Search Results (123)

Dendrobium, a prominent genus in the Orchidaceae family, has generated significant research attention due to its demonstrated biological potential, particularly its notable anti-inflammatory and antioxidant activities. In this study, two fractions of fermented Dendrobium officinale polysaccharides (FDOPs) were successfully isolated through a multi-stage purification strategy including gradient ethanol precipitation, gel column chromatography, and ion exchange chromatography with Lactobacillus reuteri CCFM863. Structural characterization revealed that both Dendrobium officinale polysaccharide fractions consisted of (1→4)-β-D-Manp, (1→4)-β-D-Glcp, and (1→4)-α-D-Glcp residues. The anti-inflammatory efficacy and keratinocyte-protective potential of FDOPs (FDOP-1A and FDOP-2A) were investigated by using lipopolysaccharide (LPS)-induced RAW264.7 and HaCaT cells models, which showed significant inhibitions on the inflammatory factors of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), nitric oxide (NO), and interleukin-1 beta (IL-1β); recovered levels of filaggrin (FLG), aquaporin 3 (AQP3), transient receptor potential vanilloid 4 (TRPV4), cathelicidin antimicrobial peptide (CAMP)/LL-37, and adiponectin (ADIPOQ); and the reduced protein expression of the TLR4/IκB-α/NF-κB/NLRP3 pathway. Notably, the FDOPs exhibited a remarkable reactive oxygen species (ROS) scavenging capacity, demonstrating superior antioxidant activity. Therefore, FDOPs show dual anti-inflammatory and antioxidant properties, making them suitable as active ingredients for modulating epidermal inflammation and promoting skin barrier repair. Full article

Dendrobium officinale is a traditional and valuable medicinal herb, with extensive research conducted on its polysaccharides, alkaloids, and other components, yet studies on anthocyanins remain limited. In this study, we analyzed the expression levels of GST family genes in green and purplish D. officinale and found that DoGSTF11 is highly expressed in the purplish variety. DoGSTF11 is localized to the nucleus and cell membrane but lacks transcriptional activation activity. Overexpression of DoGSTF11 in tomato enhances anthocyanin accumulation, suggesting a role in anthocyanin sequestration or transport. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays further revealed that DoGSTF11 interacts with DoGST31, while DoIDD12 and DoNF-YB3 are potential transcriptional regulators based on promoter-binding assays and expression correlation. In conclusion, our study demonstrates that DoGST11 positively regulates anthocyanin accumulation in D. officinale. These findings provide valuable insights into the metabolic engineering of flavonoids in D. officinale. Full article

Dendrobium officinale holds significant value as a traditional medicinal plant, with its stems serving as the primary medicinal component and polysaccharides acting as the key active ingredients. To systematically analyze the biosynthetic pathways of polysaccharides and identify key genes involved in polysaccharide synthesis, this research assessed the water-soluble polysaccharide content and conducted transcriptome sequencing on stem tissues of D. officinale at different developmental stages. The findings revealed that the water-soluble polysaccharide level in D. officinale stems exhibited an increasing trend followed by a decrease, reaching its peak before flowering. Transcriptome analysis identified 5764, 6408, 4477, and 3809 differentially expressed genes (DEGs) in groups S1 vs. S2, S2 vs. S3, S3 vs. S4, and S4 vs. S5, respectively. The Kyoto Encyclopedia of Genes and Genomes Enrichment Analysis (KEGG) demonstrated that the DEGs in the S1 vs. S2, S2 vs. S3, and S3 vs. S4 groups were enriched in the starch and sucrose metabolism pathways. Based on the transcriptome sequencing results, expression heat maps of genes correlated with the polysaccharide synthesis pathways of D. officinale clearly showed changes in the expression of polysaccharide synthesis-related genes at five stages. Using weighted gene co-expression network analysis (WGCNA), three co-expression modules were identified, showing a significant positive correlation with fluctuations in the water-soluble polysaccharide content. From the light blue module with the highest correlation coefficient, 15 key genes potentially closely related to polysaccharide synthesis were identified. This study provides gene resources for the genetic improvement of D. officinale and detailed reference data for further elucidating the molecular mechanisms of polysaccharide biosynthesis. Full article

