Studies On Isolation, Modification And Bioactivities Of Protopanaxatriol Saponins In Leaves And Stems Of Panax Quinquefolium L

Panax quinquefolium L. which is in Araliaceae family, Panax genus originates from North America.The main active components in Panax quinquefolium L. are saponins. Saponins belong to triterpenes. Scholars from China and abroad have isolated and structure elucidated three kinds of saponin aglycons from Panax ginseng C. A. Meyer, Panax quinquefolium L. and Panax notoginseng(Burk.) F.H.Chen.They are Dammarane, Oleanane and Ocotillol. Dammarane saponins are in two kinds for having hydroxyl group or not on C-6: protopanaxadiol and protopanaxatriol.In this experiment, protopanaxatriol saponins in leaves and stems of Panax quinquefolium L. have been isolated.Using the AB-8 macroporous adsorptive resins to isolate saponins in leaves and stems of Panax quinquefolium L.,and get protopanaxatriol saponins. 9 kinds of protopanaxatriol saponins were separated and purified by column chromatography of silica gel, reversed phase silica column, semi-preparative high performance liquid chromatography and recrystallization methods. All of them were identified according to their physico-chemical properties and spectrum analysis(1HNMR,13CNMR,HMQC,HMBC). They are: notopanaxoside A (1), 20(S)- ginsenoside Rh1(2), 20(R)- protopanaxatriol(3), ginsenoside- Re(4), ginsenoside F5(5), 20(S)-ginsenoside Rg1(6), 20(S)-ginsenoside Rg2(7),20(E)- ginsenoside F4(8) and 20(S)- protopanaxatriol(9).Among them notopanaxoside A has been isolated from leaves and stems of Panax quinquefolium L. for the first time.With comlinatorial chemistry , psuedo–ginsenoside-F11 was transformed from 20(S)-ginsenoside- Rg2. The yield has been more than 80%, and the technological line is mature,and the approach is simple. The approach reaches the level of industrialized production. The bioactivity tests were carried out to investigate the effects of psuedo-ginsenoside F11 on rats with acut myocardial ischemia-induced by Pituitrin at different doses.Heart rate of model group decreased distinctively compared with blank control group ,P<0.05,P<0.01; Compared with model group, heart rate decrease which caused by pituitrin can be obviously improved in minimum dose group of psuedo-ginsenosideF11 ,P<0.05,P<0.01; Compared with model group,the percentage of heart rate decrease in minimum and medium dose groups can be obviously improved, P<0.05,P<0.01;Heart rate in the maximum dose group and nitroglycerol group can be improved,but not obviously.Since we intravenous injection pituitrin, rats are acute myocardial ischemia in 30 minute in model group,and J point and T wave in ECG are improved compared with blank control group ,P<0.05,P<0.01.The three dose groups of psuedo–ginsenosideF11 all have tendency of decrease J point,but not obviously, P>0.05.In nitroglycerol group J point of ECG decreases obviously compared with the one in model group, P<0.01.In maximum dose group can obviously decrease T wave elevation caused by the Myocardial ischemia,lower percentage compared with the model group P<0.05,P<0.01, In minimum and medium dose groups of PF11 and positive drug nitroglycerin group had lower T wave elevation in the trend, but compared with the model group, no significant difference, P>0.05.The results showed that PF11 can improve the decreased heart rate level which caused by pituitrin obviously. PF11 can also make T wave elevation in ECG decreases,and make the ECG of acute myocardial ischemia rats better.