花椒及其混淆品的rDNA ITS区序列分析与鉴别

目的研究不同居群的花椒及其混淆品的rDNA ITS区碱基序列的特征及其差异，为花椒的鉴别提供可靠的分子标记。方法运用PCR产物直接测序和克隆测序法对甘肃、陕西、四川、河北等7个花椒居群及3个混淆种的rDNA ITS区(包括ITS1，5.8S，ITS2)碱基序列进行序列测定。结果首次报道花椒ITS区的碱基序列，序列总长度为619-620 bp，长度变异较少，与混淆种长度仅相差4 bp。花椒各居群中，rDNA ITS区碱基序列有15个变异位点、12个信息位点、3个特异性识别位点。与混淆品间的碱基差异则较为显著，多达71个变异位点，有4个花椒特异性识别位点。结论依据花椒ITS区的序列特征可准确鉴别各居群的花椒及其混淆品；亲缘关系密切的花椒居群在地理位置上也非常靠近；rDNA ITS序列特征可作为花椒种内和种间鉴别的有效分子标记。     

Differentiation of the traditional Chinese medicinal plants Euphorbia humifusa and E. maculata from adulterants by TaqMan real-time polymerase chain reaction

DNA sequence analysis of the rDNA internal transcribed spacer 1 (ITS1) and TaqMan real-time polymerase chain reaction were exploited for their applications in the differentiation of the traditional chinese medicinal plants euphorbia humifusa and e. maculata from three related adulterants e. hypericifolia, E. atoto and E. prostrata. The data demonstrated that variations in the ITS1 regions were very low at the intra-species level but extremely high at the inter-species level, so that they could be easily distinguished at the DNA level. The sequence difference allowed an effective and reliable differentiation of E. humifusa and E. maculata from the adulterants by TaqMan real-time PCR.     

覆盆子及其近缘混淆品的PCR-RFLP鉴别研究

目的 建立一种覆盆子特异性的分子鉴别方法。方法 通过对覆盆子及其混淆品的ITS序列进行测序分析,根据差异位点设计限制性内切酶,采用聚合酶链反应-限制性片段长度多态性方法(polymerase chain reaction restriction fragment length polymorphism,PCR-RFLP)进行鉴别,建立并优化PCR鉴别方法,并对其稳定性和适用性进行考察与验证。结果 设计的引物可实现对覆盆子及其混淆品序列的扩增,扩增产物为800 bp大小的条带,通过对限制性内切酶MboI进行酶切后的片段长度进行分析,仅覆盆子的序列可被酶切形成2个片段,而混淆品的序列不能被切开,从而特异性鉴别是否为覆盆子。结论 本实验建立的PCR-RFLP方法可用于鉴别覆盆子。     

Authentication of stems of Dendrobium officinale by rDNA ITS region sequences

The rDNA ITS regions of five Dendrobium species were sequenced. Each Dendrobium species was found to have a unique sequence in the ITS region, so that they could be easily distinguished at the DNA level. The aligned 644 bp of the ITS region includes 235 bp ITS1, 163 bp 5.8S, and 246 bp ITS2. One hundred and eighty-nine sites are variable. The sequences of D. officinale could be easily distinguished from the other four adulterant species according to the sequence variation at 11 sites, 7 in ITS1, 1 in 5.8S, and 3 in ITS2. These could be used as molecular characters to distinguish the stems of D. officinale from the adulterants.     

Molecular authentication of the traditional Tibetan medicinal plant Swertia mussotii

Swertia mussotii is an important species in Tibetan folk medicine. However, it is quite expensive and frequently adulterated, so reliable methods for authentication of putative specimens and preparations of the species are needed to protect consumers and to support conservation measures. We show here that the chloroplast (cp) DNA RPL16 intron has limited utility for differentiating S. mussotii from closely related species, since the cpDNA RPL16 sequences are identical in S. mussotii and two other species of Swertia. However, the rDNA internal transcribed spacer (ITS) sequences differ significantly between S. mussotii and all of 13 tested potential adulterants. Thus, the ITS region provides a robust molecular marker for differentiating the medicinal S. mussotii from related adulterants. Therefore, a pair of allele-specific diagnostic primers based on the divergent ITS region was designed to distinguish S. mussotii from the other species. Authentication by allele-specific diagnostic PCR using these primers is convenient, effective and both simpler and less time-consuming than sequencing the ITS region.     

