194. 



Nutrition and Tannase Production 



TABLE III. 



Aspergillus niger. 

 Effect of concentration of sugar on production of tannase; using solution B + 

 2 per cent tannic acid + cane sugar. Period of incubation, ninety hours. 



sugar, the tannic acid being maintained at a constant figure, there 

 is a decrease in the amount of the enzyme produced. 



In order to verify the above results another experiment was 

 made along substantially the same lines with Aspergillus niger. 

 To test the tannase activity of the dry mycelium 100 cc. of a 0.5 

 per cent tannic acid solution were used to which was added 1 per 

 cent toluene. In each case 0.05 gram of the powdered myceliimi 

 was employed. The cultures were made in duplicate and the 

 determinations hkewise. One set was incubated at 24°C. for 

 four days and the second set at the same temperature for six days 

 before analyses were made for gallic acid. In the following table 

 there is giyen the composition of the nutrient solutions used and the 

 increase in the gaihc acid resulting, which increase of course is a 

 measure of the tannase activity of the various cultures. 



TABLE IV. 



Aspergillus niger. 

 Effect of concentration of sugar on production of tannase; using solution 

 B + B per cent tannic acid + cane sugar. 



