Search Results (1,075)

Coffee cherry pulp (CCP), a coffee by-product rich in pectin and phenolic compounds, serves as a valuable substrate for microbial enzyme production, improving the nutritional and antioxidant properties of poultry feed. This study evaluated the potential of Kluyveromyces marxianus ST5 to produce pectin-degrading enzymes using CCP. Under unoptimized conditions, the pectin lyase (PL) and polygalacturonase (PG) activities were 3.29 ± 0.22 and 6.32 ± 0.13 U/mL, respectively. Optimization using a central composite design (CCD) identified optimal conditions at 16.81% (w/v) CCP, 5.87% (v/v) inoculum size, pH 5.24, and 30 °C for 48 h, resulting in PL and PG activities of 9.17 ± 0.20 and 15.78 ± 0.14 U/mL, representing increases of 178.7% and 149.7% over unoptimized conditions. Fermented CCP was further evaluated using an in vitro chicken gastrointestinal digestion model. Peptide release increased by 66.2% compared with unfermented CCP. Antioxidant capacity also improved, with significant increases observed in DPPH (32.4%), ABTS (45.0%), and FRAP (42.3%) assays, along with an 11.1% increase in total phenolic content. These results demonstrate that CCP bioconversion by K. marxianus ST5 enhances digestibility and antioxidant properties, supporting its potential as a sustainable poultry feed additive and contributing to the valorization of agro-industrial waste. Full article

Salinity is a major abiotic stress limiting black gram (Vigna mungo) productivity, particularly in arid and semi-arid regions. Saline soils negatively impact plant growth, nodulation, nitrogen fixation, and yield. This study evaluated the efficacy of co-inoculating salt-tolerant plant growth-promoting bacteria Paenibacillus sp. SPR11 and Bradyrhizobium yuanmingense PR3 on black gram performance under saline field conditions (EC: 8.87 dS m⁻¹; pH: 8.37) with low organic carbon (0.6%) and nutrient deficiencies. In vitro assays demonstrated the biocontrol potential of SPR11, inhibiting Fusarium oxysporum and Macrophomina phaseolina by 76% and 62%, respectively. Germination assays and net house experiments under 300 mM NaCl stress showed that co-inoculation significantly improved physiological traits, including germination rate, root length (61.39%), shoot biomass (59.95%), and nitrogen fixation (52.4%) in nitrogen-free media. Field trials further revealed enhanced stress tolerance markers: chlorophyll content increased by 54.74%, proline by 50.89%, and antioxidant enzyme activities (SOD, CAT, PAL) were significantly upregulated. Electrolyte leakage was reduced by 55.77%, indicating improved membrane stability. Agronomic performance also improved, with co-inoculated plants showing increased root length (7.19%), grain yield (15.55 q ha⁻¹; 77.04% over control), total biomass (26.73 q ha⁻¹; 57.06%), and straw yield (8.18 q ha⁻¹). Pod number, seed count, and seed weight were also enhanced. Nutrient analysis showed elevated uptake of nitrogen, phosphorus, potassium, and key micronutrients (Zn, Fe) in both grain and straw. To the best of our knowledge, this is the very first field-based report demonstrating the synergistic benefits of co-inoculating Paenibacillus sp. SPR11 and Bradyrhizobium yuanmingense PR3 in black gram under saline, nutrient-poor conditions without external nitrogen inputs. The results highlight a sustainable strategy to enhance legume productivity and resilience in salt-affected soils. Full article

Tetrabromobisphenol A (TBBPA), a widely utilised brominated flame retardant, demonstrates toxicological effects in aquatic organisms. Tea polyphenols (TPs), natural compounds found in tea leaves, exhibit both antioxidant and anti-inflammatory activities. The kidney is one of the major metabolic organs in common carp and serves as a target organ for toxic substances. This study evaluated the therapeutic potential of TPs in mitigating TBBPA-induced nephrotoxicity in common carp. Common carp were exposed to 0.5 mg/L TBBPA in water and/or fed a diet supplemented with 1 g/kg TPs for 14 days. In vitro, primary renal cells were treated with 60 μM TBBPA and/or 2.5 μg/L TPs for 24 h. Methods included histopathology, TUNEL assay for apoptosis, ROS detection, and molecular analyses. Antioxidant enzymes (SOD, CAT) and inflammatory cytokines (IL-1β, IL-6, TNF-α) were quantified using ELISA kits. Results showed that TBBPA induced oxidative stress, and activated the ROS-PI3K/AKT-NF-κB pathway, thereby resulting in inflammatory responses. TBBPA upregulated apoptosis-related genes (Caspase-3, Bax, and Bcl-2) and induced apoptosis. TBBPA upregulated the expression of RIPK3/MLKL, thereby exacerbating necroptosis. TPs intervention significantly mitigated these effects by reducing ROS, suppressing NF-κB activation, and restoring antioxidant enzyme activities (SOD, CAT). Moreover, TPs attenuated apoptosis and necrosis in the carp kidney, thereby enhancing the survival ability and immunity of common carp. Full article

