Molecular authentication of Panax species.

Using conserved plant sequences as primers, the DNA sequences in the ribosomal ITS1-5.8S-ITS2 region have been amplified and determined for six Panax species, P. ginseng C. A. Mey. (Oriental ginseng), P. quinquefolius L. (American ginseng), P. notoginseng (Burkill) F. H. Chen (Sanchi), P. japonicus C. A. Mey. (Japanese ginseng), P. trifolius L. and P. major Ting, as well as two common adulterants of ginseng, Mirabilis jalapa L. and Phytolacca acinosa Roxb. An authentication procedure based upon the restriction fragment length polymorphism (RFLP) in the region is able to differentiate between P. ginseng and P. quinquefolius, and to discriminate the ginsengs from the two common poisonous adulterants. Broader application of this approach to authenticate other morphologically similar Chinese medicinal materials is rationalised.