[Cloning and functional analysis of flavanone synthase â ¡ from Dendrobium huoshanense].

Flavonoid C-glycosides are a class of natural products that are widely involved in plant defense responses and have diverse pharmacological activities. They are also important active ingredients of Dendrobium huoshanense. Flavanone synthase Ⅱ has been proven to be a key enzyme in the synthesis pathway of flavonoid C-glycosides in plants, and their catalytic product 2-hydroxyflavanone is the precursor compound for the synthesis of various reported flavonoid C-glycosides. In this study, based on the reported amino acid sequence of flavanone synthase Ⅱ, a flavanone synthase Ⅱ gene(DhuFNSⅡ) was screened and verified from the constructed D. huoshanense genome localization database. Functional validation of the enzyme showed that it could in vitro catalyze naringenin and pinocembrin to produce apigenin and chrysin, respectively. The open reading frame(ORF) of DhuFNSⅡ was 1 644 bp in length, encoding 547 amino acids. Subcellular localization showed that the protein was localized on the endoplasmic reticulum. RT-qPCR results showed that DhuFNSⅡ had the highest expression in stems, followed by leaves and roots. The expression levels of DhuFNSⅡ and other target genes in various tissues of D. huoshanense were significantly up-regulated after four kinds of abiotic stresses commonly encountered in the growth process, but the extent of up-regulation varied among treatment groups, with drought and cold stress having more significant effects on gene expression levels. Through the identification and functional analysis of DhuFNSⅡ, this study is expected to contribute to the elucidation of the molecular mechanism of the formation of quality metabolites of D. huoshanense, flavonoid C-glycosides, and provide a reference for its quality formation and scientific cultivation.

A chromosome-scale genome of Peucedanum praeruptorum provide insights into Apioideae evolution and medicinal ingredient biosynthesis.

Peucedanum praeruptorum Dunn, a traditional Chinese medicine rich in coumarin, belongs to the Apiaceae family. A high-quality assembled genome of P. praeruptorum is lacking, which has posed obstacles to functional identification and molecular evolution studies of genes associated with coumarin production. Here, a chromosome-scale reference genome of P. praeruptorum, an important medicinal and aromatic plant, was first sequenced and assembled using Oxford Nanopore Technologies and Hi-C sequencing. The final assembled genome size was 1.83 Gb, with a contig N50 of 11.12 Mb. The entire BUSCO evaluation and second-generation read comparability rates were 96.0 % and 99.31 %, respectively. Furthermore, 99.91 % of the genome was anchored to 11 pseudochromosomes. The comparative genomic study revealed the presence of 18,593 orthogroups, which included 476 species-specific orthogroups and 1211 expanded gene families. Two whole-genome duplication (WGD) events and one whole-genome triplication (WGT) event occurred in P. praeruptorum. In addition to the γ-WGT shared by core eudicots or most eudicots, the first WGD was shared by Apiales, while the most recent WGD was unique to Apiaceae. Our study demonstrated that WGD events that occurred in Apioideae highlighted the important role of tandem duplication in the biosynthesis of coumarins and terpenes in P. praeruptorum. Additionally, the expansion of the cytochrome P450 monooxygenase, O-methyltransferase, ATP-binding cassette (ABC) transporter, and terpene synthase families may be associated with the abundance of coumarins and terpenoids. Moreover, we identified >170 UDP-glucosyltransferase members that may be involved in the glycosylation post-modification of coumarins. Significant gene expansion was observed in the ABCG, ABCB, and ABCC subgroups of the ABC transporter family, potentially facilitating the transmembrane transport of coumarins after bolting. The P. praeruptorum genome provides valuable insights into the machinery of coumarin biosynthesis and enhances our understanding of Apiaceae evolution.

Chloroplast genome of Justicia procumbens: genomic features, comparative analysis, and phylogenetic relationships among Justicieae species.

