Panaxnotoginsengsaponins(PNS)arethemajorcomponentsofPanaxnotoginseng,withmultiplepharmacologicalactivitiesbutpoororalbioavailability.PNScouldbemetabolizedbygutmicrobiotainvitro,whiletheexactroleofgutmicrobiotaofPNSmetabolisminvivoremainspoorlyunderstood.Inthisstudy,pseudogerm-freeratmodelswereconstructedbyusingbroad-spectrumantibioticstovalidatethegutmicrobiota-mediatedtransformationofPNSinvivo.Moreover,ahighperformanceliquidchromatography-electrosprayionizationtandemmassspectrometry(HPLC-ESI-MS/MS)wasdevelopedforquantitativeanalysisoffourmetabolitesofPNS,includingginsenosideF1(GF1),ginsenosideRh2(GRh2),ginsenosidecompoundK(GCK)andprotopanaxatriol(PPT).Theresultsshowedthatthefourmetabolitescouldbedetectedinthecontrolratplasma,whiletheycouldnotbedeterminedinpseudogerm-freeratplasma.TheresultsimpliedthatPNScouldnotbebiotransformedeffectivelywhengutmicrobiotawasdisrupted.Inconclusion,gutmicrobiotaplaysanimportantroleinbiotransformationofPNSintometabolitesinvivo.
