Search Results (3,807)

Biosurfactants are surface-active microbial molecules with increasing industrial relevance as sustainable alternatives to synthetic surfactants. Among them, lipopeptides produced by Bacillus species, particularly surfactin, exhibit strong interfacial activity and biological functionality. In this study, rhizospheric soils from the La Araucanía region, Chile, were explored as a source of biosurfactant-producing bacteria. Eighteen strains were isolated, and two high-performing strains, Solo 1 and Solo 4, were identified as Bacillus amyloliquefaciens and Bacillus subtilis, respectively. Both strains harbored the srfAA gene and produced surfactin isoforms confirmed by MALDI-TOF MS. Kinetic analysis revealed distinct production profiles, with Solo 1 reaching a maximum of 90 mg L⁻¹ at 24 h, whereas Solo 4 showed continuous production up to 224.4 mg L⁻¹ at 72 h. Both biosurfactants exhibited high emulsification capacity (>80%) and stability across wide ranges of temperature, pH, and salinity. Importantly, cell-free supernatants from both strains showed antibacterial and antibiofilm activity against Staphylococcus aureus, with Solo 4 reaching 81% biofilm inhibition. In addition, surfactin-enriched extracts inhibited the pathogenic bacterium Pseudomonas syringae and the filamentous fungus Fusarium oxysporum, with Solo 4 consistently showing stronger antimicrobial performance. Overall, these findings identify Solo 4 as a promising native Bacillus strain for future development of biosurfactant-based systems aimed at antimicrobial control, biofilm management, agricultural pathogen suppression, surface sanitation, and environmentally compatible biotechnological processes. Full article

Background/Objectives: Tuberculosis (TB), caused by Mycobacterium tuberculosis complex, remains a major global health challenge. Recently, D-enantiomer of human lactoferricin 1–11 (D-form hLF 1–11), a short peptide derived from the N-terminal region of lactoferrin, has demonstrated potent antimycobacterial activity. However, its direct mechanism of action has not yet been elucidated. Methods & Results: In the present study, M. smegmatis was employed as a model organism to investigate the mechanism underlying D-form hLF 1–11 activity. Initially, the minimum inhibitory concentration (MIC) was determined and the results revealed growth inhibition at 400 µg/mL. Live/dead fluorescence staining demonstrated mycobactericidal activity, as indicated by increased propidium iodide (PI) uptake relative to the untreated control. Scanning electron microscopy and high-resolution fluorescence microscopy revealed membrane disruption and substantial morphological deformation, along with a time-dependent accumulation of the peptide at the membrane and inside the cells. Furthermore, label-free quantitative proteomic analysis of peptide-treated cells revealed extensive metabolic alterations in carbon metabolism, acetyl-CoA-dependent lipid biosynthesis, oxidative stress defense, translational machinery, and energy production systems. Conclusions: Collectively, these findings provide mechanistic insights into the antimycobacterial activity of D-form hLF 1–11 against M. smegmatis. Full article

Background: In locally advanced squamous cell esophageal cancer, concurrent chemoradiotherapy (CRT) is the standard of care, as it especially improves local control and overall survival compared to radiotherapy alone. In contrast, treatment strategies for esophageal adenocarcinoma often parallel those used in gastric cancer, particularly regarding systemic therapy. Objectives: This study aimed to evaluate the clinicopathological factors affecting event-free survival (EFS) and overall survival (OS) following trimodality treatment in patients with non-metastatic esophageal cancer. Methods: A total of 155 patients diagnosed with esophageal cancer between March 2019 and November 2025 were retrospectively analyzed. Response to concurrent chemoradiotherapy was assessed via thoracic magnetic resonance imaging and endoscopic biopsy. Results: Clinicopathological analysis showed that male sex, the presence of lymphovascular invasion, adenocarcinoma histology, poor pathological response and advanced-stage tumors were significantly associated with worse EFS (all p < 0.001). In multivariate analysis, stage IVa disease was identified as an independent predictor of both mortality and relapse, with an approximately five-fold increased risk of death (p = 0.028) and relapse (p = 0.019). Patients with squamous cell carcinoma had a longer median EFS compared to those with adenocarcinoma (18 vs. 8.4 months, respectively). The 3- and 5-year OS rates were 59.2% and 56% in patients with squamous cell carcinoma, compared with 40% and 26% in those with adenocarcinoma, respectively. Conclusions: Survival outcomes were more favorable in patients with squamous cell histology and those diagnosed at an early stage. Active surveillance may be considered in selected patients with a complete clinical response to avoid the perioperative mortality associated with surgery. Full article

