Fluorescent signal-based molecular method for identification and quantification of adulteration in Panax ginseng from raw materials to processed products

Economically motivated and inadvertent adulteration of Panax ginseng alters the dosage accuracy and composition of ginseng products, ultimately compromising their efficacy and safety. Reliable methods to identify and quantify such adulteration remain inadequately established. In this study, a molecular quantification method (Herb-Q) that integrates species-specific single nucleotide polymorphism (SNP) detection with allelic fluorescence signal was developed to identify and quantify ginseng and its adulterants. Three SNPs, distinguishing P. ginseng, P. quinquefolius, and P. notoginseng from other species, were screened from 117 chloroplast genomes and validated using 48 actual samples. Herb-Q exhibits high repeatability and linearity (R² > 0.9900), with limits of detection and quantification down to 1 ng. Its applicability to complex matrices was validated by testing 10 batches of herbal products (HPs) in powder, tablet, and pill forms, of which five were found to be adulterated, with adulteration levels ranging from 6 % to 86 %. The standard curve, correlating allelic fluorescence signals with weight, was generated by introducing six weight ratios of adulterants, and target species quantification was achieved using external standards. The quantitative accuracy of Herb-Q in mixed raw materials and processed products exceeded 95 %. This study presents a novel tool for the quantitative tracking of P. ginseng throughout the food product supply chain and demonstrates its promising potential to combat food labeling fraud.