Justicia procumbens L. is a traditional medicinal plant that is widely distributed in China. However, little is known about the genetic diversity and evolution of this genus, and no genomic studies have been carried out on J. procumbens previously. In this study, we aimed to assemble and annotate the first complete chloroplast genome (cpDNA) of J. procumbens and compare it with all previously published cpDNAs within the tribe Justicieae. Genome structure and comparative and phylogenetic analyses were performed. The 150,454 bp-long J. procumbens cpDNA has a circular and quadripartite structure consisting of a large single copy, a small single copy, and two inverted repeat regions. It contains 133 genes, of which 88 are protein-coding genes, 37 are tRNA genes, and eight are rRNA genes. Twenty-four simple sequence repeats (SSRs) and 81 repeat sequences were identified. Comparative analyses with other Justicieae species revealed that the non-coding regions of J. procumbens cpDNA showed greater variation than did the coding regions. Moreover, phylogenetic analysis based on 14 cpDNA sequences from Justicieae species showed that J. procumbens and J. flava were most closely related. This study provides valuable genetic information to support further research on the genetic diversity and evolutionary development of the tribe Justicieae.

Optimization of Three Extraction Methods and Their Effect on the Structure and Antioxidant Activity of Polysaccharides in Dendrobium huoshanense.

Dendrobium huoshanense is a famous edible and medicinal herb, and polysaccharides are the main bioactive component in it. In this study, response surface methodology (RSM) combined with a Box-Behnken design (BBD) was used to optimize the enzyme-assisted extraction (EAE), ultrasound-microwave-assisted extraction (UMAE), and hot water extraction (HWE) conditions and obtain the polysaccharides named DHP-E, DHP-UM, and DHP-H. The effects of different extraction methods on the physicochemical properties, structure characteristics, and bioactivity of polysaccharides were compared. The differential thermogravimetric curves indicated that DHP-E showed a broader temperature range during thermal degradation compared with DHP-UM and DHP-H. The SEM results showed that DHP-E displayed an irregular granular structure, but DHP-UM and DHP-H were sponge-like. The results of absolute molecular weight indicated that polysaccharides with higher molecular weight detected in DHP-H and DHP-UM did not appear in DHP-E due to enzymatic degradation. The monosaccharide composition showed that DHPs were all composed of Man, Glc, and Gal but with different proportions. Finally, the glycosidic bond types, which have a significant effect on bioactivity, were decoded with methylation analysis. The results showed that DHPs contained four glycosidic bond types, including Glcp-(1→, →4)-Manp-(1→, →4)-Glcp-(1→, and →4,6)-Manp-(1→ with different ratios. Furthermore, DHP-E exhibited better DPPH and ABTS radical scavenging activities. These findings could provide scientific foundations for selecting appropriate extraction methods to obtain desired bioactivities for applications in the pharmaceutical and functional food industries.

Dendrobium huoshanense Polysaccharide Improves High-Fat Diet Induced Liver Injury by Regulating the Gut-Liver Axis.

Dendrobium huoshanense is an important Traditional Chinese medicine that thickens the stomach and intestines. Its active ingredient Dendrobium huoshanense polysaccharide (DHP), was revealed to relieve the symptoms of liver injury. However, its mechanism of action remains poorly understood. This study aimed to investigate the mechanism of DHP in protecting the liver. The effects of DHP on lipid levels, liver function, and intestinal barrier function were investigated in mice with high-fat diet-induced liver damage. Changes in the gut flora and their metabolites were analyzed using 16S rRNA sequencing and metabolomics. The results showed that DHP reduced lipid levels, liver injury, and intestinal permeability. DHP altered the intestinal flora structure and increased the relative abundance of Bifidobacterium animalis and Clostridium disporicum. Furthermore, fecal metabolomics revealed that DHP altered fecal metabolites and significantly increased levels of gut-derived metabolites, spermidine, and indole, which have been reported to inhibit liver injury and improve lipid metabolism and the intestinal barrier. Correlation analysis showed that spermidine and indole levels were significantly negatively correlated with liver injury-related parameters and positively correlated with the intestinal species B. animalis enriched by DHP. Overall, this study confirmed that DHP prevented liver injury by regulating intestinal microbiota dysbiosis and fecal metabolites.

