Insights Into Phenolic Components of Gentianae Radix Et Rhizoma: Chemotaxonomic Markers Exploring Based on UPLC-Q-TOF-MS Profiling and HPLC Quantification Coupled With Chemometric Analysis, and Anti-Inflammatory Mechanism Digesting Using Network Pharmacology Analysis Approach.

Gentiana scabra Bge., Gentiana triflora Pall., Gentiana manshurica Kitag., and Gentiana rigescens Franch. were recorded as Gentianae Radix et Rhizome (Longdan) in Chinese Pharmacopoeia (ChP) and controlled by gentiopicroside (GPS). Owing to similar contents of GPS among these herbs, the demand for an effective method for Longdan classification and quality control remains urgent. In this study, we prepared the extract rich in phenolic components from four species herbs. UPLC-Q-TOF-MS analysis and bioactive evaluation revealed that Longdan phenolic extracts possess distinct phytochemical profiles and anti-inflammatory efficacy. After that, mangiferin, kaempferol, ferulic acid, and esculetin were selected as bioactivity-related components and potential quality markers for Longdan herbs. Subsequently, 16 batches of Longdan materials were quantitatively analyzed based on the contents of characteristic phenolic compounds. By means of chemometric analysis (circular heat map, principal component analysis [PCA], and hierarchical clustering), 16 batches of Longdan herbs could be well classified according to differences in phenolic index compounds (PICs). Furthermore, with the help of network pharmacology analysis, the underlying in vivo targets and gene pathways of PICs were illustrated. Thus, the systematic importance of Longdan phenolic components and usefulness of PICs for herbs differentiating were clarified and the established method is helpful for the quality control of Gentianae Radix et Rhizome.