Extraction techniques play a crucial role in determining the structural attributes and biological functions of polysaccharides. This study aimed to evaluate the physicochemical and biological properties of Dendrobium officinale leaf polysaccharides (DLPs) extracted using various methods, including hot water, acidic, alkali, ultrasound-assisted, and enzyme-assisted extraction. The results indicated that the extraction methods significantly influenced the yield, content, molar ratios of monosaccharides, molecular weight, and structural features of the polysaccharides, as well as their in vitro adsorption, antioxidant, and immunostimulatory activities. Among these extraction methods assessed, enzyme-assisted extraction yielded the highest amount of polysaccharides, characterized by a substantial galacturonic acid residue and exceptional scavenging capability towards free radicals. In contrast, hot water extraction and ultrasound-assisted extraction preserved a triple helix conformation, enabling the polysaccharides to exhibit superior adsorption capabilities for cholesterol and nitrite, as well as significantly increasing the release of nitric oxide and the secretion of TNF-α, IL-6, and IL-1β in RAW264.7 macrophages. These findings suggest that enzyme-assisted, ultrasound-assisted, and hot water extraction are effective approaches to extract DLPs with pronounced biological activity. The selection of the extraction method for DLPs should be tailored to align with the specific requirements of practical applications. Full article

Background/Objectives: Endophytes can produce bioactive metabolites similar to their host plants. CM-YJ44 (Pseudomonas protegens CHA0, 99.24% similarity), an endophyte from Dendrobium officinale, has not yet validated hypoglycemic potential. This study aimed to evaluate its anti-insulin resistance (IR) activity and metabolite profile. Methods: The fermentation broth of CM-YJ44 was separated into three fractions (CM-YJ44-1, -2, and -3) using semi-preparative high-performance liquid chromatography (pre-HPLC). An IR HepG2 cell model was constructed to evaluate their glucose uptake capacity. CM-YJ44-3 was further tested for oxidative stress, inflammatory, and insulin signaling pathway activation. Metabolites in CM-YJ44-3 were preliminarily identified using the Q Exactive Focus LC-MS system (QE), and the dendrobine content was quantified by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). Molecular docking was performed to predict the binding affinities between dendrobine and target proteins. Results: Among the three fractions, CM-YJ44-3 significantly reduced nitric oxide (NO) and reactive oxygen species (ROS) levels in IR cells, enhanced glycogen synthesis, upregulated the activities of pyruvate kinase (PK) and hexokinase (HK), and suppressed the expression of inflammatory factors. Its mechanism of action was mainly through activation of the IRS1/PI3K/Akt/GSK3β/GLUT4 signaling pathway. QE analysis preliminarily identified 24 metabolites in CM-YJ44-3. Quantitative analysis by UPLC-MS/MS showed that the dendrobine content was 78.73 ± 4.29 ng/mL. Molecular docking results indicated that dendrobine exhibited binding energies below −5 kcal/mol with multiple target proteins involved in this signaling pathway, suggesting it may be a key bioactive component responsible for the anti-IR effect. Conclusions: This study provides the first evidence of hypoglycemic bioactive metabolite production by strain CM-YJ44, indicating its potential as a novel microbial candidate for alleviating IR. Full article

Dendrobium officinale, which was rich in bioactive compounds such as polysaccharides, alkaloids, amino acids, and flavonoids, had significant medicinal value and ability to resist stresses. Studies had demonstrated that GATA genes were one of the crucial regulators in controlling plant development and growth and stress response. Genome-wide identification and characterization of the 18 DoGATA genes were displayed. According to phylogenetic relationships, the DoGATA family genes were divided into 4 groups and the conserved motifs of DoGATA1–DoGATA18 within the same group were similar. All DoGATA genes were localized in the nucleus and randomly mapped on 10 chromosomes. The GATA genes in D. officinale experienced one pair of tandem duplication and 4 pairs of segment duplications to expand the family genes. Additionally, we found that the 2000 bp upstream promoter region of the DoGATA genes harbored 23 types of cis-acting elements that were categorized into plant growth and development, phytohormone responsiveness, and stress responsiveness. DoGATA1–DoGATA18 were diversely expressed across different tissues (root, leaf, stem, flower), exposed to salt stress, and following MeJA treatment. Co-expression analysis between DoGATA and enzyme-encoding genes involved in the biosynthesis of flavone showed that DoCHI (LOC110104562) and DoGTMT (LOC110098370) may be potential downstream targets of DoGATA16 to regulate flavonoid biosynthesis to adapt to salt stress. Furthermore, we confirmed that DoGATA16 may act as a key member to resist stress. The collective findings of this study shed light on the function of GATA genes and molecular breeding of D. officinale. Full article

