Simultaneous Qualitative and Quantitative Study of Main Compounds in Commelina communis Linn. by UHPLC-Q-TOF-MS-MS and HPLC-ESI-MS-MS.
This study reported the identification and determination of the main components of Commelina communis Linn. A total of 62 compounds were identified in C. communis Linn. extract, which included 29 flavonoids and flavonoid glycosides, 17 phenolic acids, 4 alkaloids, 1 pyrimidine alkaloids, 3 sterols and 8 fatty acids and others by ultra high performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry. Moreover, a specific, simple, rapid and sensitive high performance liquid chromatography with tandem mass spectrometry method was developed and validated for determination of 13 components of C. communis Linn., which included orientin, iso-orientin, vitexin, isovitexin, rutin, apigenin, protocatechuate, vanillic acid, caffeic acid, ferulic acid, luteolin, quercetin and isorhamnetin. All calibration curves showed good linearity (r ≥ 0.9991) within the test range. The intra- and inter-day precisions (relative standard deviation%, RSD%) were within 1.04 and 0.92%, and the recoveries ranged from 98.64 to 100.8%. These results may contribute to the further study and quality control for C. communis Linn.
Identification of metabolites of oridonin in rats with a single run on UPLC-Triple-TOF-MS/MS system based on multiple mass defect filter data acquisition and multiple data processing techniques.
Oridonin (ORI) is an active natural ent-kaurane diterpenoid ingredient originating from well-known traditional Chinese herb medicine and is expected to be pursued as a new anticancer agent. In the present study, a novel and efficient approach was developed for in vivo screening and identification of ORI metabolites using ultra high performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry (UPLC-Triple-TOF-MS/MS). This analytical strategy was as follows: an effective on-line data acquisition method multiple mass defect filter (MMDF) combined with dynamic background subtraction (DBS), was developed to trace all of potential metabolites of ORI. The MMDF and DBS method could trigger an information dependent acquisition scan, which could give the information of low-level metabolites masked by background noise and endogenous components in complex matrix. Moreover, the sensitive and specific multiple data-mining techniques including extracted ion chromatography, mass defect filtering, product ion filtering and neutral loss filtering were employed to identify the metabolites of ORI. Then, structures for the metabolites were successfully assigned based on accurate masses, the mass fragmentation of ORI and metabolic knowledge. Finally, an important parameter Clog P was used to estimate the retention time of isomers. Based on the proposed strategy, 16 phase I and 2 phase II metabolites were detected in rats after oral administration of ORI. The main biotransformation route of ORI was identified as reduction, oxidation, dehydroxylation and glucuronic acid conjugation. This is the first study of ORI metabolism in vivo. This study not only proposed a practical strategy for rapidly screening and identifying metabolites, but also provided useful information for further study of the pharmacology and mechanism of ORI in vivo. At the same time this methodology can be widely applied for the structural characterization of the metabolites of other ent-kaurane diterpenoid.
Metabolite profiles of icariin in rat plasma by ultra-fast liquid chromatography coupled to triple-quadrupole/time-of-flight mass spectrometry.
In this work, the metabolite profiles of icariin in rat plasma were qualitatively investigated, and the possible metabolic pathways of icariin were subsequently proposed. After oral administration of icariin, rat plasma samples were collected and pretreated by protein precipitation. Then these pretreated samples were injected into a Venusil ASB-C18 column with mobile phase consisted of 0.1% formic acid water and 0.1% formic acid acetonitrile and detected by Ultra fast liquid chromatography coupled to time-of-flight mass spectrometry (UFLC-TOF/MS). A total of 19 metabolites, namely, icariside I (M1), icaritin (M2), desmethylicaritin and its isomer (M3-M6), icaritin-3-O-gluA (M7), icaritin-7-O-gluA (M8), icariside II and its isomer (M9 and M10), icaritin-3,7-di-O-gluA (M11), 1,3-isoprene alcohol icaritin and its isomer (M12, M13 and M18), 1,3-isoprene alcohol icariside II (M14), allylic alcohol icaritin and its isomer (M15 and M16), 1,3-isoprene icariside II (M17) and icaritin-3-O-rha-7-O-gluA (M19) were detected and tentatively identified, and 9 of them, including M7 and M8 and M12-M18 were reported for the first time. The metabolites profiles in plasma revealed that glucuronide conjugates of isoflavonoids and flavonoid aglycones were the major circulating forms of icariin.