THE FOOD AND DIGESTION 



attack any proteid which is not absorbed splitting it up and 

 forming among other substances a series of aromatic bodies, 

 of which the chief are indol, skatol, and phenol. 

 Indol is a derivative of ethyl-amido-benzene. 



Amido-benzene. 



H H H 



\ I I I 

 TT x N C C H Ethyl-amido-benzene. 



A A 



In Skatol a hydrogen of the ethyl of indol is replaced 

 by CH 3 . 

 Phenol is 



O H 



By taking embryo guinea-pigs at full time from the uterus 

 and keeping them with aseptic precautions, it has been shown 

 that the absence of micro-organisms from the intestine does 

 not interfere with digestion. 



The most important and abundant organism present in 

 the intestinal tract is the bacillus coli communis, which has 

 a certain power of splitting proteids and a marked action 

 in producing acids from sugars. Its presence in water is 

 generally considered indicative of sewage contamination. 



