Lewis Knudson 187 



Btlsgen' showed that Aspergillus oryzae.on bouillon, as well as in a sugar- 

 containing solution, formed the enzyme diastase. According to Pfeffer," 

 Penicillium glaucum did not secrete diastase in the presence of 10 per cent 

 sugar and, even when only 1.5 per cent sugar was present, the starch was only 

 slightly attacked. Aspergillus niger behaved differently, producing dias- 

 tase even in the presence of 30 per cent cane sugar. Employing a nutrient 

 solution containing 0.25 per cent of soluble starch Katz" found that starch 

 was saccharified by Penicillium glaucum. The addition of 2 per cent grape 

 sugar or 1.5 per cent cane sugar prevented the formation of the diastase. An 

 addition of 1.5 per cent cane sugar depressed the formation of the diastase, 

 while an addition of 0.05 per cent had no effect. Lactose and maltose in a 

 3 per cent concentration decreased the rate of starch transformation, while 

 a 10 per cent concentration still further depressed the formation of diastase. 

 A 4 per cent addition of erythrodextrin had no effect whatsoever in protect- 

 ing the starch. Neither did a 10 per cent addition of quinic acid, 4 per cent 

 glycerin or 2 per cent potassium tartrate have any effect upon the secre- 

 tion of the diastase. The addition of peptone to the solution increased the 

 secretion of the diastase. With Aspergillus niger the growth on starch 

 nutrient solution was slow, and five days were required for the transforma- 

 tion of the starch. The addition of 1.5 per cent cane sugar decreased the 

 time to two days, 15 per cent sugar increased the time of transformation by 

 one day and 30 per cent sugar increased the time by two days. Bacterium 

 megatherium behaved much the same as Penicillium glaucum. 



Dox" has shown that the carbohydrate-splitting enzymes, amylase, 

 inulase,.rafflnase, sucrase, maltase and lactase are formed in Penicillium 

 camemberti, regardless of the carbohydrate which has served as the source 

 of carbon in the nutrient solution. The amount of the particular enzyme 

 could be increased, however, by cultivating the organism on the correspond- 

 ing carbohydrate. Likewise, other enzymes -are formed independently of 

 the presence in the nutrient solution of the corresponding substance on 

 which the enz3rme acts. 



According to Went," the ten enzymes which he investigated in Monillia 

 sitophila could be divided into three groups according to the influence of 

 nutrition on their formation. The first group includes those which are 

 formed in slight amounts regardless of the nutrition, the second group in- 



' M. Busgen: Aspergillus oryzae, Ber. d. deutsch. hot. Oesellsch., iii, pp. 

 66-77, 1885. 



" Quoted from R. Green : The Soluble Ferments and Fermentation, p. 32. 



" J. Katz: Die regulatorische Bildung von Diastase durch Pilze, Jahrb. 

 f. wiss. BoL, xxxi, pp. 599-618, 1898. 



12 A. W. Dox: The intracellular Enzymes of Penicillium and Aspergillus, 

 U. S. Dept. of Agric, Bureau of Animal Industry, Bulletin 120, 70 pp., 



1910. 



" F. C. Went : Ueber den Einfluss der Nahrung auf die Enzymbildung 

 durch Monillia Sitophila (Mont.), Sacc, Jahrb. f. wiss. Bot., xxxvi, pp. 

 611-664, 1901. 



