Identification of cyprinol and cyprinol sulfate from grass carp bile and their toxic effects in rats.

To elucidate the responsible toxic components of grass carp bile, the bile salt 5 alpha-cyprinol sulfate and its desalted form 5 alpha-cyprinol from grass carp bile were purified and identified by analyses of infrared spectrum, (1)H-, (13)C-nuclear magnetic resonance spectra and mass spectrum. The toxicity of grass carp bile powder, butanol extract of grass carp bile powder, 5 alpha-cyprinol and 5 alpha-cyprinol sulfate in rats were further determined. The kidney and liver functions were significantly affected by grass carp bile powder, butanol extract and 5 alpha-cyprinol sulfate. However, 5 alpha-cyprinol also significantly affected the kidney function, but the toxic effect was less.