Thermodynamics driving phytochemical self-assembly morphological change and efficacy enhancement originated from single and co-decoction of traditional chinese medicine

Through the self-assembled strategy to improve the clinical efficacy of the existing drugs is the focus of current research. Herbal formula granule is a kind of modern dosage form of traditional Chinese medicine (TCM) which has sprung up in recent decades. However, whether it is equivalent to the TCM decoction that has been used for thousands of years has always been a controversial issue. In this paper, taking the herb pair of Coptidis Rhizoma-Scutellariae Radix and its main component berberine-baicalin as examples, the differences and mechanisms of self-assemblies originated from the co-decoction and physical mixture were studied, respectively. Moreover, the relationship between the morphology and antibacterial effects of self-assemblies was illuminated via multi-technology. Our study revealed that the physical mixture's morphology of both the herb pair and the phytochemicals was nanofibers (NFs), while their co-decoction's morphology was nanospheres (NPs). We also found that the antibacterial activity was enhanced with the change of self-assemblies' morphology after the driving by thermal energy. This might be attributed to that NPs could influence amino acid biosynthesis and metabolism in bacteria. Current study provides a basis that co-decoction maybe beneficial to enhance activity and reasonable use of herbal formula granule in clinic.