Complete Chloroplast Genomes and Comparative Analysis of Sequences Evolution among Seven Aristolochia (Aristolochiaceae) Medicinal Species.

Aristolochiaceae, comprising about 600 species, is a unique plant family containing aristolochic acids (AAs). In this study, we sequenced seven species of Aristolochia, and retrieved eleven chloroplast (cp) genomes published for comparative genomics analysis and phylogenetic constructions. The results show that the cp genomes had a typical quadripartite structure with conserved genome arrangement and moderate divergence. The cp genomes range from 159,308 bp to 160,520 bp in length and have a similar GC content of 38.5%⁻38.9%. A total number of 113 genes were identified, including 79 protein-coding genes, 30 tRNAs and four rRNAs. Although genomic structure and size were highly conserved, the IR-SC boundary regions were variable between these seven cp genomes. The trnH-GUG genes, are one of major differences between the plastomes of the two subgenera Siphisia and Aristolochia. We analyzed the features of nucleotide substitutions, distribution of repeat sequences and simple sequences repeats (SSRs), positive selections in the cp genomes, and identified 16 hotspot regions for genomes divergence that could be utilized as potential markers for phylogeny reconstruction. Phylogenetic relationships of the family Aristolochiaceae inferred from the 18 cp genome sequences were consistent and robust, using maximum parsimony (MP), maximum likelihood (ML), and Bayesian analysis (BI) methods.

DNA barcoding of Aristolochia plants and development of species-specific multiplex PCR to aid HPTLC in ascertainment of Aristolochia herbal materials.

The anecdotal evidence is outstanding on the uses of Aristolochia plants as traditional medicines and dietary supplements in many regions of the world. However, herbal materials derived from Aristolochia species have been identified as potent human carcinogens since the first case of severe renal disease after ingesting these herbal preparations. Any products containing Aristolochia species have thus been banned on many continents, including Europe, America and Asia. Therefore, the development of a method to identify these herbs is critically needed for customer safety. The present study evaluated DNA barcoding of the rbcL, matK, ITS2 and trnH-psbA regions among eleven Aristolochia species collected in Thailand. Polymorphic sites were observed in all four DNA loci. Among those eleven Aristolochia species, three species (A. pierrei, A. tagala and A. pothieri) are used as herbal materials in Thai folk medicine, namely, in Thai "Krai-Krue". "Krai-Krue" herbs are interchangeably used as an admixture in Thai traditional remedies without specific knowledge of their identities. A species-specific multiplex PCR based on nucleotide polymorphisms in the ITS2 region was developed as an identification tool to differentiate these three Aristolochia species and to supplement the HPTLC pattern in clarifying the origins of herbal materials. The combination of multiplex PCR and HPTLC profiling achieves accurate herbal identification with the goal of protecting consumers from the health risks associated with product substitution and contamination.

Molecular Structure and Phylogenetic Analyses of Complete Chloroplast Genomes of Two Aristolochia Medicinal Species.

The family Aristolochiaceae, comprising about 600 species of eight genera, is a unique plant family containing aristolochic acids (AAs). The complete chloroplast genome sequences of Aristolochia debilis and Aristolochia contorta are reported here. The results show that the complete chloroplast genomes of A. debilis and A. contorta comprise circular 159,793 and 160,576 bp-long molecules, respectively and have typical quadripartite structures. The GC contents of both species were 38.3% each. A total of 131 genes were identified in each genome including 85 protein-coding genes, 37 tRNA genes, eight rRNA genes and one pseudogene (ycf1). The simple-sequence repeat sequences mainly comprise A/T mononucletide repeats. Phylogenetic analyses using maximum parsimony (MP) revealed that A. debilis and A. contorta had a close phylogenetic relationship with species of the family Piperaceae, as well as Laurales and Magnoliales. The data obtained in this study will be beneficial for further investigations on A. debilis and A. contorta from the aspect of evolution, and chloroplast genetic engineering.

Recalcitrant deep and shallow nodes in Aristolochia (Aristolochiaceae) illuminated using anchored hybrid enrichment.

