The salmonid aquaculture industry faces increasing challenges associated with the expansion of intensive production systems, particularly infectious diseases. To mitigate these issues, the Norwegian industry is progressively shifting towards land-based production systems, which reduce the grow-out phase at sea and associated pathogen exposure. However, such infrastructures provide extensive surfaces that may facilitate biofouling and bacterial persistence. In this study, we investigated the occurrence and diversity of Tenacibaculum spp. in a Norwegian land-based Atlantic salmon ( Salmo salar ) facility from September to December 2024, by screening both fish and environment samples. Bacterial isolation and multilocus sequence analysis (MLSA) revealed a temporal shift in Tenacibaculum species composition with opposite dynamics of T. maritimum and T. dicentrarchi . T. maritimum was predominantly detected in September and was associated with mortality during an ulcerative disease outbreak, whereas T. dicentrarchi was mainly isolated in December from fish ulcers and structural elements of the facility. The repeated isolation of Tenacibaculum strains from both fish and infrastructure suggests that land-based systems may enable persistence and reinfection by biofilm-forming bacteria, highlighting the need for systematic surveillance. Furthermore, recurring summer heat waves in Norway in association with global warming may help the expansion of T. maritimum . This study provides the first documented evidence of T. maritimum infecting Atlantic salmon in Norway. • Seasonal shift in Tenacibaculum species in a Norwegian land-based salmon facility • Opposite seasonal dynamics of T. maritimum and T. dicentrarchi • Land-based systems can facilitate biofilm-forming bacteria persistence • First report of T. maritimum infecting Atlantic salmon in Norway

Biofilm-associated prosthetic joint infections (PJIs) are becoming an increasing public health concern due to their ability to form biofilm on prosthetic implants and cause significant morbidity owing to antibiotics resistance. Therefore, new drugs and management procedures are required to improve the treatment outcome for PJIs and the drug repurposing is an excellent method to develop new antimicrobials. Thus, the present study evaluated etoricoxib, a selective COX2 inhibitor for its antibacterial and antibiofilm activities against Staphylococcus aureus - one of the major biofilm-forming bacteria causing the PJIs. The anti-S. aureus potential of etoricoxib was analyzed and the minimum inhibitory concentration (MIC) was found to be as low as 25µg/mL. The killing-kinetics of etoricoxib was observed at 2h and the drug showed synergistic effect along with ampicillin and tetracycline, reducing the MIC by 4-fold. Further, etoricoxib exhibited antibiofilm activity by inhibiting biofilm formation and displaying mature biofilm eradication by 90% after the treatment. To prevent biofilm formation on implant material, etoricoxib was coated on the implant material and it reduced 80% of bacterial attachment which was further confirmed by FDA/PI staining that revealed 79% of dead cells on the coated material. The docking analysis revealed the strong binding affinity of etoricoxib towards bacterial biofilm adhesion proteins and the drug downregulated the biofilm adhesion protein encoded genes namely icaA, clfA, cna, fnbA, and fib expression levels after the treatment. Moreover, etoricoxib treatment caused S. aureus cell damage resulting in cell death and was noticed through scanning electron microscope (SEM) analysis. Thus, as etoricoxib was effective in eliminating and preventing biofilms and the authors recommend further in vitro and in vivo studies to explore the possibility for new therapeutic option for implant-associated infections.

Synthetic microbial communities reveal the mechanisms of fungus-bacterium metabolic interactions regulating exopolysaccharide production in Viili.

