Genus Dendrobium Research Articles

Mitochondrial genome insights into the spatio-temporal distribution and genetic diversity of Dendrobium hancockii Rolfe (Orchidaceae)

IntroductionWith its distinctive evolutionary rate and inheritance patterns separate from the nuclear genome, mitochondrial genome analysis has become a prominent focus of current research. Dendrobium hancockii Rolfe, a species of orchid with both medicinal and horticultural value, will benefit from the application of the fully assembled and annotated mitochondrial genome. This will aid in elucidating its phylogenetic relationships, comparative genomics, and population genetic diversity.MethodsBased on sequencing results from Illumina combined with PacBio and Nanopore, the mitochondrial genome map of D. hancockii was constructed. Comparative analysis was conducted from the perspectives of phylogeny across multiple species, selection pressure on protein-coding genes, and homologous segments. The population diversity of D. hancockii was analyzed using single nucleotide polymorphism (SNP) data from the mitochondrial genome and single-copy nuclear genes.Results and discussionThis research constructed a circular mitochondrial map for D. hancockii, spanning 523,952 bp, containing 40 unique protein-coding genes, 37 transfer RNA genes, and 4 ribosomal RNA genes. Comparative analysis of mitochondrial genes from 26 land plants revealed a conserved gene cluster, "rpl16-ccmFn-rps3-rps19," particularly within the Dendrobium genus. The mitochondrial genome of D. hancockii exhibits a lower point mutation rate but significant structural variation. Analysis of 103 resequencing samples identified 19,101 SNP sites, dividing D. hancockii into two major groups with limited gene flow between them, as supported by population diversity, genetic structure analysis, principal component analysis, and phylogenetic trees. The geographical distribution and genetic differentiation of D. hancockii into two major groups suggest a clear phytogeographical division, likely driven by ancient geological or climatic events. The close alignment of mitochondrial data with nuclear gene data highlights the potential of the mitochondrial genome for future studies on genetic evolution in this species.

Efficient Surface Sterilant for Establishment of Dendrobium in vitro Culture

Background: Most orchid species in the Dendrobium genus are epiphytic. Dendrobium orchid (Dendrobium nobile L.) var. Sonia is a non-woody epiphytic orchid that bears a beautiful purple-coloured flower and grows in soilless medium. Dendrobium can be propagated vegetatively through divisions or Keikis. But this propagation method is extremely slow. Micropropagation is most suitable method for multiplication of dendrobium orchids. Surface sterilization is an important step in the preparation of vigorous and viable explants in micropropagation. Most of the surface contaminants can be abolished by surface sterilization with a suitable sterilizing agent. The aim of the investigation is to present an effective disinfection method for the aseptic culture of Dendrobium var. Sonia by using nodal segments. Methods: In the present investigation, two sterilant were employed namely mercuric chloride (HgCl2) and sodium hypochlorite (NaOCl) at different concentrations and durations. A total of nine combinations were tried for treating nodal explants in this investigation during 2022-2023. Explants were surface sterilized with 70% ethanol for 5 minutes followed by 3 to 4 washes with sterile distilled water. Thereafter, the explants were subjected to different surface sterilization treatments to establish contamination free cultures. Result: The study revealed that among the 9 treatments, minimum contamination (30.40%) was recorded in 0.1% HgCl2 for 10 minutes which helps in the maximum establishment of healthy culture (69.60%). Whereas, the lowest result for establishment was found in autoclaved distilled water with maximum contamination (100%). Maximum explant mortality (20.80%) due to sterilant was observed in NaOCl (2%) for 20 minutes.

Systematic Characterization of Sesquiterpenes from Dendrobium nobile through Offline Two-Dimensional Chromatography Tandem Mass Spectrometry and Target Isolation.

