Identification of bile alcohols in human bile.

Abstract

Human gallbladder bile was examined for bile alcohols. Following isolation and hydrolysis, the bile alcohols were analyzed by capillary gas-liquid chromatography-mass spectrometry. The following bile alcohols were identified with certainty by direct comparison with reference standards: 5 beta-cholane-3 alpha,-7 alpha,23,24-tetrol; 5 beta-cholane-3 alpha,7 alpha,12 alpha,24-tetrol; 24-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol; 27-nor-5 beta-cholest-25-ene-3 alpha,7 alpha,-12 alpha,24-tetrol; 3 alpha,7 alpha,12 alpha-trihydroxy-27-nor-5 beta-cholestan-24-one; 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol; 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25,26-hexol; 5 beta-cholestane-3 alpha,7 alpha,24-triol; 5 beta-cholestane-3 alpha,7 alpha,25-triol; 5 beta-cholestane-3 alpha,7 alpha,26-triol; 5 alpha-cholestane-3 alpha,7 alpha,12 alpha,24-tetrol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24-tetrol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,26-tetrol; (24R)- and (24S)-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentols; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,26-pentol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,-25,26-pentol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,26,27-pentol; 26-methoxy-5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol. There also existed two norcholestanetetrols and three cholestanetetrols with two hydroxyl substituents on the nucleus and two in the side chain. The human biliary bile alcohols occurred mainly as sulfate esters and in lesser amounts as glucuronoconjugated and unconjugated forms. The amount of total bile alcohols was about 0.9 mg (0.7-1.2 mg) in 1 g of bile solid, or 0.16 mumol (0.07-0.24 mumol) in 1 ml of gallbladder bile.