The American cranberry, Vaccinium macrocarpon, has been reported to benefit human health and is a popular remedy for self-treatment of urinary tract infections. Cranberry proanthocyanidins have been shown to inhibit growth and biofilm formation of oral pathogens and dental plaque bacteria associated with dental caries and periodontal disease. To evaluate the hypothesis that short term in vivo exposure to cranberry juice inhibits metabolic activity of human dental plaque bacteria the Plaque Glycolysis and Regrowth method (PGRM) was used. Two independent randomized crossover trials were conducted: one in adults (18-64 years, N = 8) and one in children (7-12 years, N = 14). Commercially marketed Ocean Spray® unsweetened pure 100% cranberry juice (CJ-100) and cranberry juice cocktail (CJC-27, 27% juice with added sugar) were used. Water was used as control. Overnight fasting supragingival plaque from buccal and lingual surfaces in the left maxillary and mandibular quadrants were collected using a sterile cotton swab (Pre-exposure). Participants then rinsed and consumed 10ml of CJ-100 or CJC-27 within 30s for three consecutive times. After 30min, their right maxillary and mandibular plaque were collected (Post-exposure). The acid production and regrowth of all plaque samples were assessed and data between the Pre- and Post-exposure plaque samples were compared. Data from each study were analyzed separately.Compared to the pre-exposed controls, consumption of CJ-100 reduced average regrowth and acid production of plaque bacteria in adults (43.93 ± 19.67%; ΔpH: 0.56 ± 0.25) and in children (33.04 ± 23.88%; ΔpH: 0.36 ± 0.24). No significant inhibition was noted after exposure to CJC-27 or water. In vivo exposure of adult and children's dental plaque to pure cranberry juice reduces subsequent metabolic activity, including regrowth and acid production. Cranberry juice may offer a healthier alternative to popular sugary beverages. PGRM represents a potential efficacy screening tool for natural or food-based antiplaque agents.

SUMMARYUrinary tract infections (UTIs) are among the most common bacterial infections worldwide, with catheter-associated UTIs (CAUTIs) representing a major subset in healthcare settings. CAUTIs significantly increase patient morbidity, mortality, hospital stays, and healthcare costs, while driving antibiotic overuse and antimicrobial resistance (AMR). Systemic antibiotics often fail due to poor biofilm penetration, localized infection sites, and rising multidrug resistance, highlighting the urgent need for alternative, targeted therapies. This review discusses the role of intravesical therapies in both the treatment and prevention of CAUTIs, with a primary emphasis on therapeutic applications. The bladder is an accessible target for local treatment, as catheters can be repurposed for drug delivery. These devices are frequently colonized by biofilm-forming bacteria that contribute to persistent infection and treatment failure. This review explores intravesical therapy, the direct instillation of antimicrobial agents into the bladder, as a promising strategy to improve CAUTI management and mitigate AMR. We examine CAUTI pathogenesis, biofilm development, and current clinical approaches, including antimicrobial stewardship, catheter management, and coating technologies. Evidence for intravesical antibiotics such as gentamicin, amikacin, colistin, fosfomycin, and trimethoprim is reviewed alongside limited data from clinical trials, and applications in other urological disorders. Non-antibiotic alternatives, including sterile saline, antiseptic solutions, bacteriophages, antimicrobial peptides, natural bioactives, probiotics, and silver nanoparticles, are also discussed, particularly for their potential synergistic use with antibiotics to reduce resistance emergence. Despite encouraging results, intravesical therapy faces challenges such as limited clinical data, lack of standardized protocols, and delivery barriers. This review summarizes current evidence, identifies research gaps, and proposes directions to advance this underused strategy against CAUTIs amid escalating antibiotic resistance.

This study investigated the chemical composition and antibacterial and antibiofilm activities of Cymbopogon flexuosus essential oil (CFEO) against multidrug-resistant (MDR) bacteria within a One Health framework. The bacterial panel comprised four clinical isolates (n = 1 per source): a methicillin-resistant Mammaliicoccus sciuri (MR-M. sciuri) from bovine mastitis, a colistin-resistant ESBL-producing Escherichia coli (E. coli) from avian colibacillosis, and MR-Staphylococcus haemolyticus (MR-S. haemolyticus) and MDR Staphylococcus aureus (MDR S. aureus) from healthy farm personnel in contact with diseased animals. GC-MS analysis was performed to study the chemical composition of the CFEO. Antibacterial activities were evaluated via disk diffusion and broth microdilution assays. Disk diffusion was used exclusively as a qualitative screening tool to identify potential interactions; synergy was assessed definitively through the checkerboard assay by calculating the Fractional Inhibitory Concentration Index (FICI). The antibiofilm activity of CFEO was quantified via Congo red agar, crystal violet staining, and light microscopy. Molecular docking simulation was performed to assess the binding interactions of the CFEO constituents with key bacterial proteins. The major constituents of CFEO were geranial (α-citral; 32.98%), neral (β-citral; 28.62%), β-terpinene (11.50%), geraniol (5.42%), nerol acetate (3.40%), and linalool (2.31%). The inhibition zones ranged from 38 ± 2.00 to 56 ± 1.00mm, while the MIC values spanned from 8 to 8192µg/mL. CFEO demonstrated a synergistic effect with oxacillin against MR-M. sciuri (FICI = 0.28). Sub-MIC concentrations of CFEO significantly disrupted the biofilms of M. sciuri and E. coli. Bioinformatics analysis via molecular docking revealed favorable binding affinities between major compounds of CFEO and key bacterial proteins, including PBP2a, SarA, and AgrA. This study highlights the in vitro efficacy of CFEO against MDR, MR and biofilm-forming bacteria circulating at the animal-human interface, as well as its synergistic potential when combined with oxacillin against MR-M. sciuri. Molecular docking analyses suggest that the major compounds of CFEO may act as promising adjuvants in the development of new therapeutic strategies against MDR bacteria within a One Health framework.

