Analysis of Terpenoids in Alismatis Rhizoma Before and After Processing with Salt-water Based on UPLC-Q-TOF-MS / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo identify the chemical constituents of Alismatis Rhizoma before and after processing with salt-water by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry （UPLC-Q-TOF-MS）， and to investigate the changes of terpenoids in Alismatis Rhizoma before and after processing with salt-water. MethodUPLC-Q-TOF-MS was used to detect with 0.1% formic acid aqueous solution （A）-acetonitrile （B）as mobile phase for gradient elution （0-0.01 min， 20%B； 0.01-5 min， 20%-40%B； 5-40 min， 40%-95%B； 40-42 min， 95%B； 42-42.1 min， 95%-20%B； 42.1-45 min， 20%B）， electrospray ionization （ESI） was selected for collection and detection in positive ion mode with the scanning range of m/z 100-1 250 and ion source temperature at 500 ℃. The data were analyzed by PeakView 1.2.0.3， the components were identified according to the primary and secondary MS data， and combined with the reference substance and literature. After normalized treatment by MarkerView 1.2.1， the MS data were analyzed by principal component analysis （PCA） and orthogonal partial least squares-discriminant analysis （OPLS-DA）， and then the differential components before and after processing were screened. The content changes of differential components were analyzed according to the relative peak area. ResultA total of 30 components were identified under positive ion mode， including 28 prototerpene triterpenes and 2 sesquiterpenes. The results of PCA and OPLS-DA showed that there were significant differences in components from Alismatis Rhizoma before and after processing with salt-water， and 10 differential components （alisol B 23-acetate， alisol I， alismol， 11-deoxy-alisol B 23-acetate， alisol B， alisol C， 11-deoxy-alisol B， alisol G， 11-deoxy-alisol C and alisol A） were screened， and the contents of alisol G and alisol A decreased significantly after processing. ConclusionUPLC-Q-TOF-MS can comprehensively and accurately identify the chemical constituents in raw and salt-processed products of Alismatis Rhizoma. It takes a great difference in the contents of chemical constituents before and after processing， and the difference of substituents is the main reason for this differences， which can provide reference for determining the material basis of efficacy changes of Alismatis Rhizoma before and after processing with salt-water.