In silico identification for flavor antioxidant compounds in Chrysanthemi flos uncovers the interactions between saccharides and secondary metabolites.

Secondary metabolites and saccharides are responsible for antioxidant activity and flavor of Chrysanthemi flos (CF). However, the flavor antioxidant compounds of CF and their intermolecular interactions remain unclear. Here, we primarily employed in silico methods to identify CF antioxidants. After characterizing by physicochemical properties, FT-NIR and HPLC fingerprint, the "spectrum-effect" fusion correlation was established to select the spectral features of CF antioxidants. Quercetagitrin (QU), chlorogenic acid (CA) and saccharides fragments were clarified based on their characteristic spectrum. The antioxidant efficacy as well as the sweet and bitter taste of these compounds were verified by molecular docking. Quantum chemical calculations demonstrated that non-covalent interactions dominant facilitated the stable existence of CF antioxidants. The most significant binding types between CA, QU and saccharides fragments were hydrogen bonding. These results indicate a novel approach and theoretical support to discovery of new information pertinent to the bioactive compounds related to CF or other tea.