Sequence analysis of Chinese and Japanese Curcuma drugs on the 18S rRNA gene and trnK gene and the application of amplification-refractory mutation system analysis for their authentication

The botanical origins of Chinese and Japanese Curcuma drugs were determined to be Curcuma longa, C. phaeocaulis, the Japanese population of C. zedoaria, C. kwangsiensis, C. wenyujin, and C. aromatica based on a comparison of their 18S rRNA gene and trnK gene sequences with those of six Curcuma species reported previously. Moreover, to develop a more convenient identification method, amplification-refractory mutation system (ARMS) analysis of both gene regions was performed on plants. The ARMS method for the 18S rRNA gene was established using two types of forward primers designed based on the nucleotide difference at position 234. When DNAs of four Curcuma species were used as templates, PCR amplification with either of the two primers only generated a fragment of 912 base pairs (bp). However, when DNAs of the purple-cloud type of C. kwangsiensis and C. wenyujin were used, PCR amplifications with both primers unexpectedly generated the fragment, suggesting that these two were heterozygotes. The ARMS method for the trnK gene was also established using a mixture of four types of specific reverse primers designed on the basis of base substitutions and indels among six species, and common reverse and forward primers. C. phaeocaulis or the Chinese population of C. zedoaria, the Japanese population of C. zedoaria or the purple-cloud type of C. kwangsiensis, the pubescent type of C. kwangsiensis or C. wenyujin, and C. aromatica were found to show specific fragments of 730, 185, 527 or 528, and 641 or 642 bp, respectively. All species including C. longa also showed a common fragment of 897-904 bp. Using both ARMS methods, together with information on producing areas, the identification of Curcuma plants was achieved. Moreover, the ARMS method for the trnK gene was also useful for authentication of Curcuma drugs.     

Authentication of Curcuma species (Zingiberaceae) based on nuclear 18S rDNA and plastid trnK sequences

Curcuma drugs have been used discriminatingly for invigorating blood circulation, promoting digestion, and as a cholagogic in China. However, there is confusion about the drug's botanical origins and clinical uses because of morphological similarity of Curcuma plants and drugs. Comparative sequencing of the 18S rRNA gene in nuclear ribosomal DNA (rDNA) and trnK gene in chloroplast DNA (cpDNA) was carried out in order to examine interspecies phylogeny and to identify ultimately Curcuma species. A total of a hundred of accessions of eighteen species were analyzed. This resulted in an aligned matrix of 1810 bp for 18S rDNA and 2 800 bp for trnK. 18S rDNA sequence divergence within the ingroup ranged from 0-0.05%, trnK ranged from 0-0.19%. One base transversion-substituted site (from cytosine to thymine) was observed from the upstream of 18S rDNA at nucleotide position 234 in C. kwangsiensis and Japanese population of C. zedoaria which have separated genetic distance to other Curcuma taxa. Two noncoding regions embedded in trnK intron showed higher variability, including nucleotide substitutions, repeat insertion and deletions. Based on consensus of relationship, eighteen major lineages within Curcuma are recognized at the species level. The results suggest that Curcuma is monophyletic with 100% bootstrap support and sister to the genera Hedychium and Zingiber. The trnK sequences showed considerable variations between Curcuma species and thus were revealed as a promising candidate for barcoding of Curcuma species, which provide valuable characters for inferring relationship within species but are insufficient to resolve relationships among closely related taxa.     

Phylogenetic relationship in the genus Panax: inferred from chloroplast trnK gene and nuclear 18S rRNA gene sequences

