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weight is reached, i. e. the stronger the development of the fungus, 

 the more of thèse inhiblting substances are produced. As the develop- 

 ment is dépendent on the foodsupply, the latter must be con- 

 sidered to be the primary cause. After some time, thèse mhibi- 

 tory substances are broken down or assimilated by the fungus, or 

 removed m some other way. In any case, the diastase is again set 

 free and now we fmd there appears to be a sudden rise. So for the 

 first time, we are m a position to really estimate ail the diastase that 

 has been produced by Aspergillus niger. So much enzyme is set 

 free in this way that the curve shows a second maximum, which 

 is much higher than the first and remains almost at the same level 

 for a long time\ We can also see now why the curves, which 

 represent the production of diastase in the mycélium + culture 

 solution (as for example in fig. 12 A), follow a course from which 

 very little can be learnt. The enzyme in the mycélium is not under 

 the influence of the inhibitory substances in the solution and it 

 therefore partially counteracts the fall which is seen, when the 

 culture solution is observed alone; that is why it seems to disturb 

 the course of the curve to some extent, when it is drawn to repre- 

 sent the amount of diastase, found in both the culture solution and 

 the mycélium. 



We might also imagine that the sugars, which are still présent 

 in the solutions, disturb the chemical equilibrium of the reaction 

 and retard the hydrolysis in this way. This really takes place, when 

 maltose is added to a mixture of diastase and starch solution. In 

 an experiment I obtained the following results. I used a solution 

 of diastase, which completely hydrolysed a given amount of starch 

 m 185 secs. If the mixture contained 1% maltose, it took 440 secs. 



Perhaps we may look upon the sudden rise of diastase concentration on the 

 last day of observation of the séries A G, table 1 B, as the beginning of this "setting 

 free" of the enzyme. The dry weight in this séries was very high: 1217 ni.Gr., 

 so that we may imagine that so much of the inhibitory substances was secreted, 

 that almost ail the diastase had been neutralised, but that in the end the setting 

 free began, so that on that last day a rather large amount of diastase was found. 

 This single observation however, does not suffice to entitle us to this conclusion. 



