INTESTINAL PUTREFACTION. 



The chief interest in the study of the effects produced 

 by bacteria upon protein matter lies in the direction of the 

 additional insight which can be obtained into the consti- 

 tution of the protein molecule. This becomes possible 

 .since the microorganisms effect a cleavage of the mole- 

 cule which, while similar in character to that exerted by 

 the digestive enzyme, is more vigorous and deep-seated 

 than even trypsin itself; and the products obtained are so 

 simple in composition and structure that they have yielded 

 easily to investigation. 



The most important substances which result from bac- 

 terial decomposition of proteins may be divided as follows : 



1. Tyrosine and its derivatives, the phenols, aromatic 

 acids, and oxy-acids (e.g., oxyphenylpropionic and oxy- 

 phenylacetic acids). 



2. Indole and its derivatives, skatole, skatole-carbonic 

 acid, and tryptophane. 



3. Fatty acids and derivatives, leucine, etc. 



4. Sulphur derivatives and gases, hydrogen sulphide, 

 methyl mercaptan, CEU, CC>2, and NHs. 



5. Proteoses and " peptones " are present in small 

 amounts as intermediary products. 



The following method is employed for the preparation 

 and separation of the various products. It lends itself also 

 for demonstration purposes, and the different distillates 

 can be studied individually. 



62 