Background/Objectives: Vitex agnus-castus has been traditionally used to treat hormonal disorders, and recent evidence suggests its potential anticancer properties. However, its effects on gastric cancer remain unclear. Methods: This study examined the cytotoxic, apoptotic, and anti-metastatic effects of hydroalcoholic Vitex agnus-castus seed extract in gastric cancer cells. Antioxidant capacity (DPPH, ABTS) and total phenolic and flavonoid contents were analyzed. Cytotoxicity was assessed using the MTT assay in HGC27, MKN45, and AGS gastric cancer cell lines and CCD-1072Sk fibroblasts. Apoptosis, mitochondrial membrane potential (MMP), and cell cycle changes were evaluated via Annexin V-FITC/PI, Rhodamine 123, and PI staining, respectively. RT-qPCR and gene enrichment analyses were conducted to investigate the molecular mechanisms. Apoptosis-related protein expression was analyzed through enzyme-linked immunosorbent assay (ELISA). Results: The extract exhibited high antioxidant activity and a significant phenolic content. It reduced cell viability in a dose-dependent manner in gastric cancer cells, while exerting low toxicity in fibroblasts. It significantly increased apoptosis, induced G0/G1-phase cell cycle arrest, upregulated pro-apoptotic genes (CASP3, CASP7, TP53, BCL2L11), and downregulated anti-apoptotic genes (XIAP, NOL3). Gene enrichment analysis highlighted pathways like apoptosis, necrosis, and cysteine endopeptidase activity. The extract also disrupted MMP, inhibited migration and spheroid formation, suppressed EMT markers (SNAIL, SLUG, TWIST1, N-CADHERIN), and upregulated E-CADHERIN. The expression of Caspase 3 and Bax proteins increased and Bcl2 protein decreased. Conclusions: These findings suggest that Vitex agnus-castus seed extract exerts strong anticancer effects in gastric cancer cells by promoting apoptosis, reducing proliferation, and inhibiting migration. Further studies are warranted to explore its clinical relevance. Full article

Callistemon citrinus has shown antioxidant and anti-inflammatory properties in certain tissues. However, its impact on the brain remains unproven. This study investigates the effect of C. citrinus extract and phytosomes on the oxidative status of the brains of rats fed a high-fat–fructose diet (HFD). Fifty-four male Wistar rats were randomly divided into nine groups (n = 6). Groups 1, 2, and 3 received a standard chow diet; Group 2 also received the vehicle, and Group 3 was supplemented with C. citrinus extract (200 mg/kg). Groups 4, 5, 6, 7, 8, and 9 received a high-fat diet (HFD). Additionally, groups 5, 6, 7, 8, and 9 were supplemented with orlistat at 5 mg/kg, C. citrinus extract at 200 mg/kg, and phytosomes loaded with C. citrinus at doses of 50, 100, and 200 mg/kg, respectively. Administration was oral for 16 weeks. Antioxidant enzymes, biomarkers of oxidative stress, and fatty acid content in the brain were determined. A parallel artificial membrane permeability assay (PAMPA) was employed to identify compounds that can cross the intestinal and blood–brain barriers. The HFD group (group 4) increased body weight and adipose tissue, unlike the other groups. The brain fatty acid profile showed slight variations in all of the groups. On the other hand, group 4 showed a decrease in the activities of antioxidant enzymes SOD, CAT, and PON. It reduced GSH level, while increasing GPx activity as well as MDA, 4-HNE, and AOPP levels. C. citrinus extract and phytosomes restore the antioxidant enzyme activities and mitigate oxidative stress in the brain. C. citrinus modulates oxidative stress in brain tissue through 1.8-cineole and α-terpineol, which possess antioxidant and anti-inflammatory properties. Full article

