592 Prof. H. E. Armstrong and Mr. H. W. Gosney. [June 13, 



Table showing the Effect of the Presence of Four Equivalents of various 

 Acids on the Action of - 5 grm. of treated Enzyme on 10 c.c. M/20 

 Solution of Succinic Ether, i.e., in N/5 Acid Solutions. 



Percentage hydrolysed 



Glycine 71 - 



Acetic acid 63 "4 



Succinic acid 62"0 



No acid 62'0 



Butyric acid 50'9 



Malic acid 41 '3 



Citric acid 29 6 



Tartaric acid 15 "8 



Sulphuric acid 0"8 



To hydrolase succinic ether, a relatively large amount of the enzyme is 

 required. Thus on digesting 1 grm. of the Lipase powder with 10 c.c. of an 

 M/20 solution of ethylic succinate (0 - 087 grm.) during 48 hours, the ethereal 

 salt was completely hydrolysed : but \ grm. of the powder was insufficient. 



The enzyme is only slightly, if at all, affected by the action and will 

 hydrolyse fresh ester but its action on oil is somewhat impaired. Thus 

 when 0'5 grm. of enzyme was allowed to act during 20 hours on four different 

 quantities, each 10 c.c. M/20 ethylic succinate, in succession, hydrolysed 



52 - per cent, during 1st use 



50-5 „ „ 2nd „ 



48-4 „ „ 3rd „ 



47-6 „ „ 4th „ 



The once used enzyme, however, caused only 29'5 per cent, hydrolysis of 

 5 grm. of oil, the fresh enzyme causing about 66 per cent, in the same time. 

 This lipoclastic weakening of the enzyme is possibly due to a loss of 

 emulsifying power. 



Whatever the amount of enzyme present, the amount of action appears to 



be approximately proportional to the amount of ethereal salt in solution. 



Thus 0'5 grm. enzyme acting during 20 hours at 30° C. hydrolysed : — 



0-0096 grm. ethereal salt in 10 c.c. M/100 solution 

 0-0234 „ „ 10 „ M/50 



10 „ M/33-3 



0-0327 

 0-0487 

 0-0710 

 0-0913 



10 „ M/20 

 10 „ M/15 



10 „ M/10 



But apparently, when undissolved ethereal salt is present, the amount of 

 action is not greatly in excess of that effected in saturated solution. Thus, 

 on digesting 5 grm. of succinic ether with 5 c.c. of water and 0-5 grm. of 

 enzyme during 20 hours, only 0'205 grm. was hydrolysed — or about twice as 

 much as when an M/10 solution was used. 