Dendrobium nobile is a species of the genus Dendrobium that can be used as both a medicinal herb and healthy food. The sesquiterpenes in D. nobile have attracted extensive attention in recent years. In this study, Amide × RP offline two-dimensional chromatography separation tandem high-resolution mass spectrometry combined with GNPS (Global Natural Product Social Molecular Networking) was developed for the characterization of sesquiterpenes in D. nobile. After first-dimensional amide separation, the 70% ethanol extract of D. nobile was divided into 40 fractions, which were analyzed by second-dimensional reverse-phase system separation and LTQ-Orbitrap detection. The raw data was imported into the GNPS, resulting in the efficient clustering of similar substances. Finally, 594 sesquiterpene compounds were characterized, and 25 compounds were isolated based on molecular network analysis, including six new compounds. In vitro bioassays, the isolated compounds decreased NO production in the LPS-induced microglial BV-2 cell model and the content of MDA in PC12 cells, demonstrating neuroprotective activity. These findings unraveled the underlying material and provided valuable insights into the quality control of D. nobile.

Moscatilin, a potential therapeutic agent for cancer treatment: insights into molecular mechanisms and clinical prospects.

Moscatilin, a bibenzyl derivative from the Dendrobium genus, has been traditionally used in Chinese medicine. Recent studies suggest its potential as a powerful anticancer agent due to its diverse pharmacological properties.This review aims to consolidate current research on moscatilin's anticancer mechanisms, structure-activity relationships, and therapeutic potential to assess its viability for clinical use. A literature search was performed in PubMed/MedLine, Scopus, and Web of Science.The search focused on "cancer," "moscatilin," "anticancer," "bioactivity," "dendrobium," and "pharmacological properties." Relevant studies on molecular mechanisms, preclinical and clinical efficacy, and bioavailability were reviewed. Moscatilin exhibits significant anticancer effects in lung, breast, colorectal, and pancreatic cancers. It induces apoptosis via the JNK/SAPK pathway, inhibits cell proliferation, and suppresses metastasis. Structure-activity relationship studies reveal that phenolic groups and a two-carbon bridge are crucial for its efficacy. Additionally, moscatilin shows good bioavailability and a favorable safety profile, with low toxicity to healthy cells. Moscatilin demonstrates considerable potential as an anticancer agent, targeting multiple cancer progression pathways. Further clinical trials are essential to confirm its therapeutic efficacy and safety in humans.

Integrated metabolomic and transcriptomic analysis reveals variation in the metabolites of Dendrobium officinale, Dendrobium huoshanense, Dendrobium nobile.

Dendrobium is a perennial herb of the genus Dendrobium in the orchid family. Generally, Dendrobium officinale (TP) and Dendrobium huoshanense (HS) are both considered to have the function of yin-nourishing, while Dendrobium nobile (JC) has better efficacy of heat-clearing. However, because of the wide variety of Dendrobium species, the classification and clinical application of Dendrobium are often confused clearly distinguished in different medicinal uses. In order to compare the differentially accumulated metabolites (DAMs) and differentially expressed genes (DEGs) of the three Dendrobium. We selected TP, HS, and JC cultivated on stone for metabolomic and transcriptomic analyses between 2 and 3 years. The results showed that a total of 489 metabolites were obtained, including 72 were DAMs. The 72 DAMs were mainly enriched in metabolic pathways and biosynthesis of secondary metabolites. Transcriptome analysis results showed that 1,038 annotated DEGs were identified among the three Dendrobium species. The comprehensive analysis showed that the three Dendrobium differed in the distribution of the content of four major active components: flavonoids, amino acids, alkaloids, and sugars and alcohols, among which the DAMs and DEGs were mainly enriched in metabolic pathways and secondary metabolite biosynthesis. In this study, metabolomics and transcriptomics were utilized to compare the differences among the three species of Dendrobium, to provide theoretical references for future research and selection of different species of Dendrobium based on different medicinal uses, and to lay the foundation for further research on the biosynthesis of flavonoids in Dendrobium.

Comparative analysis of the mitochondrial genomes of four Dendrobium species (Orchidaceae) reveals heterogeneity in structure, synteny, intercellular gene transfer, and RNA editing.

