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Dendrobium species, which are perennial herbs widely distributed in tropical and subtropical regions, are notable for their therapeutic properties attributed to various bioactive compounds, including dendrobine-type sesquiterpenoid alkaloids (DTSAs). The objective of this review article is to provide a comprehensive overview of recent advances in the biosynthesis of DTSAs, including their extraction from Dendrobium species and endophytes, elucidation of associated genes through genomic and transcriptomic sequencing in both Dendrobium spp. and endophytes, exploration of the biosynthetic pathways of DTSAs, and drawing conclusions and outlining future perspectives in this field. Alkaloids, predominantly nitrogen-containing compounds found in medicinal orchids, include over 140 types discovered across more than 50 species. DTSAs, identified in 37 picrotoxane alkaloids, have a distinctive five-membered nitrogen heterocyclic ring. This review highlights endophytic fungi as alternative sources of DTSAs, emphasizing their potential in pharmaceutical applications when plant-derived compounds are scarce or complex. Genomic and transcriptomic sequencing of Dendrobium spp. and their endophytes has identified key genes involved in DTSAs biosynthesis, elucidating pathways such as the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways. Genes encoding enzymes, such as acetyl-CoA C-acetyltransferase and diphosphomevalonate decarboxylase, are positively associated with dendrobine production. Despite significant advancements, the complexity of terpenoid biosynthesis in different subcellular compartments remains a challenge. Future research should focus on leveraging high-quality genomic data and omics technologies to further understand and manipulate the biosynthetic pathways of DTSAs and enhance their medicinal use. [ABSTRACT FROM AUTHOR]

Plant-microbe interactions are pivotal for ecosystem dynamics and sustainable agriculture, and are influenced by various factors, such as host characteristics, environmental conditions, and human activities. Omics technologies, including genomics, transcriptomics, proteomics, and metabolomics, have revolutionized our understanding of these interactions. Genomics elucidates key genes, transcriptomics reveals gene expression dynamics, proteomics identifies essential proteins, and metabolomics profiles small molecules, thereby oering a holistic perspective. This review synthesizes diverse microbial-plant interactions, showcasing the application of omics in understanding mechanisms, such as nitrogen fixation, systemic resistance induction, mycorrhizal association, and pathogen-host interactions. Despite the challenges of data integration and ethical considerations, omics approaches promise advancements in precision intervention and resilient agricultural practices. Future research should address data integration challenges, enhance omics technology resolution, explore epigenomics, and understand plant-microbe dynamics under diverse conditions. In conclusion, omics technologies hold immense promise for optimizing agricultural strategies and fortifying resilient plant-microbe alliances, paving the way for sustainable agriculture and environmental stewardship. [ABSTRACT FROM AUTHOR]

Bulbil is an important asexual reproductive structure of bulbil plants. It mainly grows in leaf axils, leaf forks, tubers and the upper and near ground ends of flower stems of plants. They play a significant role in the reproduction of numerous herbaceous plant species by serving as agents of plant propagation, energy reserves, and survival mechanisms in adverse environmental conditions. Despite extensive research on bulbil-plants regarding their resources, development mechanisms, and utilisation, a comprehensive review of bulbil is lacking, hindering progress in exploiting bulbil resources. This paper provides a systematic overview of bulbil research, including bulbil-plant resources, identification of development stages and maturity of bulbils, cellular and molecular mechanisms of bulbil development, factors influencing bulbil development, gene research related to bulbil development, multi-bulbil phenomenon and its significance, medicinal value of bulbils, breeding value of bulbils, and the application of plant tissue culture technology in bulbil production. The application value of the Temporary Immersion Bioreactor System (TIBS) and Terahertz (THz) in bulbil breeding is also discussed, offering a comprehensive blueprint for further bulbil resource development. Additionally, additive, seven areas that require attention are proposed: (1) Utilization of modern network technologies, such as plant recognition apps or websites, to collect and identify bulbous plant resources efficiently and extensively; (2) Further research on cell and tissue structures that influence bulb cell development; (3) Investigation of the network regulatory relationship between genes, proteins, metabolites, and epigenetics in bulbil development; (4) Exploration of the potential utilization value of multiple sprouts, including medicinal, ecological, and horticultural applications; (5) Innovation and optimization of the plant tissue culture system for bulbils; (6) Comprehensive application research of TIBS for large-scale expansion of bulbil production; (7) To find out the common share genetics between bulbils and flowers. [ABSTRACT FROM AUTHOR]