Chloroplast trnK gene and nuclear 18S rRNA gene sequences of 13 Panax taxa, collected mainly from Sino-Japanese floristic region, were investigated in order to construct phylogenetic relationship and to assist taxonomic delimitation within this genus. The length of trnK gene sequence varied from 2537 bp to 2573 bp according to the taxa, whereas matK gene sequences, embedded in the intron of trnK gene, were of 1512 bp in all taxa. Species-specific trnK/ matK sequence provided much insight into phylogeny and taxonomy of this genus. 18S rRNA gene sequences were of 1808 or 1809 bps in length, only 9 types of 18S rRNA sequences were observed among 13 taxa. Parsimony and neighbor-joining analyses of the combined data sets of trnK-18S rRNA gene sequences yielded a well-resolved phylogeny within genus Panax, where three main clades were indicated. P. pseudoginseng and P. stipuleanatus formed a sister group located at a basal position in the phylogenetic tree, which suggested the relatively primitive position of these two species. Monophyly of P. ginseng, P. japonicus (Japan) and P. quinquefolius, which are distributed in northern parts of Asia or America, was well supported (Northern Clade). The remaining taxa distributed in southern parts of Asia formed a relatively large clade (Southern Clade). The taxonomic debated taxa traditionally treated as subspecies or varieties of P. japonicus or P. pseudoginseng showed various nucleotide sequences, but all fell into one cluster. It might suggest these taxa are differentiated from a common ancestor and are in a period of high variation, which is revealed not only on morphological appearance, but also on molecular divergence. By comparing trnK and 18S rRNA gene sequences among 13 Panax taxa, a set of valuable molecular evidences for identification of Ginseng drugs was obtained.     

Phylogenetic analysis based on 18S rRNA gene and matK gene sequences of Panax vietnamensis and five related species

Panax vietnamensis was discovered recently in Vietnam. Its bamboo-like rhizomes, called Vietnamese Ginseng, have attracted considerable attention because of their specific pharmacological activities. In order to define the taxonomic position of this new species and include it in the molecular authentication of Ginseng drugs, the 18S ribosomal RNA gene and matK gene sequences of P. vietnamensis were determined and compared with those of its related taxa, P. japonicus var. major and P. pseudo-ginseng subsp. himalaicus, besides previously reported P. ginseng, P. japonicus and P. quinquefolius. The 18S rRNA gene sequences were found to be 1809 bps in length. The sequence of P. vietnamensis was identical to that of P. quinquefolius, and presented one base substitution from those of both P. japonicus var. major and P. pseudo-ginseng subsp. himalaicus. The matK gene sequences of 6 taxa were found to be 1509 bps in length. The sequence of P. vietnamensis differed from those of P. japonicus var. major, P. pseudo-ginseng subsp. himalaicus, P. ginseng, P. japonicus and P. quinquefolius at 4, 5, 9, 9 and 10 nucleotide positions, respectively. The phylogenetic tree reconstructed by the combined 18S rRNA-matK gene analysis using the maximum parsimony method showed that P. vietnamensis was sympatric with other Panax species and had a close relationship with P. japonicus var. major and P. pseudo-ginseng subsp. himalaicus.     

6种川产姜黄属药用植物叶绿体trnK基因序列变异分析及其分子鉴定

目的建立6种川产姜黄属(Curcuma)药用植物快速简单的分子鉴定方法.方法采用叶绿体赖氨酸tRNA基因(trnK)测序与序列变异分析方法.结果 6种姜黄属药用植物(包括姜黄C. longa、莪术C. phaeocaulis、川郁金C. sichuanensis、川郁金C. chuanyujin、川黄姜C. chuanhuangjiang、川莪术C. chuanezhu)完整trnK基因长度在2699～2705 bp.序列可变区包括matK基因编码区和trnK外显子与matK内含子之间区域,共有6个单核苷酸多态性(SNPs)位点、1个9-bp的缺失重复序列和2个4-bp、14-bp插入重复序列.结论 trnK基因序列可变位点可以作为6种川产姜黄属药用植物快速简单的分子鉴定标记,并为它们之间种的归并提供了分子依据.     