The genus Dendrobium, part of the Orchidaceae family, encompasses species of significant medicinal, nutritional, and economic value. However, many Dendrobium species are threatened by environmental stresses, low seed germination rates, and overharvesting. Mitochondria generate the energy necessary for various plant life activities. Despite their importance, research on the mitochondrial genomes of Dendrobium species is currently limited. To address this gap, we performed a comprehensive genetic analysis of four Dendrobium species-D. flexicaule, D. nobile, D. officinale, and D. huoshanense-focusing on their mitochondrial and chloroplast genomes to elucidate their genetic architecture and support conservation efforts. We utilized advanced sequencing technologies, including Illumina for high-throughput sequencing and Nanopore for long-read sequencing capabilities. Our findings revealed the multichromosomal mitochondrial genome structures, with total lengths ranging from 596,506 bp to 772,523 bp. The mitochondrial genomes contained 265 functional genes, including 64-69 protein-coding genes, 23-28 tRNA genes, and 3 rRNA genes. We identified 647 simple sequence repeats (SSRs) and 352 tandem repeats, along with 440 instances of plastid-to-mitochondrial gene transfer. Additionally, we predicted 2,023 RNA editing sites within the mitochondrial protein-coding genes, predominantly characterized by cytosine-to-thymine transitions. Comparative analysis of mitochondrial DNA across the species highlighted 25 conserved genes, with evidence of positive selection in five genes: ccmFC, matR, mttB, rps2, and rps10. Phylogenetic assessments suggested a close sister relationship between D. nobile and D. huoshanense, and a similar proximity between D. officinale and D. flexicaule. This comprehensive genomic study provides a critical foundation for further exploration into the genetic mechanisms and biodiversity of Dendrobium species, contributing valuable insights for their conservation and sustainable utilization.

Constituents from Dendrobium aphyllum: Bibenzyls, furfurals, phenanthrenes, and phenylpropanoids and their antioxidant and anti-inflammatory potentials

Chemical investigation on the aqueous extract of Dendrobium aphyllum led to the isolation of thirty-one constituents with structures identified by analysis of the extensive spectroscopic data (1D/2D NMR, MS, UV, and ECD), including previously undescribed two bibenzyls, one furfural, and one phenolic acid, namely trigonopol D (1), trigonopol C (2), dendrofunan A (10), and 6-(4-hydroxy-3-methoxyphenyl)-3,6-dioxohexyl acetate (30), respectively, as well as twenty-seven known ones. Among them, there were one new natural product (11), seven compounds (6–7, 9, 12, 20, 28, 31) described from the genus Dendrobium for the first time, and fifteen compounds (8, 13–17, 19, 21–27, 29) isolated from D. aphyllum for the first time. Further, the antioxidant and anti-inflammatory potentials of fifteen compounds (4–5, 8, 11–12, 14–19, 22, 24, 26, and 29) with significant scavenging capacities against DPPH and hydroxyl radicals, and virtual docking activities inhibiting COX-2 and 5-LOX, respectively. Our study may draw the attention of medicinal plant taxonomists and supply potential quality markers for discrimination of D. aphyllum from other species in Dendrobium genus.

Effect of Melatonin on the Growth of Dendrobium officinale Protocorm-Like Bodies

Dendrobium officinale Kimura & Migo is a perennial herbaceous plant of the genus Dendrobium in the family of Orchidaceae with high medicinal value. Melatonin (MT) is an indole-like tryptamine with functions such as regulating plant growth and development. This experiment investigated the effects of different concentrations of MT on the growth and development of protocorms of D. officinale protocorm-like bodies (PLBs). The results showed that the changes in morphological indicators such as color, cluster size, and surface changes were more significant under 75 µM MT than those of 0 µM (CK), and the appearance of white on the PLB surface was expedited, which was more conducive to the proliferation of PLBs. MT treatment of 100 µM inhibited the differentiation of adventitious buds, and the contents of photosynthetic pigments, polysaccharides, and flavonoids were significantly increased. Moreover, as compared with CK, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in PLBs increased significantly, while the content of malondialdehyde (MDA) decreased gradually with 75 µM or less. In conclusion, a concentration of 75 µM melatonin can enhance the rapid propagation rate of D. officinale in vitro, providing insights into the effects of melatonin on the growth of tissue-cultured D. officinale seedlings.

