ABSTRACT
Xiaoer-Feire-Kechuan (XFK) is an 11-herb Chinese medicine formula to treat cough and pulmonary inflammation.The complicated composition rendered its chemical analysis and effective-component elucidation.In this study,we combined quantitative analysis and bioactivity test to reveal the anti-inflammatory constituents of XFK.First,UPLC-DAD and UHPLC/Q-Orbitrap-MS methods were estab-lished and validated to quantify 35 analytes (covering 9 out of 11 herbs) in different XFK formulations.Parallel reaction monitoring mode built in Q-Orbitrap-MS was used to improve the sensitivity and selectivity.Then,anti-inflammatory activities of the 35 analytes were analyzed using in vitro COX-2 inhibition assay.Finally,major analytes forsythosides H,I,A (8-10),and baicalin (15) (total contents varied from 21.79 to 91.20 mg/dose in different formulations) with significant activities (inhibitory rate ≥ 80％) were proposed as the anti-inflammatory constituents of XFK.The present study provided an effective strategy to discover effective constituents of multi-herb formulas.
ABSTRACT
Steady improvement in mass spectrometers technology has transformed the targeted proteome analysis into a new stage. Parallel reaction monitoring (PRM) technology has evolved from the basic multiple reaction monitoring (MRM) targeted proteomics methods in recent years. PRM performs with a higher sensitivity, throughput and reproducibility in targeted quantification, however its limitations in effectiveness and accurate quantification of samples with higher complexity still remain unsolved. In this study through improving the chromatographic conditions of PRM we established a simple and robust platform for targeted proteomic quantification. The newly established PRM system is equipped with columns with increased inner diameter (150 μm) and decreased total length (8 cm); faster liquid phase elution rate (800 nL/min) and shortened elution gradient (35 min). These modifications enable PRM platform to combine with dual reverse phase chromatography, to quantify up to 400 low abundance peptides in human 293T cells whole cell extract. Our findings would benefit the promotion of PRM technology, especially providing a technical option for accurate quantification of low abundance proteins.