Cadmium (Cd) and polystyrene (PS) microplastic co-contamination in agricultural soils poses a potential threat to food security. Some functional microorganisms in soil can alleviate the dual stress of Cd and PS on crops. In this study, a biofilm-forming bacterium, Enterobacter sp. W5, was isolated from heavy metal-contaminated rhizosphere soil. Strain W5 exhibited Cd removal efficiency (46.3%) and strong biofilm-forming capacity (OD570 = 5.05), and it effectively colonized PS microplastic surfaces. XPS analysis detected bacterial functional groups (C–O–C, C=O) and PS-associated signals (O–C=O), which may act synergistically in Cd2+ adsorption. Furthermore, XPS and XRD analyses revealed the presence of Cd-containing precipitates (including CdS, CdO, and Cd3(PO4)2). In hydroponic wheat experiments, W5 inoculation alleviated Cd-PS combined stress, thus significantly promoting plant growth and reducing Cd accumulation by 22.6% in roots and by 34.2% in aboveground tissues. Subcellular distribution analysis revealed that W5 enhanced Cd retention in root cell walls, thereby limiting its translocation to active cellular compartments. Proteomic analysis identified a set of 11 consistently downregulated proteins, including A0A3B6HQ68 and A0A3B6KJV9, which were enriched in secondary metabolite biosynthesis pathways. Bioinformatic analysis suggests that these proteins may be associated with Cd stress responses, though their exact roles remain to be verified. Collectively, this study provides a valuable microbial resource and mechanistic insights into the application of biofilm-forming bacteria for mitigating combined heavy metal–microplastic pollution in agricultural systems.

Hospital-acquired resistant infections (HARI) are difficult to manage due to limited treatment options and their ability to withstand stress conditions through biofilm production. HARI were defined as infections occurring at least 48h after hospital admission. This work aimed to assess the distribution of HARI-associated bacterial species in north Israel and to investigate associations between biofilm formation and extended-spectrum β-lactamase(ESBL) genes, bacterial and patient characteristics, and hospitalization length, season and year. Methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) and Acinetobacter baumannii (A. baumannii), ESBL-producing Escherichia coli (ESBL-E. coli), Klebsiella pneumoniae (ESBL-K. pneumoniae) and Proteus mirabilis (ESBL-P. mirabilis) were isolated from 569 blood, urine, wound and respiratory samples of hospitalized patients with HARI during 2020-2022 in north Israel. Enterobacterales were included if ESBL-positive (Vitek 2 and disc tests), and Acinetobacter and Pseudomonas if resistant to ≥ 3 antibiotic families. Biofilm-formation capacity was assessed by the crystalline violet method. ESBL genes were detected by real-time PCR. Data regarding season, time to infection, bacterial species, patient demographics, year, and hospital department, were collected from medical records. ESBL-K. pneumoniae was the most prevalent (31.6%) bacteria. Strong biofilms were produced by 346 (60.8%), most of the strong biofilm producers were K. pneumoniae, accounting for 160 out of 346 strong-biofilm isolates (46.2%). blaCTX-M was the most commonly detected ESBL gene (87.7%). Most strains (61.2%) carried more than one ESBL gene. Hospitalization season had a notable impact on biofilm production, with a heightened risk of infection by robust biofilm producers during spring, summer and autumn compared to winter. Furthermore, the presence of blaSHV and blaTEM genes were significantly associated with enhanced biofilm production. Bacteria harboring all three ESBL genes exhibited the highest biofilm production capacities, compared to those carrying fewer than three. Biofilm-production intensity differs across bacterial species and seasons and is influenced by the presence of ESBL genes.

