On urobilin / by Archibald E. Garrod and F. Gowland Hopkins.

  • Archibald Garrod
Date:
[1896]
Catalogue details

Licence: Public Domain Mark

Credit: On urobilin / by Archibald E. Garrod and F. Gowland Hopkins. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    Spectrum of an Eichholz extract from a specimen of urine rich in uroro- sein and poor in urobilin Same more dilute Spectrum of extract from the urine of a typhlitis patient Spectrum of urorosein in alcohol-free chloroform Band of urorosein X 5700—5400 shading Band of urobilin X 5060—4860 A, ObiU—04UU shading \ 5060—4860 shading X 5080—4770 „ -— X 5825—5520 shading of green ] Band displaced to- wards red The physiological and pathological Urobilins ofJolles. In a recent paper Adolf J dies = gives his adhesion to the view that two distinct forms of urobilin occur in urine, a physiological and a pathological, which only agree in yielding the absorption band near F., and a green fluorescence with zinc chloride and ammonia. Like MacMunn Jolles regards the normal pigment as an oxidation product of bile pigment, and believes the pathological to be a reduction product, identical with Maly's hydrobilirubin. It may be noted that Jolles describes pathological urobilin as a red pigment, whereas we have found that when pure it acquires no red colour^even under the influence of mineral acids. In order to regard the physiological pigment of Jolles as a chemical individual it is necessary to assume that basic lead acetate precipitation exercises a highly selective action, throwing down the urobilin alone from normal urine, for the subsequent purification by alcohol cannot exert any such action; but, although the precipitation of the pigments by this salt is far less complete than when both acetates a?e used, we cannot look upon this proceeding as having any wch selective power. We believe that the ill-defined character of the urobilin band seen in extracts from normal urine, which Jolles, like MacMunn, regards as characteristic of normal urobilm, to be simply due to the fact that these brown extracts contain mere traces of urobilin, and owe their colour almost exclusively to other pigmentary substances carried down by the basic acetate of lead^ Jolles draws this further distinction between the two foims ot lOn dilution the mwosein J^and shrinks from the red end^^^ ^^^^^^^^^ . Eichhol. places the «f - ^^^^^^^^^^^^ his reading of the band -ly aUute the discrepancies to differences of scale. ^ Luc. cit.