646 



CATALASE ACTION 



20 gm. of plant in 200 cc. of 

 water. 



138 

 276 

 414 



552 



K^ X 10^ 



40 

 33 

 31 

 26 



X? X lO' 



38 

 35 

 33 

 29 



A' + 10* 



43 

 38 

 35 

 31 



However, this assumption does not hold, as the above table shows. 



Here the dilution is eight times greater than in the former case. The 



dx 

 formula — = K{a — xY does not apply here. It is obvious that the 

 dt 



dilution is the factor which combines its injurious effects with the 

 chemical influences. Herzog remarks that inactivation of enzymes 

 is the quickest in dilute solutions according to the principle of Willard 

 Gibbs. It is known in breweries that the diastase is resistant in 

 concentrated malts, but is quickly destroyed in dilute malt. 



Conclusions as to Catalase. — Ulva tmiiata Setchell and Gardner 

 contains a catalase which adheres to the cells to a certain extent, 

 but may, mechanically or by exosmosis, pass into the surrounding 

 medium. This catalase is able to act in a neutral medium on peroxide, 

 the reaction being monomolecular. In an alkaline medium the 

 catalase decomposes peroxide following the formula of Schmidt- 

 Nielsen 



■\/ff — "S/ a — X 



K 



t V a (a — x) 



The reaction time varies in a linear relation with the concentration 

 of the peroxide. Reaction velocity and enzyme concentration vary 

 in a linear relation. Reaction velocity and peroxide concentration 

 vary in a continuous non-linear and non-exponential relation. Since 

 the peroxide is in excess of the feeble catalase, these facts are in agree- 

 ment with the data of Senter on blood catalase. On dilution the 

 enzyme is destroyed, following highly exponential lines 



dx 



— = K (a- x)^ 



at 



or even 



dx 



dt 



= K {a- x)* 



