1910.] 



Studies on Enzyme Action. 



361 



Time of 

 action. 



Initial rotation. 



Rotation after 

 addition of 

 soda. 



Change in 

 rotation. 



hours. 



0 



c 



o 



0 



— 3 -40 



— 3 '36 



+ 0 -04 



1 



-3 12 



-3 11 



+ 0-01 



2 



-2-83 



-2 -80 



+ 0 '03 



3 



-2 -57 



-2 -55 



+ 0-02 



3 -5 



-2 -43 



-2-43 



0-0 



5 



-2 -10 



-2 -11 



-0 -01 



6 



-1 -80 



-1-81 



-0 01 



7 



-1 -65 



-1 -65 



0 0 



8 



-1 -51 



-1-50 



+ 0-01 



25 



-0-27 



-0-21 



+ 0-06 



The differences observed in this case were too small to be of any positive 

 value. Further experiments were carried out as follows : — 



A solution of 7'4143 grammes of phaseolunatin in water occupying 75 c.c. 

 at 25° was mixed with 75 c.c. of a solution of phaseolunatase, also at 25°. The 

 latter solution was prepared by shaking 100 c.c. of the cloudy extract with 

 20 c.c. of alumina cream and filtering ; this treatment gave a clear solution of 

 the enzyme, highly active towards phaseolunatin. A 2-decimetre jacketed 

 polarimeter tube was filled with the mixture of glucoside and enzyme and the 

 rotation observed at 25°; then a drop of a solution of soda was added and 

 the rotation again determined. Meanwhile the main bulk of the liquid 

 (which was now an M/5-solution of the glucoside) was heated to 37° and kept 

 at this temperature, samples being withdrawn at intervals and examined in 

 the manner described in the case of the initial experiment. The following 

 results were obtained : — 





Time of 

 action. 



Initial rotation. 



Rotation after 

 addition of soda. 



Mean change 

 in rotation. 





Hours. 



o 





1 



o 



1st experiment... 



0 



-4-24 



-4-21 



+ 0-03 





1 



-3 -99 



-3 -95 



+ 0-04 





2 



-3 -57 



-3 -51 



+ 0-06 





3 



-3 -26 



-3 -23 



+ 0-03 





4-5 



-2 -81 



-2 81 



0-0 





5 



-2 -56 



-2-55 



+ 0-01 





6 



-2 -31 



-2 -31 



0-0 





7 



-2 -04 



-2 -11 



-0-07 





24 



-0-27 



-0 -36 



-0-09 



2nd experiment. . . 



0 



-3 -76 



-3 -74 



+ 0-02 





1 



-3 -66 



-3 -65 



+ 0-01 





1 -5 



-3 -53 



-3 -50 



+ 0-03 





2-5 



-3 -27 



-3 -26 



+ 0-01 





4 



-2 -90 



-2 -90 



0-0 





5-5 



-2-61 



-2-66 



-0-05 





6-5 



-2 -45 



-2 -49 



-0 -04 





24 



-0-35 



-0 -44 



-0-09 



