[Measurement of total bile acids. Comparison of different preparations of 3 alpha-hydroxysteroid dehydrogenase]

Oxidation of free and conjugated biliary acids was carried out with 5 different enzymatic preparations of 3 alpha-hydroxysteroid dehydrogenase. The comparison of the catalytic activities obtained, shows the existence of important variations according to the enzymes. Preparations purified by chromatography have a stronger activity toward primary biliary acids than toward secondary biliary acids, while preparations obtained from bacterial mutants have a low activity toward cholic acid and its conjugates.