The potential roles of acid invertase family in Dendrobium huoshanense: Identification, evolution, and expression analyses under abiotic stress.

Dendrobium huoshanense, a traditional Chinese medicine prized for its horticultural and medicinal properties, thrives in an unfavorable climate and is exposed to several adverse environmental conditions. Acid invertase (AINV), a widely distributed enzyme that has been demonstrated to play a significant role in response to environmental stresses. However, the identification of the AINV gene family in D. huoshanense, the collinearity between relative species, and the expression pattern under external stress have yet to be resolved. We systematically retrieved the D. huoshanense genome and screened out four DhAINV genes, which were further classified into two subfamilies by the phylogenetic analysis. The evolutionary history of AINV genes in D. huoshanense was uncovered by comparative genomics investigations. The subcellular localization predicted that the DhVINV genes may be located in the vacuole, while the DhCWINV genes may be located in the cell wall. The exon/intron structures and conserved motifs of DhAINV genes were found to be highly conserved in two subclades. The conserved amino acids and catalytic motifs in DhAINV proteins were determined to be critical to their function. Notably, the cis-acting elements in all DhAINV genes were mainly relevant to abiotic stresses and light response. In addition, the expression profile coupled with qRT-PCR revealed the typical expression patterns of DhAINV in response to diverse abiotic stresses. Our findings could be beneficial to the characterization and further investigation of AINV functions in Dendrobium plants.

Genome sequencing-based transcriptomic analysis reveals novel genes in Peucedanum praeruptorum.

BACKGROUND: Peucedanum praeruptorum Dunn, a traditional Chinese herbal medicine, contains coumarin and volatile oil components that have clinical application value. However, early bolting often occurs in the medicinal materials of Apiaceae plants. The rhizomes of the medicinal parts are gradually lignified after bolting, resulting in a sharp decrease in the content of coumarins. At present, the link between coumarin biosynthesis and early bolting in P. praeruptorum has not been elucidated. RESULTS: Combining the genome sequencing and the previous transcriptome sequencing results, we reanalyzed the differential transcripts of P. praeruptorum before and after bolting. A total of 62,088 new transcripts were identified, of which 31,500 were unknown transcripts. Functional classification and annotation showed that many genes were involved in the regulation of transcription, defense response, and carbohydrate metabolic processes. The main domains are the pentatricopeptide repeat, protein kinase, RNA recognition motif, leucine-rich repeat, and ankyrin repeat domains, indicating their pivotal roles in protein modification and signal transduction. Gene structure analysis showed that skipped exon (SE) was the most dominant alternative splicing, followed by the alternative 3' splice site (A3SS) and the alternative 5' splice site (A5SS). Functional enrichment of differentially expressed genes showed that these differentially expressed genes mainly include transmembrane transporters, channel proteins, DNA-binding proteins, polysaccharide-binding proteins, etc. In addition, genes involved in peroxisome, hexose phosphate pathway, phosphatidylinositol signaling system, and inositol phosphate metabolism pathway were greatly enriched. A protein-protein interaction network analysis discoverd 1,457 pairs of proteins that interact with each other. The expression levels of six UbiA genes, three UGT genes, and four OMT genes were higher during the bolting stage. This observation suggests their potential involvement in the catalytic processes of prenylation, glycosylation, and methylation of coumarins, respectively. A total of 100 peroxidase (PRX) genes were identified being involved in lignin polymerization, but only nine PRX genes were highly expressed at the bolting stage. It is worth noting that 73 autophagy-related genes (ATGs) were first identified from the KEGG pathway-enriched genes. Some ATGs, such as BHQH00009837, BHQH00013830, and novel8944, had higher expression levels after bolting. CONCLUSIONS: Comparative transcriptome analysis and large-scale genome screening provide guidance and new opinions for the identification of bolting-related genes in P. praeruptorum.

