2*o BOTANICAL GAZETTE [march 



The depressing effect of chlorides on oxidase activity is in 

 contrast with their action on other enzymatic processes. Thus 



Nasse (25), Kubel (22), Cole (10), Wohlgemuth (31), Lisbonne 



(23), Hawkins (18), and others have found that chlorides increase 

 the diastatic power of various preparations of diastase. Nasse, 

 however, found that under certain conditions sodium chloride 

 retarded diastatic activity, and later Hawkins showed that sodium 

 chloride and potassium chloride in certain dilute concentrations 

 (M/128-M/512) retard diastatic activity. It would have been 

 better if the effect of the chlorides upon oxidase activity had been 

 determined in a greater number of concentrations, and it will be well 

 in the future to do so in studying this problem. The effect of salts 

 upon lipase activity is also of interest in this connection. Loeven- 

 hart and Peirce (24), Gerber (14), Terroine (30), Hamsik (16), 

 Falk (12), and others found that the chlorides of various alkalies 

 and alkaline earths retard lipase activity. Terroine found that 

 the concentration of the salts which he studied determined the 

 nature of their influence. Buchner, Buchner, and Hahn (7) 

 found that the chlorides of sodium, calcium, barium, and am- 

 monium inhibit the fermentation of cane sugar or glucose in the 

 presence of pressed yeast. * 



The results presented in table VI do not show any marked differ- 

 ence in the behavior of the different chlorides tested. The cations, 

 judging from the limited data available, apparently have little 

 or no effect; or at least their chlorides all behave very much 

 in the same manner. In this respect the alkali salts are different 

 in their effect upon the fire-holding capacity of tobacco, for here 

 the salts of caesium, rubidium, and potassium in general are much 

 more favorable to combustion than the corresponding salts of 

 sodium or lithium.* A similar contrasting behavior of different 

 cations of chlorides was noted by Harden (17), who found that 

 potassium chloride and ammonium chloride cause a definite degree 

 of fermentation in inactivated yeast, while sodium chloride has no 

 effect. He says: "A specific difference in relation to alcoholic 

 fermentation exists between the ions of sodium on the one hand and 

 of potassium and ammonium on the other hand." SchReixer and 

 Sullivan (29) found that potassium salts retard oxidation by the 

 roots of plants. 



