Identify the metabolites of total saponins of Platycodonis Radix in blood based on intestinal bacteria-mediated method

The identification of the components absorbed in serum of platycosides in total saponins fraction of Platycodonis Radix is great significance, but there are still great challenges. In this study, 8 types of 44 primordial components from Platycodon saponins were firstly identified using the ultra-performance liquid chromatography-linear ion trap electrostatic field orbitrap high resolution mass spectrometry (UPLC-LTQ-Orbitrap-MS) equipped with the software of Compound Discoverer 3.2 and Trace finder 2.1. Then, the platycosides and their deglycosylated metabolites were used as the template molecules to construct the intestinal microbiota mediated method to identify the primary components and the prototypes in serum. As results, 57 components originating from 44 prototypes of platycosides were identified from drug-containing plasma. Those compounds consist of 12 prototypes of platycosides and 45 metabolites, while the prototypes in serum are also deglycosylated metabolites of other platycosides. The results showed that the intestinal microbiota mediated method could be applied to identify the metabolites of platycosides in total saponins fraction of Platycodonis Radix; and reveal the potential existing forms of prototypes of platycosides in plasma; In addition, it could clearly illustrate the one to many and many to one network of the prototypes and metabolites of platycosides. All animal protocols were approved by the Animal Ethics Committee of Jiangxi University of Traditional Chinese Medicine (No.JZLLSC-202100322).