Application of single-nucleotide polymorphism analysis of the trnK gene to the identification of Curcuma plants

We previously found that Curcuma plants and drugs derived from Curcuma longa, C. phaeocaulis, C. zedoaria, and C. aromatica could be identified by the nucleotide differences at two sites and the existence of a 4-base indel on trnK gene. In this paper, based on species-specific nucleotide sequences, the application of a new method, single-nucleotide polymorphism (SNP) analysis was investigated to identify Curcuma plants more conveniently. First, three types of reverse primer were synthesized in different lengths, 34 mer, 26 mer, and 30 mer, to anneal the template DNAs from each species at sites immediately upstream from substitution positions 177 and 645, and at the site including the 4-base insertion from 728 to 731, respectively. After single-base extension reaction of these primers using fluorescent-labeled ddNTPs and PCR products of the trnK gene region as template, the resulting products were detected using an ABI PRISM 310 Genetic Analyzer. The electrophoretogram showed three or two peaks at different positions depending on the 27 mer, 31 mer, and 35 mer product lengths. Each peak was derived from the incorporated fluorescent-labeled ddNMPs complementary to template nucleotides at positions 645, 724, and 177, respectively. C. phaeocaulis showed three peaks of ddCMP, ddAMP, and ddAMP. The other three species showed two peaks derived from 27 mer and 35 mer products: peaks of ddCMP and ddAMP in C. longa, those of ddCMP and ddTMP in C. zedoaria, and those of ddTMP and ddAMP in C. aromatica. Thus SNP analysis to identify four Curcuma plants was newly developed.     

DNA authentication of Plantago Herb based on nucleotide sequences of 18S-28S rRNA internal transcribed spacer region

Internal transcribed spacer (ITS) regions of nuclear ribosomal RNA gene were amplified from 23 plant- and herbarium specimens belonging to eight Plantago species (P. asiatica, P. depressa, P. major, P. erosa, P. hostifolia, P. camtschatica, P. virginica and P. lanceolata). Sequence comparison indicated that these Plantago species could be identified based on the sequence type of the ITS locus. Sequence analysis of the ITS regions amplified from the crude drug Plantago Herb obtained in the markets indicated that all the drugs from Japan were derived from P. asiatica whereas the samples obtained in China were originated from various Plantago species including P. asiatica, P. depressa, P. major and P. erosa.     

Genetic variation and identification of cultivated Fallopia multiflora and its wild relatives by using chloroplast matK and 18S rRNA gene sequences

FALLOPIA MULTIFLORA (Thunb.) Harald . has been widely and discriminatingly used in China for the study and treatment of anemia, swirl, deobstruent, pyrosis, insomnia, amnesia, atheroma and also for regulating immune functions. However, there is still confusion about the herbal drug's botanical origins and the phylogenetic relationship between the cultivars and the wild relatives. In order to develop an efficient method for identification, a molecular analysis was performed based on 18 S rRNA gene and partial MATK gene sequences. The 18 S rRNA gene sequences of F. MULTIFLORA were 1809 bp in length and were highly conserved, indicating that the cultivars and the wild F. MULTIFLORA have the same botanical origin. Based on our 18 S rRNA gene sequences analysis, F. MULTIFLORA could be easily distinguished at the DNA level from adulterants and some herbs with similar components. The MATK gene partial sequences were found to span 1271 bp. The phylogenetic relation of F. MULTIFLORA based on the MATK gene showed that all samples in this paper were divided into four clades. The sequences of the partial MATK gene had many permutations, which were related to the geographical distributions of the samples. MATK gene sequences provided valuable information for the identification of F. MULTIFLORA. New taxonomic information could be obtained to authenticate the botanical origin of the F. MULTIFLORA, the species and the medicines made of it.     

Molecular identification of "Chuanxiong" by nucleotide sequence and multiplex single base extension analysis on chloroplast trnK gene

Chloroplast trnK gene sequences of Cnidium officinale and Ligusticum chuanxiong were determined to establish an effective method for identifying Japanese Senkyu and Chinese Chuanxiong, the two which have the same drug name in Chinese characters, similar external feature, but different botanical origins. Three sites of nucleotide differences were found between these 2 species at positions 767,924 and 964 from upstream in trnK gene sequence, allowing molecular identification of the two plants and crude drugs. Further, three kinds of specific primers of 14 mer, 23 mer and 30 mer long were designed to detect these 3 sites of marker nucleotides. By using multiplex single base extension (MSBE) analysis with the 3 specific primers, C. officinale and L. chuanxiong could be distinguished clearly by the electrophoretograms, where 3 peaks with different color of ddTMP, ddCMP and ddTMP were observed in case of C. officinale and those of ddGMP, ddAMP and ddGMP in L. chuanxiong. Moreover, trnK gene sequence of "Dongxiong," a kind of Chuanxiong cultivated in Northeast China, suggested that its botanical origin was C. officinale.     