Flavonoids serve as crucial plant antioxidants in drought tolerance, yet their antioxidant regulatory mechanisms within mycorrhizal plants remain unclear. In this study, using a two-factor design, trifoliate orange (Poncirus trifoliata (L.) Raf.) seedlings in the four-to-five-leaf stage were either inoculated with Funneliformis mosseae or not, and subjected to well-watered (70–75% of field maximum water-holding capacity) or drought stress (50–55% field maximum water-holding capacity) conditions for 10 weeks. Plant growth performance, photosynthetic physiology, leaf flavonoid content and their antioxidant capacity, reactive oxygen species levels, and activities and gene expression of key flavonoid biosynthesis enzymes were analyzed. Although drought stress significantly reduced root colonization and soil hyphal length, inoculation with F. mosseae consistently enhanced the biomass of leaves, stems, and roots, as well as root surface area and diameter, irrespective of soil moisture. Despite drought suppressing photosynthesis in mycorrhizal plants, F. mosseae substantially improved photosynthetic capacity (measured via gas exchange) and optimized photochemical efficiency (assessed by chlorophyll fluorescence) while reducing non-photochemical quenching (heat dissipation). Inoculation with F. mosseae elevated the total flavonoid content in leaves by 46.67% (well-watered) and 14.04% (drought), accompanied by significantly enhanced activities of key synthases such as phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), chalcone isomerase (CHI), 4-coumarate:coA ligase (4CL), and cinnamate 4-hydroxylase (C4H), with increases ranging from 16.90 to 117.42% under drought. Quantitative real-time PCR revealed that both mycorrhization and drought upregulated the expression of PtPAL1, PtCHI, and Pt4CL genes, with soil moisture critically modulating mycorrhizal regulatory effects. In vitro assays showed that flavonoid extracts scavenged radicals at rates of 30.07–41.60% in hydroxyl radical (•OH), 71.89–78.06% in superoxide radical anion (O₂^•−), and 49.97–74.75% in 2,2-diphenyl-1-picrylhydrazyl (DPPH). Mycorrhizal symbiosis enhanced the antioxidant capacity of flavonoids, resulting in higher scavenging rates of •OH (19.07%), O₂^•− (5.00%), and DPPH (31.81%) under drought. Inoculated plants displayed reduced hydrogen peroxide (19.77%), O₂^•− (23.90%), and malondialdehyde (17.36%) levels. This study concludes that mycorrhizae promote the level of total flavonoids in trifoliate orange by accelerating the flavonoid biosynthesis pathway, hence reducing oxidative damage under drought. Full article

Isoquercitrin, a monoglucoside form of quercetin, exhibits superior antioxidant, anti-inflammatory, and cardiovascular protective effects in comparison to its precursor, rutin. However, its natural abundance is limited. This study aimed to increase the functional value of Diospyros lotus leaf extract through enzymatic conversion of rutin to isoquercitrin using α-l-rhamnosidase and to evaluate the changes in biological activities after conversion. A sugar-free D. lotus leaf extract was prepared and subjected to enzymatic hydrolysis with α-l-rhamnosidase under optimized conditions (pH 5.5, 55 °C, and 0.6 U/mL). Isoquercitrin production was monitored via high-performance liquid chromatography. Antioxidant and anti-inflammatory activities were assessed using the 2,2-diphenyl-1-picrylhydrazyl radical scavenging and lipoxygenase (LOX) inhibition assays, respectively. The enzymatic reaction resulted in complete conversion of 30 mM rutin into isoquercitrin within 180 min, increasing isoquercitrin content from 9.8 to 39.8 mM. The enzyme-converted extract exhibited significantly enhanced antioxidant activity, with a 48% improvement in IC₅₀ value compared with the untreated extract. Similarly, LOX inhibition increased from 39.2% to 48.3% after enzymatic conversion. Both extracts showed higher inhibition than isoquercitrin alone, indicating synergistic effects of other phytochemicals present in the extract. This study is the first to demonstrate that α-l-rhamnosidase-mediated conversion of rutin to isoquercitrin in D. lotus leaf extract significantly improves its antioxidant and anti-inflammatory activities. The enzymatically enhanced extract shows potential as a functional food or therapeutic ingredient. Full article