More specific targeted drug delivery systems with low immunogenicity and toxicity are expected to increase the efficacy of therapeutic molecules. The extracellular nanovesicles have been introduced as natural delivery systems for therapeutic molecules. More recently, considerable interest has emerged in plant-derived exosomes and their natural commitment to deliver molecules of various origins. Acridine Orange (AO) is an acidophilic dye with a strong tumoricidal action following excitation with a light source at 466 nm, but its clinical use is limited by the potential systemic toxicity. In this study we investigated the ability of exosomes from Citrus Sinensis to be successfully uploaded with AO (Exo-AO). We also studied the ability of the exosomes to be uploaded into target cells, as compared to the free molecules. We found that AO was efficiently uploaded into exosomes through electroporation. In fact, Exo-AO entered into the target cells significantly better than the free molecules, leading to both a marked intracellular AO delivery into target cells and an increase in the cytotoxic effect after excitation under a fluorescence microscope. This study shows a promising new approach for a more effective and less toxic drug delivery through the use of plant-derived extracellular nanovesicles. Full article

Scaffolds designed for mechanically demanding soft tissue engineering applications should integrate mechanical support, efficient mass transfer, and good cellular compatibility. This work presents a one-pot method based on “radical-free click chemistry + carbodiimide coupling” to produce a double-network (DN) PEG–alginate cryogel. The PEG network is formed by a Michael addition reaction between thiol-based crosslinker and 8-arm PEG-acrylate. The second network is covalently crosslinked through EDC/NHS-mediated coupling of carboxyl groups in alginate and adipic acid dihydrazide (AAD). The subsequent freezing and gelation of the gel precursor at sub-zero temperatures results in an ice templated cryogel with an interconnected macroporous network. These cryogels demonstrate high elasticity, compressive modulus and rapid swelling equilibrium in aqueous environments, as well as controlled degradation under physiological conditions. Compared to the classical Ca²⁺ ion crosslinking systems, the covalent linking of the alginate in the double-network cryogel shows advantages in mechanical and structural stability. In addition, it is cell-compatible and allows culture of mesenchymal stem cells (MSCs) with homogeneous infiltration. Furthermore, the double-network cryogels supports chondrogenic differentiation of MSCs upon treatment with chondrogenic media or macrophage-conditioned media for a short period of time. These results indicate that crosslinking chemistry and polymer composition can be used to modulate the balance between mechanical performance and degradation behavior, while maintaining cytocompatibility and an interconnected macroporous network, thereby providing a scaffold design strategy for applications that require coordinated mechanical support and mass transfer, such as cartilage-related tissue engineering. Full article

Mitochondrial electron transport chain (ETC) dysfunction is a major driver of bioenergetic failure, redox imbalance, and drug toxicity, yet strategies to restore oxidative phosphorylation under ETC blockade remain limited. Redox-active small molecules could, in principle, shuttle electrons from NADH to distal ETC components and oxygen, thereby modulating both respiration and reactive oxygen species (ROS) formation. Here, we show that the enzyme-independent redox cycler phenazine methosulfate (PMS) rewires mitochondrial redox circuits and restores respiration in human glioblastoma cells and cell-free systems under ETC inhibition. At subtoxic concentrations, PMS acutely increased oxygen consumption and mitochondrial superoxide generation via NADH–PMS–O₂ redox cycling, while restoring mitochondrial membrane potential and ATP synthesis under ETC blockade, and shifting metabolism away from glycolytic lactate production. This profile is consistent with a protective redox-bypass role, distinct from the pro-apoptotic effects reported following high-dose, prolonged PMS exposure. The PMS-driven restoration of electron flow, mitochondrial membrane potential, and respiratory ATP synthesis under inhibition of Complex I (rotenone), III (antimycin A and myxothiazol), and/or IV (cyanide) is consistent with direct cytochrome c reduction, as demonstrated herein, and engagement of multiple ETC redox centers, including coenzyme Q₁₀. In metformin-treated cells, PMS reversed suppression of respiration and lactate accumulation, outperforming existing redox-bypass strategies. These findings identify PMS-driven redox cycling as a previously unrecognized chemical redox-bypass mechanism that both regenerates mitochondrial bioenergetics and reshapes ROS production, suggesting a potential approach to counteract drug- and toxin-induced mitochondrial dysfunction and to exploit redox vulnerabilities in cancer. Full article

