1 88 Nutrition and Tannase Production 



eludes the enzymes which are formed only under several different forms of 

 nutrition, while the third group includes such enzymes as are formed only 

 when the substance on which the enzyme acts is present in the culture solu- 

 tion. 



Butkewitsch" also has shown that nutrition has an influence upon the 

 secretion of the gelatin-dissolving enzyme by Aspergillus and PenidlUum. 



III. METHODS OP EXPEBIMENTATION. 



In all of the experiments upon the influence of nutrition on the 

 production of the enzyme the organisms were cultivated in a syn- 

 thetic nutrient solution, the inorganic composition being that of 

 Czapek's" formula. Throughout this paper the solution has been 

 designated for convenience solution B and is as follows: 



Magnesium sulphate (oryst.) 0.5 gram 



Dibasic potassium phosphate 1.0 gram 



Potassium chloride 0.5 gram 



Sodium nitrate 2.0 grams 



Distilled water 1000 cc. 



AH cultures were grown at a temperature of 28° or 30°. The 

 fungus felt, when formed and before spore production, was removed 

 from the nutrient solution, as it has been shown by Malfitano" 

 that the most abundant secretion of enzymes into the culture solu- 

 tion takes place just after spore formation. The felt after removal 

 was treated according to Albert and Buchner's method for the pre- 

 paration of "Acetondauerhefe," as described by Dox,i^ though in 

 the method here employed the felt was not run through a hashing 

 machine. After the mycelium was dry, it was pulverized in a 

 mortar and then placed in a vial until its enzymatic activity was 

 to be determined. 



For determining the presence of the enzyme or the relative 



"W. Butkewitsch: Umwandlung der Eiweisstoffe duroh die niederen 

 Pilze im Zusammenhange mit einer Bedingungen ihrer Entwickelung, 

 Jahrh. f. wiss. Boi., xxxviii, pp. 147-240, 1903. 



» Quoted from A. W. Dox: The Intracellular Enzymes of Penicillium 

 and Aspergillus, U. S. Dept. of Agric, Bureau of Animal Industry, Bulletin 

 120, 70 pp. ,1910. 



"G. Mamtano:,La proteolyse chez 1' Aspergillus niger, Ann. de I'lnst 

 Pasteur, xiv, pp. 60-81, 1900. 



" A. W. Dox: The Intracellular Enzymes of Penicillium and Aspergillus 

 loc. cil. ' 



