Studies On The Transformation And Elementary Cytotoxic Activities Of Protopanaxatriol Type Rare Pseudo-ginsenoside

Panax ginseng C.A.Meyer,a perennial plant belonging to the Araliaceae family,is widely used in medicine,nourishing and health care in east Asia and throughout the world.Recent studies have shown that it has anti-tumor efficiency and plays a significant role in anti-cardiovascular disease and improving immunity.Ginseng has many aspects of the tumor suppression activity and the role of immune regulation.because that contains a variety of reactive chemical composition,such as polyacetylene,saponins,peptides,polysaccharides,fatty acids,etc.,but its main active component is ginsenoside.Some PPT type ginsenosides has stronger anti-tumor activity which tending to increase as the number of sugar reduce,and ginsenoside side chain was modified PPT type pseudo-ginsenosides that has been reported has very good anti-tumor activity.However,these PPT type pseudo-ginsenoside are rare,which are difficult to obtain.The paper adopts ginsenoside Re that the low cost and high content as the raw material.The acetylation method was used to protect the hydroxyl groups,the acid catalyzed conversion method was used to modify the side chain,the alkali degradation and other methods were used to de-glycosyl.And the product of every step is purified by the positive and negative phase separation of the column chromatography.Finally,six rare side chain altered ginsenoside derivatives were obtained.Based on the analysis of the physical and chemical properties,IR,¹H-NMR,¹³C-NMR,HMQC,HMBC,1D-ROESY and HR-ESI-MS.Six compounds were identified:pseudo-ginsenoside Rg₂{3?,12?,25-trihydroxydammar-?E?-20?22?-ene-6-O-?-L-rhamnopyranosyl-?1?2?-?-D-glucopyranoside and 3?,12?,25-trihydroxydamma r-?Z?-20?22?-ene-6-O-?-L-rhamnopyranosyl-?1?2?-?-D-glucopyranoside}?pseudo-ginsenoside{3?,12?,25-trihydroxydammar-?E?-20?22?-ene-6-O-?-D-glucopyran oside and 3?,12?,25-trihydroxydammar-?Z?-20?22?-ene-6-O-?-D-glucopyranosi de}and pseudo-PPT{dammar-20?22?-ene-3,6,12,25-tetrol?3?,6?,12?,20E?and da mmar-20?22?-ene-3,6,12,25-tetrol?3?,6?,12?,20Z?}.In the step of alkali degradation,the degradation temperature,the alkali concentration and the degradation time were explored and studied by single factor and orthogonal test.Finally,the optimum degradation conditions were explored.Pseudo-ginsenoside Rh₁:at 235?,NaOH concentration is 8%,reaction 37 min,the maximum degradation rate is 21.8%.Pseudo-PPT:at 255?,NaOH concentration is12%,reaction 45 min,the maximum degradation rate is 29.8%.Cytotoxic activities showed:compound?has better inhibition in Caco-2?A549 than ginsenoside Rg₂,compound?has better inhibition in HepG2?MCF-7 than ginsenoside?,compound?has better inhibition in HepG2 than PPT.The study of preparation and activities provides a better direction for the research and development of the Pseudo-ginsenoside in the future.