Study On The Self-assembly Characteristics And Structures-activities Of Bidesmosidic Triterpenoid Saponins From Kalopanax Septemlobus

Natural products have attracted the attention of supramolecular chemistry researchers because of their many advantages such as wide sources,abundant contents and diverse structures.However,so far,the number of natural small molecules with self-assembly characteristics has been found to be still small;Meanwhile,the research on the relationship between molecular structure and assembly characteristics lags far behind biological applications and pharmacological studies.Therefore,it is of great significance to discover natural small molecules with self-assembly characteristics,and further study their mechanism of action and structure-activity relationships,which can be applied to biomedical,drug delivery,and other life sciences.In this paper,the self-assembly characteristics and structure-activity relationships of bisdesmosides from Kalopanax septemlobus are systematically explored in depth with the following four parts:The first part,the extraction and separation of chemical components from the saponins of Kalopanax septemlobus.Four compounds were obtained by extracting with 75%ethanol,extracting with ethyl acetate and n-butanol,concentrating,and separating by silica gel column chromatography,Sephadex LH-20 column chromatography,reversed phase C-18 column chromatography,and semi-preparative HPLC.The second part,the structural identification of the chemical components of the saponins from Kalopanax septemlobus.The compounds were identified by nuclear magnetic resonance techniques(¹H NMR,¹³C NMR,DEPT,HSQC,¹H-¹H COSY,HMBC,TOCSY,and NOESY)as the active components of kalopanaxaponin A,kalopanaxaponin B,kalopanaxaponin H,and septemlosideⅠ.The third part,the self-assembly characteristics of bisdesmosides from Kalopanax septemlobus.Nuclear magnetic resonance spectroscopy,scanning electron microscopy,transmission electron microscopy,and molecular dynamics simulation techniques were used to investigate its spatial structure and mechanism of action.In terms of spatial structure,the NOESY spectrum shows that the rhamnose methyl hydrogen of the C-3 glycan of the bidesmosidic saponin,the rhamnose methyl hydrogen of the C-28 glycan,and the double bond hydrogen and the C-23 hydroxyl hydrogen in the aglycone have correlation peaks with each other,while the rhamnose methyl hydrogen of the C-3 glycan and the terminal hydrogen of arabinose have correlation peaks,indicating that they are close to each other in space;At the same time,the results of scanning electron microscopy,transmission electron microscopy,and molecular dynamics simulation showed that the bidesmosidic triterpenoid saponins displayed a lumpy and twisted state as a whole.In terms of mechanism,it mainly functions from both internal and external factors,including molecular structure,hydrogen bonds,and other forces;External factors include concentration and solvent.One of the necessary conditions for the formation of the above self-assembly behavior is the presence of two glycans and a certain number of sugar groups within the molecule.The fourth part,the structures and activities relationship of the self-assembly of bisdesmosides from Kalopanax septemlobus.Using network pharmacology technology to collect action targets,screen potential therapeutic targets for inflammation,screen core targets,and analyze the enrichment of GO and KEGG pathways in the study of compounds containing selenium side I to explore the mechanism of their anti-inflammatory activity.Molecular docking techniques were used to investigate the binding force of T and S conformations to core target proteins corresponding to HSP90AA1 and TLR4 genes,respectively,in order to conduct structure-activity relationship studies.In this paper,the phenomenon,mechanism of action,and structure-activity relationship of the self-assembly of natural product bidesmosidic kalopanaxsaponins have been deeply explored.It is hoped that the above research can provide new ideas for the regulation and preparation of the self-assembly process of natural product triterpenoid saponins,thereby better exerting the advantages of good compatibility and biological activity of natural products.