Measurement of faecal bile acid sulphates

A method is described for the measurement, by difference, of the sulphate fractions of faecal bile acids. A solvolysis step (for the deliberate hydrolysis of the bile acid sulphates) was added to the procedure of sample homogenisation, extraction, enzymatic hydrolysis and thin-layer chromatography. The bile acids were quantitated by gas—liquid chromatography of their methyl ester and trifluoroacetate methyl ester derivatives on 3% QF-1 columns. The total bile acid excretion in 15 control subjects was 603 ± 71 mg/24 h (x̄ ± S.E.M.). The major bile acid peaks (mg/24 h) were: lithocholic acid, without solvolysis 118 ± 26 and including solvolysis 175 ± 30; deoxycholic acid 60 ± 8 and 90 ± 18 and chenodeoxycholic acid 13 ± 7 and 15 ± 7. It was concluded that bile acid sulphates may form a considerable proportion of the total bile acids excreted in man.