Introduction: Dendrobine, a valuable alkaloid found in Dendrobium nobile, possesses significant pharmaceutical potential. Methods: In this study, we explored innovative approaches to enhance dendrobine production by utilizing endophytic fungi in a Temporary Immersion Bioreactor System (TIBS, Nanjing BioFunction Co. Ltd., China) and traditional test bottles. Dendrobine was unequivocally identified and characterised in D. nobile co-culture seedlings through UHPLC analysis and LC-MS qTOF analysis, supported by reference standards. Results: The CGTB (control group) and EGTB (experimental group) 12-monthold D. nobile seedlings exhibited similar peak retention times at 7.6±0.1 minutes, with dendrobine identified as C16H25NO2 (molecular weight 264.195). The EGTB, co-cultured with Trichoderma longibrachiatum (MD33), displayed a 2.6-fold dendrobine increase (1804.23 ng/ml) compared to the CGTB (685.95 ng/ml). Furthermore, a bioanalytical approach was applied to investigate the monoculture of T. longibrachiatum MD33 with or without D. nobile seedlings in test bottles. The newly developed UHPLC-MS method allowed for dendrobine identification at a retention time of 7.6±0.1 minutes for control and 7.6±0.1 minutes for co-culture. Additionally, we explored TIBS to enhance dendrobine production. Co-culturing D. nobile seedlings with Trichoderma longibrachiatum (MD33) in the TIBS system led to a substantial 9.7-fold dendrobine increase (4415.77 ng/ml) compared to the control (454.01 ng/ml) after just 7 days. The comparative analysis of dendrobine concentration between EGTB and EGTIBS highlighted the remarkable potential of TIBS for optimizing dendrobine production. Future research may focus on scaling up the TIBS approach for commercial dendrobine production and investigating the underlying mechanisms for enhanced dendrobine biosynthesis in D. nobile. The structural elucidation of dendrobine was achieved through ¹H and 13C NMR spectroscopy, revealing a complex array of proton environments and distinct carbon environments, providing essential insights for the comprehensive characterization of the compound. Discussion: These findings hold promise for pharmaceutical and industrial applications of dendrobine and underline the role of endophytic fungi in enhancing secondary metabolite production in medicinal plants. [ABSTRACT FROM AUTHOR]

This review aims to elucidate the intricate effects and mechanisms of terahertz (THz) wave stress on Pinellia ternata, providing valuable insights into plant responses. The primary objective is to highlight the imperative for future research dedicated to comprehending THz wave impacts across plant structures, with a specific focus on the molecular intricacies governing root system structure and function, from shoots to roots. Notably, this review highlights the accelerated plant growth induced by THz waves, especially in conjunction with other environmental stressors, and the subsequent alterations in cellular homeostasis, resulting in the generation of reactive oxygen species (ROS) and an increase in brassinosteroids. Brassinosteroids are explored for their dual role as toxic by‐products of stress metabolism and vital signal transduction molecules in plant responses to abiotic stresses. The paper further investigates the spatio‐temporal regulation and long‐distance transport of phytohormones, including growth hormone, cytokinin, and abscisic acid (ABA), which significantly influence the growth and development of P. ternata under THz wave stress. With a comprehensive review of Reactive oxygen species (ROS) and Brassinosteroid Insensitive (BRI) homeostasis and signalling under THz wave stress, the article elucidates the current understanding of BRI involvement in stress perception, stress signalling, and domestication response regulation. Additionally, it underscores the importance of spatio‐temporal regulation and long‐distance transport of key plant hormones, such as growth hormone, cytokinin, and ABA, in determining root growth and development under THz wave stress. The study of how plants perceive and respond to environmental stresses holds fundamental biological significance, and enhancing plant stress tolerance is crucial for promoting sustainable agricultural practices and mitigating the environmental burdens associated with low‐tolerance crop cultivation. [ABSTRACT FROM AUTHOR]

