalies, treatment with 

 hydrazine hydrate, sodium nitrite, etc.) required that it 

 seemed quite impossible that any substance active in small 

 amounts could remain intact and maintain itself in practi- 

 cally unchanged quantity through all these processes. 

 . . . The augmenting influence of the bile upon fat cleav- 

 age by the pancreatic juice depends upon its containing 

 biliary salts of alkalies. The economy in this respect works 

 with precisely the same means as the technical chemist, who 

 splits fats today with ferments and activates the latter by 

 small quantities of manganese sulphate." 



Question of the Complex Nature of the Pancreatic 

 Steapsin. Here arises the further question of just how this 

 powerful effect (for the fat splitting action of the pancreatic 

 steapsin can be increased more than tenfold at times by the 

 addition of small amounts of bile) is to be interpreted. The 

 author's pupil, Hedwig Donath, whom he induced to take up 

 this question seriously, answers it by supposing that we are 

 here dealing with the conversion of an inactive zymogen or 

 preferment into an efficient enzyme, a slow transformation 

 being also possible ' ' spontaneously, ' ' but greatly accelerated 

 by the catalytic action of the bile salts. From this it is 

 apparently easy to appreciate why steapsin preparations 

 may spontaneously undergo changes of such a character that 

 add to their direct effectiveness but diminish their capacity 

 for activation by cholic acid. Activation of the pancreatic 

 ferment by cholates results in increasing the ferment activity 

 only within certain limits in proportion to the quantity of 

 cholic acid employed ; from this limit forward further addi- 

 tion of cholic acid is not followed by any increase in 

 efficiency. 39 This discovery is of general interest from the 

 fact that in many ways it suggests certain analogies which 



* H. Donath, Hofmeister's Beitr., 10, 390, 1907, conducted under direction 

 of O. v. Ftirth ; cf . also O. Rosenheim, Jour, of Physiol., 40, Proc. Physiol. Soc., 

 1910 Separation of the Pancreatic Lipase from Its Coenzyme. 



