198 



Nutrition and Tannase Production 



TABLE VIII. 



Aspergillus niger. 



COMPOSITION OF NUTRIENT SOLUTION 



GALLIC ACID INCREASE 



Solution B + 10 per cent sugar + 35mginZnS04.H20. . 



Solution B + 10 per cent sugar + 20 mgm salicylic acid 



Solution B + 10 per cent sugar + 1 gram gallic acid . . . 



Solution B + 10 per cent sugar + 200 mgm. methyl sali- 

 cylate 



Solution B + 10 per cent sugar + 200 mgm. ethyl sali- 

 cylate 



Solution B + 10 per cent sugar + 50 mgm. methyl sali- 

 cylate 



Solution 5 + 10 per cent sugar + 50 mgm. ethyl sali- 

 late 



None 

 None 

 None 



None 



None 



None 



None 



Pottevin'" states that tannase has the property of hydrolyzing 

 methyl and ethyl salicylate. In my cultures the methyl or ethyl 

 salicylate did not incite the development of the enzjmie. The 

 amount of salicylate present, however, was small. These concen- 

 trations may have been too weak to stimulate the production of 

 the enzyme but probably the hydrolysis of these two substances is 

 due to another enzyme. Salicylic acid also was used because of 

 its relation to gallic acid, salicylic acid being a monohydroxy- 

 benzoic acid, while gallic acid is a trihydroxybenzoic acid. The 

 former was necessarily used at a very low concentration, and was 

 without effect. The zinc sulphate was used at a concentration 

 which is stimulating to the fungus growth, as shown by Elchards,'i 

 but no formation of the tannase resulted. 



Since in some of the experiments tannase was not produced 

 when the organism was grown in a solution with the carbon sup- 

 plied as cane sugar and gallic acid, an experiment was made with 

 the carbon supplied only as gaUic acid. At the same time experi- 

 ments were made to determine the influence of certain glucosides. 

 Solution B was used, and 500 cc. of it placed in each of three liter 

 flasks. These were plugged and sterilization made at 115° for 

 ten minutes. To each of the three flasks was added gallic acid, 

 amygdalin and saUcin, respectively, and the culture solutions 



'" Loc. cit. 



3' H. M. Richards: Die Beeinflussung des Wachstums einiger Pilze durch 

 chemische Reize, Jahrb. f. wiss. Bot, xxx, pp. 665-88. 