Recalcitrant relationships are characterized by very short internodes that can be found among shallow and deep phylogenetic scales all over the tree of life. Adding large amounts of presumably informative sequences, while decreasing systematic error, has been suggested as a possible approach to increase phylogenetic resolution. The development of enrichment strategies, coupled with next generation sequencing, resulted in a cost-effective way to facilitate the reconstruction of recalcitrant relationships. By applying the anchored hybrid enrichment (AHE) genome partitioning strategy to Aristolochia using an universal angiosperm probe set, we obtained 231-233 out of 517 single or low copy nuclear loci originally contained in the enrichment kit, resulting in a total alignment length of 154,756bp to 160,150bp. Since Aristolochia (Piperales; magnoliids) is distantly related to any angiosperm species whose genome has been used for the plant AHE probe design (Amborella trichopoda being the closest), it serves as a proof of universality for this probe set. Aristolochia comprises approximately 500 species grouped in several clades (OTUs), whose relationships to each other are partially unknown. Previous phylogenetic studies have shown that these lineages branched deep in time and in quick succession, seen as short-deep internodes. Short-shallow internodes are also characteristic of some Aristolochia lineages such as Aristolochia subsection Pentandrae, a clade of presumably recent diversification. This subsection is here included to test the performance of AHE at species level. Filtering and subsampling loci using the phylogenetic informativeness method resolves several recalcitrant phylogenetic relationships within Aristolochia. By assuming different ploidy levels during bioinformatics processing of raw data, first hints are obtained that polyploidization contributed to the evolution of Aristolochia. Phylogenetic results are discussed in the light of current systematics and morphology.

[Molecular identification of aucklandiae radix, vladimiriae radix, inulae radix, aristolochiae radix and kadsurae radix using ITS2 barcode].

In order to identify Aucklandiae Radix, Vladimiriae Radix, Inulae Radix, Aristolochiae Radix and Kadsurae Radix using ITS2 barcodes, genomic DNA from sixty samples was extracted and the ITS2 (internal transcribed spacer) regions were amplified and sequenced. The genetic distances were computed using MEGA 5.0 in accordance with the kimura 2-parameter (K2P) model and the neighbor-joining (NJ) phylogenetic tree was constructed. The results indicated that for Aucklandiae Radix (Aucklandia lappa), Vladimiriae Radix (Vladimiria souliei and V. souliei var. cinerea), Inulae Radix (Inula helenium), Aristolochiae Radix (Aristolochia debilis) and Kadsurae Radix (Kadsura longipedunculata), the intra-specific variation was smaller than inter-specific one. There are 162 variable sites among 272 bp after alignment of all ITS2 sequence haplotypes. For each species, the intra-specific genetic distances were also smaller than inter-specific one. Furthermore, the NJ tree strongly supported that Aucklandiae Radix, Vladimiriae Radix, Inulae Radix, Aristolochiae Radix and Kadsurae Radix can be differentiated. At the same time, V. souliei (Dolomiaea souliei) and V. souliei var. cinerea( D. souliei var. cinerea) belonging to Vladimiriae Radix were clearly identified. In conclusion, ITS2 barcode could be used to identify Aucklandiae Radix, Vladimiriae Radix, Inulae Radix, Aristolochiae Radix and Kadsurae Radix. Our study may provide a scientific foundation for clinical safe use of the traditional Chinese medicines.

Identification of Baiying (Herba Solani Lyrati) commodity and its toxic substitute Xungufeng (Herba Aristolochiae Mollissimae) using DNA barcoding and chemical profiling techniques.

Baiying derived from Solanum lyratum Hance is a commonly consumed natural product for ethnomedical treatment of cancer. One of the substitutes present in the market is a carcinogenic aristolochic acids-containing herb Xungufeng derived from Aristolochia mollissima Thunb. The purpose of this study is to establish DNA barcodes, thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and cytotoxicity assay to differentiate Baiying from Xungufeng. A total of 30 DNA sequences from five DNA barcodes (ITS, matK, rbcL, trnH-psbA and trnL-trnF) were generated to differentiate S. lyratum from A. mollissima and authenticate ten samples of Baiying and Xungufeng commodities. Using aristolochic acids as standard markers, TLC and HPLC analyses also successfully authenticated these commodities. In vitro cytotoxicity assay using HEK-293 and Vero cells demonstrated that Xungufeng was significantly more toxic than Baiying. This is the first study applying an integrated molecular, chemical and biological approach to differentiate traditional Chinese medicine from Aristolochia adulterant.

[Study on LC-MS fingerprint for quality assessment of Aristolochia manshuriensis with chemical pattern recognition].

OBJECTIVE: To analyze LC-MS fingerprints of Aristolochia manshuriensis for quality assessment with two different chemical pattern recognition models. METHOD: LC-MS fingerprints of A. manshuriensis were established from 24 batches of samples from different habitats. SIMCA and Clustering analysis were used to compare the parameters of the 29 common peaks. RESULT: Two methods had good consistency, while they reflected the inherent sample information from different perspectives, respectively. CONCLUSION: Modern equipment analysis technology and multivariable chemical pattern recognition would be an efficient way for quality control and variety identification of A. manshuriensis.

Classification of Aristolochia species based on GC-MS and chemometric analyses of essential oils.

Essential oils were obtained from roots of 10 Aristolochia species by hydrodistillation and analysed by GC-MS. A total of 75 compounds were identified in the analysed oils. Multivariate analyses of the chemical constituents of the roots enabled classification of the species into four morphological groups. These forms of analysis represent an aid in identification of further specimens belonging to these species.

