Identification of Tibetan medicinal plants of Aconitum genus by ITS2 sequences / 中草药

ABSTRACT

Objective The complex morphological variation and sources of Tibetan medicinal plants from Aconitum genus make it difficult to identify the medicinal materials correctly. In addition, the toxicity of these materials could be a huge challenge for the safety of drug use. A rapid and accurate method for the identification and classification of Tibetan medicinal herbs of Aconitum genus was built by using ITS2 sequences as DNA barcodes. Methods A total of 50 samples of Aconitum chasmanthum, A. liangshanicum, A. kongboense, A. gymnandrum, A. pendulum, A. tanguticum, A. phyllostegium, A. campylorrhynchum, A. Polyschistum, and A. sessiliflorum were collected from the Qinghai-Tibet Plateau. PCR amplification and sequencing of ITS2 sequences were conducted after the extraction of DNA. Genetic distance, neighbor joining (NJ) phylogenetic tree and secondary structures of ITS2 sequences were analyzed using MEGA 6.0. Results The maximum distance between species was greater than the minimum distance within each species, NJ tree showed that the samples went to 12 separate branches, differences among the secondary structures of ITS2 sequences also made it clear to identify these species. Conclusion Using ITS2 sequence as DNA barcode can be an accurate and rapid method for identification and recognition for Tibetan medicinal plants of Aconitum genus, which provides a reliable technical means to ensure safety use of these Tibetan medicines.