Comprehensive metabolism study of polydatin in rat plasma and urine using ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry.

Polydatin is one of the main bioactive constituents isolated from Polygonum cuspidatum Sieb. et Zucc., which possesses various pharmacological activities. In this study, we established an efficient strategy based on ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry to uncover polydatin metabolites in rat urine and plasma. Firstly, multiple mass defect filters (MMDFs) combined with high-resolution extracted ion chromatograms (HREICs) was utilized to perform post-acquisition data-mining in ESI-MS1 stage. Secondly, metabolite candidates of polydatin were expounded systematically on the basis of diagnostic product ions (DPIs), chromatographic retention times, accurate mass, and neutral loss fragments (NLFs). Consequently, a total of 41 metabolites (polydatin included) were detected and identified tentatively in 12 min. These metabolites, including 40 in rat urine and 7 in rat plasma, were presumed to generate through glucuronidation, sulfation, deglucosylation, dehydrogenation, methylation, hydrogenation, hydroxylation and their composite reactions. Meanwhile, metabolite clusters, which were set in the form radially, were found in this study. In conclusion, our study expounded polydatin metabolites in rats and provided a reference for further researches on therapeutic material basis and mechanism of polydatin.

[Rapid characterization of chemical constituents in capillary wormwood extract based on UHPLC-LTQ-Orbitrap].

A rapid and sensitive UHPLC-HR-MSn method was developed for the identification of chemical constituents in capillary wormwood extract. ACQUITY UHPLC HSS T3 chromatography column (2.1 mm×100 mm, 1.7 µm) was used with 0.1% formic acid-acetonitrile solution as the mobile phase in gradient elution. The extract was detected by ESI-LTQ-Orbitrap equipped with an ESI ion source in a negative mode. Based on the accurate mass measurements, retention time, mass fragmentation patterns and literature reports, a total of 50 compounds including 21 flavonoids, 22 phenolic acids, 6 coumarins and 1 other compound were tentatively screened and characterized. These results are helpful for the comprehensive quality control, better comprehension of the metabolism and further study of pharmacodynamic substance from capillary wormwood extract.