[Effect of decoction method on phase state and biological activity of Cinnamomi Cortex-Coptidis Rhizoma...

Based on supramolecular chemistry of TCM, this study investigated the interaction between Cinnamomi Cortex-Coptidis Rhizoma herb pair and compared phase states and bioactivity differences under different decoction methods(co-decoction vs individual decoction followed by mechanical mixing). Phase state variations were observed macroscopically and through turbidimetry. The herb interaction was analyzed using isothermal titration calorimetry, UV and IR spectroscopy. Particle size differences were determined by dynamic light scattering and scanning electron microscopy(SEM). Antimicrobial activity was evaluated through broth dilution, plate coating, live/dead staining, and SEM. Component analysis was conducted using UPLC-MS/MS. RESULTS:: revealed distinct supramolecular structures in Cinnamomi Cortex-Coptidis Rhizoma decoctions, with co-decoction showing more stable macroscopic phase states. The interaction was a spontaneous exothermic reaction driven by both entropy and enthalpy. UV and IR spectra revealed co-decoction demonstrated more sufficient molecular interactions, more stable supramolecular structures, and smaller particle sizes with a more centralized distribution. In addition, co-decoction resulted in higher berberine and coptisine content and stronger inhibitory activity against Staphylococcus aureus compared to mechanical mixtures. These findings indicated that co-decoction produced Cinnamomi Cortex-Coptidis Rhizoma supramolecular systems with more homogeneous phase states, enhanced measurable coptisine and berberine content, and superior antibacterial efficacy.