An integrated approach to Q-marker discovery and quality assessment of edible Chrysanthemum flowers based on chromatogram–effect relationship and bioinformatics analyses

Medicinal Juhua (the flower head of five cultivars of Chrysanthemum morifolium Ramat.), Jinsi Huangju (the flower head of another cultivar), and Yajuhua (the flower head of Chrysanthemum indicum L.) are widely consumed as a traditional Chinese medicine and tea. Although they are similar in appearance, difference in the species or cultivation environment result in variations in their chemical constituents, pharmacological effects, and qualities. To assess the quality and authenticity of Chrysanthemum flowers, high-performance liquid chromatography (HPLC) and chemometrics were used to determine differential components. The components were identified by comparison with reference standards or by analysis of mass spectrometry and nuclear magnetic resonance data after HPLC-guided isolation. Then, the antioxidant, hepatoprotective, and angiotensin-converting enzyme (ACE) inhibitory activities of the samples and reference standards were studied, and chromatogram–effect relationship models were established to screen out the constituents significantly contributing to the bioactivities of the flowers. Subsequently, the quality markers (Q-markers) were determined based on their testability, characterization, and effectiveness. Finally, the Q-markers were investigated for potential antihypertension targets and pathways to further confirm their effectiveness using bioinformatics techniques, including network pharmacology and molecular docking. This developed integrated approach is robust and powerful for Q-marker discovery, quality assessment, and authentication of Chrysanthemum flowers and can also be extensively applied for the quality control of other herbal materials.