Molecular evolution of the petal and stamen identity genes, APETALA3 and PISTILLATA, after petal loss in the Piperales.

Organ loss is an evolutionary phenomenon commonly observed in all kinds of multicellular organisms. Across the angiosperms, petals have been lost several times over the course of their diversification. We examined the evolution of petal and stamen identity genes in the Piperales, a basal lineage of angiosperms that includes the perianthless (with no petals or sepals) families Piperaceae and Saururaceae as well as the Aristolochiaceae, which exhibit a well-developed perianth. Here, we provide evidence for relaxation of selection on the putative petal and stamen identity genes, homologs of APETALA3 and PISTILLATA, following the loss of petals in the Piperales. Our results are particularly interesting as the B-class genes are not only responsible for the production of petals but are also central to stamen identity, the male reproductive organs that show no modification in these plants. Relaxed purifying selection after the loss of only one of these organs suggests that there has been dissociation of the functional roles of these genes in the Piperales.

Complexities of the herbal nomenclature system in traditional Chinese medicine (TCM): lessons learned from the misuse of Aristolochia-related species and the importance of the pharmaceutical name during botanical drug product development.

Herbs used in traditional Chinese medicine (TCM) have diverse cultural/historical backgrounds and are described based on complex nomenclature systems. Using the family Aristolochiaceae as an example, at least three categories of nomenclature could be identified: (1) one-to-one (one plant part from one species): the herb guan mutong refers to the root of Aristolochia manshuriensis; (2) multiple-to-one (multiple plant parts from the same species serve as different herbs): three herbs, madouling, qingmuxiang and tianxianteng, derived respectively from the fruit, root and stem of Aristolochia debilis; and (3) one-to-multiple (one herb refers to multiple species): the herb fangji refers to the root of either Aristolochia fangchi, Stephania tetrandra or Cocculus trilobus; in this case, the first belongs to a different family (Aristolochiaceae) than the latter two (Menispermaceae), and only the first contains aristolochic acid (AA), as demonstrated by independent analytical data provided in this article. Further, mutong (Akebia quinata) is allowed in TCM herbal medicine practice to be substituted with either guan mutong (Aristolochia manshuriensis) or chuan mutong (Clematis armandii); and mu fangji (Cocculus trilobus) by guang fanchi (Aristolochia fangchi) or hanzhong fangji (Aristolochia heterophylla), thereby increasing the risk of exposing renotoxic AA-containing Aristolochia species to patients. To avoid these and other confusions, we wish to emphasize the importance of a pharmaceutical name, which defines the species name, the plant part, and sometimes the special process performed on the herb, including cultivating conditions. The pharmaceutical name as referred to in this article is defined, and is limited to those botanicals that are intended to be used as drug. It is hoped that by following the pharmaceutical name, toxic herbs can be effectively identified and substitution or adulteration avoided.

Genetical identification of Akebia and Aristolochia species by using Pyrosequencing.

This study was performed to determine if Akebia and Aristolochia species (Akebia quinata Decaisne and Aristolochia manshuriensis Kom.) could be identified by genetic analysis of Pyrosequencing method, which is used to assess genetic variation. The Pyrosequencing results of Akebia and Aristolochia species showed different patterns. The Pyrosequencing analysis of A. quinata Decaisne was very different compared with that of A. manshuriensis Kom. Pyrosequencing analyses might be able to identify the Akebia and Aristolochia species.

[LC-MS analysis of three kinds of Mutong medicinal materials].

Three kinds of Mutong medicinal materials (Lardizabalaceae, Ranunculaceae, Aristolochiaceae) were analyzed qualitatively by LC-MS. The results show Mutong of Lardizabalaceae and Mutong of Ranunculaceae have more the same chemical constituents, and Mutong of Aristolochiaceae has less the same constituents with them. These results are consistent with their medicinal properties and explain the similarity and difference in medicinal properties from chemical basis.

Toxicity of the Chinese herb mu tong (Aristolochia manshuriensis). What history tells us.

Plant sources of some traditional Chinese herbs may have changed over time. History records of herbal toxicity should be viewed critically when different plants might have been used under the same name in earlier eras. The current main source of the Chinese herb Mu Tong is Aristolochia manshuriensis. Examination of classical Chinese herbal literature revealed that until the mid 17th century the original source plants of Mu Tong had been several Akebia species. From the 17th century until the early 20th century Clematis species were the main source of Mu Tong. A manshuriensis has only been widely used since the 1950s. Renal failure due to ingestion of large doses of A. manshuriensis has been reported in China and other countries while no such toxicity has been recorded in traditional Chinese herbal texts. Documentation of traditional Chinese herbal literature should help to ensure the safe use of Chinese herbs.