药用植物束花石斛、流苏石斛及其形态相似种的PCR-RFLP鉴别研究药用植物束花石斛、流苏石斛及其形态相似种的PCR-RFLP鉴别研究

目的建立简易的采用rDNA ITS区作为分子标记对中药石斛的基源植物进行分子鉴定的技术。方法 用聚合酶链反应—限制性片段长度多态性(PCR-RFLP)方法获得ITS片段的限制性图谱。束花石斛及其形态相似种的PCR扩增产物用Cla I和Apa LI酶切,流苏石斛及其形态相似种的PCR扩增产物用Sph I酶切。结果根据预测的PCR-RFLP图谱,可以鉴别药用植物束花石斛、流苏石斛及它们的形态相似种。用这种方法鉴定了市场上收集的25件商品束花石斛、流苏石斛新鲜药材的原植物。结论rDNA ITS的PCR-RFLP可用于鉴定石斛药材的原植物,具有简便、费用低的优点。     

Molecular authentication of the ethnomedicinal plant Sabia parviflora and its adulterants by DNA barcoding technique

Sabia parviflora Wall. ex Roxb. is a traditional herb widely used by Chinese people, especially by the Buyi ethnic group which resides in Guizhou and Yunnan provinces. According to the Chinese Ethnic Pharmacopeia, the species is commonly used for soothing the liver and for the treatment of icteric hepatitis, hemostasis, and inflammation. However, due to the similar morphological characters of Sabia species and higher market demands, there are many substitutes and adulterants of S. parviflora. In this study, the differential identification of 6 Sabia species and 7 adulterants were investigated through DNA sequence analysis of three candidate DNA barcodes (trnH-psbA, rbcL-α, matK). Based on sequence alignments, we concluded that not only the trnH-psbA spacer sequence can distinguish S. parviflora from other Sabia species, but the matK + rbcL-α sequences also can differentiate it from the substitutes and adulterants. The classification tree of all samples based on rbcL-α sequences indicated that the rbcL region can identify samples into a family/genus level. Our results suggest that the three candidate barcodes can be used for the identification of S. parviflora and to distinguish it from common substitutes or adulterants.     

Application of sequence characterized amplified region (SCAR) analysis to authenticate Panax species and their adulterants.

A 420-bp RAPD fragment from Panax quinquefolius was converted to a sequence characterized amplified region (SCAR) marker. The main difference between the SCAR of P. quinquefolius and its homolog in P. ginseng is the presence of a 25 bp insertion in the latter. Primers derived from this sequence were successfully used to authenticate six Panax species and two common adulterants.     

基于ITS序列鉴别特色民族药材土牛膝及其混伪品的研究

目的:利用DNA条形码对特色民族药材土牛膝(粗毛牛膝、野生牛膝和柳叶牛膝)及其混伪品进行分子鉴定.方法:利用DNA条形码方法,分别对土牛膝及其混伪品的ITS和MatK基因片段进行扩增并双向测序,使用Codon?Code?Aligner软件对扩增序列进行拼接,用MEGA软件对数据比对分析,并基于K2P模型进行遗传距离分析...     

基于ITS2序列鉴别维吾尔药材薰衣草及其混伪品

建立了基于ITS2序列鉴别维吾尔药材薰衣草及其混伪品(全叶青兰和夏枯草)的方法.对维吾尔药材薰衣草及其混伪品的ITS2 序列进行PCR扩增和双向测序,使用CodonCode Aligner软件对测序峰图进行序列拼接,用MEGA 6.0 软件对拼接后的序列进行多重比对.并计算种内、种间遗传距离,构建NJ 系统聚类树,预测...     

金钱白花蛇及其伪品的Cyt b基因片段序列分析和PCR鉴别研究

对金钱白花蛇及其伪、混品药材和原动物的Cyt b基因片段的序列分析发现,该基因片段在金钱白花蛇及其伪品间的差异远远大于金钱白花蛇种内个体间的差异,是理想的用于鉴别金钱白花蛇及其伪混品的分子遗传标记。在对Cyt b基因片段序列分析的基础上,设计了金钱白花蛇PCR鉴别的一对高度特异性引物BuL-1和BuH-1。结果表明,该对引物在对金钱白花蛇的PCR鉴别中,用60℃～65℃的复性温度,可以100%检出金钱白花蛇,误检率和漏检率为0,并能在混合的药材粉末中检测出被检样品中是否含有金钱白花蛇组份。本研究还表明PCR鉴别将有可能成为中成药复方组分鉴别的一种新手段。     

Genetic polymorphism of medicinally-used Codonopsis species in an internal transcribed spacer sequence of nuclear ribosomal DNA and its application to authenticate Codonopsis Radix