Soil salinization poses a significant constraint to agricultural productivity. However, certain plant growth-promoting bacteria (PGPB) can mitigate salinity stress and enhance crop performance. In this study, a bacterial isolate, R-18, isolated from saline-alkali soil in Ningxia, China, was identified as Enterobacter bugandensis based on 16S rRNA gene sequencing. The isolate was characterized for its morphological, biochemical, and plant growth-promoting traits and was evaluated for its potential to alleviate NaCl-induced stress in maize (Zea mays L.) under hydroponic conditions. Isolate R-18 exhibited halotolerance, surviving at NaCl concentrations ranging from 2.0% to 10.0%, and alkaliphilic adaptation, growing at pH 8.0–11.0. Biochemical assays confirmed it as a Gram-negative bacterium, displaying positive reactions in the Voges–Proskauer (V–P) tests, catalase activity, citrate utilization, fluorescent pigment production, starch hydrolysis, gelatin liquefaction, and ammonia production, while testing negative for the methyl red and cellulose hydrolysis. Notably, isolate R-18 demonstrated multiple plant growth-promoting attributes, including nitrogen fixation, phosphate and potassium solubilization, ACC deaminase activity, and indole-3-acetic acid (IAA) biosynthesis. Under 100 mM NaCl stress, inoculation with isolate R-18 significantly enhanced maize growth, increasing plant height, stem dry weight, root fresh weight, and root dry weight by 20.64%, 47.06%, 34.52%, and 31.25%, respectively. Furthermore, isolate R-18 improved ion homeostasis by elevating the K⁺/Na⁺ ratio in maize tissues. Physiological analyses revealed increased chlorophyll and proline content, alongside reduced malondialdehyde (MDA) levels, indicating mitigated oxidative damage. Antioxidant enzyme activity was modulated, with decreased superoxide dismutase (SOD) and peroxidase (POD) activities but increased catalase (CAT) activity. These findings demonstrated that Enterobacter bugandensis R-18 effectively alleviated NaCl-induced growth inhibition in maize by enhancing osmotic adjustment, reducing oxidative stress, and improving ion balance. Full article

Iridoids are compounds recognized for their neuroprotective properties and their potential application in the treatment of neurodegenerative diseases. Geniposide (GP) and asperuloside (ASP) are iridoids that have demonstrated some biological activities. In this study, the potential neuroprotective effects of these iridoids were evaluated through in silico and in vivo assays, using Caenorhabditis elegans (C. elegans) strains CF1553 (sod-3::GFP), GA800 (cat::GFP), and CL2166 (gst-4::GFP). The results suggested that neither compound appears to have good passive permeability through the blood–brain barrier (BBB). However, an active transport mechanism involving the glucose transporter GLUT-1 may be present, as both compounds contain glucose in their molecular structure. In addition, they can inhibit the activity of both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). GP at 1 and 2 mM reversed the H₂O₂-induced increase in sod-3 expression, while ASP at 1 and 2 mM reversed the increase in gst-4 expression. Worm survival was more adversely affected by higher concentrations of GP than ASP, although both similarly reduced acetylcholinesterase activity. These findings suggest that GP and ASP exhibit very low toxicity both in silico and in vivo in C. elegans, and positively modulate key enzymes involved in antioxidant pathways, highlighting their potential for neuroprotective applications. Full article

Background/Objectives: Antimicrobial resistance (AMR) is a health related threat world-wide. Biosynthesized gold nanoparticles (AuNPs) using plant extracts have been reported to exhibit certain biological activity. This study aimed to biosynthesize AuNPs using an aqueous extract of Eruca sativa leaves and to evaluate their biocompatibility, antimicrobial activity, and antioxidant properties. Methods: AuNPs were biosynthesized using an aqueous extract of Eruca sativa leaves. Their biocompatibility was evaluated through hemolytic activity and assessments of hepatic and renal functions in rats. AuNPs were biologically evaluated as antimicrobial and antioxidant agents. Results: The AuNPs exhibited particle sizes of 27.78 nm (XRD) and 69.41 nm (AFM). Hemolysis assays on red blood cells revealed negligible hemolytic activity (<1%). Hepatic enzyme levels, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) were studied. ALT, AST, and ALP levels showed no significant changes compared to the negative control. However, LDH levels were elevated at higher concentration (52.8 µg/mL), while the lower concentration (26.4 µg/mL) appeared to be safer. Renal biomarkers, urea and creatinine, showed no significant changes at either concentration, indicating minimal nephrotoxicity. The antimicrobial activity of AuNPs, plant extract, and gold salt was tested against five microorganisms: two Gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae), two Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa), and a fungal strain (Candida albicans). The AuNPs exhibited minimum inhibition concentrations (MICs) of 13.2 µg/mL against S. aureus and S. pneumoniae, 26.4 µg/mL against E. coli and C. albicans, and 39.6 µg/mL against P. aeruginosa, suggesting selectivity towards Gram-positive bacteria. Furthermore, the AuNPs demonstrated strong antioxidant activity, surpassing that of vitamin C. Conclusions: The biosynthesized AuNPs exhibited promising biocompatibility, selective antimicrobial properties, and potent antioxidant activity, supporting their potential application in combating the AMR. Full article

