Disposition and metabolism of the flavonoid chrysin in normal volunteers

Br J Clin Pharmacol. 2001 Feb;51(2):143-6. doi: 10.1111/j.1365-2125.2001.01317.x.


Aims: To describe the oral disposition of the dietary flavonoid chrysin in healthy volunteers.

Methods: Oral 400 mg doses of chrysin were administered to seven subjects. Chrysin and metabolites were assayed in plasma, urine and faeces by h.p.l.c.

Results: Peak plasma chrysin concentrations were only 3-16 ng ml(-1) with AUCs of 5-193 ng ml(-1) h. Plasma chrysin sulphate concentrations were 30-fold higher (AUC 450-4220 ng ml(-1) h). In urine, chrysin and chrysin glucuronide accounted for 0.2-3.1 mg and 2-26 mg, respectively. Most of the dose appeared in faeces as chrysin. Parallel experiments in rats showed high bile concentrations of chrysin conjugates.

Conclusions: These findings, together with previous data using Caco-2 cells, suggest that chrysin has low oral bioavailability, mainly due to extensive metabolism and efflux of metabolites back into the intestine for hydrolysis and faecal elimination.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Administration, Oral
  • Adult
  • Animals
  • Anti-HIV Agents / metabolism
  • Anti-HIV Agents / pharmacokinetics*
  • Flavonoids / metabolism
  • Flavonoids / pharmacokinetics*
  • Humans
  • Male
  • Models, Animal
  • Rats
  • Rats, Sprague-Dawley


  • Anti-HIV Agents
  • Flavonoids
  • chrysin