DNA-Based Herbal Teas' Authentication: An ITS2 and psbA-trnH Multi-Marker DNA Metabarcoding Approach

Area of Science:

• Botany
• Genetics
• Food Science

Background:

• Medicinal plants are increasingly used in food supplements, but face significant fraud and adulteration challenges.
• Traditional identification methods are insufficient for verifying the complex composition of these products.

Purpose of the Study:

• To evaluate DNA metabarcoding as a reliable tool for identifying the composition of medicinal plant products.
• To assess the efficacy of two DNA barcode regions (psbA-trnH and ITS2) for species identification.
• To explore the potential of high-throughput sequencing (HTS) for quantitative analysis of plant ingredients.

Main Methods:

• DNA metabarcoding analysis of fifteen commercial medicinal plant products.
• Utilized two distinct DNA barcode regions: psbA-trnH and ITS2.
• Created and analyzed mock mixtures of known plant materials (biomass and gDNA) to assess quantitative accuracy.

Main Results:

• An average of 70% of declared ingredients were identified across the analyzed products.
• The ITS2 marker identified more species (60) than psbA-trnH (35), with higher identification rates (52% vs. 45%).
• DNA metabarcoding demonstrated potential for relative quantitative analysis of plant components.

Conclusions:

• DNA metabarcoding is a powerful tool for identifying medicinal plant ingredients and combating adulteration in food supplements.
• The ITS2 marker shows greater efficacy for species detection compared to psbA-trnH in this context.
• HTS-based DNA metabarcoding supports traceability and quality control for medicinal plant products.