Genetic variation of Croton stellatopilosus Ohba based on non-coding DNA sequences of ITS, trnK and trnL-F regions

Croton stellatopilosus Ohba (Plau-noi), a well-known Thai medicinal plant, was investigated for its genetic variation by analyzing three DNA regions, one nuclear internal transcribed spacer (ITS) region and two chloroplast trnL-F intergenic spacer and trnK intron regions. The results of ITS sequencing from 30 leaf samples showed that there were two major genotypes of C. stellatopilosus which were designated as STEL Type A and B. In addition, various nucleotide additive sequences which had presumably arisen from these two groups were also found. These so-called "putative hybrids", interestingly, displayed trnK intron sequences identical to the STEL Type B but different from the Type A. For the trnL-F region, all the 30 samples showed identical sequences. Thus, it was suggested that in the hybridization of C. stellatopilosus, the Type A genotype acts as paternal parent whereas the Type B genotype acts as maternal parent. In addition, all C. stellatopilosus samples were analyzed for their plaunotol content using TLC densitometry. We found that the Type A genotype, hybrid group and Type B genotype had plaunotol content in the ranges 0.209-0.492, 0.319-0.896 and 0.442-1.000% (w/w) dry weight, respectively. The results indicated that there is a correlation between the plaunotol contents and non-coding DNA sequences of ITS, trnK and trnL-F regions of C. stellatopilosus.     

三七的18S rRNA,matK基因序列和HPLC化学指纹图谱分析研究

目的分析中药三七Panaxnotoginseng的18SrRNA和matK基因的分子特征和三七的化学指纹特征,为三七的正品药材基原鉴定提供分子和化学依据。方法采用PCR直接测序技术测定三七及其7种伪品的18SrRNA和matK基因部分核苷酸序列以及不同产地三七的DNA分子特征。利用HPLC的化学分析技术,明确产地对三七化学成分的影响,以及三七不同部位的化学指纹特征。结果(1)三七及其7种常见伪品的核糖体18SrRNA基因序列存在很大的差异。(2)不同产地的三七的核糖体18SrRNA和叶绿体matK基因序列特征完全一致,分别与GenBank上已报道的R1型(D85171)和M1型(AB027526)序列吻合。(3)不同产地的三七HPLC指纹图谱相似。(4)三七不同部位均具有其相对稳定的HPLC指纹特征,其中花、叶具有特有的指纹区,根、须根、剪口、筋条等不同商品规格的HPLC指纹图谱比较相似。结论基因序列标记能从分子水平定性分辨三七及其伪品的遗传背景差异,为中药品种标准化提供了先进可行、稳定可靠的分子标准;HPLC指纹图谱分析可以直观地为三七的化学成分定性,三七不同商品规格的特征性指纹有望成为以其为原材料的各种产品的质控标准,而三七不同部位(尤其是花和叶)的HPLC指纹图谱将有望成为制定三七花、三七叶新药用资源质控标准的依据。     

应用16SrRNA基因序列分析快速鉴定临床标本中的革兰氏阳性杆菌

目的探索一种快速鉴定临床标本中革兰氏阳性杆菌的方法。方法利用PCR技术扩增待检菌株的16SrRNA基因序列,通过分析待检菌株的16SrRNA基因序列对其进行鉴定。结果5株待检菌株的16SrRNA基因序列均成功扩增,其中4株的16SrRNA基因序列与基因库中已注册的核酸序列相似率达99．9％以上,将其鉴定到种的水平,1株的16SrRNA基因序列与基因库中雷弗森菌属的核酸序列相似率为97．09％,将其鉴定为雷弗森菌属。结论应用16SrRNA基因序列分析可快速、准确地鉴定临床标本中的革兰氏阳性杆菌。     

