Using DNA Barcoding to Detect Adulteration in Different Herbal Plant- Based Products in the United Arab Emirates: Proof of Concept and Validation

Background: Commercially available herbal and medicinal plants-based products are susceptible to substitution or contamination with other unlabeled or undesired materials. This will reduce the quality of the product, and may lead to intoxication and allergy. Methods: DNA barcoding is a molecular technology that allows the identification of plant materials at the species level, by sequencing short stretches of standardized gene sequences from nuclear or organelle genome in an easy, rapid, accurate and cost-effective manner. The aim of this research is to apply DNA barcoding to investigate the authenticity of commercially available herbal and medicinal plant-based products within the UAE markets. A total of 30 samples were analyzed, covering six different herbal products (thyme, cardamom, anise, basil, turmeric, and ginger), obtained in fresh and dried forms. DNA was extracted and three barcode loci including (rbcL), (matK) and (ITS) were amplified, sequenced and analyzed by BLAST. Results: In terms of amplification efficiency, the results suggest that rbcL is the most suitable marker for species identification giving 75% of successful amplification, followed by ITS with 66.67%, whereas matK had the lowest with 18.52%. Adulteration was detected in two samples, ginger powder and dry thyme leave samples. The adulterants were from Triticum and Oryza genera. Conclusion: Clearly, the results from this report provide evidence that DNA barcoding technique is efficient in the recognition of commercial plant products. Thus, it can be considered as a fast, effective, and reliable method to detect adulteration in plant-based products in the UAE market.