Selection of Suitable Reference Genes for Gene Expression Normalization Studies in Dendrobium huoshanense.

Dendrobium huoshanense is a kind of precious herb with important medicinal and edible value in China, which is widely used in traditional Chinese medicine for various diseases. Recent studies have paid close attention to the genetic expression of the biosynthetic pathway of the main active components (polysaccharides, alkaloids, and flavonoids), and real-time polymerase chain reaction (qPCR) is one of the most widely used methods for doing so. However, so far, no reference gene selections have been reported in D. huoshanense. In this study, 15 reference gene candidates (GAPDH, eIF, EF-1α, PP2A, UBCE, RPL5, TBP, APT1, MDH, PTBP3, PEPC, CYP71, NCBP2, TIP41, and F-box) were selected and evaluated for their expression stability in D. huoshanense under various experimental conditions, including in different tissues (root, stem, and leaf), abiotic stresses (oxidative, drought, cold, and UV), and hormone treatment (methyl jasmonate) using three statistical programs (geNorm, NormFinder, and BestKeeper). Then, the RefFinder program was employed to comprehensively validate the stability of the selected reference genes. Finally, the expression profiles of the CESA and GMPP genes were further analyzed, and these results indicated that TBP, NCBP2, and CYP71 were the top three most stable reference genes after comprehensive comparison, which could be used as stable reference genes for normalizing the genes expression in D. huoshanense. This study described here provides the first data regarding on reference gene selection in D. huoshanense, which will be extremely beneficial for future research on the gene expression normalization in D. huoshanense.

The complete chloroplast genome sequence of Exochorda racemosa (Lindl.) Rehd.

Exochorda racemosa (Lindl.) Rehd. is a traditional medicinal herb widely distributed in China. Here, we reported the complete chloroplast genome sequence of E. racemosa. The chloroplast genome (160,398 bp) was composed of four regions, with a large single-copy (LSC, 88,458 bp) region, a small single-copy (SSC, 19,190 bp) region, and two inverted repeat (IR, 26,375 bp) regions. The overall GC content was 36.48%. A total of 131 genes were predicted with 86 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The phylogenetic analysis showed that E. racemosa had a close relationship with E. serratifolia.

The complete chloroplast genome of the medicinal plant Paederia foetida L.

Paederia foetida L. belonging to Rubiaceae family is a perennial medicinal herb widely distributed in India and China. The first complete chloroplast genome sequence of P. foetida was assembled and characterized in this study. The total chloroplast genome was 153,591 bp in length with 37.74% GC content, composed of a large single-copy (LSC) region of 83,677 bp, a small single-copy (SSC) region of 16,888 bp and a pair of inverted repeat (IR) regions of 26,513 bp. The whole chloroplast genome encoded 133 genes, including 88 protein-coding genes, 37 tRNA genes and 8 rRNA genes. Phylogenetic analysis of 30 chloroplast genomes strongly suggested that P. foetida was closely related to P. scandens.

Dendrobium huoshanense C.Z.Tang et S.J.Cheng: A Review of Its Traditional Uses, Phytochemistry, and Pharmacology.

Dendrobium huoshanense, a traditional medicinal and food homologous plant, belongs to the family Orchidaceae and has a long history of medicinal use. It is reported that the stem of D. huoshanense has a variety of bioactive ingredients such as polysaccharides, flavonoids, sesquiterpenes, phenols, etc. These bioactive ingredients make D. huoshanense remarkable for its pharmacological effects on anti-tumor, immunomodulation, hepatoprotective, antioxidant, and anticataract activities. In recent years, its rich pharmacological activities have attracted extensive attention. However, there is no systematic review focusing on the chemical compositions and pharmacological effects of D. huoshanense. Therefore, the present review aims to summarize current research on the chemical compositions and pharmacological activities of D. huoshanense. This study provides valuable references and promising ideas for further investigations of D. huoshanense.

