Nuclear ribosomal DNA – ITS region based molecular marker to distinguish Gmelina arborea Roxb. Ex Sm. from its substitutes and adulterants

Roots of Gmelina arborea (Gambhari) is a medicinally important raw drug traded in India. However, Gmelinaasiatica and Mallotus nudiflorus are also found in the raw drug markets as Gambhari. The current study aims to identify molecular markers based on the nuclear ribosomal DNA – ITS1 region to distinguish the authentic species from substitute/adulterants. The nuclear ribosomal internal transcribed spacer 1 (ITS1) was amplified to identify species-specific markers using universal primers. Based on the sequence of the ITS region, specific primers were designed for G. arborea, G. asiatica and M. nudiflorus which efficiently amplified 142 bp, 93 bp and 150 bp of the ITS1 region of the respective species. The notable feature of this molecular method is that it is technically accurate, practically convenient and suitable for analyzing large numbers of samples. This study demonstrates that the ITS1 region can be used for reliable authentication of medicinal plants and detection of adulterants and substitutes of Gambhari.