Molecular authentication of the traditional medicinal plant Fallopia multiflora.

The root of Fallopia multiflora is one of the most widely used traditional Chinese medicines. However, it is often confused and substituted with the roots of F. multiflora var. ciliinervis, Pteroxygonum giraldii, Cynanchum auriculatum, and Stephania cepharantha. To establish a DNA polymorphism-based assay for the identification of F. multiflora, the nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) regions of six Fallopia species were sequenced and analyzed. Based on the diversity of ITS regions among the species the diagnostic primers PMITS28 and PMITS545, which amplified an expected 517-bp DNA fragment from F. multiflora DNA, were designed. No amplified product was observed when DNA from other species was used. This method can be used for the authentication of F. multiflora.