PHYSIOLOGICAL CHEMISTRY. 



The ferments present are evidently of two types ; one resem- 

 bling the invertase of cane sugar already described, while the 

 other is of the maltase type. 



The Secretion from Brunner's Glands. The collection of 

 the product from these small glands offers considerable tech- 

 nical difficulty, and until recently no very clear statements 

 were found in the literature as to the exact nature of the secre- 

 tion. By taking special precautions, however, Glaessner suc- 

 ceeded in securing the secretion free from other fluids, and has 

 found that it possesses marked proteolytic properties in solu- 

 tions of all reactions. The digestion of protein is carried to 

 the stage where tryptophane may be easily recognized. The 

 name pseudopepsin may be given to the active enzyme. 



Erepsin. Comparatively recently a ferment called erepsin 

 has been described by Cohnheim in the intestinal juice. It 

 does not digest the true proteins but has the power of splitting 

 albumoses and peptones as far as the mono and diamino acids. 

 This enzyme may have importance as an intercellular ferment 

 and be concerned in preparing the protein digestive products 

 for subsequent synthesis. 



Enterokinase. This name has been given to a ferment- 

 like body which occurs in the intestinal juice and which has 

 the power of activating trypsinogen. Without the presence 

 of this activator it is held by some recent writers that trypsin 

 is not formed and therefore cannot digest protein. The en- 

 terokinase is not a digestive agent itself. 



In the brief discussions of the last few chapters it has been 

 shown in a general way how the important classes of food 

 stuffs through the action of enzymes in different parts of the 

 body are gradually brought into a condition suitable for as- 

 similation and absorption. They have undergone digestion 

 and are ready to be carried through the intestinal walls into 

 the blood stream to be used as food for the building up of 

 the body or as oxidation material for the production of me- 

 chanical energy and heat. These various digestive processes 

 differ in many ways, but they have this important element in 