The removal of heavy oil under low-temperature conditions is a significant global challenge. This study aimed to assess the long-term whole-cell biocatalytic degradation of heavy oil in water and soil by bacteria isolated from contaminated soil in Muroran, Japan, under cold conditions. Enrichment cultures using heavy oil as the sole carbon source yielded 15 potent heavy oil-degrading isolates. However, only the C1 strain retained its activity under low-temperature conditions and was identified as Pseudomonas aeruginosa C1 using 16S rDNA sequencing. Gas chromatography analysis revealed that at 30 °C (water medium), strain C1 degraded 57% of heavy oil within 7 days. At 15 °C, the degradation efficiency of C1 declined due to a temperature-dependent metabolic lag phase (1 day); however, at 15 °C, 70% degradation was observed in seven days. In long-term experiments at 5 °C and 10 °C, 35% and 40% degradation were recorded for C1 after 98 days. In artificially contaminated soil at 5 °C, C1 achieved 60% biodegradation. These results demonstrate cold-adapted whole-cell activity against heavy oil and motivate the design of controlled, contained ex situ reactors (e.g., enzyme-based or cell-free systems) for safe remediation in cold climates. Full article

Lactic acid bacteria (LAB) have been widely utilized in the production of fermented foods worldwide due to their well-established health-promoting benefits for both humans and animals. In addition to their nutritional value, LAB exhibit antagonistic activity against foodborne pathogens, particularly Salmonella spp., which are commonly associated with livestock and animal production systems. LAB exert a range of biological effects that can inhibit the growth of Salmonella and modulate its virulence. In the present study, the antagonistic potential of Weissella confusa WM36 was evaluated based on its ability to inhibit S. Typhimurium growth, disrupt biofilm formation, and suppress the expression of virulence-associated genes. A preliminary safety assessment of W. confusa WM36 was conducted through hemolytic activity and antibiotic susceptibility profiling. In addition, the biofunctional properties of its cell-free supernatant (CFS), herein referred to as postbiotic metabolites, were investigated with a particular focus on antioxidant activity. Experimental results demonstrated that W. confusa WM36 and its CFS at 40% (v/v) achieved a complete reduction (100%) of S. Typhimurium cell counts within 6 to 12 h of treatment. Furthermore, CFS at 20% and 40% (v/v) significantly impaired biofilm formation, while treatment with 20% (v/v) CFS markedly downregulated the expression of key virulence genes. The strain WM36 exhibited α-hemolytic activity and showed susceptibility to most of the antibiotics tested, although resistance to ceftriaxone and trimethoprim–sulfamethoxazole was observed. These findings provide preliminary information regarding its safety characteristics; however, further molecular and in vivo investigations are required to comprehensively evaluate its safety for practical applications. Additionally, the CFS exhibited notable antioxidant activity, with DPPH radical scavenging capacity of 8.90 ± 0.06 mM Trolox equivalents and ABTS radical scavenging power of 13.10 ± 1.42 mM Trolox equivalents. Collectively, these findings highlight the potential of W. confusa WM36 and its postbiotic metabolites as promising biocontrol and functional agents against S. Typhimurium, while further safety validation remains necessary. Full article

This study reports the plant-mediated synthesis of copper-oxide-decorated magnetic iron oxide composite (CuO@Fe₃O₄) nanoparticles using Dolomiaea costus extract and their application as nanocarriers for β-galactosidase immobilization. The fabricated nanocomposite exhibited favorable physicochemical properties, achieving an immobilization efficiency of 83%, with enhanced thermal and pH tolerance compared to the free enzyme. Kinetic analysis revealed a modest increase in Km and a 31% decrease in Vmax after immobilization, while maintaining 69% of the catalytic activity, confirming the system’s suitability for industrial lactose hydrolysis. Reusability and storage tests showed 79% retained activity after five cycles and 77% after 60 days at 4 °C. In milk hydrolysis, the immobilized enzyme achieved 77% conversion within 3 h, following pseudo-first-order kinetics. Biocompatibility was evaluated using HepG2 cells via the MTT assay. BDH, MDH, and ABC maintained high cell viability across the tested dilution range of 25–100% (v/v), indicating no detectable cytotoxic effect under the experimental conditions, whereas cisplatin showed marked cytotoxicity with an IC₅₀ of 14.98 µg/mL. These findings demonstrate that the green-synthesized CuO@Fe₃O₄ support provides a safe, reusable, and magnetically recoverable platform for β-galactosidase immobilization, offering a promising sustainable strategy for producing lactose-free dairy products. Full article

