196 



Nutrition and Tannase Production 



A26 was used, and as culture vessels liter flasks were employed. 

 Into each flask were placed 365 cc. of the solution, and to it were 

 added the sugar and other reagent, or the sugar was omitted and 

 some other carbon compound substituted for it. The solutions 

 were sterilized, inoculated and incubated at a temperature of 28°C. 

 The felt was removed just before spore production and treated in 

 the manner previously described. 



To determine the presence of tannase, 0.3 gram of the powdered, 

 dried mycehum was introduced into 100 cc. of a 0.75 per cent solu- 

 tion of tannic acid, to which had been added as an antiseptic 2 

 cc. of chloroform. After incubation at 31° for one week, the solu- 

 tions were analyzed for gallic acid. The results obtained are given 

 in table VI. 



TABLE VI. 



Penieilliwm sp. 



COMPOSITION OP NUTRIENT SOLUTION 



Solution A -\- 25 grams cane sugar 



Solution A + 25 grams cane sugar 5 cc. -^ HCI. 



Solution .4 + 15 grams corn starch 



Solution A + 25 grams glycerin 



Solution A + 25 grams gallic acid 



Solution A + 25 grams tannic acid 



The control contained 0.202 gram gallic acid at the beginning 

 and at the end of the incubation. 



The gaflic acid stimulated the formation of the enzyme only one- 

 fom'th as much as did the tannic acid. Slight acidity had no 

 effect in stimulating the production of the enzyme. Glycerin 

 and starch, both of which are relatively poor food compounds, 

 were supphed, and if enzymes are stimulated to formation by con- 

 ditions approaching starvation, as suggested by Wortman,^' then 

 the tannase should have developed; but the results were negative. 



An experiment similar to that above was made with Asper- 

 gillus niger, 400 cc. of solution being used and the methods of exper- 

 imentation the same as before. The results obtained are as fol- 

 lows : 



28 KHsPOi. 0.5 gram; KNO3, 1 gram; MgSo,, 0.25 gram; Distilled water, 

 100 cc. 

 " Loc. cit. 



