ABSTRACT
ObjectiveTo explore the material basis of bile-processed Coptidis Rhizoma clearing excessive fire of liver-gallbladder based on ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF/MS） metabolomics and molecular docking. MethodUPLC-Q-TOF/MS metabolomics was used to analyze the chemical constituents of Coptidis Rhizoma， water-processed Coptidis Rhizoma and bile-processed Coptidis Rhizoma. Chromatographic separation was achieved with 0.1% formic acid aqueous solution（A）-acetonitrile（B） as the mobile phase in gradient elution（0-2 min， 5%B； 2-20 min， 5%-65%B； 20-40 min， 65%-10%B； 40-45 min， 10%B； 45-46 min， 10%-95%B； 46-49 min， 95%B）， and electrospray ionization（ESI） was applied and operated in positive and negative ion modes， the acquisition range was m/z 80-1 200. Based on this， partial least squares-discriminant analysis（PLS-DA） and variance analysis were used to screen the differential compounds among the three products of Coptidis Rhizoma. Network pharmacology and molecular docking were used to verify the degree of association between differential compounds and excessive fire of liver-gallbladder syndrome. ResultA total of 33 chemical constituents were identified， including 2 phenolic acids， 5 binding bile acids and 26 alkaloids. And 16 differential compounds were identified by multivariate statistical analysis， including 11 alkaloids and 5 binding bile acids. Pathway enrichment analysis in the Kyoto Encyclopedia of Genes and Genomes（KEGG） database yielded 8 pathways related to excessive fire of liver-gallbladder， and the key protein phosphatidylinositol 4，5-bisphosphate 3-kinase catalytic subunit alpha isoform（PIK3CA） was obtained according to the "component-target-pathway" network analysis. Molecular docking results showed that 11 alkaloids had good binding ability with PIK3CA. ConclusionPorcine bile is unique in the processing of bile-processed Coptidis Rhizoma， which can promote the production and dissolution of 11 alkaloids， including berberine and dihydrochelerythrine. Based on the results of molecular docking and reported pharmacological experiments， it can be concluded that 16 different compounds such as berberine， dihydrochelerythrine and taurohyodeoxycholic acid are the material basis of bile-processed Coptidis Rhizoma.