The scaffold protein RACK1 (Receptor for Activated C Kinase 1) integrates signaling and translation, acting as a core component of the 40S ribosomal subunit. It binds activated Protein Kinase C (PKC) isoforms and membrane receptors. We used an auxin-inducible degron (AID2) system in human HAP1 cells to selectively deplete the free (cytoplasmic) pool of RACK1. The engineered RACK1–mAID–mClover3 fusion was rapidly degraded in the cytoplasm upon addition of 5-phenyl-indole-3-acetic acid (5-Ph-IAA), while the ribosome-bound pool remained detectable in ribosomal fractions, indicating that ribosome association makes RACK1 relatively less accessible to AID2-mediated proteolysis. Upon activation of PKCβII with phorbol-12-myristate-13-acetate (PMA), imaging at defined time points revealed closely matched kinetics of PKCβII membrane recruitment and membrane-proximal enrichment of ribosome-bound RACK1, peaking at ~10 min. Our data support a model in which activated PKCβII engages ribosome-bound RACK1 at membrane-proximal sites, consistent with a diffusion–capture mechanism in which PKCβII first accumulates at the membrane and then captures ribosome-bound RACK1, thereby recruiting the translational machinery to sites of signal input for membrane-proximal translation. These findings provide new insights into the spatial organization of translation. Full article

Tissue engineering and regenerative medicine (TERM) rely on advanced biomaterials and scaffolds that require strict sterilization without sacrificing their structural and functional properties. Conventional sterilization methods, including steam, ethylene oxide, and gamma irradiation, often compromise scaffold integrity, alter surface chemistry and/or leave toxic residues. Ozone (O₃) has emerged as a promising alternative sterilant because of its strong oxidizing potential, broad-spectrum antimicrobial activity, and residue-free decomposition. Importantly, ozone sterilization can preserve—and in some cases enhance—scaffold bioactivity by maintaining cytocompatibility and favorable surface chemistries that support cell adhesion and differentiation. This review critically evaluates the role of ozone sterilization in the context of TERM applications, focusing on its physicochemical properties, disinfection kinetics, material compatibility and regulatory perspectives. Evidence from studies on polymethyl methacrylate (PMMA) scaffolds, bone implants, and hydrogel-based systems suggests that, under optimized conditions, ozone can achieve high sterilization efficacy without significant degradation of mechanical or chemical properties. However, challenges related to process validation, health and safety considerations, and scalability remain. The review highlights opportunities for integrating ozone into automated biomanufacturing workflows and identifies key research gaps to support the broader adoption of ozone sterilization in TERM applications. Full article

The ICAM-1-derived cIBR peptide selectively binds to the I-domain of LFA-1, a receptor highly expressed on leukemia T cells; thus, the MTX-cIBR conjugate can be used to target methotrexate (MTX) to leukemic T cells and reduce its off-target toxicity. However, the uptake, biological mechanism, and selectivity of MTX-cIBR compared with unconjugated MTX remain unclear. Therefore, this study is aimed at evaluating the uptake, cytotoxicity, selectivity, apoptosis, cell cycle effects, and DHFR-related activity of MTX-cIBR in leukemia T cells compared with unconjugated MTX. MTX-cIBR exhibited cytotoxic activity comparable to MTX in LFA-1-expressing MOLT-4 cells but showed lower toxicity toward LFA-1-negative K562 cells, indicating improved selectivity. MTX uptake occurred through RFC and mFBP transport systems, whereas MTX-cIBR no longer depended on these pathways, suggesting altered cellular uptake after conjugation with cIBR by utilizing the LFA-1 receptor. Both compounds predominantly induced apoptosis with minimal necrotic cell populations. MTX induced S-phase arrest at lower concentrations and G2/M induced arrest at higher concentrations, whereas MTX-cIBR consistently promoted S-phase accumulation. In addition, MTX and MTX-cIBR downregulated the expression of DHFR, FPGS, and TYMS in MOLT-4 cells. Computational analyses further demonstrated that MTX exhibited lower binding free energy (ΔG) and greater binding stability toward DHFR than MTX-cIBR. These findings suggest that MTX-cIBR retains selective cytotoxic activity toward LFA-1-expressing leukemia T cells through altered cellular uptake and exhibits different interaction characteristics with DHFR compared with unconjugated MTX. Full article

