Chemical fingerprinting and multivariate analysis of Paeonia ostii leaves based on HPLC-DAD and UPLC-ESI-Q/TOF-MS/MS

Paeonia suffruticosa Andr. (Tree peony) is a well-known traditional Chinese medicine, which has been widely cultivated for thousands of years and its root bark is used in many prescriptions. Oil peony (Paeonia ostii and Paeonia rockii) has been planted in large areas since tree peony seed oil was approved as a new food resource by the National Health Commission (Ministry of Health) of P.R. China in 2011. However, tree peony leaves were often regarded as waste resources during cultivation and there were few comparative studies on the chemical constituents of tree peony leaves from different origins. In this study, thirty-five P. ostii leaves from four provinces in China were taken as the research objects. The methods of high-performance liquid chromatography (HPLC-DAD) fingerprinting combined with multivariate analysis, including similarity analysis (SA), principal component analysis (PCA), orthogonal partial least square method-discriminant analysis (OPLS-DA) and hierarchical cluster analysis (HCA), were used to evaluate the difference of chemical composition between thirty-five samples. UPLC-ESI-Q/TOF-MS/MS and HPLC-DAD were used for qualitative and quantitative analysis of characteristic components. The results showed that seventeen common characteristic peaks were screened from HPLC fingerprints and the similarity of thirty-five samples was between 0.864 and 0.999. Thirty-five samples from different origin were divided into four groups by OPLS-DA and PCA, but not HCA. Meanwhile, ten compounds were found to be the most closely related marker components for quality evaluation. In addition, 56 characteristic chemical components were preliminarily identified from P. ostii leaves by UPLC-ESI-Q/TOF-MS/MS technology. Finally, the quantitative analysis results showed that there were some differences in the chemical contents of seven characteristic components in thirty-five P. ostii leaves. This study provided a reasonable method for the discrimination and quality evaluation of P. ostii leaves from different producing areas, and laid a foundation for the comprehensive utilization and development of P. ostii resources.