Codonopsis Radix has been prescribed as the roots of Codonopsis pilosula, C. pilosula var. modesta and C. tangshen in Chinese Pharmacopoeia. In order to find out genetic markers for identifying the 3 taxa and to authenticate Codonopsis Radix, the molecular analysis of the internal transcribed spacer sequence of nuclear ribosomal DNA was conducted on Codonopsis plants collected widely from Gansu Prov. and Chongqing city of China, the main producing areas of Codonopsis Radix. Significant genetic polymorphism was observed, represented by 11 types of ITS sequences in C. pilosula, 5 types in C. pilosula var. modesta and 5 types in C. tangshen. Among the determined sequences, 1, 1 and 2 types were thought to be of pure lines of each taxon, respectively, designated as types P0, PM0, T1 and T3, and the rest might be derived from hybridization. Hybrid lines were inferred to be resulting from the combination of these pure lines. The informative sites for discriminating the 3 taxa were detected at the nucleotide positions 122nd, 226th, 441st and 489th from upstream of the ITS sequence. For discrimination of the types of C. tangshen, including one type T0 registered in GenBank, the nucleotides at positions 135th, 489th and 500th were informative. Botanical sources of the crude drugs produced in a wide range of the southeast Gansu Prov. were C. pilosula, just those from Wenxian of Gansu Prov. were C. pilosula var. modesta. The crude drugs produced in Chongqing were derived from C. tangshen.     

Application of 3'-mismatched reverse primer PCR compared with real-time PCR and PCR-RFLP for the rapid detection of 23S rDNA mutations associated with clarithromycin resistance in Helicobacter pylori

Helicobacter pylori clarithromycin (Cla) resistance dramatically reduces efficacy of eradication therapy. In this study, 3'-mismatched reverse primer PCR (3M-PCR), real-time PCR (LightCycler), and PCR-RFLP assays were investigated to determine their sensitivity for detecting clarithromycin resistance associated with 23S rDNA mutations (A2142G, A2142C, and A2143G). For 84.8% (123/145) of isolates, the same allelic type was detected by each method although methods differed in efficiency of detecting mutations in cultures either containing mixtures of two alleles (24 isolates), or that were dual allelic variants (two isolates). The novel 3M-PCR assay format was the most sensitive, detecting all alleles at > or =0.02 ng/microl in DNA mixtures, and thus provides more precise information to guide clinical management of patients at risk of treatment failure.     

通关藤及其常见混伪品的ITS2条形码鉴别研究

目的:采用ITS2序列分析,对通关藤及其混淆品进行鉴别,确保用药安全。方法:从GenBank下载通关藤序列,使用MEGA5.0软件对测序序列及下载序列进行对比分析,统计变异位点、计算遗传距离、构建样品NJ树,运用NCBI Blast进行物种鉴定,并与性状鉴别结果进行核对。结果:ITS2序列分析与遗传距离计算结果显示各通关藤样品间有明显差异,NJ树聚类结果能明显区分通关藤正品与伪品。结论:ITS2可准确鉴别通关藤及其伪品,可用于中药材真伪的快速鉴别,应用前景广阔。     

艾叶及其常见混伪品的分子鉴定

目的：对艾叶及其几种常见混伪品进行分子鉴定。方法：通过聚合酶链式反应（PCR）法直接测序,对艾及其8种混伪品进行核糖体DNA内转录间隔区片段2（ITS2）扩增并双向测序,所得序列经CodonCodeAligner拼接后,用系统发育软件MEGA4．0进行相关数据分析,同时利用邻接（NJ）法构建系统聚类树。结果：艾叶基原植物艾ITS2序列长度为225bp,种内平均Kimura．双参数（K2P）遗传距离（0．000）小于其与混伪品的种间平均K2P遗传距离（0．022）;由所构建的系统聚类树图可以看出,艾具有单系性,同时又与其他混伪品明显分开。结论：ITS2序列作为DNA条形码可以方便快捷地鉴别中药材艾叶及其混伪品,可为其质量评价及临床安全用药提供重要的分子鉴别依据。     

枫斗类石斛rDNA ITS区的全序列数据库及其序列分析鉴别

目的建立枫斗类石斛的rDNA ITS区碱基全序列数据库,利用该数据库对枫斗类石斛待检种进行准确鉴别。方法对枫斗类石斛的rDNA ITS区进行了PCR扩增、测序,运用CLUSTRAL,MEGA等软件以及枫斗类石斛rDNA ITS区全序列数据库对待检种rDNA ITS区进行序列分析鉴别。结果建立了21种枫斗类石斛的rDNA ITS区全序列数据库, 枫斗类石斛在该区的种间差异显著而稳定,转换和颠换总数为11～122,变异位点数为341,信息位点数为195。与外类群植物云南石仙桃间的差异较大,转换和颠换总数为131～161。枫斗类石斛居群间的差异较小,转换和颠换总数为0～6。结论利用枫斗类石斛的全序列数据库及遗传分析软件,通过对待检种rDNA ITS区进行序列测定,可以成功鉴别属于数据库中枫斗类石斛的待检种。     

