URINE 



457 



95 per cent alcohol, and 5 c.c. of concentrated hydrochloric acid. Raise the 

 temperature gradually to the boiling-point and boil for one minute, shaking the 

 tube continuously. Stand the tube aside four minutes, then cool under the 

 tap. Extract with an equal volume of ether. Glycuronates are indicated by 

 the ether extract assuming a violet-red color. The spectroscope shows this 

 extract to possess two absorption bands, one on the D line and one to the right 

 of this line. 



2. Polariscopic-Fermentation Test. If glucose is present in the urine tested 

 for glycuronates the urine may first be subjected to a polariscopic examination, 

 then fermented and a second polariscopic examination made. The sugar being 

 dextrorotatory and fermentable and the glycuronates being levorotatory and 

 non-fermentable the second polariscopic test will show a levorotation indicative 

 of conjugate glycuronates. 



3. Reduction-Polariscopic Test. Test the urine by Fehling's test. If 

 positive try the Resorcinol-HCl reaction for fructose. If negative test the optical 

 activity. Levorotation indicates glycuronates. 



PENTOSES 



We have two distinct types of pentosuria, i.e., alimentary pentosuria, 

 resulting from the ingestion of large quantities of pentose-rich fruits 



FIG. 136. PENTOSAZONE CRYSTALS. 



Isolated and purified in the author's laboratory by Mr. B. L. Fleming. From the urine 

 of a patient in the service of Dr. S. Solis Cohen, Jefferson Hospital, Phila. For color of 

 crystals see Plate III, opposite page 22. 



such as prunes, cherries, grapes, or plums, and fruit juices, in which 

 condition the pentoses appear only temporarily in the urine; and the 

 chronic form of pentosuria, in which the output of pentoses bears no 



