Bilirubin Conjugate is a water soluble ditaurate derivative of bilirubin equivalent to bilirubin glucuronide derivatives¹.  Bilirubin glucuronide derivatives are produced in vivo from the glucuronidation (addition of one or two glucuronic acids through a glycosidic bond) of bilirubin (also called indirect bilirubin) in a reaction catalyzed by the enzyme UDP Glucuronidase.  The glucuronidation of bilirubin occurs in the liver to form the water soluble bilirubin mono or diglucuronide (also called bilirubin conjugate or direct bilirubin).  Bilirubin conjugate is excreted from the liver in bile or is converted to urobilinogen and excreted in the urine as urobilin or in the feces as stercobilin.