Ecosystem services provided by orchids: a global analysis

Background: Orchids constitute one of the most diverse group of plants, they provide a large number of benefits to human society. Questions: What are the ecosystem services provided by orchids? Data description: We performed a systematic review based on 413 articles, of which 224 provide relevant information, focusing on publications by ecosystem service category, continent, genus, and quartile of journal. Study site and years studied: studies of orchids on all continents from 2000 to 2021. Methods: databases reviewed were BioOne, CONRICyT, EBSCO, EndNote, Google Scholar, JSTOR, Mendeley, ScienceDirect, Wiley library, as well as reviews of specialized books. Results: We found 75 articles on cultural services, followed by 66 on provisioning services, 64 on supporting and 19 on regulating services. The Epidendroideae subfamily was the most mentioned with 90.9 %, with the genus Dendrobium having the most mentions (39.13 %). Most of the orchid ecosystem service research was conducted on the American and Asian continents, where cultural and provisioning services were prevalent, respectively. Of all the publications, 54.7 % belong to quartile 1, and 2.4 % to quartile 4. Conclusions: This research contributes to our understanding of ecosystem services provided by orchids, which may allow us a more comprehensive understanding of how human society benefits from orchids, and what could be lost if these species are not conserved and used sustainably.

Comparative Analysis of Chloroplast Genome Variation and Evolutionary Analysis of the Endangered Species Dendrobium flexicaule and its Relative Species

Globally, the genus Dendrobium (Family: Orchidaceae) exhibits widespread distribution, predominantly occupying the tropical and subtropical areas of Asia. Although the chloroplast genomes (cpDNAs) of certain Dendrobium species have been documented, the evolutionary relationships among these species remain largely unexplored. In this pioneering investigation, a comprehensive analysis of the complete cpDNAs from Dendrobium species is presented, including Dendrobium flexicaule along with three closely related taxa (D. nobile, D. officinale, and D. huoshanense). The size of the novel complete cpDNAs ranged from 150,529 to 152,588 bp, and their cpDNA structure exhibits a unique quadrifoliate structure reminiscent of female quadrivalents, including large single copy, small single copy (SSC), and inverted repeat regions. A total of 175 simple sequence repeats were identified in the D. flexicaule cpDNA. A few pseudogenes of the NA(D)H dehydrogenase-like (NDH) genes were found in the annotated cpDNAs of the four Dendrobium species. Within the shared pseudogenes ndhF and ndhG, ndhF frequently undergoes mutations. Additionally, the phylogenetic analysis showed that D. flexicaule and D. scoriarum were close sister species. The research findings provide crucial genetic information for the molecular phylogenetic system of D. flexicaule.

BBS Gene Expression and Its Diversity in the Genus Dendrobium

Dendrobium officinale Kimura & Migo in the genus Dendrobium of Orchidaceae is an important medicinal plant that produces various bibenzyl and phenanthrene derivatives. In some orchids, these derivatives have been reported to increase with fungal infection. Bibenzyl biosynthesis is regulated by bibenzyl synthase (BBS). Although six genes of the BBS family have been registered from D. officinale, their gene regulation mechanisms are unclear. The infection of Dendrobium with mycorrhizal fungi also reportedly increases the expression of genes involved in biosynthesis; however, the effect of mycorrhizal fungi on bibenzyl production is unknown. The present study examined the effects of three mycorrhizal fungi isolated from D. officinale on BBS gene expression and bibenzyl production over time. One of the Tulasnellaceae operational taxonomic units induced BBS gene expression and increased two representative bibenzyls, gigantol and dendrophenol, at specific time points. Furthermore, 19 BBS sequences were cloned from 12 Dendrobium species, and a phylogenetic analysis was performed. The results indicated that repeated BBS gene duplication occurred during the evolution of the genus, and further duplication occurred after speciation. These results suggest that it is possible to optimize metabolite production by selecting suitable symbiotic fungi.

