The Isolation Purification And Biological Activity Of Total Sapinons Hydrolysate From Gynostemma Pentaphyllum

Gynostemma pentaphyllum?Thunb.?Makino's dry whole grass is a perennial climbing herb.It is abundant in China and is mainly produced in the south of the Yangtze River and in Shanxi and Gansu.G.pentaphyllum is the mainly active ingredient of G.pentaphyllum and has a similar skeleton to ginseng saponin.It has many functions such as anti-oxidation,anti-tumor,blood sugar lowering,blood lipid regulation,liver protection,inhibition of obesity and improvement of immunity.In recent years,metabolic studies have shown that ginsenosides are finally metabolized in the body to produce secondary saponins and aglycons which are less polar,easy to absorb,and more biologically active.Therefore,in order to find aglycon which has higher activity and lower toxicity than saponin,the study systematically separated the acid hydrolysis product of G.pentaphyllum and evaluated its activity.The acid hydrolysis treatment is first carried out on the total saponins of G.pentaphyllum to obtain an acid hydrolysis product.Then,9 compounds were isolated by repeated silica gel column chromatography and recrystallization.Physicochemical properties,¹H-NMR,¹³C-NMR and other NMR spectroscopy methods and databases were combined with HR-ESI-MS to identify their structures:gypensapogenin A?1?,20?S?-ginseng Glycol?2?,gypensapogenin F?3?,?-spinol sterol?4?,?23S?-3?-hydroxydama-20,24-diene-21-carboxylic acid 21,23-lactone?5?,gypsapogenin A?6?,?20S,24S?-3?,20,21?,23?,25-pentahydroxy-21,24-epoxydammarane?7?,20?R?-protopanaxadiol?8?and?-sitosterol?9?.The effects of 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-?2,4,6-trinitrophenyl?hydrazyl radical scavenging capacity?DPPH?,2,2'-Azinobis-?3-ethylbenzthiazoline-6-sulphonate?radical scavenging capacity?ABTS+·?and Superoxide Radical Scavenging ability?PSC?were used to evaluate Antioxidant activity of total saponins and acid hydrolysates of G.pentaphyllum and its monomeric compounds.Experiments show that the test samples have certain antioxidant capacity,but their antioxidant capacity is significantly weaker than that of the positive control vitamin C?Vc?.The?-glucosidase inhibitor screening method and protein tyrosine phosphatase?PTP1B?inhibitor screening method were used to determine the inhibitory effect of each compound on?-glucosidase and protein tyrosine phosphatase?PTP1B?to stdy hypoglycemic activity.The results showed that each compound had?-glucosidase inhibitory activity,and the inhibition rate and dose were in a certain dependence.Compound 1 and 5 have the highest activity and are in a concentration-dependent manner.The IC₅₀values were 10.73?M and2.50?M,respectively,which was higher than that of the positive control drug acarbose.Each compound had protein tyrosine phosphatase?PTP1B?inhibitory activity,and the inhibition rate was positively correlated with the dose.The best inhibition rate of the hypoglycemic activity of Compound 1 and 5 was 10.77?M and 8.84?M,respectively,which was higher than that of the positive control drug vanadate.The Lineweaver-Burk plot was used to determine that the inhibition type of?-glucosidase of Compound 1 and 5 was competitive inhibition,and the inhibition type of PTP1B was also competitive inhibition.The spatial combination mode of the compound and PTP1B was investigated by molecular docking.It can be seen from the overall figure that the compound binds to the protein.It can be seen from the 2D diagram that the amino acid residues of compound 5 and PTP1B are respectively:Tyr-46?Cys-215?Phe-182?Lys-120?Val-49?Ile-219?Met-258.However,from the partial three-dimensional diagram,compound 5 is not completely combined with the active pocket.Studies on synthetic or isolation to fully fill the PTP1B active pocket to increase the activity of the compound to promote its hypoglycemic effect are meaningful.This experiment demonstrates that the compounds isolated from the total saponin hydrolysate of G.pentaphyllum play a potential role in blood sugar lowering,in order to find a newer and more active lead compound,thus becoming a function of preventing and treating metabolic diseases such as diabetes and obesity.The development of factors into health care products provides an important theoretical basis.