Study On The Terpene Glycosides In Raw Materials Of Ginkgo Biloba Injection

The Ginkgo biloba L.is the only extant gymnosperm of Ginkgoaceae Ginkgo and has important medicinal value.In the 1960s,a standardized extract of Ginkgo biloba leaves（GBE）was developed and named EGb 761,and since then,the production of GBE has continued to expand.Ginkgo biloba injection is one of the formulations of GBE that is widely used in the clinical treatment of cerebrovascular and peripheral vascular disorders.However,despite the quality control requirements of containing 24.0%total flavonol glycosides and 6.0%terpene lactones,a large portion of the unknown components still exist in Ginkgo biloba injection.Therefore,thoroughly elucidating its material basis and corresponding biological activity is of great significance.This study selected Ginkgo biloba injection raw materials as the research object and used various modern chromatographic separation and purification techniques,including silica gel column,MCI column,Sephadex LH-20,RP-C18 and HPLC,to isolate and purify a large number of monomeric compounds.Then,various modern spectroscopic analysis and identification methods,such as HR-ESI-MS,1D and 2D NMR,X-ray single-crystal diffraction,Mosher’s method,computational ECD,were used to systematically and comprehensively analyze the structures of these isolated monomeric compounds.Finally,a total of 41 monomeric compounds were identified,including one artificially synthesized product.The classified compounds isolated from Ginkgo biloba injection raw materials include 12 terpene glycosides,10 lignans,10 flavonoids,and 9 other compounds.Among them,there are 8 new compounds,including 4 megastigmane glycosides,1 bilobanone glycoside and its hydrolysis product,and 2 phenylbutenoids.All four megastigmane glycosides are ionol（ionone）type compounds,and one of them,the ionone type megastigmane glycoside（YX-1）,is a new skeleton compound,with the side chain of ionone forming a new five-membered ring.The absolute configuration of the two phenylbutenoids and bilobanone glycoside hydrolysis product was determined by X-ray single-crystal diffraction,and the absolute configuration of the remaining megastigmane glycosides and bilobanone glycoside was finally determined by consulting literature,Mosher’s method,comparing their calculated ECD and experimental ECD data,and other methods.To detect the potential biological activity of all new compounds,it was found through literature review that megastigmane glycosides may have cytotoxic effects on tumor cells.Therefore,all newly isolated compounds were subjected to cytotoxicity evaluation on experimental cells,including human liver cancer cells Hep-3B,human colon cancer cells HCT-116,human breast cancer cells MCF-7,and non-cancerous human umbilical vein endothelial cells（h UVEC）.The results showed that all new compounds had no significant cytotoxic effects on all experimental cells(IC₅₀>100μM).According to the experimental results,it is known that these newly discovered compounds do not have significant biological activity against tumor cells and are not toxic to humans.This study enriched the material basis of Ginkgo biloba injection,preliminarily studied the partial biological activity and toxicity of new compounds,and played a positive role in elucidating the material structural basis of Ginkgo biloba injection.