Deoxycholic acid-d4 (DCA-d4) is intended for use as an internal standard for the quantification of DCA (Item Nos. 20756 | 18231) by GC- or LC-MS. DCA is a secondary bile acid that is formed via microbial transformation of cholic acid in the colon. It can be conjugated to glycine or taurine to produce glycodeoxycholic acid (GDCA; ) or taurodeoxycholic acid (TDCA; ), respectively, in hepatocytes. DCA (0.2% v/v) inhibits spore germination induced by taurocholic acid (TCA; ) in seven C. difficile strains, as well as inhibits growth and decreases the cytotoxicity of C. difficile culture supernatants to Vero cells when used at a concentration of 0.02% v/v. It inhibits ionizing radiation-induced p53-dependent transcription in a reporter assay using HCT116 cells when used at a concentration of 200 μM. Fecal and intestinal tissue levels of DCA are increased in a rat model of high-fat diet-induced obesity compared with rats fed a normal diet. Increased serum DCA levels have been found in patients with colorectal cancer.
