RESUMEN
Desmodium caudatum (Thunb.) DC, is an ever-green plant widely used in the central and southern China with great economic value for their medical values on fever, dysentery, gastroenteritis, rectal prolapse, snake bites, mastitis, and boils carbuncle. Despite its extensive uses as a traditional Chinese medicine, no systematic research on the identification of Desmodium caudatum has been reported. In this study, traditional pharmacognostical identification including the botanical origin and morphological characters, medicinal material characters, microscopic characters, physicochemical parameters determination and phytochemical screening, and DNA barcoding analysis were employed to establish an accurate and effective identification system of Desmodium caudatum. In addition, the molecular pharmacognosy study was adopted in order to identify the samples more accurately. The ITS loci of the nuclear genome and psbA-trnH loci of the chloroplast genome were selected and evaluated, which were the most variable loci. The study will be beneficial to the development of the quality standard and the identification of species.
Asunto(s)
ADN de Plantas/genética , Fabaceae/química , Fabaceae/genética , Código de Barras del ADN Taxonómico , Fabaceae/clasificación , Farmacognosia , Análisis de Secuencia de ADNRESUMEN
Abstract Various traditional systems of medicine enlightened the importance of Premna microphylla Turcz., Lamiaceae, medicinally. The present study was carried out to provide a scientific basis of the identification and the authenticity of P. microphylla with the help of pharmacognostical parameters, which is not done before. Roots, stems, and leaves of P. microphylla were collected for pharmacognostical studies involving macros, microscopic evaluation, physicochemical parameters analysis like fluorescence analysis and thin layer chromatography, in addition with DNA barcodes of internal transcribed spacer and psbA-trnH regions. Transverse section of root indicated the presence of stone cell bands. Transverse section of stem showed the presence of stone cells and vessels. Transverse section of leaf midrib revealed the presence of shaft type of porosity. Microscopic studies of powder revealed the presence of cork cells, fibers, vessels, nonglandular hairs, stone cells and glandular scale cells. Thin layer chromatography of the extract revealed the presence of oleanolic acid in P. microphylla with specific R f values. Identification through DNA barcode showed the sequence of internal transcribed spacer region was novel while the sequence of psbA-trnH region displayed no differences from known sequence. The observations confirmed that P. microphylla has an obvious pharmacognostical characteristics, which will be useful toward providing a reliable basis for identification, purity, quality and classification of the plant.