Comparative Transcriptomics Unveil the Crucial Genes Involved in Coumarin Biosynthesis in Peucedanum praeruptorum Dunn.

Peucedanum praeruptorum Dunn is a commonly used traditional Chinese medicine that is abundant in furano- and dihydropyrano coumarins. When P. praeruptorum reaches the bolting stage, the roots gradually lignified, and the content of coumarins declines rapidly. Non-bolting has always been a decisive factor for harvesting the P. praeruptorum materials. To evaluate the amount of coumarin components in unbolted and bolted P. praeruptorum, the variations of praeruptorin A, praeruptorin B, praeruptorin E, peucedanocoumarin I, and peucedanocoumarin II were determined. Additionally, 336,505 transcripts were obtained from the comparative transcriptome data. Among them, a total of 1,573 differentially expressed genes were screened out. To identify the critical genes involved in coumarin biosynthesis, comparative transcriptomics coupled with co-expression associated analysis was conducted. Finally, coumarin biosynthesis-related eighteen candidate genes were selected for the validation of qPCR. Additionally, a phylogenetic tree and the expression profile of ATP-binding cassette (ABC) transporters were constructed. To clarify the main genes in the regulation of coumarin biosynthesis, the interaction network of the co-expression genes from thirteen modules was constructed. Current results exhibited the significant increment of praeruptorin A, praeruptorin B and praeruptorin E in the bolted P. praeruptorum. Although, peucedanocoumarin I and peucedanocoumarin II were slightly increased. Besides the content of coumarins, the essential genes involved in the coumarin biosynthesis also exhibited an overall downward trend after bolting. Three peroxidases (PRXs) involved in the production of lignin monomers had been demonstrated to be downregulated. PAL, C4H, HCT, COMT, CCoAOMT, and some ABC transporters were dramatically downregulated at the bolting stage. These results indicated that the downregulation of coumarin biosynthetic genes in the bolted P. praeruptorum ultimately reduced the formation of coumarins. However, the mechanism through which bolting indirectly affects the formation of coumarin still needs extra functional verification.

Sequencing of the complete chloroplast genome of Rubia yunnanensis Diels and its phylogenetic analysis.

Rubia yunnanensis Diels, an important medicinal herb, is mainly distributed in Yunnan province, Southwest China. In this study, the complete chloroplast genome of R. yunnanensis was successfully sequenced. The assembled chloroplast genome was 155,108 bp in length with an overall GC content of 36.98%, including a pair of inverted repeat (IR) regions (26,573 bp, each), respectively, a large single-copy (LSC) region (84,848 bp) and a small single-copy (SSC) region (17,114 bp). The genome contained 131 genes, comprising 85 protein-coding genes, 37 tRNA genes, eight rRNA genes, and one pseudogene. The phylogenetic analysis indicated that R. yunnanensis was closely related to R. cordifolia.

The Chloroplast Genome of Wild Saposhnikovia divaricata: Genomic Features, Comparative Analysis, and Phylogenetic Relationships.

Saposhnikovia divaricata, a well-known Chinese medicinal herb, is the sole species under the genus Saposhnikovia of the Apiaceae subfamily Apioideae Drude. However, information regarding its genetic diversity and evolution is still limited. In this study, the first complete chloroplast genome (cpDNA) of wild S. divaricata was generated using de novo sequencing technology. Similar to the characteristics of Ledebouriella seseloides, the 147,834 bp-long S. divaricata cpDNA contained a large single copy, a small single copy, and two inverted repeat regions. A total of 85 protein-coding, 8 ribosomal RNA, and 36 transfer RNA genes were identified. Compared with five other species, the non-coding regions in the S. divaricata cpDNA exhibited greater variation than the coding regions. Several repeat sequences were also discovered, namely, 33 forward, 14 reverse, 3 complement, and 49 microsatellite repeats. Furthermore, phylogenetic analysis using 47 cpDNA sequences of Apioideae members revealed that L. seseloides and S. divaricata clustered together with a 100% bootstrap value, thereby supporting the validity of renaming L. seseloides to S. divaricata at the genomic level. Notably, S. divaricata was most closely related to Libanotis buchtormensis, which contradicts previous reports. Therefore, these findings provide a valuable foundation for future studies on the genetic diversity and evolution of S. divaricata.