Octahydroindolizine alkaloid Homocrepidine A from Dendrobium crepidatum attenuate P. acnes-induced inflammatory in vitro and in vivo

Ethnopharmacological relevanceDendrobium crepidatum Lindl. ex Paxton is a perennial epiphyte of Dendrobium genus, distributed in southern China, and utilized as the traditional Chinese medicine “Shihu” in Yunnan Province. Due to its heat-clearing and detoxicating properties, it is formulated as the “XiaoCuoWan” as recorded in the China Pharmacopoeia, and specially used to treat chronic skin inflammatory diseases, such as acne. Aim of the studyThis research aimed to estimate impact of the octahydroindoline alkaloid Homocrepidine A (HCA), isolated from D. crepidatum, on acne inflammation using both human THP-1 cells and mouse models. Furthermore, the potential anti-inflammatory mechanism of HCA has been analyzed through molecular biology methods and computer simulation. Materials and methodsTHP-1 cells and mouse models induced by live Propionibacterium acnes (P. acnes) were employed to evaluate the anti-inflammatory properties of crude extract of D. crepidatum (DCE) and HCA. ELISA was utilized to detect the release of inflammatory cytokines in both cellular and murine ear tissues. RNAseq was used to screen the pathways associated with HCA-mediated inflammatory inhibition, while Western blot, RT-qPCR, and immunofluorescence were utilized to detect the expression of relevant proteins. Additionally, molecular docking simulations and cellular thermal shift assays were employed to confirm the target of HCA. ResultsOur research shows that DCE and HCA can effectively alleviate acne inflammation. HCA inhibits TLR2 expression by interacting with amino acid residues in the TIR domain of hTLR2, including Pro-681, Asn-688, Trp-684, and Ile-685. Moreover, HCA disrupts inflammatory signal transduction mediated by MAPK and NF-κB pathways through MyD88-dependent pathway. Additionally, HCA treatment facilitates Nrf2 nuclear translocation and upregulates HO-1 expression, thereby inhibiting NLRP3 inflammasomes activation. In vivo experiments further revealed that HCA markedly attenuated erythema and swelling caused by P. acnes in mice ears, while also decreasing the expression of pro-inflammatory cytokines IL-1β and IL-8. ConclusionsOur research highlights the protective effects of D. crepidatum and its bioactive compound HCA against acne inflammation, marking the first exploration of its potential in this context. The discoveries indicate that HCA treatment may represent a promising functional approach for acne therapy.

Chloroplast Genome-Wide Analysis Reveals New Single-Nucleotide Polymorphism Resources for the ARMS-qPCR Identification of Dendrobium brymerianum

Dendrobium brymerianum Rchb. f. is a species of orchid with pharmacological interest for its potential to inhibit the growth of human lung cancer cells. The identification of the Dendrobium species is a notable problem due to morphological similarities and the limitations of universal DNA barcodes. To overcome these difficulties, this study employed complete chloroplast (cp) genome sequences as useful resources for the identification of D. brymerianum. Based on Illumina sequencing, the complete cp genomes of five D. brymerianum individuals were assembled. These genomes were in the quadripartite structure, diverse in length between 151,832 and 152,189 bp, and comprised 126 genes. Moreover, significant differences were found in the Small Single-Copy (SSC) and Large Single-Copy (LSC) regions in comparison to the Inverted Repeat (IR) regions. This study recognized hotspot regions and simple sequence repeat (SSR) loci, providing valuable insights into genetic markers. The phylogenetic relationship of Dendrobium species was discovered, highlighting the need for more precise differentiation practices. To address this, ARMS-specific primers, mainly AAob1/AAob2, confirmed strong specificity, permitting the accurate identification of D. brymerianum from other species through ARMS-qPCR. Overall, this study of D. brymerianum chloroplast genomes has generated valuable data about sequence variations, phylogenetics, and mutation dynamics. These perceptions will be valuable in future research on population genetics, taxonomy, and species identification within the Dendrobium genus.