采挖期内不同月份对广西桂莪术挥发油的影响

目的 考察采挖期内不同月份对桂莪术主要成分的影响.方法 利用挥发油提取器提取,比较不同采收月份桂莪术挥发油含量;运用HPLC法测定不同采收月份中吉马酮的含量,色谱柱为C18柱(4.60×250mm,5μm),流动相为乙腈-水(67∶33),检测波长210nm,流速为1.0mL·min-1;柱温为35℃.结果 HT6K 10月份采挖的桂莪术挥发油含量最高,11月份桂莪术吉马酮含量最高.结论 采挖期内不同月份桂莪术挥发油和吉马酮含量差异明显.     

Application of 12S rRNA gene for the identification of animal-derived drugs

PURPOSE. Animal-derived drugs are the major source of biological products and traditional medicine, but they are often difficult to identify, causing confusion in the clinical application. Among these medicinal animals, a number of animal species are endangered, leading to the destruction of biodiversity. The identification of animal-derived drugs and their alternatives would be a first step toward biodiversity conservation and safe medication. Until now, no effective method for identifying animal-derived drugs has been demonstrated; DNA-based species identification presents a brand-new technique. METHODS. We designed primers to amplify a 523-bp fragment of 12S rRNA and generated sequences for 13 individuals within six medicinal animal species. We examined the efficiency of species recognition based on this sequence, and we also tested the taxonomic affiliations against the GenBank database. RESULTS. All the tested drugs were identified successfully, and a visible gap was found between the inter-specific and intra-specific variation. We further demonstrated the importance of data exploration in DNA-based species identification practice by examining the sequence characteristics of relative genera in GenBank. This region of the 12S rRNA gene had a 100% success rate of species recognition within the six medicinal animal species. CONCLUSIONS. We propose that the 12S rRNA locus might be universal for identifying animal-derived drugs and their adulterants. The development of 12S rRNA for indentifying animal-derived drugs that share a common gene target would contribute significantly to the clinical application of animal-derived drugs and the conservation of medicinal animal species. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.     

DNA sequencing analysis of ITS and 28S rRNA of Poria cocos

We determined the DNA sequences of the internal transcribed spacer 1 and 2 (ITS 1 and 2), the 5.8S rRNA gene and most of the 28S rRNA gene of Poria cocos for the first time, and conducted analysis of 20 samples including cultured mycelias and crude drug materials obtained from various localities and markets. Direct sequencing of the ITS 1 and 2 regions of the samples, except for four wild samples, showed that they had identical DNA sequences for ITS 1 and 2 with nucleotide lengths of 997 bps and 460 bps, respectively. By cloning, the four wild samples were found to have combined sequences of common ITS sequences with 1 or 2-base-pair insertions. Altogether both ITS 1 and 2 sequences were substantially longer than those of other fungal crude drugs such as Ganoderma lucidum and Polyporus umbellatus. Thus, Poria cocos could be distinguished from these crude drugs and fakes by comparing the nucleotide length of PCR products of ITS 1 and 2. Contrary to the basic homogeneity in ITS 1 and 2, three types (Group 1, 2, 3) of the 28S rRNA gene with distinctive differences in length and sequence were found. Furthermore, Group 1 could be divided into three subgroups depending on differences at nucleotide position 690. Products with different types of 28S rRNA gene were found in crude drugs from Yunnan and Anhui Provinces as well as the Korean Peninsula, suggesting that the locality of the crude drugs does not guarantee genetic uniformity. The result of DNA typing of Poria cocos may help discrimination of the quality of the crude drug by genotype.     

Characterization of medicinal Epimedium species by 5S rRNA gene spacer sequencing

Sequences of 5S rRNA gene spacer were used to identify Epimedium brevicornu Maxim., E. sagittatum (Sieb. et Zucc.) Maxim., E. wushanense T. S. Ying, E. pubescens Maxim., and E. koreanum Nakai. These species are listed as source plants of Chinese medicine 'Ying Yang Huo' in the Chinese Pharmacopoeia. The neighbor-joining method was used in a sequence analysis of Epimedium species. A position-specific nucleotide was found in the 5S rRNA gene spacer for E. pubescens, E. wushanense, and E. brevicornu. A 19-bp deletion was found for E. koreanum in the 5S rRNA gene spacer. E. koreanum was most divergent from the other four endemic Chinese species of Epimedium.     

