A contribution to the study of the yellow colouring matter of the urine / by Archibald E. Garrod ; [communicated by Sir Alfred B. Garrod].

  • Garrod, Archibald Edward, 1857-1936.
Date:
[1894]
Catalogue details

Licence: Public Domain Mark

Credit: A contribution to the study of the yellow colouring matter of the urine / by Archibald E. Garrod ; [communicated by Sir Alfred B. Garrod]. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    tion of this substance the name “ Urochrome,” assigned to it by Thudichum, appears eminently suitable. The only points hitherto brought out which afford any clue to the chemical relationships of this pigment are the resemblance of the products of its decomposition to the humous substances described by Udranszky,* and the fact that it yields, when heated with nitric acid, a colour reaction which is indistinguishable from the xanthoproteic reaction, suggesting a relationship to the members of the aromatic series. Udranszky classes Thudiclium’s uromelanine and the other pro- ducts of the decomposition of urochrome as humous substances, and suggests as a possibility that the conversion of carbohydrates into such substances begins even within the body, and so may contribute to the yellow coloration of urine. Certainly uromelanine has, as might be expected, certain obvious resemblances to the products which TJdranszky obtained by the action of acids upon urine, and Thudichum long ago described how it might he prepared directly from urine by similar means. On the other hand, even if it he granted that the yellow pigment does yield humous substances on decomposition, any argument based upon this may well be regarded as open to the objection of explaining ignotum per ignotius. * £ Zeitschrift. f. Physiol. Chemie,’ vol. 11, 1887, p. 537, and vol. 12, 1888, p. 33. IIABEISON AND SONS, PEINTEES IN OlIDINAEY TO IIEE MAJESTY, ST. MABTIN’s LANE.