Molecular Identification And Phylogenetic Analysis Of Coleus Amboinicus (Lour.) A.J.Paton And Plectranthus Barbatus (Andrews) Through DNA Barcoding: Deciphering Genetic Relationships

Abstract

Coleus amboinicus and Plectranthus barbatus, belonging to the Lamiaceae family. They are closely related phylogenetically. These plants have high medicinal values for respiratory and gastrointestinal diseases. Proper utilization of these plants requires accurate identification of species. But traditional identification based on morphological characteristics is often misleading due to the phenotypic plasticity of similar species. This study focuses on the development of a rapid DNA barcoding approach to distinguish between C. amboinicus and P. barbatus, DNA from both species was used, and the rbcL gene, ITS region, and spacer psbA-trnH were amplified and sequenced. The sequences were then compared using the BLASTn program against the GenBank database. Developed the DNA barcodes. This uniquely structured ITS2 secondary structure had been predicted; its unique features effectively distinguish species that are highly related, like C. amboinicus and P. barbatus, which also enhance species identification and phylogenetic resolution. Phylogenetic analysis showed that C. amboinicus and P. barbatus belong to different clades that have distinct genetic divergence. The results demonstrate the efficacy of DNA barcoding in distinguishing between these species and highlight its potential for promoting the sustainable utilization of these medicinal plants.