ABSTRACT
Objective:To accurately identify Bupleurum seeds by traditional morphological identification method combined with DNA barcoding technique. Method:A total of 41 seed samples on the market were collected and 75 ribosomal DNA internal transcribed spacer 2 (ITS2) sequences of 15 varieties were downloaded from the GenBank database as experimental materials. The seeds were measured and observed by stereomicroscope and vernier caliper, and their 1 000-grain weights were calculated. Genomic DNA was extracted from the seeds and used as a template, and ITS2 sequences were amplified using polymerase chain reaction (PCR) and bidirectional sequencing. Species identification was conducted based on BLAST method, neighbor-joining (NJ) phylogenetic tree method, Kimura two-parameter model (K2P) genetic distance method, and secondary structure of ITS2 sequence. Result:There were slight differences in the length, width, cross-section, and 1 000-grain weight among Bupleurum seeds from different origins. The ITS2 sequences of B. chinense seeds had 2 intraspecific variable sites and 3 haplotypes, the maximum intraspecific genetic distance (0.009) was far smaller than the minimum interspecific genetic distance (0.032). B. chinense and B. scorzonerifolium in the NJ phylogenetic tree were clustered into independent branches with good monophyletic property. The secondary structure of ITS2 sequences could make up for the shortcomings of NJ tree in identifying variants. The collected 41 seeds included 30 B. chinense seeds, 3 B. scorzonerifolium seeds, 5 B. falcatum seeds, 2 B. marginatum var. stenophyllum seeds, and 1 B. smithii var. parvifolium seeds. Conclusion:The B. chinense seeds on the market have problems of diverse sources and chaotic origins. Based on the combination of ITS2 gentic barcoding and seed morphological identification, the Bupleurum seeds can be accurately identified, which provides scientific bases for establishing the quality standard of Bupleurum seeds, standardizing the cultivation of B. chinense, and solving the quality problems of B. chinense from the source, and provides a reference for the accurate identification of other medicinal plant seeds or seed medicinal materials.
ABSTRACT
Objective:To construct a systematic identification system of Anemonis Flaccidae Rhizoma, and to evaluate the comprehensive quality of Anemonis Flaccidae Rhizoma from 16 regions in China, so as to lay a foundation for its origin selection and clinical medication safety. Method:The authenticity of Anemonis Flaccidae Rhizoma was quickly identified by traditional identification method and DNA barcode molecular identification technology, and HPLC-UV was used to determine the contents of 5 active ingredients in Anemonis Flaccidae Rhizoma. All high pressure chromatographic separations were performed with a Welch Ultimate XB-C18 column (4.6 mm×250 mm, 5 μm), the mobile phase consisted of acetonitrile-0.01% trifluoroacetic acid aqueous solution (30∶70) at a flow rate of 1.0 mL·min-1. The detection wavelength was set at 210 nm and the column temperature was maintained at 30 ℃. Result:The authenticity of Anemonis Flaccidae Rhizoma could be precisely and rapidly identified by ribosomal DNA internal transcribed spacer 2 (ITS2) sequence and traditional identification methods. BLAST comparative analysis found that medicinal materials from 16 areas were all Anemone flaccida. Based on the contents of multi-index components, it was shown that the total content of 5 triterpenoid saponins in Anemonis Flaccidae Rhizoma from Banqiao, Enshi, Hubei was the highest (10.59%), followed by Hezhang, Bijie, Guizhou (6.28%) and Duzhenwan, Changyang, Hubei (5.64%). Conclusion:DNA barcoding can be used as an effective supplement to the traditional identification technology, it can ensure the authenticity of Anemonis Flaccidae Rhizoma and the safety of clinical use. The comprehensive evaluation of multi-index components of HPLC and cluster analysis show that the quality of medicinal materials in Enshi, Changyang, Wufeng of Hubei, Bijie of Guizhou and Jinfoshan of Chongqing is superior, which can be considered as important origin of Anemonis Flaccidae Rhizoma.