Background: Pulmonary tuberculosis (TB) is a significant trigger of acute exacerbations of chronic obstructive pulmonary disease (AECOPD), so its timely and accurate diagnosis is essential. Also, the risk factors for TB occurrence in this population remain unclear. This study aimed to evaluate the performance of metagenomic next-generation sequencing (mNGS) for TB diagnosis in AECOPD patients, as well as to identify the associated risk factors. Methods: A retrospective observational cohort of 659 AECOPD patients with suspected pulmonary infection was enrolled. The microbial cell-free nucleic acids in bronchoalveolar lavage fluid samples were extracted and subjected to mNGS detection. The clinical data for each patient were collected from the hospital information system. The statistical analyses were performed with SPSS version 25.0. Results: A total of 170 cases, included for final analyses, were categorized into TB (n = 41), bacterial infection (n = 73), and non-infective control (n = 56) groups. Among these groups, the TB group had the highest intensive care unit (ICU) admission rate (46.34%) and longest median hospital stay (19.50 days) (p < 0.01). For TB diagnosis, mNGS demonstrated a greater sensitivity (86.00%), a lower specificity (93.30%), and a higher area under the curve (AUC, 0.877) than TB-DNA detection (70.21%, 100%, 0.848, respectively) and Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) assay (63.83%, 100.00%, 0.870, respectively). Notably, mNGS identified the bacterial or viral co-infections in 18.00% of TB cases. Furthermore, the stringently mapped read number determined by mNGS showed a positive correlation with ICU admission rate (r = 0.76) and in-hospital mortality (r = 0.77). The lower body mass index (BMI) and reduced natural killer (NK) cell count were identified as the independent risk factors in the TB group (both p < 0.05). Conclusions: For the diagnosis of pulmonary TB in AECOPD patients, mNGS demonstrated comparable performance to TB-DNA detection and Xpert MTB/RIF assay, and also mNGS identified co-infections. In addition, a lower BMI and reduced NK cell count were identified as the independent risk factors for TB occurrence in this cohort. Full article

Background/Objectives: Chronic microenvironment stress contributes to the progression of melanoma, yet practical tools for quantifying tumor stress adaptation remain limited. Methods: Using disulfiram as a system-level probe, we identified shared regulatory modules between disulfiram-related targets and melanoma-associated genes, which are integrated into pathways regulating apoptosis and hypoxia/oxidative stress. From these modules, we devised a stress adaptation score (BiScore) based on hallmark gene characteristics and assessed its prognostic significance in melanoma cohorts. Results and Conclusions: In the TCGA-SKCM dataset, a higher binuclear score correlated with poorer overall survival and remained an independent prognostic factor even after adjusting for clinical covariates. This observation was externally validated for distant metastasis-free survival rate in the GSE65904 cohort. Tumors with high binuclear expression consistently exhibited reduced immune infiltration and were weakly associated with mutation load, suggesting that the stress adaptation axis operates independently of gene mutation burden. Single-cell analyses demonstrated that stress-related signals were distributed across both malignant and stress-responsive microenvironmental compartments. In melanoma cell lines, hypoxia induces HIF-1α expression and shifts apoptosis-related proteins towards an anti-apoptotic state, and NAC attenuated CoCl₂-induced ROS accumulation. In conclusion, these findings establish BiScore as a quantitative framework for capturing stress adaptation states linked to adverse outcomes in melanoma. Full article

Three-dimensional (3D) cell culture models more faithfully reproduce native tissue organization and function than conventional two-dimensional systems, yet many existing bioprinting methods depend on scaffolds, complex instrumentation, or limited control over cell positioning. This review examines magnetic bioinks as a versatile platform for contactless 3D cell manipulation and biofabrication. It first outlines the fundamentals of magnetophoresis and defines magnetic bioinks as combinations of magnetic agents, including magnetic nanoparticles or paramagnetic salts, with biological components such as cells, proteins, or fluids. The review then compares label-based strategies, in which cells are magnetized and guided by positive magnetophoresis, with label-free approaches that exploit magnetic susceptibility differences to position diamagnetic cells through negative magnetophoresis. Across these methods, magnetic bioinks have enabled single-cell sorting, spatial patterning, spheroid and co-culture assembly, multilayer tissue formation, and hydrogel-integrated printing. These capabilities support applications in disease modeling, drug screening, biosensing, regenerative medicine, and emerging biofabrication under microgravity conditions. The paper also highlights key limitations, including nanoparticle biocompatibility, paramagnetic salt toxicity, osmotic stress, and the need for better assay standardization and translational validation. Overall, magnetic bioinks represent a promising scaffold-free approach for rapidly producing physiologically relevant 3D biological constructs for research and clinical innovation. Full article