The Integration of the Metabolome and Transcriptome for Dendrobium nobile Lindl. in Response to Methyl Jasmonate

Dendrobium nobile Lindl., as an endangered medicinal plant within the genus Dendrobium, is widely distributed in southwestern China and has important ecological and economic value. There are a variety of metabolites with pharmacological activity in D. nobile. The alkaloids and polysaccharides contained within D. nobile are very important active components, which mainly have antiviral, anti-tumor, and immunity improvement effects. However, the changes in the compounds and functional genes of D. nobile induced by methyl jasmonate (MeJA) are not clearly understood. In this study, the metabolome and transcriptome of D. nobile were analyzed after exposure to MeJA. A total of 377 differential metabolites were obtained through data analysis, of which 15 were related to polysaccharide pathways and 35 were related to terpenoids and alkaloids pathways. Additionally, the transcriptome sequencing results identified 3256 differentially expressed genes that were discovered in 11 groups. Compared with the control group, 1346 unigenes were differentially expressed in the samples treated with MeJA for 14 days (TF14). Moreover, the expression levels of differentially expressed genes were also significant at different growth and development stages. According to GO and KEGG annotations, 189 and 99 candidate genes were identified as being involved in terpenoid biosynthesis and polysaccharide biosynthesis, respectively. In addition, the co-expression analysis indicated that 238 and 313 transcription factors (TFs) may contribute to the regulation of terpenoid and polysaccharide biosynthesis, respectively. Through a heat map analysis, fourteen terpenoid synthetase genes, twenty-three cytochrome P450 oxidase genes, eight methyltransferase genes, and six aminotransferase genes were identified that may be related to dendrobine biosynthesis. Among them, one sesquiterpene synthase gene was found to be highly expressed after the treatment with MeJA and was positively correlated with the content of dendrobine. This study provides important and valuable metabolomics and transcriptomic information for the further understanding of D. nobile at the metabolic and molecular levels and provides candidate genes and possible intermediate compounds for the dendrobine biosynthesis pathway, which lays a certain foundation for further research on and application of Dendrobium.

Comparative study on root anatomy of six species of Himalayan Dendrobium Swartz

Comprehensive knowledge of plant anatomy is an absolute necessity for accurately identifying taxa during their vegetative phase. Orchidaceae family has been extensively studied in the Himalayan region, with a focus on morphology and floristics. However, the anatomy of orchid roots has not been investigated in detail. This study examines the root anatomy of six Himalayan Dendrobium species (D. chrysanthum, D. densiflorum, D. longicornu, D. nobile, D. rotundatum, and D. transparens) using standard plant anatomy techniques. Qualitative and quantitative traits were observed and analysed, including the multi-layered velamen, stele and cortical tissue area, and number of xylem strands, which are distinct characteristics of genus Dendrobium. ANOVA and Tukey's test at 5% significance level were used to quantitatively examine cross-sections of the roots and identify significant differences. All six studied taxa possess velamen tissues with cells having spirally thickened walls, and a single-layered exodermis with cells of varying sizes. The cortex was multi-layered and contained parenchymatous water-storage cells, while a uniseriate endodermis with passage cells were observed. D. chrysanthum and D. rotundatum had xylem and phloem elements embedded in parenchymatous tissues, whereas D. densiflorum, D. longicornu, D. nobile, and D. transparens had xylem and phloem elements embedded in sclerenchymatous tissues. Cell sizes in different root tissues varied significantly. A dichotomous key based on the root anatomical traits for the identification of these Dendrobium species is provided. Future research is suggested to explore additional parameters and to conduct experiments to understand its anatomical response to epiphytism.

