A review on molecular techniques employed for authentication of Indian medicinal plants

Traditional medical systems are advancing to the level of modern medicines in treatment and preventive aspects. The increased trade in medicinal plants provides income source for herbalists while substitution of rare ingredients with cheaper and more readily available species is misleading the end users. The prime cause of the problems associated with the standardization of medicinal plants is complex composition of herbal drugs used in the form of whole plants, plant parts or extracts. Deliberate adulteration of intended ingredients are posing difficulty in distinguishing the genuine resources. Authentication of medicinal plants by recent molecular techniques is inevitable for herbal drug industries, researchers and academia. Of late, herbal genomics, molecular studies of medicinal plants and powerful next generation sequencing techniques have been emerged to transform the current knowledge. A compilation of various molecular markers used, their efficiency in barcoding for the purpose of accurate authentication of herbal drugs has been attempted in this study. Data were collected from previous literature and online repositories like NCBI, Pubmed etc. There are various molecular techniques that can be exploited for authentication of medicinal plants such as Restriction Fragment Length Polymorphism (RFLP), Random Amplified Polymorphic DNA (RAPD), Amplified Fragment Length Polymorphism (AFLP), Sequence Characterized Amplified Region (SCAR), Selective Amplification of Microsatellite polymorphic loci (SAMPL), Simple Sequence Repeats (SSR), Inter Simple Sequence Repeat (ISSR), DNA barcoding, Next Generation Sequencing Techniques etc. Some of medicinal plants were reported having molecular data useful in plant identification. The genomic data of poly herbal formulations helps for scientific validation and universal recognition. Even though the challenges associated with reprehensibility, primer designing, amplification products of molecular markers and troubles related with DNA isolation and purification, become the major obstacle in front of researchers. It is high time to focus these novel strategies for proper identification to ensure the fidelity of traditional herbal products and there by promoting a step towards the global acceptance of our indigenous medicinal systems