Pinellia ternata (Thunb.) Breit. (Araceae), a significant medicinal plant, has been used to treat various diseases for centuries. Terahertz radiation (THZ) is located between microwaves and infrared rays on the electromagnetic spectrum. THZ possesses low single-photon energy and a spectral fingerprint, but its effects on plant growth have not yet been investigated. The study's primary objective was to examine the transcriptome and metabolome databases of the SY line to provide a new perspective for identifying genes associated with resistance and growth promotion and comprehending the underlying molecular mechanism. Variations in the biological characteristics of P. ternata grown under control and experimental conditions were analyzed to determine the effect of THZ. Compared with the control group, phenotypic variables such as leaf length, petiole length, number of leaves, leaf petiole diameter, and proliferation coefficient exhibited significant differences. P. ternata response to THZ was analyzed regarding the effects of various coercions on root exudation. The experimental group contained considerably more sugar alcohol than the control group. The transcriptome analysis revealed 1,695 differentially expressed genes (DEGs), including 509 upregulated and 1,186 downregulated genes. In the KEGG-enriched plant hormone signaling pathway, there were 19 differentially expressed genes, 13 of which were downregulated and six of which were upregulated. In the metabolomic analysis, approximately 416 metabolites were uncovered. There were 112 DEMs that were downregulated, whereas 148 were upregulated. The P. ternata leaves displayed significant differences in phytohormone metabolites, specifically in brassinolide (BR) and abscisic acid (ABA). The rise in BR triggers alterations in internal plant hormones, resulting in faster growth and development of P. ternata. Our findings demonstrated a link between THZ and several metabolic pathway processes, which will enhance our understanding of P. ternata mechanisms. [ABSTRACT FROM AUTHOR]

A new type of imitation rattan was developed via a two-step method that used modified wheat straw as the raw materials and low-density polyethylene to make up wood plastic composite. Post-modification, a graft condensation reaction was carried out between silane as a coupling agent and wheat straw powder, which improved the thermal stability of the composite. A high level of contact and interaction at the fibre-matrix interface was observed. The optimum formula for the first step was 80% wheat straw powder, 4% silane coupling agent, and 16% calcium carbonate, with a modification temperature of 120 °C sustained for 10 min. For the second step, the mechanical properties had been greatly improved with the addition of modified wheat straw fibre and maleic anhydride grafted polypropylene (MA-g-PP). The use of 10% modified straw fibre and 5% MA-g-PP exhibited the highest tensile strength (8.75 MPa) and highest melt index (2.86 g/10 min). In particular, the MA-g-PP had an extremely advantage to the elastic modulus of wheat straw imitation rattan. The elastic modulus reached the maximum value of 2761.70 MPa at the amount of MA-g-PP added reached 5%. Our present study indicated the innovation of a new type of imitation rattan, which provides a new choice for utilizing wheat straw as industrial raw material, and other agricultural by-products containing liginocellulose could be used in a similar way. [ABSTRACT FROM AUTHOR]

Dendrobine is a representative component of Dendrobium nobile, and its pharmacological effects have been extensively studied. Trichoderma longibrachiatum MD33 was isolated from the stem of Dendrobium nobile which can produce dendrobine. In order to understand the effect of Methyl Jasmonate (MeJA) on the production of dendrobine, transcriptome analysis was performed after MeJA treatment in the MD33 and control groups. The dendrobine production of MeJA (20 µmol/L) treatment group was 44.6% higher than that of control. In this study, the RNA sequencing technology was applied, a total of 444 differentially expressed genes (DEGs) in the control and MeJA treatment groups, including 226 up-regulated genes and 218 down-regulated genes. The Kyoto Encyclopedia of Genes and Genomes annotation showed that numbers of DEGs were associated with the putative alkaloid biosynthetic pathway in T Trichoderma longibrachiatum MD33. Several MVA pathway enzyme-coding genes (isopentenyl-diphosphate Delta-isomerase, iphosphomevalonate decarboxylase and farnesyl diphosphate synthase) were found to be differentially expressed, suggesting an active precursor supply for alkaloid biosynthesis after MeJA treatment, in other wise, dendrobine may synthesis through the MVA pathway in MD33. Numerous MeJA-induced P450 family genes, aminotransferase genes and methyltransferase genes were identified, providing several important candidates to further elucidate the dendrobine biosynthetic pathway of T. longibrachiatum MD33. Furthermore, several MeJA-induced transcription factors (TFs) encoding genes were identified, suggesting a complex genetic network affecting the dendrobine in T. longibrachiatum MD33. These findings reveal the regulation mechanism underlying the MeJA-induced accumulation of dendrobine in T. longibrachiatum MD33. [ABSTRACT FROM AUTHOR]

