506 



HYDROLYTIC FERMENTS. 



9. The hydrolytic ferments have recently been called Enzymes by W. 



Kiihne, in order to distinguish them from organised ferments, such as yeast. The 

 enzymes, hydrolytic or organic ferments, act only in the presence of water. They 

 act upon certain bodies causing them to take up a molecule of water. They all 

 decompose hydric peroxide into water and O. They are most active between 30- 

 35C., and are destroyed by boiling, but when dry they may be subjected to a 

 temperature of 100 without being destroyed. Their solutions, if kept for a long 

 time, gradually lose their properties and undergo more or less decomposition. 



[Table showing the unorganised ferments present in the body, and their 

 actions: 



Fiuid or Tissues. 



Saliva, . 



Ferment. 



1. Ptyalin, . . . 

 (See also p. 296.) 



Actions. 



Converts Starch chiefly into Maltose. 



Gastric Juice,/ 



1. Pepsin, . . . 



2. Milk-curdling, 



3. Lactic Acid Ferment 



4. Fat-splitting, 



Converts Proteids into Peptones in an 

 Acid Medium, certain by-product; 

 being formed (p. 331). 



Curdles Casein of Milk. 



Splits up Milk-sugar into Lactic Acid. 



Splits up Fats into Glycerin and 

 Fatty Acids. 



Pancreatic 

 Juice, . 



1. Diastatic or 



Amylopsin, . 



2. Trypsin, . . . 



3. Emulsive, 



4. Fat-splitting or 



Steapsin, 



5. Milk-curdling, . 



Converts Starch chiefly into Maltose. 



Changes Proteids into Peptones in 

 an Alkaline Medium, certain by- 

 products being formed (p. 341). 



Emulsifies Fats. 



Splits Fats into Glycerin and Fatty 

 Acids. 



Curdles Casein of Milk. 



Intestinal 

 Juice, 



Blood, . . 



Chyle, . . 

 Liver, . . 

 Milk, . . . 

 Most Tissues, 



1. Diastatic, 



2. Proteolytic, . 



3. Invertin, 



4. Milk-curdling, 



! 



Does not form Maltose, but Maltose is 



changed into Glucose (p. 370). 

 Fibrin into Peptone (?). 

 Changes Cane- into Grape-Sugar. 

 (?in Small Intestine.) 



> Diastatic Ferments. 



Muscle, 

 Urine, 



Pepsin. 



Blood, 



Fibrin-forming 

 Ferment. 



(Modified from W. Roberts).] 