Background: A compact, in-house-developed ultraviolet germicidal irradiation (UVGI) system using eight 36 W Philips low-pressure mercury UV-C lamps with a peak emission at 253.7 nm was developed for effective sterilization of bacteria and fungi using a wireless mode of operation. Methods: Under controlled laboratory conditions, the system was tested against representative biofilm-forming microorganisms, including Bacillus subtilis, Escherichia coli K12, and a multidrug-resistant Candida albicans M-207 isolate. Microbial viability was assessed using colony-forming unit (CFU) enumeration and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, with structural changes analyzed by scanning electron microscopy (SEM). Cultures were exposed to 253.7 nm UV-C radiation at distances of 1–5 m for 15–90 min. Results: UV-C exposure resulted in time- and distance-dependent reductions in viable counts for all tested organisms, as determined by CFU analysis. At 1 m and 15 min exposure, viable counts for all tested organisms were reduced below the limit of detection (LOD) of the CFU assay, indicating substantial microbial inactivation under the tested conditions. Reduced efficacy was observed at increased distances (3 m and 5 m), with log10 reductions varying depending on organism and exposure conditions. Residual metabolic activity detected by the MTT assay suggests the presence of non-proliferating or damaged cells, consistent with the different endpoints measured by the two assays. The SEM analysis further revealed disruption of biofilm architecture and reduction in cell density with increasing UV dose. Conclusions: The UVGI system demonstrated dose-dependent inactivation of biofilm-forming microorganisms under controlled conditions, supporting its proof-of-concept efficacy. Further studies are required to evaluate performance under real-world conditions.

Osteomyelitis remains a persistent healthcare concern due to bacterial invasion and difficulty in inhibiting and eradicating biofilm-forming bacteria from infected bone tissue. Conventional therapies, including systemic antibiotics and surgically implanted beads made of calcium sulfate or polymethyl methacrylate, are hindered by complications like cytotoxicity, uneven drug distribution, and thermal denaturation of antibiotics during polymerization. Here, a solvent-free droplet approach is introduced for producing ready-to-use antibiotic-loaded beads through controlled aggregation of pre-formed polymer latex nanoparticles composed of poly (methyl methacrylate-co-butyl acrylate) [P(MMA-BA)]. Calcium chloride, a benign coagulant, triggers the controlled aggregation of latex nanoparticles and enables bead formation without the need for hand-mixing, chemical initiators, and solvents used in the existing PMMA bead fabrication method. Ampicillin was incorporated as a model antibiotic to evaluate antimicrobial and biocompatibility performance. The resulting beads demonstrated prolonged antibacterial activity and strong inhibition of Staphylococcus aureus biofilms. In co-culture systems with osteoblast Saos-2 cells, the beads selectively inhibited bacterial growth while maintaining cell viability, confirming their dual antibacterial and cytocompatibility functions. In vivo evaluations further supported their effectiveness in infection control and tissue integration. Overall, these results highlight the potential of latex particle-assembled polymeric beads as a scalable, solvent-free, and efficient platform for targeted bone infection treatment.