Dendrobium is a famous edible and medicinal plants, and polysaccharides are their main bioactive components. Polysaccharides from five species, namely, DO (Dendrobium officinale Kimura et Migo), DH (Dendrobium huoshanense C. Z. Tang et S. J. Cheng), DNL (Dendrobium nobile Lindl.), DFH (Dendrobium fimbriatum Hook.), and DCL (Dendrobium chrysanthum Lindl.), were compared based on molecular weight (Mw), monosaccharide composition, and glycosidic bond types. The results showed that Dendrobium polysaccharides (DPs) contain relatively simple compositional monosaccharides and mainly consist of mannose (Man) and glucose (Glc), along with small amounts of arabinose (Ara), xylose (Xyl), and galactose (Gal). The Am/Ag (the ratio of Man to Glc) values in DO, DH, and DNL polysaccharides were 3.23, 3.81, and 3.88, while those in DFH and DCL were 0.45 and 0.81. DPs are mainly composed of →4)Manp(1→ and →4)Glcp(1→, but their molar ratios were different. →4)Manp(1→ and →4)Glcp(1→ ratios were 2.85, 2.92, 1.50, 1.45, and 1.05 in DO, DH, DNL, DFH, and DCL, respectively. Hierarchical cluster analysis (HCA) showed that there were significant differences in structural information, especially in glycosidic bond types and proportions. DH, DO, and DCL were clustered into different groups based on glycosidic bond types and proportions, respectively. Moreover, the five species of Dendrobium could significantly inhibit NO production and apoptosis induced by LPS in RAW 264.7, especially DH. The results of a correlation analysis of structure and anti-inflammatory activity showed that polysaccharides with a high →4)Manp(1→/→4)Glcp(1→ ratio and a molecular weight distribution between 3.343 × 10⁵ Da and 13.540 × 10⁵ Da had better anti-inflammatory activity. The results indicated that the quality evaluation of Dendrobium in clinical applications should investigate molecular weight and the composition of the glycoside bond types and proportions to ensure the consistency of curative effects. Full article

The growing prevalence of obesity is being increasingly acknowledged as a major public health issue. This mainly stems from the excessive intake of dietary fats. Dendrobium officinale (DO), recognized as an herb with dual roles of food and medicine, is renowned for its diverse health-promoting effects. Nevertheless, the specifics of its antiobesity and anti-inflammatory properties and the underlying mechanisms are still obscure. The present study shows that treatment with Dendrobium officinale extract (DOE) alleviates obesity, liver steatosis, inflammation, and oxidative stress in rats that are obese due to a high-fat diet (HFD). Firstly, with respect to HFD obese rats, higher doses of DOE significantly reduced TG, TC, LDL-C, blood glucose, and liver AST and ALT, along with lipid droplets. Meanwhile, DOE supplementation significantly reduced oxidative stress induced by ROS and MDA and increased the levels of GSH-Px and SOD in liver tissues. Furthermore, integrated analysis of transcriptomic and microbiomic data revealed that DOE modulated inflammatory responses through the NF-κB/IκB pathway. This regulatory mechanism was evidenced by corresponding changes in the protein expression levels of both NF-κB and IκB. Additionally, DOE was found to modulate gut microbiota composition in obese rats, specifically reducing the relative abundance of Bilophila while increasing beneficial bacterial populations, particularly the genera Akkermansia and Roseburia. These findings suggest that DOE may help retain the homeostasis of the gut microbiota and improve metabolic health by regulating inflammation in the liver and intestine, thereby providing protection against obesity and related metabolic syndromes. Our study demonstrates that DOE, as a natural botanical extract, can effectively facilitate the prevention or treatment of metabolic syndrome through precision dietary interventions. Full article

The critically endangered orchid Dendrobium officinale, valued for its medicinal properties, depends on specific seedling-associated mycorrhizal fungi (SAMF) for successful early-stage seedling development. However, conservation efforts are often hindered by difficulties in obtaining suitable SAMF, leading to poor seedling establishment in both natural and cultivated environments. In this study, we explored the growth-promoting effects of SAMF and evaluated the performances of synthetic fungal combinations. Our results demonstrated that mycorrhizal fungi, widely distributed across multiple habitats with high isolation frequencies, significantly promoted the growth of D. officinale, with specific fungi favoring different growth parameters. Tulasnella sp. TP-2 and TP-3 significantly improved stem diameter and plant height by 2.622 mm and 4.621 cm, while Tulasnella sp. TP-8 significantly increased tillering by a factor of 4.47. Additionally, Tulasnella sp. TP-11 and TP-13 markedly increased the number of new leaves (4.45) and new roots (2.688), respectively, identifying them as essential core OMFs for D. officinale seedlings. Contrary to expectations, synthetic fungal combinations composed of core orchid mycorrhizal fungi (core OMFs) did not exhibit synergistic growth-promoting effects. Instead, pronounced offset effects were observed, indicating that interactions between fungi may introduce competition or inhibition, limiting their collective ability to enhance plant growth. Our results confirmed that the core OMFs significantly promoted the growth of D. officinale seedlings. These core OMFs can serve as essential components in specialized microbial fertilizers for D. officinale, improving growth efficiency and yield, and supporting the sustainable development of the D. officinale industry. Full article

