Studies on Bile Pigments VIII. A Form of Direct Reacting Bilirubins Appearing in Jaundiced Urine

Separation of the urinary ester-form bilirubin was attempted, and the results obtained may be summarized as follows: 1. A brown pigment was obtained from jaundiced urine by the following procedures; namely, salting out, methanol extraction, chloroform flocculation, and separation on cellulose column. The pigment has been found to be easily soluble in water, displaying the absorption maximum at 420 - 410 mμ at pH 7.0, and it also gave a positive reaction both to GMELIN's and EHRLICH's diazo reagents within a minute without the addition of alcohol. These characteristics agree well with those of the socalled ester-form bilirubin. 2. On the basis of the results of paper chromatography and paper electrophoresis, the pigment has been determined to contain no amino acid, steroid, nor reducing substance. Moreover, no glucuronic acid could be detected whether examined in vitro or by paper chromatography together with paper electrophoresis, either.