FERMENTATION 191 



from the cells that produce them. There seems 

 thus an important distinction to be made between 

 organized ferments, those acting apparently with- 

 in the living cell, and unorganized ferments, like 

 the salivary diastase, which is secreted by a 

 living cell but remains active after leaving the 

 cell. It will be seen that this distinction cannot 

 be maintained. 



Extraction of Diastase from Germinating Barley. 1 

 Crush freshly germinating barley in a mortar 

 with about half its weight of water. Keep the 

 mass two hours at 35-40 C. Squeeze out the 

 watery extract in a press, or strain by strong 

 pressure through a linen cloth. Add excess of 

 alcohol. 



Diastase will be precipitated. It may be puri- 

 fied by dissolving it in water and reprecipitating 

 with alcohol. 



Add a little diastase to 10 c.c. starch paste, 

 colored blue with iodine. The starch will be con- 

 verted to sugar. The blue color will disappear. 



It appears, therefore, that ferment action is 

 not dependent on the life of the cell that secretes 

 the ferment. 



Specific Action of Ferments. The question 

 now arises whether the diastase acts only to 



1 Payen and Persoz: Aunales de cliimie et de physique, 

 1833, liii, p. 78. 



