Applying DNA barcoding technique to identify Menthae Haplocalycis Herba

Abstract

To identify Menthae Haplocalycis Herba and its closely related species using DNA barcoding technique. Total genomic DNA was isolated from Mentha canadensis 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 V3.0. 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 M. canadensis were ranged from 0 to 0.006, which were lower than inter-specific genetic distances between M. canadensis and its closely related species (0.071-0.231). All the three methods showed that ITS2 could discriminate M. canadensis from its closely related species correctly. The ITS2 region is an efficient barcode for identification of Menthae Haplocalycis Herba, which provides a scientific basis for fast and accurate identification of the herb.