Nov. 15, 1919 



Do Mold Spores Contain Enzyms f 



201 



with the 10 per cent solution and form an adequate basis for establishing 

 the fact that the spores of Aspergillus niger contain invertase. 



Table V. — Summary of enzymic activity of spores of Aspergilltis niger 



» Original considered as 100 per cent. 



*> Corrected to 10 cc. 



In Table V the data previously presented are summarized in such a 

 way as to make evident the correlations which are of interest. For 

 example, it will be readily observed that with a given quantity of 

 inoculum in a sugar solution of definite concentration there is a pro- 

 gressive decrease in polarization accompanied by an increase in reducing 

 sugars with an increase in the incubation period. Again, it may be 

 noted that increasing the inoculum causes practically a proportional 

 decrease in polarization and a corresponding increase in reducing sugars. 

 This lends further support to the evidence brought forward that spores 

 contain enzyms, for it is precisely under such circumstances that a ' 

 relationship is established between the number of spores and the amount 

 of enzymic activity. While the data presented do not establish such a 

 correlation with mathematical accuracy, one may assume that the 

 number of spores whose walls become ruptured would be somewhat 

 variable in quantity, and consequently a progressive increase in enzymic 

 activity may be seen to accompany an increase in the number of 

 spores. 



It is especially interesting to note that 20 cc. of spores reduced the 

 polarization of a 10 per cent sugar solution in 4 days in such a way 

 as to indicate the loss of 50 per cent of the original sucrose present. 

 This inoculum accounted for the loss of 22 per cent of the original sucrose 

 content in 24 hours. The increase in reducing sugars is even more 

 striking, as seen in the last column of Table V, where, in the cases men- 

 tioned above, the amounts were increased 4,080 and 900 per cent, respec- 

 tively, compared with the original percentage taken as 100. 



When the inoculation of a 10 per cent sugar solution with 10 cc. of 

 spores is compared with a similar inoculation of a 20 per cent sugar 

 solution, it will be seen that in 24 hours the amount of reducing sugars 

 in the latter case was about double that in the less concentrated solution. 