两种豆科药材及其混伪品的可溶性蛋白质电泳鉴别

目的：对赤小豆、决明子及其混伪品进行电泳鉴别,并考察考马斯亮蓝G－250的染色效果。方法：可溶性蛋白质凝胶电冰。结果：赤小豆、决明子及其混伪品的电泳图谱存在显著差异。结论：电泳图谱可作为赤小豆、决明子及其混伪品的鉴别依据,考马斯亮蓝G－250可用于电泳鉴别。     

DNA barcodes for discriminating the medicinal plant Scutellaria baicalensis (Lamiaceae) and its adulterants

Scutellaria baicalensis GEORGI (Lamiaceae) is the botanical origin of the well-known traditional Chinese medicine "Huang Qin" (Radix Scutellariae). Due to overexploitation that had induced a decline in natural sources, the dried roots of its congeners, S. amoena, S. rehderiana, and S. viscidula, have been used to adulterate it in recent years. This practice may cause a series of inconsistent therapeutic effects and quality control problems in the herbal medicine industry. Hence, we sequenced and analyzed three candidate DNA barcodes, the ribosomal RNA maturase gene (matK), the ribulose-1,4-bisphosphate carboxylase large subunit gene (rbcL), and the psbA-trnH intergenic spacer (psbA-trnH), to discriminate S. baicalensis and its adulterants. All candidate DNA barcodes had been successfully amplified from leaf samples. Comparatively, only psbA-trnH had been yielded from commercially prepared crude drug samples. Based on the sequence divergence, rbcL can assign S. baicalensis and its adulterants into the correct family and genus, whereas, either matK or psbA-trnH can accurately discriminate S. baicalensis and its adulterants. We proposed the multilocus barcodes rbcL+psbA-trnH for the species identification of S. baicalensis and its adulterants, and the unique barcode psbA-trnH for the authentication of commercial Radix Scutellariae. The DNA barcoding technique could be applied to the quality control of "Huang Qin"-based medicinal preparations and to the management of medicinal herb trade in the markets.     

基于DNA条形码技术鉴定蒙药材刺柏叶及其混淆品

目的：基于DNA条形码技术鉴别蒙药材刺柏叶及其混淆品。方法：采用国际通用的条形码序列 ITS2、psbA-trnH、matK和rbcL,对刺柏叶及其混淆品圆柏叶共计11份样品进行DNA提取、扩增,采用CodonCode Aligner进行序列拼接,并用MEGA软件对拼接序列进行变异位点分析、邻接(NJ)聚类分析,并计算其平均种内、种间遗传距离。结果：4对引物的PCR扩增产物测序成功率分别为ITS2 100%、 psbA-trnH 100%、rbcL 100%、matK 0%;ITS2序列和psbA-trnH序列均可通过变异位点比较区分刺柏叶及其混淆品;NJ聚类分析的结果显示,psbA-trnH序列的NJ聚类树中刺柏叶与圆柏叶均能分别聚为一支,且psbA-trnH序列的平均种间遗传距离明显大于平均种内遗传距离。结论：psbA-trnH序列能有效区分圆柏叶与刺柏叶,可作为鉴别刺柏叶及其混淆品圆柏叶的条形码序列,为蒙药材刺柏叶及其混淆品的鉴别提供支持。     

Application of real-time scorpion PCR for authentication and quantification of the traditional Chinese medicinal plant Drynaria fortunei

DNA sequence analysis of the trnl-trnF spacer region and real-time scorpion polymerase chain reaction were exploited for their applications in the differentiation and quantification of the traditional Chinese medicinal plants Drynaria fortunei from five related adulterants: D. mollis, D. quercifolia, D. rigidula, D. sparsisora, and Pseudodrynaria coronans. The data demonstrated that variations in the trnl-trnF spacer regions were very low at the intraspecific level but extremely high at the interspecific level, meaning that they could be easily distinguished at the DNA level. The sequence difference allowed effective and reliable differentiation of D. fortunei from adulterants by real-time scorpion PCR. Furthermore, a quantification methodology was carried out to quantify D. fortunei.