ABSTRACT
This chapter emphasizes studies which have concentrated upon the formation of ketone groups by oxidation of bile acid hydroxy groups. The major biliary bile acids in man are cholic acid (CA), chenodeoxycholic acid (CDCA), and deoxycholic acids (DCA). The conjugatedbile acids are released from the gall bladder by hormonal response to cholecystokinin (CCK). The entero-hepatic circulation (EHC) of bile acids in man is a system by which bile acids are recycled and conserved. Bile acids are synthesized and conjugated exclusively in the liver and excreted through the canaliculi into the biliary system. The discovery that bile salts are important in maintenance of a healthy colon led to an upsurge in studies related to bile acid physiology and bacterial metabolism. 7α-Dehydroxylation of the primary bile acids CA and CDCA to DCA and LCA respectively is a major bile acid transformation occurring in the human intestine.
