THE AROMATIC CONSTITUENTS OF THE URINE. 261 



The whole operation can be finished in less than fifteen minutes ; 

 indeed, it should be finished at once, as the colored product obtained 

 by the interaction of kreatinin and picric acid is not very stable. 



THE AROMATIC CONSTITUENTS OF THE URINE. 



It has been pointed out in a preceding chapter that during the 

 process of intestinal putrefaction various aromatic bodies are formed 

 from the albumins of the food or their products of digestion, and 

 are then absorbed and eliminated in the urine, either as such or in 

 combination with sulphuric acid, glucuronic acid, or glycocoll. 

 Some of these bodies, such as indol and skatol, may be regarded as 

 specific products of putrefaction ; while others or closely related 

 substances represent radicles which exist as such in the 

 albuminous molecule. We consequently recognize two sources 

 of the aromatic bodies which are found in the urine, viz., the 

 aromatic bodies which enter into the composition of our diet 

 as such, and those which result from the destruction of albumins 

 through the activity of micro-organisms. Under certain patholog- 

 ical conditions, further, substances of this character may also be 

 formed in the body proper, owing to degenerative changes, which 

 may or may not be the result of bacterial action. Under normal 

 conditions, however, this source scarcely enters into consideration. 



The Conjugate Sulphates. 



Paracresol, phenol, hydroquinon, pyrocatechin, indol, and skatol 

 are largely eliminated in the urine in combination with sulphuric 

 acid as sodium or potassium salts. But while paracresol and its 

 derivatives combine with sulphuric acid directly, indol and skatol 

 are previously oxidized to indoxyl and skatoxyl, as has been shown. 

 Conjointly the resulting compounds are spoken of as the conjugate 

 or ethereal sulphates of the urine. Their daily excretion in man 

 corresponds to about one-tenth of the mineral sulphates, viz., from 

 0.094 to 0.620 gramme, under normal conditions. Increased 

 amounts are observed when from whatever cause the intestinal 

 putrefaction is increased. It is to be noted, however, that the ratio 

 between the individual substances is even normally not constant, 

 and it seems that the relative preponderance of the one over the 

 other is primarily referable to the extent to which individual groups 

 of micro-organisms are active. In some instances we may thus find 

 that the increase in the conjugate sulphates is referable to an increased 

 production of indol and skatol, while in others phenols are largely 

 formed. 



Aside from an increase in the degree of intestinal putrefaction, 

 larger amounts of the conjugate sulphates may also be observed if 

 putrefactive processes are taking place within the body proper, pro- 

 viding that active resorption occurs from the diseased area. An 

 increased elimination is also noted when any of the aromatic sub- 



