Identification of cimicifugae rhizoma and its adulterants using ITS2 sequence / 中国中药杂志

In order to identify Cimicifugae Rhizoma from its adulterants and to ensure its safe use, the internal transcribed spacer 2 (ITS2) sequence of Cimicifugae Rhizoma and its adulterants were amplified and bidirectionally sequenced by DNA barcoding technology. Sequence assembly and consensus sequence generation were performed by the CodonCode Aligner V3.7.1. The genetic distances were computed by MEGA 5.0. Identification analyses were performed using neighbor-joining (NJ) methods. The length of ITS2 sequence of the three origin plants of Cimicifugae Rhizoma include Cimicifuga heracleifolia, C. foetida, C. dahurica was 217, 219 and 219 bp, respectively. Their intraspecific genetic distance was much lower than the interspecific genetic distance with their closely related species. The NJ tree of ITS2 indicated that the three origin plants of Cimicifugae Rhizoma formed a monophyletic clade, Cimicifugae Rhizoma and its adulterants could be distinguished clearly. The authors proposed that ITS2 sequence was suitable for the authentication of Cimicifugae Rhizoma and its adulterants.

Identification of Bupleurum chinense and B. longiradiatum based on ITS2 barcode / 中国中药杂志

In this study, ITS2 barcode was used to identify Bupleurum chinense and B. longiradiatum. The ITS2 regions of 48 samples were amplified and sequenced. The sequences obtained above were aligned and the K2P distances were calculated. We used three methods, BLAST1, nearest distance and phylogenetic tree (NJ-tree), to test the identification ability. The results showed that the maximum intraspecific genetic distance of B. chinense was 0.013, and the minimum interspecific genetic distance between B. chinense and B. longiradiatum was 0.049. The NJ-tree can easily identify B. chinense and B. longiradiatum. Therefore, the ITS2 barcode is suitable to identify B. chinense and B. longiradiatum.