Molecular authentication of Thai medicinal plant, Vitex glabrata, by PCR-RFLP

Several species in Vitex, a genus in the family Labiatae, are medicinal plants used in folk remedy in many countries with different effects. Vitex glabrata R. Br. is used as anthelmintic, wound healing and sexual enhancer, which are different from the uses of other Vitex species. These effects are related to the presence of ecdysteroids in the plant (1) since it has high amount of 20-hydroxyecdysone (2). Crude drugs of many Vitex species have similar appearance, which lead to confusion and misuse. Therefore, an accurate authentication of V. glabrata is essential for medicinal purpose. In this study, PCR-restriction fragment length polymorphism (PCR-RFLP) based on the chloroplast maturase K (matK) gene analysis was applied to identify V. glabrata from other Vitex species commonly found in Thailand. Among five Vitex species, a distinctive site recognize by a restriction enzyme HindIII in V. glabrata was found. A pair of new primers, Vt1110matKF and Vt1516matKR, was designed based on the sequence of V. glabrata to amplify a smaller fragment of 407 bp in length from genomic DNAs of the leaves of these five species. Only the PCR product of V. glabrata could be digested with HindIII into two fragments of 324 bp and 83 bp while the other species remained undigested. This result suggests that PCR-RFLP analysis is an effective and accurate method for authentication of V. glabrata.

Acknowledgement: the Faculty of Pharmaceutical Sciences Research Funds, Faculty of Sciences, Chulalongkorn University, Thailand

References: 1. Báthori M, Pongrácz Z (2005) Curr Med 12:153–172.

2. Werawattanametin K (1986)J Nat Prod 9(2):365–366