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New YORK AGRICULTURAL EXPERIMENT STATION. 53 
tory method of estimating the possible significance of such 
colonies is by a discussion of the relative chemical changes in 
cheese in which they did, and in which they did not appear. This 
will be presented in a later bulletin upon the relation of enzyms 
to cheese-ripening. 
EPRECT OF CHLOROFORM UPON ENZYM ACTION. 
Since so little is known regarding the constitution of enzyms, 
it is not to be expected that the mode of action of the chloroform 
upon enzyms will be clearly understood. Our knowledge here 
rests principally upon observed variations in the rate of action 
of enzyms under different circumstances. In such cases it is 
often impossible to determine whether these variations are due 
to the action of the chloroform directly upon the enzym or indi- 
rectly by changes induced in the substance upon which the 
enzym acts. 
INFLUENCE OF OXYGEN UPON THE ACTION OF CHLOROFORM. 
Malfitano(1) found that the influence of chloroform upon . 
enzym action was markedly affected in some cases by the ab- 
sence of oxygen. Thus the autodigestion of bacteria was stimu- 
lated by the addition of a drop of chloroform to a cotton stop- 
pered tube containing a suspension of the organisms, while this 
digestion did not take place if the air was removed and the tube 
sealed at the time the chloroform was added. He reasoned that 
this difference in digestion was due to the absence of oxygen, 
since the same inhibition of the enzym action occurred when the 
culture tube was filled with hydrogen before sealing. 
In the case of pancreatic juice under similar conditions, chlo- 
roform noticeably hindered the action of the enzym and, in the 
absence of oxygen, practically stopped digestion. While the 
presence of chloroform weakened the action of pepsin, there was 
no appreciable difference in its rate of digestion in the presence 
-and in the absence of oxygen. Fibrin in a physiological salt 
solution digested rapidly and quite completely in the presence of 
oxygen and an excess of chloroform, while a second portion of 
the same fibrin under parallel conditions, except that the con- 
tainer was sealed after the removal of the air, digested but little. 
In our study of milk enzyms we have necessarily conducted 
our experiments in sealed containers, since the rate of action was 
slow and, unless closely confined, the chloroform would evap- 
' orate, leaving the milk or cheese open to the action of bacteria. 
