Medicinal plants comprise an important source for disease cure in many countries. Nowadays, quality control of local market dealing with medicinal plants products is an important task. Due to adulteration and misconduct in local medicinal markets, the customers’ health may be in danger. Ziziphora (Kakuti) is an important medicinal plant product in Iran that is used for several disorders. The leaf of Ziziphora species, mainly Ziziphora clinopoidodes and Z. tenuior resemble Thymus kotschyanus, Th. vulgaris, Th. daenensis, Th. pubescens, and Th. trautvetteri in both morphology and odor. Therefore, Thymus species are usually collected along with Ziziphora mistakenly and sold as Kakuti. To avoid this kind of adulteration, this investigation was performed with the following aims: 1- to check for Kakuti products adulteration or misidentification in local markets, and 2- to provide barcode gap for medicinal species of Ziziphora, and Thymus. Market-sold plant samples (leaves) and original reference plant species were compared by morphology, odor as well as Internal transcribed spacer (ITS) sequences. Different molecular analysis, such as genetic distance determination and phylogenetic tree construction were carried out. These reports showed that all randomly studied market samples differ from true Ziziphora species. For constructing the barcode gap, we used ITS (nuclear), trnL-F intergenic spacer (trnL-F), and Maturase K (matk) (chloroplast) sequences. The reports indicated that ITS sequences are an efficient molecular marker to produce barcode gap and differentiating Ziziphora from Thymus species. This is the first report on Ziziphora barcode.