Trichoderma longibrachiatum MD33, a sesquiterpene alkaloid-producing endophyte isolated from Dendrobium nobile , shows potential medical and industrial applications. To understand the molecular mechanisms of sesquiterpene alkaloids production, a comparative transcriptome analysis was performed on strain MD33 and its positive mutant UN32, which was created using Ultraviolet (UV) mutagenesis and nitrogen ion (N+) implantation. The alkaloid production of UN32 was 2.62 times more than that of MD33. One thousand twenty-four differentially expressed genes (DEGs), including 519 up-regulated and 505 down-regulated genes, were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed 139 GO terms and 87 biosynthesis pathways. Dendrobine, arguably the main sesquiterpene alkaloid the strain MD33 produced, might start synthesis through the mevalonate (MVA) pathway. Several MVA pathway enzyme-coding genes (hydroxy-methylglutaryl-CoA synthase, mevalonate kinase, and farnesyl diphosphate synthase) were found to be differentially expressed, suggesting that physical mutagenesis can disrupt genome integrity and gene expression. Some backbone post-modification enzymes and transcript factors were either discovered, suggesting the sesquiterpene alkaloid metabolism in T. longibrachiatum is a complex genetic network. Our findings help to shed light on the underlying molecular regulatory mechanism of sesquiterpene alkaloids production in T. longibrachiatum. [ABSTRACT FROM AUTHOR]

Dendrobium nobile is the only plant that could produce the natural bioactive dendrobine. No other source of dendrobine has been found to date except from D. nobile and via chemical synthesis. In this study, we aimed to examine the potential fungal endophyte isolated from D. nobile stem segments using the molecular method and to detect dendrobine compound through high-performance liquid chromatography (HPLC), gas chromatography–mass spectrometry (GC-MS), and liquid chromatography with tandem mass spectrometry (LC-MS/MS) and their metabolite for their antibacterial activity. The potential dendrobine producer strain was recognized as Trichoderma longibrachiatum based on molecular DNA sequencing and GenBank databases. The T. longibrachiatum MD33 produced dendrobine and other compounds in a potato dextrose medium (PDM), as confirmed by HPLC retention time peak analysis. The HPLC results revealed that T. longibrachiatum MD33 biomass showed a peak retention time of 5.28 ± 0.2 min, similar to wild D. nobile stem dendrobine (5.32 ± 0.2 min) and standard chemical reference dendrobine (5.30 ± 0.2 min), indicating the presence of dendrobine in the fungal biomass. Results of GC-MS and LC-MS analysis revealed that T. longibrachiatum MD33 produced the same molecular weight (263 in GC-MS and 264.195 in LC-MS) of dendrobine as compared with standard chemical reference dendrobine and D. nobile dendrobine. Antibacterial activity data revealed that T. longibrachiatum MD33 produced the strongest bactericidal activity against Bacillus subtilis , Bacillus mycoides , and Staphylococcus species, and the diameter of the bacterial growth inhibition zone was 12 ± 0.2, 9 ± 0.2, and 8 ± 0.2 mm, respectively. To the best of our knowledge, this was the first study to investigate T. longibrachiatum as a dendrobine producer, and the results revealed that T. longibrachiatum was directly involved in the potential production of a similar bioactive compound to D. nobile (dendrobine). In addition, the T. longibrachiatum metabolite exhibited potent antibacterial activity and can be a potential strain for medical and industrial purposes. [ABSTRACT FROM AUTHOR]

Bletilla striata is an endangered traditional Chinese medicinal plant with multiple uses and a slow regeneration rate of its germplasm resources. To evaluate the callus growth kinetics and accumulation of secondary metabolites (SMs), a callus suspension culture was proven to be a valuable approach for acquiring high yields of medicinal compounds. An effective callus suspension culture for obtaining B. striata callus growth and its SMs was achieved with the in vitro induction of calluses from B. striata seeds. The callus growth kinetics and accumulation of SMs were analyzed using a mathematical model. The resulting callus growth kinetic model revealed that the growth curves of B. striata suspension-cultured calluses were sigmoidal, indicating changes in the growth of the suspension-cultured calluses. Improved Murashige and Skoog callus growth medium was the most favorable medium for B. striata callus formation, with the highest callus growth occurring during the stationary phase of the cultivation period. Callus growth acceleration started after 7 days and thereafter gradually decreased until day 24 of the cultivation period and reached its highest at day 36 period in both the dry weight and fresh weight analyses. The coelonin concentration peaked during the exponential growth stage and decreased afterward during the stationary stage of the callus suspension culture. The maximum content of coelonin (approximately 0.3323 mg/g callus dry weight) was observed on the 18th day of the cultivation cycle, while dactylorhin A and militarine reached the highest concentrations at day 24, and p-hydroxybenzyl alcohol at day 39. This investigation also laid a foundation for a multimathematical model to better describe the accumulation variation of SMs. The production of SMs showed great specificity during callus growth and development. This research provided a well-organized way to increase the accumulation and production of SMs during the scaled-up biosynthesis of calluses in B. striata callus suspension cultures. [ABSTRACT FROM AUTHOR]