国产姜黄药材质量的比较研究

目的综合评价国产市售姜黄药材质量。方法采用HPLC法和UV法测定17批姜黄产地或商品药材中姜黄素类化合物含量,并测定了挥发油、醇浸出物含量、灰分及酸不溶性灰分、水分等常规检验项目。结果姜黄药材中姜黄素类成分含量变化范围较大,但各单一指标成分(如:姜黄素、去甲氧基姜黄素、二去甲氧基姜黄素)含量的分布比较均匀;常规理化试验项目测定结果表明不同产地或市场商品姜黄药材的质量差异大。结论姜黄素类含量及挥发油等常规试验指标可用于姜黄药材的综合评价和化学质量标准化。     

Mutations in the 23S rRNA gene of clarithromycin-resistant Helicobacter pylori from Japan

The 23S rRNA gene in clinical isolates of Helicobacter pylori isolated between 1995 and 2004 from Japan was investigated and the relationship between mutations in this gene and clarithromycin susceptibility was studied. Among nine mutations that have previously been reported to confer clarithromycin resistance, an adenine-->guanine transition at position 2142 (A2142G) or 2143 (A2143G) was detected in all clarithromycin-resistant strains (n=67) but not in any clarithromycin-susceptible strains (n=17). Mutations at positions 2182, 2223, 2244 and 2288 have previously been reported to confer clarithromycin resistance in H. pylori isolates from Bangladesh, China and Brazil. However, these mutations were not associated with clarithromycin resistance in H. pylori isolates from Japan in this study. Other mutations at positions 2115, 2144 and 2711, which have also been reported to confer clarithromycin resistance in H. pylori from Sweden and Italy, were not detected in the strains in this study. Our results suggest that susceptibility to clarithromycin is predicted by detection of mutations at positions 2142 and 2143 of the 23S rRNA gene in H. pylori isolates in Japan.     

Detection of genetic homogeneity of Panax notoginseng cultivars by sequencing nuclear 18S rRNA and plastid matK genes

The nuclear 18S rRNA and chloroplast MATK genes of 18 samples of Panax notoginseng and its processed material Sanqi (Radix Notoginseng) were analyzed. The two genes, regardless of cultivar origin, were found to be identical to genotype R1 and M1, respectively, of the published sequences (GenBank accession no. D85171 and AB027526). This phenomenon implies that the species is highly conserved, which is probably caused by the use of the same strain in cultivation and the lack of active mutation in these two genes.     

Quality evaluation of medicinally-used Codonopsis species and Codonopsis Radix based on the contents of pyrrolidine alkaloids,phenylpropanoid and polyacetylenes

A comparative study of 56 specimens of three medicinally-used Codonopsis taxa collected from China and 54 commercial samples of Codonopsis Radix available in Chinese, Japanese and Korean markets was carried out by quantitative analysis of seven major components: codonopyrrolidium B (1), codonopyrrolidium A (2), tangshenoside I (3), cordifolioidyne B (4), lobetyolinin (5), lobetyolin (6) and lobetyol (7). The quantitative results, based on a well-established HPLC–DAD method, indicated that the contents of these seven compounds varied considerably among the samples, not only inter-species but also intra-species. C. pilosula and C. pilosula var. modesta showed similar chemical compositions, while C. tangshen differed considerably from these two in chemical composition. The results of principal component analysis (PCA) indicated that two main groups were classified; one group mainly included C. pilosula, C. pilosula var. modesta and the commercial samples derived from these two taxa, while the other group was composed of C. tangshen and its derived commercial samples. Compound 1 was the main component in the roots of C. pilosula and C. pilosula var. modesta, while 3 and 2 had relatively high contents in the roots of C. tangshen. Therefore, 3, 2 and 1 could be chemical markers to differentiate C. tangshen from C. pilosula and C. pilosula var. modesta.