572 Drs. T. A. Henry and S. J. M. Auld. [July 22, 
brewers’ yeast by a slight modification of Buchner’s process we are indebted 
to Dr. A. Harden of the Lister Institute of Preventive Medicine, to whom 
we take this opportunity of expressing our thanks. 
In the experiments with yeast juice on amygdalin, the flasks were plugged 
with cotton wool, their contents having been previously rendered antiseptic 
by the addition of a few drops of toluene. The temperature used was that 
found experimentally to be the best, viz., 40°. 
Three different preparations of yeast juice were employed, and these, as the 
following table shows, varied considerably in activity. 


| Weight of i Fae t Time required for 
Yeast juice. amygdalin used in ean "d a oan commencement 
20 c.c. of water ye of decompositi 
| C. : position. 



gramme. C.c. hours 
Specimen Nowdier.-.0.....-.. 1 5 23 
oe ga | ee ae 1 5 36 
¥ NOS ecitert sgn 1 5 120 


Dilution of the juice had no very striking effect on the rate of decomposi- 
tion, but the addition of a little water seemed to slightly accelerate the 
activity, and further addition of water to slightly diminish it, as the following 
table shows. 
Weight of Volume of Volume of iascarg teas io 
amygdalin used east juice water used commencement 
Je : y Ue ; of decomposition. 

gramme. C.C. | c.c hours. 
1 5 | 5 22:°5 
1 5 10 21 
aL 5 15 21°5 
1 5 20 23 
| | 5 25 24, 

The products of the action of yeast juice on amygdalin are the same as 
those of yeast itself, viz., benzaldehyde, hydrocyanic acid, alcohol and carbon 
dioxide. 
Influence of Hydrocyanic Acid on the Glucosidolytic Action of Yeast Tuice, 
That hydrocyanic acid of moderate strength has comparatively little 
disturbing action on the glucosidolytice activity of yeast is obvious from the 
fact that the decomposition of amygdalin can proceed to the extent of 70 per 
cent. of the amount of glucoside used. It will be seen from the following 
