Quality ecotype of Panax quinquefolium L. based on heredity-chemistry-ecology characteristics / 药学学报

Medicinal materials in China differ in quality by different ecological types. Our research group found that there were two ecotypes of domestic Panax quinquefolium L. according to the characteristics of ginsenosides, inside versus outside Shanhaiguan. The genetic and ecological mechanisms of quality variation of Panax quinquefolium L. is unknown. Based on the genetic-chemical-ecological strategy, transcriptome and HPLC technology were used for comprehensive correlation analyses of transcriptomic data, ginsenoside content and environmental climate ecological factors. The transcriptomic results showed that key genes of ginsenoside biosynthesis, such as HMGR, AS and FPS, were significantly down-regulated in the inside Shanhaiguan ecotype. HPLC results showed that the quality of outside Shanhaiguan ecotype Panax quinquefolium L. was higher than that of the inside ecotype, with the content of ginsenosides in outside Panax quinquefolium L. was higher than that of inside ecotype except Rb2. Correlation analyses revealed that content of Panax quinquefolium L. ginsenoside is positively related to the expression levels of ginsenoside biosynthesis key genes (MK, HMGS, HMGR, and AS), and negatively related to the expression of glycosyl transferase (GT). The content of ginsenosides is negative related with climate factors, such as temperature, sunshine, and is positively related with moisture in both ecological environments. This study has provided a new mechanistic insight into the quality variations of two ecotypes for Panax quinquefolium L. and established a scientific basis for studying the ecological factors for the quality of traditional Chinese medicine.

Identification of radix et rhizoma clematidis and its adulterants using DNA barcoding / 药学学报

This study provides the candidate sequences in the identification of Radix et Rhizoma Clematidis and its adulterants using DNA barcoding. We amplified and sequenced the region psbA-trnH, with the data of 284 sequences from GenBank, the differential intra- and inter-specific divergences, genetic distance, barcoding gap were used to evaluate five barcodes, and the identification efficiency was assessed using BLAST1 and Nearest Distance methods. The results showed that psbA-trnH barcodes performed high identification efficiency and inter-specific divergences among the five different DNA barcodes. Analysis of the barcoding gap and NJ tree showed psbA-trnH was superior to other barcodes. Based on the identification and PCR amplification efficiency, psbA-trnH can be the ideal barcode to identify Radix et Rhizoma Clematidis and its adulterants accurately.

Molecular identification in genus of Lilium based on DNA barcoding / 药学学报

To establish a new method for identifying genus of Lilium by DNA barcoding technology, ITS, ITS2, psbA-trnH, matK and rbcL sequences were analyzed in term of variation of inter- and intra-species, barcoding gap, neighbor-joining tree to distinguish genus of Lilium based on 978 sequences from experimental and GenBank database, and identification efficiency was evaluated by Nearest distance and BLAST1 methods. The results showed that DNA barcoding could identify different species in genus of Lilium. ITS sequence performed higher identification efficiency, and had significant difference between intra- and inter-species. And NJ tree could also divide species into different clades. Results indicate that DNA barcoding can identify genus of Lilium accurately. ITS sequence can be the optimal barcode to identify species of Lilium.

Specific PCR molecular identification of Dendrobium chrysotoxum / 中草药

Objective: To design a pair of PCR primers that could identify Dendrobium chrysotoxum specifically, to optimize the system of PCR detection, and to establish a method to identify D. chrysotoxum rapidly and accurately. Methods: From GenBank database, rDNA 170 ITS sequences in the plants of Dendrobium Sw. were downloaded and compared with all sequences using MEGA 5.0; The variation sites were located, and a pair of specific primers in the non-conservative district were designed. PCR amplification was performed using the specific primers with 35 DNA templates in the plants of Dendrobium Sw., D. chrysotoxum was positive. Results: D. chrysotoxum could be specifically amplificated by specific primers when the annealing temperature was raised to 58 °C, while other plants of Dendrobium Sw. were shown as negative, and the sensitivity of the primer could reach 0.69 ng/μL. Conclusion: This study designs a method that could identify D. chrysotoxum specifically. Using this specific primer could identify D. chrysotoxum rapidly and accurately from the homologous species. This method is well-performed in specificity, and it is more simple, convenient, efficient, and accurate than other methods, such as morphological and microscopical identification, chromatograph, and spectral method.

Identification of gentianae macrophyllae radix using the ITS2 barcodes / 药学学报

DNA barcoding is a rapidly developing frontier technology in the world and will be useful in promoting the quality control and standardization of traditional Chinese medicine. Until now, many studies concerning DNA barcoding have focused on leaf samples but rarely on Chinese herbal medicine. There are three issues involved in DNA barcoding for traditional Chinese medicinal materials: (1) the extraction methods for total DNA of the rhizomes of the medicinal materials; (2) intra-specific variation among samples from different places of origin; (3) accuracy and stability of this method. In this study, Gentianae Macrophyllae Radix was used to verify the stability and accuracy of DNA barcoding technology. Five regions (ITS2, psbA-trnH, matK, rbcL, and ITS) were tested for their ability to identify 86 samples of Gentianae Macrophyllae Radix and their adulterants. After improving the DNA extraction method, genomic DNA from all samples was successfully obtained. To evaluate each barcode's utility for species authentication, PCR amplification efficiency, genetic divergence, and species authentication were assessed. Among all tested regions only ITS2 locus showed 100% of PCR amplification and identification efficiencies. Based on the established method, we successfully identified two samples of Gentianae Macrophyllae Radix bought in pharmacy to the original species.