Gigantol exerts anti-lung cancer activity by inducing ferroptosis via SLC7A11-GPX4 axis

Gigantol, a naturally occurring dibenzyl compound derived from various orchid species within the Dendrobium genus, exhibits notable pharmacological activity. We found that gigantol has significant anti-lung cancer properties, both in vitro and in vivo, which it exerts through the induction of ferroptosis. Furthermore, we found gigantol's specific interaction with the subunit solute carrier family 7 member 11 (SLC7A11) within the cystine/glutamate antiporter system (system Xc−), leading to the inhibition of glutathione (GSH) synthesis. This, in turn, disrupts redox homeostasis. Additionally, gigantol hinders the uptake of extracellular cystine via lung cancer cells, resulting in reduced cellular levels of cysteine, a vital precursor in GSH synthesis. This reduction, in turn, leads to an increase in the levels of glutamate. Simultaneously, our study reveals that the decrease in GSH significantly inhibits the activity of glutathione peroxidase 4 (GPX4), a key enzyme within the antioxidant system. Remarkably, N-acetylcysteine, a cystine precursor, effectively reverses gigantol-induced ferroptosis in lung cancer cells. This provides further confirmation that the anti-lung cancer mechanism of gigantol is to induce ferroptosis of lung cancer cells by targeting the SLC7A11-GPX4 signaling axis. In conclusion, our study underscores gigantol's potential as a promising candidate drug for the treatment of patients with lung cancer in clinical practice.

Genetic similarity among Dendrobium species from Indonesia using RAPD markers

Abstract. Hartati S, Samanhudi, Cahyono O. 2023. Genetic similarity among Dendrobium species from Indonesia using RAPD markers. Biodiversitas 24: 5015-5021. Dendrobium genus orchids are one of the most popular commodities in the world due to their diverse range of flower sizes, shapes, and colors. To enhance plant breeding programs and genetic resources, it is necessary to obtain information on genetic similarity between orchids of the Dendrobium genus through molecular analysis techniques. Therefore, this study aimed to assess the genetic similarity among five Dendrobium species using molecular markers, specifically RAPD. The plant material used was obtained from five species of the Dendrobium spp, namely (i) Dendrobium mirbelianum; (ii) Dendrobium lamellatum, (iii) Dendrobium secundum, (iv) Dendrobium bracteosum, and (v) Dendrobium purpureum. The analysis was carried out to determine the genetic diversity of the Dendrobium orchids using RAPD markers. A total of five RAPD primers were used for amplification, namely OPD 8, OPA 7, OPA 13, OPB 12, and OPB 18. The scoring data were analyzed using NTSYS-pc (Numerical Taxonomy and Multivariate Analysis System) version 2.02 which produced data in the form of cluster dendrograms. The dendrogram that was constructed by Unweighted Pair Group Method Using Arithmetic Average (UPGMA) classified the five Dendrobium species into two main clusters. The results showed that there were two clusters, namely Cluster A consisting of D. mirbelianum, D. lamellatum, and D. secundum while Cluster B consisted of D. bracteosum and D. purpureum. Furthermore, the polymorphism of the five RAPD primers was very high, ranging from 91.6 to 100%, measuring 250-1900 bp. The coefficient of genetic similarity analyzed using the five RAPD primers ranged from 0.24 to 0.77. The species D. mirbelianum and D. lamellatum had a high coefficient of genetic similarity. Which can be discovered through parental selection in breeding program.

Uncovering the Phytochemical Profile, Antioxidant Potency, Anti-Inflammatory Effects, and Thrombolytic Activity in Dendrobium lindleyi Steud.