The Dof gene family represents a class of plant-specific transcription factors that play crucial regulatory roles in various biological processes, including plant growth, development, and responses to abiotic stress. However, genome-wide identification and functional characterization of the Dof gene family remain unexplored in Dendrobium officinale. In this study, we performed a genome-wide identification and functional analysis of the DoDof gene family. A total of 28 Dof family members were identified and named DoDof1–28 based on genome annotation data. Phylogenetic analysis classified these genes into four major groups (A–D) and further subdivided them into nine subfamilies. Gene structure analysis revealed that most DoDofs lack introns, with no distinct specificity observed among different subfamilies and considerable diversity within the same subfamily. Sequence alignment analysis demonstrated that all DoDof proteins contain a conserved Dof domain consisting of 52 amino acids, which includes a C2-C2 zinc finger motif and a DNA-binding domain. MEME analysis revealed that the conserved motif composition exhibits a certain degree of conservation among DoDof proteins, but significant differences exist across subfamilies. Expression pattern analysis demonstrated that DoDofs have exhibited diverse expression profiles across different developmental stages, tissues, and under abiotic stresses (such as low temperature, salinity, and drought) in D. officinale, suggesting their potential roles in plant development and stress responses. Subcellular localization analysis indicated that DoDof15, DoDof22, and DoDof24 are localized exclusively in the nucleus. Yeast one-hybrid assays revealed that DoDof22 binds to the promoter of the ABA receptor DoPYL9, while DoDof15 and DoDof24 bind to the promoter of the bHLH transcription factor DobHLH68. These results suggest that DoDof proteins may regulate the growth, development, and stress response processes of D. officinale by binding to the promoters of target genes. This study provides critical insights into the functional roles of Dof transcription factors in Orchidaceae family and establishes a theoretical foundation for molecular breeding and stress resistance improvement in D. officinale. Full article

Polysaccharides derived from Dendrobium officinale have been demonstrated to exhibit metabolic regulatory properties. However, the correlation between their structure and function, particularly their mechanism of action through gut microbiota, remains underexplored. This study systematically elucidates the structural characteristics of Dendrobium officinale polysaccharide (DOP) from the Guizhou (GZ) and Zhejiang (ZJ) provinces of China using nuclear magnetic resonance (NMR) and a series of chromatographic analyses, revealing their unique molecular features. Additionally, the metabolic regulatory activities were assessed through α-glucosidase inhibitory assay and in vitro intestinal flora activity assay. The findings include the following: (1) both DOP-GZ and DOP-ZJ predominantly consist of glycosidic linkages of β-1,4-Manp and β-1,4-Glcp; (2) zhe monosaccharide composition ratios of mannose to glucose are 2.51:1 for DOP-GZ and 2.66:1 for DOP-ZJ, with molecular weights of 356 kDa and 544 kDa, respectively, indicating significant structural differences between DOPs from different sources; (3) treatment with DOP-GZ and DOP-ZJ led to alterations in the α-diversity indices and Firmicutes-to-Bacteroidota ratios; (4) more importantly, DOP-GZ and DOP-ZJ significantly increase the abundance of beneficial bacteria (e.g., g_Proteobacteria_unclassified) while suppressing the growth of pathogenic bacteria (e.g., f_Enterobacteriaceae_unclassified), with statistically significant results. These findings not only uncover a novel mechanism by which DOPs regulate metabolism through gut microbiota but also provide a crucial theoretical basis for the application of DOPs in functional foods and pharmaceutical development. Full article

