RESUMO
Objective:To characterize and compare the chemical information of four extracts of Qingre Chushi (QRCS) decoction by liquid chromatography-mass spectrometry (LC-MS), and combine the chemical information of the four extracts with their results of anti-inflammatory effect for a multivariate statistical analysis, in order to identify the compounds directly relating to the anti-inflammatory effects of QRCS decoction. Method:Four extracts of QRCS decoction were characterized by UPLC-Q-TOF-MS:①ethanol extract+water extract,② ethanol extract+supernatant after water extraction and alcohol precipitation, ③ ethanol extract+precipitation after water extraction and alcohol precipitation,and ④ standard decoction. On the basis of the results of inhibition of the four above extracts on xylene-induced ear swelling in mice,multivariate statistical analysis[principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA)] were carried out to lock the chromatographic peaks with significant differences between group ① (the best pharmacological action group) and group ④ (standard decoction group). According to the accuracy of quasi-molecular ion and fragment ion data,and the reference materials and literature data,those chromatographic peaks were identified. Result:PCA could cluster the four extracts of QRCS decoction,and the differences between groups was reflected in the distance between groups. Group ④ (standard decoction) had the most significant differences with the other three groups, especially in the first principal component; group ① (ethanol extract+water extract),group ② (ethanol extract+supernatant after water extraction and ethanol precipitation) and group ③ (ethanol extract+precipitation after water extraction and ethanol precipitation) had certain differences in the second principal component. OPLS-DA was used to compare group ① (the best pharmacological action group) and group ④ (standard decoction group). Eleven chromatographic peaks with great contribution and high reliability to group differences,were identified as gentiopicrin,skimmin,baicalin,baicalin isomer,wogonoside,5,6,7-trihydroxy-8-methoxyflavone-7-O-glucurodonaldehyde,5,6-dihydroxy-6,8,2',3'-tetramethoxyflavone,salicin-6-C-arabinose-8-C-glucoside,plantamajoside and glycyrrhizic acid. Conclusion:In the mode of pectrum-effect combination, this study explores and identifies compounds relating to the anti-inflammatory effect of QRCS decoction,so as to provide the basis for screening the extraction and purification process and optimizing the formulation of preparation of Qingre Chushi decoction.
