Exploration of the Species-specific Dna Markers Based on the Complete Chloroplast Genome for Discriminating Curcuma Comosa Roxb. From Curcuma Latifolia Roscoe and Other Related Species
Abstract Members of the Curcuma genus are among the most commonly used rhizomatous herbs worldwide. There are two species of Curcuma referred to as “Wan Chak Motluk” in Thai, C. comosa Roxb. and C. latifolia Roscoe, and their herbal materials are often confused. C. comosa is widely used as a traditional herbal remedy for its phytoestrogenic activity, but its morphology is highly similar to that of C. latifolia, which contains a compound that causes hepatotoxicity. In this study, the complete chloroplast (cp) genomes of these species were determined for the first time using Illumina sequencing. Our results showed that their cp genomes were 162,272 bp (C. comosa) and 162,289 bp (C. latifolia) in length. A total of 133 unique genes were identified, including 87 protein-coding genes, 38 tRNA genes and 8 rRNA genes. Comparative analyses with other species of Curcuma indicated high similarity in gene content and structural organization. The analyses also reveal variable hotspots in the genomes at ndhA, trnT-trnL, and ndhC-trnV that can serve as species-specific nucleotide barcodes. Indeed, mislabeling of these two species among samples sold at market was detected using these species-specific markers, indicating that cp genomes can provide more information for better elucidating and improving discriminatory power for species authentication.