Geographic Variation In Gene-based Molecular Components Of Rhubarb Efficacy Study MatK Formed Phylogeography Evidence

Rhei Radix and Rhizoma is a typical deputation of multi-function and multi-component Chinese Medicine, it have been widely used due to its wide range of pharmacological and clinical effects. However, precisely because of its characteristics of multi-functional and multi-component, the effect of Rhei Radix and Rhizoma was sometimes unstable. The reason for the phenomenon may be caused by the active ingredients in Rhei, because the contents of active ingredients in Rhei were different among different locations. In order to improve the stable effects of Rhei in clinical, it was important to analyze the phenomenon of geographic variation of effective component.If we want to get a clear idea of the geographic variation of effective component in Rhei, we must find out the reason of geographic variation, and show the pattern of geographic variation, and understand the application of geographic variation.In addition, recent years’excessive consumption has resulted in the imminent danger of Rhei. At the same time, the reproductive rate of Rhei is very low. Its growth is sensitive to ecological conditions, and the seed propagation is not easy to succeed. The wild resource of Rhei is becoming endangered. To protect the resources of Rhei, we should investicate the genetic diversity while the geographic variation was invesitcated.In summary, it is necessary to investicate the geographic variation of effective components in Rhein and to analyze the reason of geographic variation. Our study will be helpful in clinical medication.We have investigated the geographic variation of effecitive components in Rhei, and provided a genetic proof based on the molecular Phylogeography methods. The main results of our research were as follows:1We established the method for simultaneous dtermination of14active constituents contents in rhubarb by HPLC. We analyzed the contents of5free anthraquinone compounds,5anthraquinone glycosides, the gallic acid and catechin compounds and2anthrone glycoside compounds.2The one-way AMOVA analysis showed that14active ingredients and3effective components have a significant difference between the places of regions. The average contents of4active ingredients and3effective components of each location also showed a significant difference, which indicated the geographic variation.According to the Cluster and PCA results, the average components analysis of different locations of R. palmatum and R. tanguticum, the contents and proportion of different locations were differed greatly. We can divide the locations as different types on the basis of the effective components. We analyzed three factors which may affecte the geographic pattern of R. palmatum and R. tanguticum, the three factors were longitude, latitude and altitude. The results showed that, in R. palmatum, the free anthraquinone, the combined anthraquinone, the gallic acid and catechin may affected by longitude, latitude and altitude, but there was no positive significant between the three effective components and the three factors. The sennoside A and B was affected mainly by the latitude. In R. tanguticum, the free anthraquinone may affected by longitude, latitude and altitude, but there was no positive significant between the free anthraquinone and the three factors. The combined anthraquinone was affected mainly by the altitude. The sennoside A and B, the gallic acid and catechin were affected mainly by the longitude.3According to the results of molecular Phylogeography analysis, there were9haplotypes in R. palmatum and15haplotypes in R. tanguticum. The distribution of these haplotypes differed a lot. The genetic diversity analysis showed a relatively high genetic diversity in species level, and the genetic diversity among populations was higher than within populations. Furthermore, the Nst value was higher than Gst value, which indicated a significant geographical structure.The NCA analysis demonstrated that there were many factors for rhubarb’geographical structure, such as restricted gene flow with isolation by distance, allopatric fragmentation, past fragmenatation, continuous range expansion, and so on.4Compared with the geographical variation of effective components and the molecular phylogeography pattern, and then there was a significant relationship between them. The quaternary glacial period and the lifted Qinghai-Tibet Plateau caused a enormous environmental change, this may result to the change of genetic material, and thereby leading to the geographic variation of effective components.5According to our research results, there was a generally geograpgic variation of effective components in rhubarb, it will be helpful to the breeding of rhubarb. Additionally, the genetic diversity among populations of rhubarb was low, and we should pay our attention to the protection of rhubarb.In this study, we have analyzed the pattern of geographic variation of effective components and molecular phylogeographi in rhubarb, and then discussed their relationship. This work can provide a basis for genetic resource conservation and cultivated suggestions of rhubarb.