Abstract
Objective: Sakurasosaponin, a primary bioactive saponin from Aegiceras corniculatum, shows potential as an anti-cancer agent. However, there is a lack of information on its in vivo metabolism. This study aims to profile the in vivo metabolites of sakurasosaponin in rat feces, urine, and plasma after oral administration. An efficient strategy using ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry was developed, which combined metabolic prediction, multiple mass defects filtering, and highresolution extracted ion chromatograms for rapid and systematic analysis.
Methods: Firstly, a theoretical list of metabolites for sakurasosaponin was developed. This was done by considering the metabolic pathways of saponins. Next, the multiple mass defects filtering method was employed to identify potential metabolites in feces and urine, using the unique metabolites of sakurasosaponin as multiple mass defects filtering templates. Subsequently, a high-resolution extracted ion chromatogram was used to quickly determine the metabolites in rat plasma post-identification in feces and urine. Lastly, the analysis of accurate mass, typical neutral loss, and diagnostic ion of the candidate metabolites was carried out to confirm their structural elucidation, and metabolic pathways of sakurasosaponin in vivo were also proposed. Results: In total, 30 metabolites were provisionally identified in feces, urine, and plasma. Analysis of metabolic pathways revealed isomerization, deglycosylation, oxidation, hydroxylation, sulfate conjugation, glucuronide conjugation, and other related reactions as the primary biotransformation reactions of sakurasosaponin in vivo. Conclusion: The findings demonstrate that the designed research strategy effectively minimizes matrix interference, prevents the omission of low-concentration metabolites, and serves as a foundation for the discovery of active metabolites of sakurasosaponin.