Acute hepatopancreatic necrosis disease (AHPND), caused by the bacterium Vibrio parahaemolyticus, is a major threat to global shrimp aquaculture. In this study, we evaluated the therapeutic effects of phage therapy in Litopenaeus vannamei challenged with AHPND-causing Vibrio parahaemolyticus. Phage application at various concentrations significantly improved shrimp survival, with the 1 ppm group demonstrating the highest survival rate. Enzymatic assays revealed that phage-treated shrimp exhibited enhanced immune enzyme activities, including acid phosphatase (ACP), alkaline phosphatase (AKP), and lysozyme (LZM). In addition, antioxidant defenses such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), and total antioxidant capacity (T-AOC) significantly improved, accompanied by reduced malondialdehyde (MDA) levels. Serum biochemical analyses demonstrated marked improvements in lipid metabolism, particularly reductions in triglyceride (TG), total cholesterol (TC), and low-density lipoprotein (LDL), alongside higher levels of beneficial high-density lipoprotein (HDL). Transcriptomic analysis identified 2274 differentially expressed genes (DEGs), notably enriched in pathways involving fatty acid metabolism, peroxisome functions, lysosomes, and Toll-like receptor (TLR) signaling. Specifically, phage treatment upregulated immune and metabolic regulatory genes, including Toll-like receptor 4 (TLR4), myeloid differentiation primary response protein 88 (MYD88), interleukin-1β (IL-1β), nuclear factor erythroid 2-related factor 2 (Nrf2), and peroxisome proliferator-activated receptor (PPAR), indicating activation of innate immunity and antioxidant defense pathways. These findings suggest that phage therapy induces protective immunometabolic adaptations beyond its direct antibacterial effects, thereby providing an ecologically sustainable alternative to antibiotics for managing bacterial diseases in shrimp aquaculture. Full article

The genera Allium (Liliaceae) and Anchusa (Boraginaceae) are flowering plant genera with a rich diversity, also including the Allium kharputense Freyn & Sint. and Anchusa azurea Mill. var. azurea species. The antioxidant, anti-Alzheimer’s disease (AD), antidiabetic, and antiglaucoma effects of the Allium kharputense Freyn & Sint. and Anchusa azurea Mill. var. azurea species, which are commonly eaten foods in the Southeast of Türkiye in the treatment of several diseases, were studied. To interpret the antioxidant capacities of ethanol extract of two plant species, aerial parts were analyzed by ABTS and DPPH assays. The IC₅₀ values of A. kharputense and A. azurea ethanol and water extracts for ABTS^•+ activities were recorded in the range of 30.93 to 33.94 µg/mL and 33.45 to 33.78 µg/mL, respectively. Also, DPPH^• activities were measured at 30.78 to 36.87 µg/mL and 31.67 to 32.45 µg/mL, respectively. The best of the IC₅₀ values was measured in the ethanol extract of A. kharputense as 30.78 µg/mL for DPPH scavenging activity. The total phenolic and flavonoid quantities in A. kharputense and A. azurea plants were measured. The highest phenolic and flavonoid contents of A. kharputense and A. azurea species were recorded in amounts of 445.52 and 327.35 mg GAE/g in ethanol extracts, respectively, and 332.88 and 234.03 mg QE/g in ethanol extracts, respectively. The effects of A. kharputense and A. azurea on diabetes, AD, and glaucoma were studied on the target enzymes of diseases. The most efficient IC₅₀ values were recorded at 10.72 μg/mL against α-glycosidase, 35.01 μg/mL against AChE, 38.05 μg/mL against BChE, 9.21 μg/mL towards hCA I, and 81.02 μg/mL towards hCA II isoenzymes. The kinds and amounts of phenolic compounds in A. kharputense and A. azurea were determined using LC-MS/MS against 53 standards. A. kharputense and A. azurea plants have prospective use in enhancing glaucoma, diabetes, AD, Parkinson’s disease, epilepsy, and cancerous disorders. Full article

