Dynamic stability-activity profiling of traditional Chinese medicine: Decoding functional substances through forced...

Traditional Chinese medicine (TCM) is a complex system with multiple components, and its effective ingredients are difficult to identify. This study aims to develop a dynamic stability-activity research strategy, taking Guizhi Fuling Capsules (GFC) as an example, to explore the stability of chemical components and decode functional substances through forced degradation experiments. GFC, a widely prescribed formula for gynecological blood stasis syndrome. Given the established association between dysmenorrhea pathogenesis and elevated cyclooxygenase-2 (COX-2) activity in endometrial cells, this study employed COX-2 enzyme inhibition as an in vitro bioassay to characterize the biological activity of GFC. Following the International Conference on Harmonization (ICH) guidelines, hydrolysis (acid, alkali, and neutral), oxidation (H₂O₂), thermal, and photolysis degradation tests were conducted. Significant degradation of major components, including total phenols, gallic acid derivatives, free fatty acids (linolenic/linoleic/oleic acid), paeonol, and cinnamaldehyde occurred under acidic, alkaline, oxidative, and thermal conditions. Crucially, Pearson correlation analysis revealed these components' stability positively correlated with preserved COX-2 inhibitory potency. Validation experiments further demonstrated that the total phenolic fraction and individual compounds (e.g., gallic acid) exhibited stronger COX-2 inhibition than intact GFC in vitro, suggesting total phenols, gallic acid, ethyl gallate, and 1,2,3,4,6-O-pentagalloyl glucose contribute significantly to GFC's bioactivity this study establishes a novel "stability-activity" assessment paradigm for traditional formulas and underscores the necessity of future in vivo investigations to elucidate integrated mechanisms within physiological contexts.