Comprehensive chemical profiling of Pinellia species tuber and processed Pinellia tuber by gas chromatography–mass spectrometry and liquid chromatography–atmospheric pressure chemical ionization–tandem mass spectrometry

A comprehensive profiling method was established for the determination of various chemicals in Pinellia (P.) ternata and pedatisecta species. The profiling method comprises a fast ultrasonic extraction with various solvents, followed by GC–MS and LC–APCI-MS analysis. A total of 73 polar components as trimethylsilyl (TMS) derivatives were detected in methanol extract by GC–MS. The main components of the P. species were profiled as several kinds of fatty acids, amino acids, nucleic acids, carbohydrates, and phenolic compounds. The hexane extract was analyzed by LC–APCI-MS for the lipid profiling. A total of 35 lipid constituents [fatty acids and their esters, mono-, di-, and tri-acylglycerols] and four phytosterols were observed and tentatively characterized by LC–APCI-MS/MS. Among the phytochemicals detected in the hexane extract, triacylglycerols (TAGs) as the major component were identified by LC–APCI-MS and MS/MS. Based on the identified components, a significant difference in the chemical compositions of P. species tuber and processed P. ternata was found that the complete disappearance of TAGs and a considerable decrement of sucrose were observed in processed P. ternata. Furthermore, the degradation mechanism for TAGs in the presence of alum solution is suggested to occur during the processing P. ternata. Malic acid was found to be a characteristic compound for the classification of P. ternata and pedatisecta with different geographic origins. Based on the validated GC/MS method, twenty-four P. ternata, processed P. ternata and P. pedatisecta samples were profiled to measure the overall abundance of specific groups of compound and to identify diagnostic compounds. In addition, principal component analysis (PCA) on the GC/MS profiling data revealed a clear classification of P. species samples. In this study, the full chemical complement was for the first time reported for quality evaluation of P. species. The method can be usefully applied for phytochemical analysis of related herbal medicines.