642 



CATALASE ACTION 



doubt that this relation will exist also with different enzyme quantities. 

 Reaction time is a very valuable index for enzyme determination, and 

 the fact that Duclaux and Went are the only authors who used this 

 index in physiology shows us that it is very little known. The 

 catalase strength is often determined by measuring a pressure after 

 a certain time, but this method has no value for quantitative 

 determinations. 



3 2 1 CO. 



Amount of peroxide 



Fig. 3. Relations of peroxide quantity, reaction time, and reaction velocity. 



Influence of External Conditions. — Under certain precautions the 

 reaction follows the monomolecular line. For example, 3 gm. of 

 Ulva were ground as fine as possible in a mortar with 15 cc. of distilled 

 water. After reaction with 4 cc. of peroxide and 0.4 cc. of 0.1 n 

 NaaCOs solution we calculated the resulting curve. 



