Nov. 15, 1919 



Do Mold Spores Contain Enzyms 9 



199 



germination or contamination. Thus the results after 24 hours con- 

 firmed those obtained after 3 hours' incubation, and we must conclude 

 that the spores of Aspergillus niger had released sufficient of the enzym 

 invertase to carry forward the inversion of sucrose already noted. 



Finally, after the addition of three drops of chloroform and another 

 incubation, the flasks were analyzed at the end of four days. The 

 results are to be found in Table III. 



Table III. — Analyses of 10 per cent sugar solutions inoculated with spores of Aspergillus 



niger 



[Four days' incubation] 



Compared with the previous analyses the control flasks — sterile water 

 heated to 63° and 100° C. and spores heated to 100° — show a slightly 

 higher and somewhat less consistent polarization. This is undoubtedly 

 due to evaporation, the flasks having been plugged with cotton. That 

 the discrepancies are negligible is evidenced by the uniformity in amount 

 of reducing sugars present, which represent the true criterion of inver- 

 sion. Where 10 cc. of spores heated to 63° were employed, the polar- 

 ization was reduced to 24.1 as compared with 37.3 in the control, a loss of 

 13.2 or a decrease of 3.31 per cent sucrose. The reducing sugars indicate 



