Andrographis Echioides Molecular Characterization and Phylogenetic Study Using DNA Barcoding Technique

Abstract

With the advancement in various molecular diagnostic tools, DNA Barcoding has emerged as a gold standard molecular diagnostic tool across the globe. Since ancient times, medicinal plants have been widely used in Indian Ayurvedic medicine for treating a variety of ailments. Plants of the genus Andrographis have been extensively used for treating different types of ailments. In this study, rarely studied medicinal plant species were isolated, sequenced at the genetic level and studied for their evolutionary characteristics using phylogenetic analysis. In the present study, the identity of A. echioides was confirmed by targeting different barcoding genes such as ribulose-bisphosphate carboxylase, internal transcribed spacer, RNA polymerase-beta subunit, maturase K, and photosystem II protein D1 genes using a phylogenetic approach. After successful isolation and amplification of genomic DNA, specific primers were utilised for sequencing of each barcoding gene, followed by nucleotide BLAST analysis to determine the sequence percent identity of each gene with that from other plant species. The best homologs were then utilised for conducting phylogenetic analysis which confirmed the identity of the plant as Andrographis echioides.