The use of DNA barcoding to avoid adulteration in olive plant leaf products

Abstract

Abstract. Partovi R, Iranbakhsh A, Sheidai M, Ebadi M. 2020. The use of DNA barcoding to avoid adulteration in olive plant leaf products. Asian J For 5: 42-47. The leaves of olive plant species, either the cultivated (Olea europaea) and the wild (O. europaea var. Cuspidata) have been used for medicinal uses in Iran. The first species leaves have been used to control the blood pressure, while the leaves of wild olive have been used for abortion by locals. Our preliminary inspection of the medicinal plant market revealed that the leaves of these two olive species were sold mistakenly to the consumers and their health might be at risk. Therefore, we performed this investigation to produce DNA barcodes for correct identification of these two olive species and also identify the potential adulteration in our local market. We used Internal transcribed spacer (ITS) as well as plastid genome trnL-F intergenic spacer and ribosomal protein L16 (rpL16) sequences. These sequences after alignment and curation produced DNA barcodes that can differentiate the two olive species from each other. The phylogenetic trees constructed also separated the samples of these olive species and confirmed the potential use of these short DNA sequences for olive barcoding. The present study revealed that some of the local shops mistakenly sell the wild olive leaves instead of the cultivated olive leaf to be used for blood pressure. This mistake endangers the health of pregnant women consumers if they carry a child. We suggest using a combination of nuclear ITS and plastid intergenic spacer (trnL-F and rpL16) regions for DNA barcoding of olive plants to avoid leaf product adulteration.