Development and Evaluation of a PCR Kit for Authentication of Panax quinquefolius L. with PCR-Restriction Fragment Length Polymorphism

Panax quinquefolius L. (American ginseng) and Panax ginseng C.A. Meyer are famous herbal medicines. Accurate authentication of the species has grown to be a significant impact. This study aims to develop a PCR kit for the authentication of Panax quinquefolius L. and Panax ginseng based on the nuclear internal transcribed spacer 2 (ITS2) gene with the improved PCR-restriction fragment length polymorphism (PCR-RFLP) method. The reagent components in the development work were prepared and determined by the kit consisting of the DNA extraction, PCR amplification, and restriction enzyme digestion systems. A total of 21 batches of Panax quinquefolius L. and Panax ginseng samples collected from different areas were validated. Their specificity, stability, and repeatability were evaluated. The purity of genomic DNA extracted was 1.73 ± 0.13 according to the ratio of A 260 / A 280 , and the mass concentration was 3.15 ± 0.22 μg/g (using the kit). PCR amplicons of Panax quinquefolius L. and Panax ginseng were 122 bp in length. After the PCR products were digested by restriction enzyme Hinf I, a distinct pattern exhibited in the species of Panax quinquefolius L. with two fragments of 40 bp and 80 bp respectively, whereas those from Panax ginseng in addition to adulterated samples could not. Evaluation confirmed that the DNA kit results were stable and repeatable after 10, 15, and 20 freeze–thaw cycles: the evaluation was 100% specific. The DNA kit proposed in the study can be used for the identification of Panax quinquefolius L.