Background. Dendrobium genus has been used in traditional medicine to treat various illnesses. The study aims at examining the phytochemical, antioxidant, anti-inflammatory, and thrombolytic properties of the leaf, stem, and root of Dendrobium lindleyi Steud, and the relationship between phytochemicals and bioactivities is determined. Results. The qualitative screening found a variety of bioactive compounds, including alkaloids, coumarins, cardiac glycosides, glycosides, flavonoids, proteins, phenols, quinines, resins, steroids, saponins, tannins, and terpenoids, in varying amounts. The quantitative screening showed the highest concentration of alkaloids in the leaves (172.15 ± 1.22 mg/g), phenols in the root (203.55 ± 0.75 mg/g), flavonoids in the root (24.35 ± 0.42 mg/g), tannins in the leaves (105.06 ± 0.55 mg/g), and proteins in the root (194.12 ± 0.65 µg/ml). The root extract showed the highest antioxidant activity (IC50 = 58.24 µg/mL), the stem extract had the most increased thrombolytic activity (IC50 = 242.74 µg/mL), and the leaf extract had the most potent anti-inflammatory activity (IC50 = 61.79 µg/mL). Statistical analysis revealed a significant positive relationship (p = 0.05) between alkaloids (r = 0.96) and tannins (r = 0.9) with antioxidant, anti-inflammatory, and thrombolytic properties. Conclusion. The bioactivities of D. lindleyi, including antioxidant (root), thrombolytic (stem), and anti-inflammatory (leaf) activities, are linked to the phytochemicals detected in the screening.

Checklist of the genus Dendrobium Sw. (Orchidaceae) in Manipur, India

An enumeration of the genus Dendrobium Sw. (Orchidaceae) in Manipur, India was attempted. Literature review revealed the occurrence of 67 species under the genus from the state. The study was carried out through repeated field explorations in different natural forests of Manipur since 2012. Out of the total taxa reported from the state, only 42 species could be traced in the field. All these taxa are presented here with their flowering phenology and places of occurrence. Twenty-five species were untraceable in the field; however, nine species out of these 25 are represented by authentic herbarium specimens and supported by published documents. The remaining 16 species were reported only in literature, but no live plants or herbarium specimens were found. Out of the 42 species inventoried from the field, many taxa are under threat owing to habitat loss due to felling of trees, deforestation, and ‘jhum’ cultivation. So, there is an urgent need of conservation of those species through in situ and ex situ means for their sustenance. A photographic plate of some taxa is provided here which might be useful for their easy identification in the field and for taking care of their conservation. Large-scale uses of these species as cut flowers and indoor & outdoor plants may be practised through micropropagation and cultivation in nurseries which may help in revenue generation for the state.

Therapeutic potential of the chemical composition of Dendrobium nobile Lindl.

Dendrobium nobile Lindl. belongs to the genus Dendrobium of the orchid family and is a valuable herbal medicinal material. The information in this paper has been collected from the scientific literature databases including PubMed, Google Scholar, Web of Science, SciFinder, China National Knowledge Infrastructure, published books, Ph.D., and M.S. dissertations systematically in recent 20 years. "Dendrobium nobile Lindl.," "chemical composition," "pharmacological activities," and "diseases" were used as search terms to screen the literature. The collected chemical compositions are classified and summarized according to their different chemical structures, and the clinical disease treatment effects of Dendrobium nobile Lindl. are classified and summarized based on their pharmacological activities and different experimental disease models. Recent studies have revealed that Dendrobium nobile Lindl. contains chemical components such as alkaloids, bibenzyls, sesquiterpenes, phenanthrenes, and polysaccharides, and that its pharmacological activities are closely related to the chemical components, with pharmacological activities such as anti-tumor, anti-aging, immune enhancement, hypoglycemic, and anti-cataract. Currently, researchers are conducting extensive and detailed studies on Dendrobium nobile Lindl. and research experiments on its chemical constituents in the treatment of various clinical diseases. Therefore, the purpose of this paper is to review the chemical composition of Dendrobium nobile Lindl. and its experimental studies in the treatment of diseases and to provide a scientific reference for the future application of Dendrobium nobile Lindl. in the treatment of diseases.