172 



Tannic Acid Fermentation 



of the gallic acid despite the fact that tannic acid is present in the 

 solution. 



A comparison of tables III and IV is of interest. The one 

 experiment with a synthetic solution and the other with the infu- 

 sion were conducted at the same time and under identical condi- 

 tions as regards sterilization, inoculation and incubation. More- 

 over, the tannic acid and the gallic acid content of the culture 

 solutions are nearly the same. 



In table V, only the duration of experiment, decrease of tannic 

 acid, the loss or gain of gallic acid and the dry weights of the fungus 

 produced, are included, 



Ti&LE V. 



DURATION 



days 



Solution B -{- 1.603 gbams Tannic 

 Acid + 2.100 grams Gallic Acid 



LOSS OF 

 TANNIC ACID 



LOSS 

 OR GAIN OF 



GALLIC ACID 



DRY 



WEIGHT OF 

 FUNGUS 



Infusion of Gall Nuts: 

 Tannic Acid = 1.627 grams 

 Gallic Acid = 1.797 grams 



LOSS OF 

 TANNIC ACID 



GAIN OF 

 GALLIC ACID 



DBT 



WEIGHT OF 

 FUNGUS 



Aspergillus niger. 



PenicilKum sp. 



0.307 



092 

 128 

 603 



1.415 



+0.253 

 +0.760 

 +0.590 

 +0.674 



+0.450 



0.043 

 0.157 

 0.110 

 0.171 



0.151 



It is interesting to note that in the synthetic solution the gallic 

 acid decreased after the eighth day, while in the gall nut infusion 

 it showed at that time a marl^ed increase, and this increase was 

 maintained thereafter. In the synthetic solution on the eighth 

 day there was a loss of 0.286 gram of gallic acid, while in the gall 

 nut infusion there was a gain of 0.703 gram of gallic acid, and in 



