

PUTREFACTION PRODUCTS. 163 



C(Q-SOaK), 



CH 

 NH 



and eliminated as such in the urine. 



Indican may be decomposed by treatment with concentrated hy- 

 drochloric acid (see tests on page 280) into sulphuric acid and in- 

 doxyl. The latter body may then be oxidized to form indigo-blue 

 thus: 



C(OH) /\_ _CO OC__ _/\ 



+ 20=1 II | I | +2H 2 



^A/c=c\A/ 



NH NH 



Indoxyl. Indigo-blue. 



This same reaction may also occur" under pathological conditions 

 within the organism, thus giving rise to the appearance of crystals 

 of indigo-blue in the urine. 



Skatole is likewise changed within the organism and eliminated 

 in the form of a chromogenic substance. Skatole is, however, of 

 less importance as a putrefaction product than indole and ordinarily 

 occurs in much smaller amount. The tryptophane group of the 

 protein molecule yields the indole and skatole formed in intestinal 

 putrefaction, but the reasons for the transformation of the major 

 portion of this tryptophane into indole and the minor portion into 

 skatole are not well understood. Indole is more toxic than skatole. 



Phenol occurs in fairly large amount in certain abnormal con- 

 ditions of the organism, but ordinarily the amount is very smalL 

 It is probably derived from the tyrosine group of the protein mole- 

 cule. Phenol is conjugated in the liver to form phenyl potassium 

 sulphate and appears in the urine in this form (Baumann and 

 Herter). Para-cresol occurs in the urine as cresyl potassium sul- 

 phate. 



Regarding the claim of Nencki that methyl mercaptan is formed 

 as a gas during intestinal putrefaction it is an important fact that 

 Herter 1 has been unable to detect the mercaptan in fresh feces. He 

 is therefore, not inclined to accept the theory that methyl mercap- 

 tan is formed in ordinary intestinal putrefaction but believes that 

 it may be formed in exceptional cases. Hydrogen sulphide is, how- 

 ever, formed in all cases of intestinal putrefaction. 



1 Herter : Bacterial Infections of the Digestive Tract, p. 227. 



