cholate

The spermicides benzalkonium chloride and sodium cholate are used in some contraceptive sponges.

The final concentrations of sodium cholate and sodium deoxycholate were 1.3mM and 3.4mM, respectively.

Fifty microlitres of [1 4 C]-sodium cholate was added as an internal standard to allow assessment of recovery rates at the end of the extraction procedure.

After extracting 3x more with the same cholate solution, the pooled supernatants were diluted 10x with buffer A and centrifuged at 180,000 g for 45 min to collect the membrane pellet.

Inhibition of gram-positive bacteria is achieved by the incorporation of ox gall, which is a naturally occurring substance containing a mixture of bile salts, and sodium cholate, a pure bile salt.

Supernatants were diluted 200-fold with buffer A containing no EDTA and 18.5mM sodium cholate and assayed for PLC activity as described, except that EGTA (3mM) was used as a chelating agent.

The proportion of metabolites of chenodeoxycholic acid and cholate was however higher in the cancer group, as reflected by lower ratios of chenodeoxycholic acid and cholate to their total derivatives (Table IV).

The concentration for the bile salt treatment was selected to mimic the concentration of bile salts in MacConkey Agar (1.5 g/L of Sigma Bile Salts, consisting of 50% sodium cholate, 50% sodium deoxycholate), which is typically used to identify enteric bacteria.