Using ITS2 barcode to identify Ephedrae Herba

Abstract

To identify Ephedrae Herba using the ITS2 barcode and to secure its quality and safety in medication. Total genomic DNA was isolated from Ephedrae Herba and its closely related species. Nuclear DNA ITS2 sequences were amplified, and purified PCR products were sequenced. Sequence assembly and consensus sequence generation were performed using the CodonCode Aligner. The Kimura 2-Parameter (K2P) distances were calculated using software MEGA 5.0. Identification analyses were performed using BLAST1, Nearest Distance and neighbor-joining (NJ) methods. The intra-specific genetic distances of Ephedrae Herba were ranged from 0 to 0.002. The inter-specific genetic distances between Ephedrae Herba and its closely related species were ranged from 0.004 to 0.034. All the three methods showed that ITS2 could discriminate Ephedrae Herba from its closely related species correctly. The ITS2 region is suitable to be used for authentication of Ephedrae Herba, and our study further confirmed the effectiveness of ITS2 to identify traditional Chinese medicinal materials.