Molecular authentication of two medicinal plants Ligularia fischeri and Ligularia stenocephala using allele-specific PCR (AS-PCR) strategy

Ligularia fischeri (Gom-chi) and Ligularia stenocephala (Gon-dal-bi) are popular edible herbs in Korea. L. fischeri is used to treat jaundice, hepatitis, rheumatoid arthritis, and scarlet fever, while L. stenocephala is used to treat anxiety, weakness, and menstrual disorders. The herbal medicinal activities of these two herbs differ, but they are very difficult to distinguish based on their morphologies, especially in their dried forms. In an effort to distinguish these two plant species, we sequenced three barcoding genes in plastids, matK, rbcL, and trnH-psbA. From the analysis of sequence variations, we detected five single nucleotide polymorphisms (SNPs) between two the species. Allele specific (AS)-primers in the SNPs were employed in discrimination of the two species. Of the five AS-primer sets, one primer pair in matK gene showed reproducibly distinguishable PCR amplification between plants of L. fischeri and L. stenocephala. The method is reproducible and efficient, and is the first reported molecular method to discriminate between L. fischeri and L. stenocephala.