Comparative analysis of chemical constituents by HPLC-ESI-MSn and antioxidant activities of Dendrobium huoshanense and Dendrobium officinale.

Dendrobium huoshanense is a Chinese medicinal herb that has high quality and excellent efficacy. However, the chemical basis of its activity is still unclear. Of note, Dendrobium officinale is the most widely utilized among the Dendrobium species. Therefore, the current study systematically investigated the chemical constituents of methanolic extracts and different polar fractions of aqueous extracts from the two herbs by HPLC-ESI-MSn , and then compared in vitro antioxidant activities of their five different polar extracts. Consequently, 61 and 49 compounds were identified from D. huoshanense and D. officinale, respectively, of which 43 compounds were common to both species. In addition, 17 out of 22 different compounds were identified only in D. huoshanense. Moreover, the peak areas of some shared identical compounds of D. huoshanense were significantly larger than that of D. officinale. In vitro antioxidant evaluation results showed that the n-BuOH-soluble fraction of the two herbs exhibited remarkable antioxidant activities. Furthermore, the antioxidant activities of different fractions of D. huoshanense were separately superior to that of D. officinale, which may be attributed to its variable and high contents of flavonoids, bibenzyls and phenanthrenes. These results provide the evidence for the high quality and efficacy of D. huoshanense.

Rapid Identification of Peucedanum praeruptorum Dunn and Its Adulterants by Hand-Held Near-Infrared Spectroscopy.

BACKGROUND: Peucedanum praeruptorum Dunn (PPD) is a traditional Chinese medical herb of high medical and economic value. However, PPD is often adulterated by inexpensive plants. OBJECTIVE: In order to establish an integrated and straightforward methodology to identify adulterated PPD products, hand-held near-infrared spectroscopy (NIRS) combined with chemical pattern recognition techniques was employed. METHOD: The standard normal variate (SNV) was used to preprocess the original near-infrared spectra. Principal component analysis (PCA), linear discriminant analysis (LDA), and partial least-squares regression analysis (PLSDA) were used to construct the recognition models. RESULTS: PCA analysis could not correctly distinguish PPD from non-PPD. However, based on absorbance in the spectral region of 1405-2442 nm and SNV pretreatment, the accuracy of the LDA model was above 90% at identifying genuine PPD. Compared with the LDA method, the PLSDA model is more stable and reliable, and its model prediction accuracy was 93.4%. CONCLUSION: The combination of NIRS and chemometric methods based on a hand-held near-infrared spectrometer is an efficient, nondestructive, and reliable method for validating traditional Chinese medicine PPD. HIGHLIGHTS: The advanced method based on a hand-held near-infrared spectrometer can be used for rapid identification and quality evaluation of PPD in the field, medicinal material markets, and points of sale.

[Isolation of Fusarium and identification of its toxins from tuberous root of Pseudostellaria heterophylla].

