Studies On Triterpenoids And Cytotoxic Activity Of Gypsophila Oldhamiana Miq.

Gypsophila oldhamiana Miq., known as “Xia Cao” in Chinese, belongs to the Caryophyllaceae family. It is widely distributed in the north regions of China, such as northeast, northwest, north of China. G. oldhamiana Miq. is an especially rich source of triterpenoid saponins. Its roots have been used as a traditional Chinese Medicine to treat fever,consumptive, infantile malnutrition and so on.Objective: To study triterpenoid constituentsof G. oldhamiana Miq., biotransformation of total saponins in G. oldhamiana Miq., and their cytotoxic activity.Methods: The best extraction process of total saponins in G. oldhamiana Miq. was optimized by orthogonal experiment. Triterpenoid constituents of G. oldhamiana Miq.,biotransformation of total saponins in G. oldhamiana Miq. were isolated and purified by silica gel column chromatography, Sephadex LH-20, G-25 column chromatography,ODS column chromatography and preparative HPLC chromatography and recrystallizat ion methods. Their structures were determined on the basis of physicochemical propert-ies and spectroscopic data. The cytotoxic activity of the isolated compounds against human tumour cell lines(lung cancer H460 and gastric cancer SGC-7901) were tested by MTT method.Results: G. oldhamiana Miq. extracted with ethanol extracted was concentrated to a suitable volume, put it aside at room temperature, then the precipitation was recrystallized with ethanol. The total saponins in G. oldhamiana Miq. was obtained by this method. Ten compounds were isolated and elucidated from the Et OAc and n-Bu OH fraction of the methanol extract of the air-dried roots of G. oldhamiana Miq.Their structures were identified to be 3?-hydroxyolean-13(18)-en-23, 28-dioic acid(I),3?, 12?-dihydroxy-23-carboxyolean-28, 13?-olide(II), 3?, 16?-dihydroxy-23-carboxyolea n-13(18)-en-28-oic acid(III), gypsogenin(IV), quillaic acid(V), gypsogenic acid(VI),oleanolic acid(VII), collinsogenin(VIII), oldhamianoside I(IX), quillaic acid 3-O-?-Dglucoside(X). Four biotransformation of total saponins in G. oldhamiana Miq. were modified to be quillaic acid(V), oldhamianoside I(IX), quillaic acid ?-D-fucopyranosyl ester(XI), quillaic acid ?-L-rhamnopyranosyl-(1?2)-?-D-fucopyranosyl ester(XII).Compounds I-VI were evaluated for their cytotoxic activities against human tumour cell lines(lung cancer H460 and gastric cancer SGC-7901) by MTT method. The results showed that compounds I-VI have strong cytotoxic activity.Conclusion: Twelve triterpenoid constituents were isolated from the Et OAc and n-BuOH fraction of the methanol extract of the air-dried roots of G. oldhamiana Miq. and biotransformation of total saponins in G. oldhamiana Miq.. Among them, compound I and II were new compounds, and compounds I-VI showed the significant cytotoxicities against H460 and SGC-7901.