DNA-Based Herbal Teas’ Authentication: An ITS2 and <i>psbA-trnH</i> Multi-Marker DNA Metabarcoding Approach

Medicinal plants have been widely used in traditional medicine due to their therapeutic properties. Although they are mostly used as herbal infusion and tincture, employment as ingredients of food supplements is increasing. However, fraud and adulteration are widespread issues. In our study, we aime...

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Bibliographic Details
Main Authors: Jessica Frigerio, Giulia Agostinetto, Valerio Mezzasalma, Fabrizio De Mattia, Massimo Labra, Antonia Bruno
Format: Article
Language:English
Published: MDPI AG 2021-10-01
Series:Plants
Subjects:
Online Access:https://www.mdpi.com/2223-7747/10/10/2120
Description
Summary:Medicinal plants have been widely used in traditional medicine due to their therapeutic properties. Although they are mostly used as herbal infusion and tincture, employment as ingredients of food supplements is increasing. However, fraud and adulteration are widespread issues. In our study, we aimed at evaluating DNA metabarcoding as a tool to identify product composition. In order to accomplish this, we analyzed fifteen commercial products with DNA metabarcoding, using two barcode regions: <i>psbA-trnH</i> and ITS2. Results showed that on average, 70% (44–100) of the declared ingredients have been identified. The ITS2 marker appears to identify more species (<i>n</i> = 60) than <i>psbA-trnH</i> (<i>n</i> = 35), with an ingredients’ identification rate of 52% versus 45%, respectively. Some species are identified only by one marker rather than the other. Additionally, in order to evaluate the quantitative ability of high-throughput sequencing (HTS) to compare the plant component to the corresponding assigned sequences, in the laboratory, we created six mock mixtures of plants starting both from biomass and gDNA. Our analysis also supports the application of DNA metabarcoding for a relative quantitative analysis. These results move towards the application of HTS analysis for studying the composition of herbal teas for medicinal plants’ traceability and quality control.
ISSN:2223-7747