Fusarium is the major pathogen of root rot of Pseudostellaria heterophylla. This study aims to explain the possible distribution of Fusarium species and the contamination of its toxin-chemotypes in tuberous root of P. heterophylla. A total of 89 strains of fungi were isolated from the tuberous root of P. heterophylla. Among them, 29 strains were identified as Fusarium by ITS2 sequence, accounting for 32.5%. They were identified as five species of F. avenaceum, F. tricinctum, F. fujikuroi, F. oxysporum, and F. graminearum based on ß-Tubulin and EF-1α genes. LC-MS/MS detected 18, 1, and 5 strains able to produce ZEN, DON, and T2, which accounted for 62.1%, 3.4%, and 17.2%, respectively. Strain JK3-3 can produce ZEN, DON, and T2, while strains BH1-4-1, BH6-5, and BH16-2 can produce ZEN and T2. PCR detected six key synthase genes of Tri1, Tri7, Tri8, Tri13, PKS14, and PKS13 in strain JK3-3, which synthesized three toxins of ZEN, DON, and T2. Four key synthase genes of Tri8, Tri13, PKS14, and PKS13 were detected in strains BH1-4-1, BH6-5, and BH16-2, which were responsible for the synthesis of ZEN and T2. The results showed that the key genes of toxin biosynthesis were highly correlated with the toxins produced by Fusarium, and the biosynthesis of toxin was strictly controlled by the genetic information of the strain. This study provides a data basis for the targeted prevention and control of exo-genous mycotoxins in P. heterophylla and a possibility for the development of PCR for rapid detection of toxin contamination.

The complete chloroplast genome of Arisaema bockii Engler and its phylogenetic analysis in the family Araceae.

Arisaema bockii Engler is a perennial herbaceous medicinal plant, which is widely distributed in many provinces in China such as Anhui, Jiangsu, and Zhejiang. In this study, the complete chloroplast genome sequence of A. bockii was assembled and characterized based on high-throughput sequencing data. The total length of chloroplast genome was 175,537 bp, including large single-copy (LSC) and small single-copy (SSC) regions of 98,870 bp and 23,345 bp, respectively, which were separated by a pair of 27,161 bp inverted repeat (IR) regions. The genome contained 129 genes, including 84 protein-coding genes, 36 tRNA genes, 8 rRNA genes, and one pseudogene. The overall GC content of the genome was 33.6%. A phylogenetic tree reconstructed by 30 chloroplast genomes revealed that A. bockii was mostly related to the same genus species A. ringens, A. franchetianum and A. erubescens. The work reported the first complete chloroplast genome of A. bockii, which may provide some useful information to the evolution of the family Araceae.

Sequencing and phylogenetic analysis of the complete chloroplast genome of Arisaema heterophyllum Blume.

Arisaema heterophyllum Blume is a perennial medicinal herb widely distributed in China, Korea and Japan. In this study, the complete chloroplast genome sequence of A. heterophyllum was assembled and characterized based on high-throughput sequencing data. The whole chloroplast genome is 170,610 bp in length and contains 95,485 bp large single-copy (LSC) and 22,605 bp small single-copy (SSC) regions separated by a pair of 26,260 bp inverted repeat (IR) regions. It contained a total of 129 genes, including 84 protein-coding genes, 37 tRNA genes, and 8 rRNA genes, with an overall GC content of 34.5%. A phylogenetic tree reconstructed by 30 chloroplast genomes reveals that A. heterophyllum is mostly related to the same genus A. ringens, A. franchetianum and A. erubescens. The complete chloroplast genome of A. heterophyllum was the firstly reported and deposited at GenBank under accession number MZ424448.

The antithrombotic activity of natural and synthetic coumarins.

Thrombosis, which seriously endangers human health and life, is the leading cause of morbidity and mortality globally. Antithrombotic drugs can interfere with the occurrence and development of thrombotic diseases and play an important role in the treatment of thrombotic diseases. However, unsatisfactory efficacy and serious adverse effects of existing antithrombotic drugs increase the research for new, efficient and safer drugs. Natural and synthetic coumarins have been shown to possess antithrombotic activity, namely, anticoagulation and antiplatelet aggregation. Especially, coumarin-based warfarin, phenprocoumon and cloricromen have long been used in clinical treatment of thrombosis. Coumarin with low toxicity is the privileged structure for developing novel antithrombotic drugs with multiple mechanisms of action. The present review aims to compile current research on the development of coumarins against thrombosis, emphasizing the relationship between their chemical structures and therapeutic effectiveness. It is intended to provide promising ideas for the discovery of novel coumarin derivatives with high antithrombotic activity.