Dendrobium officinale is an economically important orchid species that is sensitive to cold stress. Understanding the molecular and metabolic mechanisms underlying its response to cold is crucial for developing strategies to improve its cold tolerance. In this study, we constructed a comprehensive cold stress response dataset for D. officinale and characterized its regulatory landscape in response to varying cold stress conditions. The glycine metabolism-related genes Dca003913 and Dca022726 play pivotal roles in both cold and drought stress adaptation, and their expression is not upregulated by hormones or fungi infection. Carbohydrate metabolism showed specific dynamic changes in freezing injury cells, which involved a variety of hormonal responses. The abundance of sphingolipids was notably higher in the freezing treatment (FT) compared to the freezing recovery (FR) plants, indicating specialized metabolic adaptations at different cold intensities. An alternative splicing (AS) analysis identified 368 DAS genes, with spliceosome pathways significantly enriched. Three key ubiquitination proteins (PKU64802, XP_020672210, and PKU75555) were found to regulate splicing factors, which showed increased abundance in cold stress. This study highlights the roles of metabolic reprogramming and RNA splicing in cold adaptation, revealing a complex molecular network activated in response to cold stress. Full article

Dendrobium officinale (DO) is a well-known medicinal and edible plant, yet its impact on the quality of noodles has been infrequently reported. In this study, DO was incorporated into multi-grain flour in varying proportions (0, 2, 4, 6, 8%) to prepare noodles, and their quality was assessed. The percentage increase in DO decreased the cooking loss, whiteness, appearance, and taste of the noodles while simultaneously enhancing their water absorption, adhesiveness, smoothness, and starch digestion resistance. Lower supplemental levels of DO (2–4%) facilitated the water absorption of protein and the formation of a dense and extensive protein network surrounding the partially gelatinized starch, which was characterized by higher relative crystallinity. The highest sensory score (77.4) and greatest content of slowly digestible starch content (38%) were observed in the noodles containing 4% DO. Conversely, higher percentages of DO (6–8%) diluted and compromised the protein network in the cooked noodles, leading to water migration from protein to starch. The excessive polysaccharides from DO tended to complex with fully gelatinized starch, promoting starch aggregation and interactions between starch and non-starch components. This ultimately resulted in the highest adhesiveness and resistant starch content (34%) in the cooked noodles with 8% DO. These findings provide a reference for enhancing noodle quality by regulating the amount of DO added, thereby promoting the application of DO in cereal-based food products. Full article

Encyclia Hook. is a tropical orchid known for its delightful fragrance and distinctive flower shapes, which have been widely used as superior parents for inter and intrageneric breeding. In this study, karyotype analysis shows that the number of chromosomes in diploid plants of Encyclia is 40, with all species exhibiting mesial and central filamentous chromosomes. The karyotype of diploid plants is primarily 2B. Among the three detected intergeneric hybrids, both Enanthleya Circus Lady ‘Coastal Star’ and Guaricyclia Kyoguchi ‘Fumi’ are triploid, while Robertsara ‘Green Wonder’ is tetraploid. By evaluating various lysates and tissues, a flow cytometry system (FCM) is developed with Galbraith’s buffer (GLB) and tender leaves. By using Dendrobium officinale as an external reference, the genome size of the Encyclia species and its intra and intergeneric hybrids are assessed, which ranges from 1.07 Gb to 3.23 Gb. These results will establish a foundation for high-throughput identification of germplasms, advance crossbreeding efforts, and enhance the understanding of the genome in Encyclia. Full article

Background: The mechanism of Dendrobium officinale polysaccharide-based nanocarriers in enhancing photodynamic immunotherapy in colorectal cancer (CRC) remains poorly understood. Methods: The effects of TPA-3BCP-loaded cholesteryl hemisuccinate–Dendrobium officinale polysaccharide nanoparticles (DOP@3BCP NPs) and their potential molecular mechanism of action in a tumor-bearing mouse model of CRC were investigated using non-targeted metabolomics and transcriptomics. Meanwhile, a histopathological analysis (H&E staining, Ki67 staining, and TUNEL assay) and a qRT-PCR analysis revealed the antitumor effects of DOP@3BCP NPs with and without light activation. Results: Through metabolomics and transcriptomics analysis, we found an alteration in the metabolome and functional pathways in the examined tumor tissues. The metabolic analysis showed 69 and 60 differentially expressed metabolites (DEMs) in positive- and negative-ion modes, respectively, in the treated samples compared to the Control samples. The transcriptomics analysis showed that 1352 genes were differentially expressed among the three groups. The differentially regulated functional pathways were primally related to the antitumor immune response. The results of the pathological histology assay and qRT-PCR analysis verified the findings of the integrated metabolomics and transcriptomics analysis. Conclusions: Overall, our findings elucidate the potential antitumor mechanisms of the D. officinale polysaccharide-based nanocarrier in enhancing photodynamic immunotherapy in CRC. Full article