Headspace Solid-Phase Micro-Extraction Gas Chromatography/Mass Spectrometry (HS-SPME-GC/MS)-Based Untargeted Metabolomics Analysis for Comparing the Volatile Components from 12 Panax Herbal Medicines

Abstract

Quality control of ginseng currently is mainly based on ginsenoside analysis, but rarely focuses on the volatile organic components. In the current work, an untargeted metabolomics approach, by headspace solid-phase micro-extraction gas chromatography/mass spectrometry (HS-SPME-GC/MS), was elaborated and further employed to holistically compare the compositional difference of the volatile components simultaneously from 12 Panax herbal medicines, which included P. ginseng (PG), P. quinquefolius (PQ), P. notoginseng (PN), red ginseng (PGR), P. ginseng leaf (PGL), P. quinquefolius leaf (PQL), P. notoginseng leaf (PNL), P. ginseng flower (PGF), P. quinquefolius flower (PQF), P. notoginseng flower (PNF), P. japonicus (PJ), and P. japonicus var. major (PJvm). Chromatographic separation was performed on an HP-5MS elastic quartz capillary column using helium as the carrier gas, enabling good resolution within 1 h. We were able to characterize totally 259 volatile compounds, including 82 terpenes (T), 46 alcohols (Alc), 29 ketones (K), 25 aldehydes (Ald), 21 esters (E), and the others. By analyzing 90 batches of ginseng samples based on the untargeted metabolomics workflows, 236 differential ions were unveiled, and accordingly 36 differential volatile components were discovered. It is the first report that simultaneously compares the compositional difference of volatile components among 12 Panax herbal medicines, and useful information is provided for the quality control of ginseng aside from the well-known ginsenosides.