Isolation and identification of key bitter substances in Chrysanthemum morifolium (Chuju) and their interaction mechanism with bitter taste receptors based on HPLC-Q-TOF-MS and molecular docking

Abstract Chrysanthemum morifolium（Chuju）, a plant with both medicinal and edible value, faces limitations in its widespread utilization in food and medicine due to its bitter taste. This study aimed to isolate the key components contributing to the bitterness in Chuju by solvent extraction, silica gel column chromatography, and High-performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry (HPLC-Q-TOF-MS) guided by sensory evaluation, sensory evaluation combines artificial sensory evaluation and electronic tongue evaluation. And use the Dose-Over-Threshold (DoT) factors to evaluate the relative contribution of these bitter compounds. Finally selected three bitter compounds of the high contribution to bitterness, respectively Vitexin, Orientin and Kaempferol. The DoT factor in the artificial sensory evaluation is 8.77, 2,73 and 0.40. In the electronic tongue, the DoT factor is 136.62, 1.51 and 26.88. Subsequently, using molecular docking to verify the combination of bitter compounds and bitterness receptors between TAS2R14, and get the mechanism of interaction between molecules. Ultimately, the docking scores of the three bitter compounds are all greater than -5, demonstrating their tight binding to the bitterness receptor. Therefore, this study identified the key bitter substances in Chuju and could provide a reference for the wide application and bitter reduction of Chuju in the future.