Genetic Diversity And Biological Activity Study Of Panax Japonicus C. A. Mey

Panax japonicas C. A. Mey,a member of the important perennial herb in Araliaceae family,its wild P. japonicas resources are approaching endangered,artificial cultivation of P. japonicas research is becoming systematic and scaly,the genetic diversity study of germplasm resources has great significant.Our team based on the study of transcriptome sequencing,continue to analysis the genetic diversity of P. japonicas using ISSR markers,study the antioxidant activity of total saponins in vitro of P. japonicas,chikusetsusaponin V repair on PC-12 cell line injured by Aβ25-35, explore expression level of chikusetsusaponin V influences on gene APLP-1 and gene ADAM-17.Research results are as follow:1、 18 primers which can produced clear,stable and polymorphism bands from 30 primers,36 alleles have been detected,the average number of ISSR loci alleles(Na) was 2,effective number of alleles(Ne) was 1.1623,Shannon’s information index(I) was 0.2330;Nei’s genetic diversity index(h) was 0.1262.Mean of diversity index within populations(Hs) was 0.1008,Coefficient of population differentiation(Gst) was 0.2116,gene flow(Nm) among population was 1.9750,polymorphism information content(PIC) was 0.26.2、 In the dendrogram generated by UPGMA analysis of the ISSR data,P. japonicas from 12 areas were clustered into two main groups.The first group made up of Sichuan,Hubei,Hunan and Yunnan,they have closer relationship with similarity coefficient 0.796-0.803;Guangxi and Guizhou was another group.Similarity coefficient among different P. japonicas populations ranged from 0.79 to 0.88. Principal component analysis(PCA) and clustering results are basically identical.3、 PC-12 cell line,which was damaged by Aβ25-35,w as selected as the model.Results show that Chikusetsusaponin V could gradually protect cell line against the cytotoxicity of Aβ25-35,p roliferation is higher at 12、24 h time point(p<0.05),at 18 h time point, the proliferation get the highest(p<0.01).The expression level of APLP-1 gene in model groups is obviously higher than in control groups,ADAM-17 gene is obviously lower than the control groups,and APLP-1 gene in PC-12 cell line treatment with chikusetsusaponin V is strikingly down-regulated, ADAM-17 gene is up-regulated.4、 DPPH and ABTS method were used to evaluate the antioxidant activity of total chikusetsμsaponin. Five monomer compositions of chikusetsusaponin Ⅳa,chikusetsusaponin Ⅳ,ginseng saponin Ro,ginseng saponin Rb1,ginseng saponin Rg1 were determined by HPLC method,correlation analysis was made between the five monomer content and the concentration of DPPH and ABTS.Results show that the total saponins of P. japonicas has good antioxidant activity,Guangxi Guilin has the best antioxidant activity,Guizhou Yushe is the last,Hubei Enshi ranks the second,Sichuan E’mei ranks the third.Correlation analysis indicates that chikusetsusaponin Ⅳ content has significant positive correlation with the concentration of DPPH and ABTS(p<0.01),chikusetsusaponin Ⅳa content has significant negative correlation with the concentration of DPPH(p<0.05),and negative correlation with ABTS(p<0.01).Research results in our team laid the foundation work for P. japonicas genetic diversity and pharmacological activity researches.