Skin aging is a natural biological process that can be accelerated by free radical induction, leading to a reduction in skin elasticity and the formation of wrinkles due to the depletion of elastin. Eugenia uniflora (dewandaru) is a promising plant believed to possess anti-aging properties, primarily attributed to its major constituents, myricitrin and quercetin. This study aimed to investigate the anti-elastase and antioxidant properties of Eugenia uniflora stem bark, ripe fruit, and seed extracts. Extracts were obtained using an ultrasound-assisted extraction (UAE) method with 70% ethanol. Quantitative phytochemical analysis involved measuring the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. Bioactive constituents were identified using LC-MS analysis, and their interactions with target enzymes were further evaluated through in silico molecular docking. The results demonstrated that the E. uniflora seed extract exhibited the highest antioxidant activity, with an IC₅₀ of 5.23 µg/mL (DPPH assay) and a FRAP value of 3233.32 µmol FeSO₄/g. Furthermore, the ethanolic seed extract showed significant anti-elastase activity with an IC₅₀ of 114.14 µg/mL. Molecular docking predicted strong potential for several compounds as pancreatic elastase inhibitors, including 5-phenylvaleric acid, 2-(3-phenylpropyl)phenol, n-amylbenzene, 2-aminoadipic acid, and traumatin, each showing a prediction activity (PA) value exceeding 0.6. Notably, these compounds also exhibited inhibitory activity against tyrosinase. These findings collectively underscore the significant promise of E. uniflora seed extract as a novel and natural candidate for pharmacocosmeceutical product development, particularly for anti-aging applications. Full article

Objectives: Light intensity is a critical environmental factor regulating plant growth, development, and stress adaptation. However, the physiological and molecular mechanisms underlying light responses in Aconitum kusnezoffii, a valuable alpine medicinal plant, remain poorly understood. This study aimed to elucidate the adaptive strategies of A. kusnezoffii under different light intensities through integrated physiological and transcriptomic analyses. Methods: Two-year-old A. kusnezoffii plants were exposed to three controlled light regimes (790, 620, and 450 lx). Leaf anatomical traits were assessed via histological sectioning and microscopic imaging. Antioxidant enzyme activities (CAT, POD, and SOD), membrane lipid peroxidation (MDA content), osmoregulatory substances, and carbon metabolites were quantified using standard biochemical assays. Transcriptomic profiling was conducted using Illumina RNA-seq, with differentially expressed genes (DEGs) identified through DESeq2 and functionally annotated via GO and KEGG enrichment analyses. Results: Moderate light (620 lx) promoted optimal leaf structure by enhancing palisade tissue development and epidermal thickening, while reducing membrane lipid peroxidation. Antioxidant defense capacity was elevated through higher CAT, POD, and SOD activities, alongside increased accumulation of soluble proteins, sugars, and starch. Transcriptomic analysis revealed DEGs enriched in photosynthesis, monoterpenoid biosynthesis, hormone signaling, and glutathione metabolism pathways. Key positive regulators (PHY and HY5) were upregulated, whereas negative regulators (COP1 and PIFs) were suppressed, collectively facilitating chloroplast development and photomorphogenesis. Trend analysis indicated a “down–up” gene expression pattern, with early suppression of stress-responsive genes followed by activation of photosynthetic and metabolic processes. Conclusions: A. kusnezoffii employs a coordinated, multi-level adaptation strategy under moderate light (620 lx), integrating leaf structural optimization, enhanced antioxidant defense, and dynamic transcriptomic reprogramming to maintain energy balance, redox homeostasis, and photomorphogenic flexibility. These findings provide a theoretical foundation for optimizing artificial cultivation and light management of alpine medicinal plants. Full article

Combined abiotic stresses often impose greater challenges to plant survival than individual stresses. In this study, we focused on elucidating the physiological and molecular mechanisms underlying the response of Dendrobium huoshanense to combined salt and heat stress by integrating physiological, transcriptomic, and metabolomic analyses. Our results demonstrated that high temperature plays a dominant role in the combined stress response. Physiological assays showed increased oxidative damage under combined stress, accompanied by significant activation of antioxidant enzyme systems (SOD, POD, CAT). Metabolomic analysis revealed significant enrichment of glutathione metabolism and flavonoid biosynthesis pathways, with key antioxidants such as glutathione and naringenin chalcone accumulating under combined stress. Transcriptomic data supported these findings, showing differential regulation of stress-related genes, including those involved in reactive oxygen species scavenging and secondary metabolism. These results highlight a coordinated defense strategy in D. huoshanense, involving both enzymatic and non-enzymatic antioxidant systems to maintain redox homeostasis under combined stress. This study provides novel insights into the molecular mechanisms underlying combined stress tolerance and lays the foundation for improving stress resilience in medicinal orchids. Full article