Panax ginseng C.A. Meyer (Korean ginseng) is one of the most valuable medicinal plants, recognised for its
neuroprotection and other beneficial health effects. It is present in a wide range of food products, namely plant
food supplements (PFS) and herbal infusions. However, other Panax species, having distinct therapeutic effects,
are also known as ginseng, pointing out the need of authenticating such products. The present work aims at
proposing a new high-resolution melting (HRM) method to differentiate five Panax species (P. ginseng,
P. quinquefolius, P. notoginseng, P. japonicus and P. trifolius), targeting the gene encoding the dammarenediol
synthase, involved in the biosynthesis pathway of ginsenosides. A Panax-specific real-time PCR assay was successfully
developed with high analytical performance parameters (Efficiency = 100.5 %, R2 = 0.995, dynamic
range 10 ng-1 pg of ginseng DNA). Panax DNA was detected in 17 out of 23 ginseng-containing commercial
foods, including herbal infusions and PFS. For the first time, HRM analysis differentiated five Panax species with
high level of confidence (>98 %), which corroborated sequencing data. Fourteen products were successfully
clustered, being all except one in accordance with their labelling statements. Therefore, the present work proposes
a reliable and high-throughput tool to authenticate ginseng products that could be useful for control
laboratories.
The authors acknowledge the support of project UIDB 00690/2020
funded by FCT/MCTES through national funds. The authors are grateful for the supply of leaves from the Botanical Garden of Edinburgh
(Edinburgh, Scotland), Botanical Garden of University of Porto (Porto,
Portugal), Botanical garden of UTAD (Vila Real, Portugal), as well as to
the voucher seeds from the RBG (Kew, Ardingly, West Sussex, UK),
USDA-ARS Germplasm (Beltsville, MD, USA) and NCRPIS/Iowa State
university (Ames, IA, USA).
