Molecular authentication of the medicinal herb Ruta graveolens (Rutaceae) and an adulterant using nuclear and chloroplast DNA markers

Abstract

ABSTRACT. Dried parts of different plant species often look alike, especially in powdered form, making them very difficult to identify. Ruta graveolens, sold as a dried medicinal herb, can be adulterated with Euphorbia dracunculoides. The genomic DNA was isolated from the leaf powder (100 mg each) using the modified CTAB method. Internal transcribed spacer sequences of nuclear ribosomal DNA (nrDNA-ITS), and chloroplast spacer sequences (rpoB and rpoC1) are regarded as potential genes for plant DNA barcoding. We amplified and sequenced these spacer sequences and confirmed the sequences with a BLAST search. Sequence alignment was performed using ClustalX to look for differences in the sequences. A DNA marker was developed based on rpoB and rpoC1 of the nrDNA-ITS for the identification of the adulterant E. dracunculoides in samples of R. graveolens that are sold in local herbal markets. Sequence-characterized amplified region markers of 289 and 264 bp for R. graveolens and 424 bp for E. dracunculoides were developed from dissimilar sequences of this ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 10 (4): 2806-2816 2807Molecular typing of R. graveolens and E. dracunculoides nrDNA-ITS to speed up the authentication process. This marker successfully distinguished these species in extracted samples with as little as 5 ng DNA/µL extract.

DNA Barcode ITS Effectively Distinguishes the Medicinal Plant Boerhavia Diffusa from Its Adulterants

“…This result is consistent with a previous report that psbA-trnH does not show any variation for closely-related Cycad species [26] . Hence, ITS1 may be a better barcode region for distinguishing the species of Boerhavia , although ITS2 has been widely used to distinguish the plant species [27] . This study clearly indicates that DNA barcoding using candidate like ITS1 is a reliable method for differentiating B. diffusa from the other three species, which can also be applied to rapid identification of medicinal plants and their adulterants or substitutes.…”

Development of genetic markers for Ochradenus arabicus (Resedaceae), an endemic medicinal plant of Saudi Arabia

“…The rpoC1 gene has base deletions and insertions at sites 4,5,10,26,27,28 and 8,13,17,29,77,78,79,80,82,83,86,respectively (Figure 6). Similarly, this gene has been used successfully for the authentication of Ruta graveolens from its adulterant Euphorbia dracunculoids (Al-Qurainy et al, 2011b). These plastid regions have performed well in DNA barcoding in terms of being amplifiable with a limited range of PCR conditions and primer sets (Liu et al, 2011).…”

“…Sequencing-and non-sequencing-based markers have been used in many medicinal and non-medicinal plant species for the detection of adulterants in the local herbal markets (Khan et al, 2011;Al-Qurainy et al, 2011a). Currently, internal transcribed spacer sequences of nrDNA and chloroplast DNA markers are used for the accurate identification and authentication of plant species (Chase et al, 2005;CBOL Plant Working Group, 2009;Devey et al, 2009;Fazekas et al, 2009;Chen et al, 2010;Al-Qurainy et al, 2011b). Thus, variations in the DNA sequences are very helpful in the development of unique markers, which could be used as a DNA barcode for that species.…”

Molecular authentication of multi-species honeysuckle tablets

“…In recent years, several technologies such as morphology, chemical analysis (Xie et al, 2006), biological activity assay (Bai et al, 1997;Liu et al, 2006), and DNA molecular markers (Yip et al, 2007;Al-Qurainy et al, 2011;Guo et al, 2011) have been developed for authenticating raw herbal materials. With their characteristics of non-reliance on morphology, reproducibility, extreme reliability, and easy manipulation, DNA-based molecular tools are urgently needed in authenticating raw herbal materials.…”