Chemical differentiation of Da-Cheng-Qi decoction and its three analogous decoctions using UFLC-IT-TOF/MS-based chemomic and chemometric approach

Abstract

A rapid, sensitive and efficient ultrafast liquid chromatography (UFLC)-ion trap time-of-flight mass spectrometry (IT-TOF/MS) coupled with multivariate statistical analysis method has been developed and validated for evaluating chemical differentiation of Da-Cheng-Qi Decoction (DCQD) and its three analogous decoctions. DCQD, Xiao-Cheng-Qi Decoction (XCQD), Hou-Pu-San-Wu Decoction (HPSWD) and Hou-Pu-Da-Huang Decoction (HPDHD), four similar prescriptions of traditional Chinese medicines (TCMs) widely used in the treatment of gastrointestinal diseases, were decocted according to literature and then subjected to UFLC-MS analysis. The data matrix integrating of retention time (t_R), mass-to-charge ratio (m/z) pairs, ion intensities and sample codes were processed with principal components analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The results indicate significant differences existing among these four decoctions and twenty-six chemical markers were screened out, of which five were from the root and bark of Radix et Rhizoma Rhei, eight from the bark of Magnolia officinalis Rehd and the rest from Fructus Aurantii Immaturus after identification by retention time and MS data. The underlying relationship between the difference in quantity of chemical markers and the difference in pharmacological effect of four similar decoctions is discussed. The LC/MS method combined with chemomic and chemometric approach provided a global research direction of chemical differentiation of DCQD and its three analogous decoctions and laid a foundation for the subsequent comparative pharmacological study of the four decoctions in vivo.