748 UKINE. 



Uroerythrin is the pigment which often gives the beautiful red color to 

 the urinary sediments (sedimentum lateritium). It also frequently occurs 

 although only in very small quantities, dissolved in normal urines. The 

 quantity is increased after great muscular activity, after profuse perspira- 

 tion, immoderate eating, or partaking of alcoholic drinks, as well as after 

 digestive disturbances, fevers, circulatory disturbances of the liver, and 

 in many other pathological conditions. 



Uroerythrin, which has been especially studied by ZOJA, RIVA, and 

 GARROD, 1 has a pink color, is amorphous, and is very quickly destroyed 

 by light, especially when in solution. The best solvent is amyl alcohol; 

 acetic ether is not so good, and alcohol, chloroform, and water are even 

 less valuable. The very dilute solutions show a pink color; but on greater 

 concentration they become reddish orange or bright red. They do not 

 fluoresce either directly or after the addition of an ammoniacal solution 

 of zinc chloride; but they have a strong absorption, beginning in the 

 middle between D and E and extending to about F, and consisting of two 

 bands which are connected by a shadow between E and b. Concentrated 

 sulphuric acid colors a Uroerythrin solution a beautiful carmine red; 

 hydrochloric acid gives a pink color. Alkalies make its solution grass 

 green, and often a play of colors from pink to purple and blue is observed. 

 PORCHER and HERVIEUX 2 claim that Uroerythrin is a skatol pigment. 



In preparing Uroerythrin according to GARROD, the sediment is dissolved 

 in water at a gentle heat and saturated with ammonium chloride, which pre- 

 cipitates the pigment with the ammonium urate. This is purified by repeated 

 solution in water and precipitation with ammonium chloride until all the urobilin 

 is removed. The precipitate is finally extracted on the filter in the dark with 

 warm water, filtered, then diluted with water, any hsematoporphyrin remaining 

 being removed by shaking with chloroform; the precipitate is then faintly acidi- 

 fied with acetic acid and shaken with chloroform, which takes up the Uroerythrin. 

 The chloroform is evaporated in the dark at a gentle heat. 



Volatile fatty adds, such as formic acid, acetic acid, and perhaps also butyric 

 acid, occur under normal conditions in human urine (y. JAKSCH), also in that of 

 dogs and herbivora (SCHOTTEN). The acids poorest in carbon, such as formic 

 acid and acetic acid, are more stable in the body than those richer in carbon, 

 and therefore the relatively greater part of these pass unchanged into the urine 

 (SCHOTTEN). Normal human urine contains besides these bodies others which 

 yield acetic acid when oxidized by potassium dichromate and sulphuric acid 

 (v. JAKSCH). The quantity of volatile fatty acids in normal urine calculated as 

 acetic acid is, according to v. JAKSCH, 0.008-0.009 gram per twenty-four hours; 

 according to v. ROKITANSKY, 0.054 gram; and according to MAGNUS-LEVY 

 0.060 gram. The quantity is increased by exclusively farinaceous food (ROKI- 

 TANSKY), in fever and in certain diseases, while in others it is diminished (v. 

 JAKSCH, ROSENFELD). Large amounts of volatile fatty acids are produced in the 

 alkaline fermentation of the urine, and the quantity is 6-15 times as large as in 



1 Zoja, Arch. ital. di clinica med., 1893, and Centralbl. f. d. med. Wissensch., 1892; 

 Riva, Gaz. med. di Torino, Anno 43, cited from Maly's Jahresber., 24; Garrod, Journ. 

 of Physiol., 17 and 21. 



2 Journ. de Physiol., 7. 



