What's in the box? Authentication of Echinacea herbal products using DNA metabarcoding and HPTLC

Ancuta Cristina Raclariu; Carmen Elena Ţebrencu; Mihael Cristin Ichim; Oana Teodora Ciupercǎ; Anne Krag Brysting; Hugo de Boer

doi:10.1016/j.phymed.2018.03.058

What's in the box? Authentication of Echinacea herbal products using DNA metabarcoding and HPTLC

Phytomedicine. 2018 May 15:44:32-38. doi: 10.1016/j.phymed.2018.03.058. Epub 2018 Mar 21.

Authors

Ancuta Cristina Raclariu¹, Carmen Elena Ţebrencu², Mihael Cristin Ichim³, Oana Teodora Ciupercǎ⁴, Anne Krag Brysting⁵, Hugo de Boer⁶

Affiliations

¹ Natural History Museum, University of Oslo, P.O. Box 1172 Blindern, 0318 Oslo, Norway; Stejarul Research Centre for Biological Sciences, National Institute of Research and Development for Biological Sciences, Alexandru cel Bun Street, 6, 610004 Piatra Neamt, Romania.
² Research and Processing Center for Medicinal Plants Plantavorel S.A., Cuza Voda Street, 46, 610019, Piatra Neamt, Romania; Academy of Romanian Scientists, Splaiul Independentei, 54, 050094, Bucharest, Romania.
³ Stejarul Research Centre for Biological Sciences, National Institute of Research and Development for Biological Sciences, Alexandru cel Bun Street, 6, 610004 Piatra Neamt, Romania.
⁴ Research and Processing Center for Medicinal Plants Plantavorel S.A., Cuza Voda Street, 46, 610019, Piatra Neamt, Romania.
⁵ Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, P.O. Box 1066 Blindern, 0316 Oslo, Norway.
⁶ Natural History Museum, University of Oslo, P.O. Box 1172 Blindern, 0318 Oslo, Norway. Electronic address: hugo.deboer@nhm.uio.no.

PMID: 29895490
DOI: 10.1016/j.phymed.2018.03.058

Abstract

Background: Differences in regulatory policies between countries as well as a lack of appropriate standardized methods for the authentication and quality control of herbal products directly impact their quality and safety. Echinacea products are among the top-selling herbal products in Europe and the United States with indications for a broad range of ailments. The increased use of Echinacea species has led to concerns about adulterated products resulting from challenges in morphology-based identification, due to overlapping morphological variation, frequent hybridization between species, and deliberate adulteration.

Purpose: This study addressed the need for a novel analytical strategy in the authentication of herbal products.

Methods: A combination of high performance thin layer chromatography (HPTLC) and DNA metabarcoding was employed. Fifty-three Echinacea herbal products marketed across Europe were tested to evaluate the accuracy of these methods in plant identification and their potential for detecting substitutes, adulterants and other unreported plant constituents.

Results: HPTLC provides high resolution in the detection of Echinacea phytochemical target compounds, but does not offer information on the other species within the product. Alternatively, we showed that the limitation of HPTLC in detecting non-targeted species can be overcome by the complementary use of DNA metabarcoding. Using DNA metabarcoding, Echinacea species were detected in 34 out of the 38 retained products (89%), but with a lack of discriminatory resolution at the species level due to the low level of molecular divergence within the Echinacea genus. All of the tested herbal products showed considerable discrepancies between ingredients listed on the label and the ones detected using DNA metabarcoding, registering an overall ingredient fidelity of only 43%.

Conclusion: The results confirm that DNA metabarcoding can be used to test for the presence of Echinacea species and simultaneously to detect other species present in even highly processed and multi-ingredient herbal products.

Keywords: Authentication; DNA metabarcoding; Echinacea; HPTLC; Herbal pharmacovigilance; Herbal products.

MeSH terms

Chromatography, High Pressure Liquid / methods
Chromatography, Thin Layer / methods*
DNA Barcoding, Taxonomic / methods*
Drug Contamination
Echinacea / genetics*
Europe
Plant Preparations / analysis
Plant Preparations / chemistry
Plant Preparations / standards*
Quality Control

Substances

Plant Preparations