Molecular Pharmacognosy on Tibetan Traditional Medicine Dong-Na Duan-Chi / 中国中医药信息杂志

Objective To identify the common Tibetan herb Dong-Na Duan-Chi by molecular pharmacognosy. Methods Ethnopharmacology investigation was carried out and local herbalists were visited to observe which plants were being used as Dong-Na Duan-Chi. Then, nuclear ribosomal DNA ITS sequences were amplified and sequenced for molecular identification. Results The botanic origins of Dong-Na Duan-Chi in Tibet Autonomous Region were authenticated as two species, i.e. Veronica eriogyne H.Winkl. and Veronica ciliata Fisch.. The sequences of ITS for Veronica eriogyne and Veronica ciliata are 551 bp and 552 bp in size. The results showed that nrDNA ITS sequences could be used to discriminate V.eriogyne and V.ciliata from closely related species. Conclusion nrDNA ITS sequences can be used as the molecular markers to identify the Tibetan herb Dong-Na Duan-Chi from other species of the same genus Veronica L.

Determination of genetic variation in Rhodiola crenulata from the Hengduan Mountains Region, China using inter-simple sequence repeats

The plant Rhodiola crenulata is a perennial herbaceous species distributed in the plateau region of southwestern China, especially the Hengduan Mountains region. It has been one of the most important traditional herbal remedies in Tibet for more than one thousand years, but the accelerated and uncontrolled collection of this plant since the 1980s has lead to deforestation. We used inter-simple sequence repeats (ISSR) to assess levels of genetic variation in R. crenulata from nine diverse natural populations in eastern Tibet and northern Yunnan, the first time such a study has been carried out. The 12 primers we used were able to detect 184 polymorphic loc. Analysis of molecular variance (AMOVA) indicated that species level genetic diversity was relatively high (p = 97.83 percent, and Ho = 0.464) and analysis using ShannonÆs index showed that the within and between genetic diversity of R. crenulata are approximately equal. NeiÆs genetic distance and unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis showed that the three populations from Tibet and the six populations from Yunnan form two major clusters. The Yunnan populations from three locations were further divided into three corresponding groups, indicating that genetic differentiation was correlated to geographic distribution. Understanding the genetic structure of R. crenulata provides insight for the conservation and management of this endangered species.