To study the biotransformation regulation and pharmacological effect of swertiamarin and its metabolite in incubated system of human intestinal flora.MethodsIncubated system of human intestinal flora was utilized to research the intestinal metabolism of swertiamarin. Furthermore, mutagenic test and anti-mutagenic test were carried out to research the activity relationship of swertiamarin and its metabolite.ResultsGentianine was found in the metabolites of swertiamarin. The pharmacological experiment indicated that swertiamarin and its metabolite both had good anti-mutagenic effect.ConclusionSwertiamarin is partly metabolized to gentianine after oral administration. They show similar anti-mutagenicity effects.