Development of species-specific chloroplast markers for the authentication of Gynostemma pentaphyllum and their distribution in the Korean peninsula.

Gynostemma pentaphyllum is a traditional oriental medicinal herb used as tea since ancient time. Among Gynostemma species, G. pentaphyllum has more active chemical components and better therapeutic effect. It is used to cure depression, diabetes, anxiety, hyperlipidemia, fatigue, immunity, cancer, and oxidative stress. Overexploitation of G. pentaphyllum for its medicinal benefits has been on a rise, due to which they are adulterated or mistakenly identified with other members of Gynostemma species. Hence, we used chloroplast universal regions such as ycf3, accD, petD, psbB and their polymorphism to distinguish G. pentaphyllum from other Gynostemma species. By using the species-specific primers derived from the above regions, we established a multiplex allele-specific PCR for the authentication of G. pentaphyllum from other species. Thus the PCR reaction produced unique amplicons of size 244 bp and 438 bp for G. pentaphyllum amplified by the primers flanking ycf3, and accD regions respectively. While a 607 bp, and 787 bp amplicons from the primers targeting psbB, and petD regions distinguished G. longipes, G. burmanicum, and G. pubescens species. Moreover, these primers were successful to analyze the dried tea samples of Gynostemma as well. Thus, the developed molecular markers could authenticate different Gynostemma species as well as its products thereby preventing the mistaken-identity of this medicinal herb.