A yellow pigment formed when urobilinogen comes into contact with air.
Brown pigment found in feces and sometimes in small amounts in urine.
A brown pigment formed by the oxidation of urobilinogen, a decomposition product of bilirubin. Urobilin may be formed from the urobilinogen in stools or in urine after exposure to air.
A pigment derived from the decomposition of bilirubin, the red bile pigment, in the intestines, which is then eliminated through the kidneys into the urine, serving as the primary substance that imparts a yellow color to urine.