Diurnal temperature fluctuations are common in soil during the dry winter season in the Eastern sub-Himalayan Terai region (Cwa climatic zone, according to Köppen's classification). The difference between the evening and morning temperatures of 5-6°C results in 70-75% vigor loss due to electrolyte leakage from the seeds, thereby extending the nursery period. Therefore, it is essential to minimize soil thermal fluctuations to retain seed vigor. In this study, we utilised biofilm-forming bacterial species like Phytobacter, Priestia, and Bacillus as bioinoculants and aimed to elucidate how they buffer soil temperature fluctuations. Since the highest fluctuations in soil temperatures occur in the cold, dry winter season, it was hypothesised that using biofilm-forming microbes as seed coatings could prevent desiccation-induced water loss from seeds. We performed in vitro (changing the daily temperature) and in situ experiments (using a Randomized Block Design) to analyze the seed vigor. In vitro assessment of tomato seeds indicates the role of both duration and intensity of cold stress in seed vigor reduction. This loss was recovered with bacterial inoculation (30-100% depending upon the intensity and duration of stress). Vigor recovery was also demonstrated in fields where seeds treated with bacteria displayed better emergence (70-95%). Interestingly, the difference between morning and evening soil temperatures reduced upon bioinoculant treatment (0.8 ± 0.2°C ) as compared to control (2.7 ± 0.9°C) in the rhizosphere developed from seeds treated with biofilm-forming bacteria, demonstrating thermal buffering of rhizospheric soil. Since biofilm have hygroscopic properties, a relatively higher residual moisture was recorded from soils in fields raised from the bio-inoculant-treated seeds. Water, owing to its high specific heat (4.186J g- 1 °C- 1), can buffer temperature fluctuations. This is the first report showing the mechanism of microbe-mediated thermal buffering of rhizosphere. Since these microbes can improve moisture retention during cold, dry winter months, they can be used in areas with comparable climates.

Biofilms on meat-contact surfaces pose critical food safety risks. This study investigates the interplay between biofilm architecture, metabolic vigor, and antimicrobial resistance on retail surfaces in Pakistan. Screening 300 isolates from 120 surfaces identified 42 high-risk biofilm formers. Comprehensive phenotypic screening revealed that standard visual assays severely underestimate the viability of environmental strains. Biofilm biomass and metabolic activity correlated positively (Spearman’s ρ = 0.656, p < 0.001). Crucially, Ordinary Least Squares regression established that metabolic vigor, rather than physical biomass, independently predicts resistance severity. Phenotypic profiling revealed a high-risk landscape with 81.8% multidrug-resistant and 18.2% extensively drug-resistant isolates, including resistance to colistin and Linezolid. Alarmingly, 79.5% of critical resistance phenotypes compromised WHO Reserve category antibiotics, escalating to 100% on mincer machines. Ecological analysis demonstrated surface-driven partitioning; porous wood boards fostered diverse Enterobacteriaceae, while mincers selected for uniformly resistant clades. These findings highlight processing machinery as resilient reservoirs for untreatable pathogens, necessitating targeted anti-biofilm measures, such as matrix-degrading enzymes. Bridging a critical knowledge gap, this study is among the earliest integrated ecological analyses combining phylogenetic, metabolic, and resistance profiling in Pakistan’s non-poultry meat sector.

Six novel azo-compounds derived from α-dicarbonyl species, such as 9,10-phenanthrene quinone, squaric acid and ammonium 2,3,5,6-tetraoxo-4-nitropyridinate, were isolated by reactions with a series of heterocyclic hydrazides and characterized by a set of methods. The spectral studies (FT-IR and 1H NMR), together with theoretical DFT modeling and X-ray structure description, of two compounds revealed the hydrazone tautomeric forms of the molecules. Antimicrobial activity against biofilm-forming bacteria was assessed using a turbidimetric method. Growth inhibition was monitored to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for both Gram-positive and Gram-negative strains. The possibility of a hemolytic effect of the compounds on human red blood cells was evaluated. The ADMET analysis indicated that all the studied compounds obeyed Lipinski's and Veber's rules of the drug discovery pipeline and offered oral bioavailability and positive blood-brain barrier permeability, indicating their potential as therapeutic lead-like compounds. According to the Toxtree analysis, all investigated compounds were categorized as Class I, indicating they belong to the low-toxicity group. The molecular interactions and inhibitory potential underlying the antimicrobial activities of the selected compounds were investigated using molecular docking methods.

To mitigate marine biofouling, copper- and zinc-based antifouling (AF) paints are widely used, although their severe environmental toxicity is well established. Silicone-based fouling-release coatings (FRCs) have emerged as alternatives that prevent adhesion through surface properties rather than biocidal activity. However, their effectiveness and ecological impact across marine environments remain insufficiently assessed. This study compared the performance and environmental effects of five commercial coatings: two biocidal, two FRCs, and one inert coating. Panels were statically exposed for seven months at five European sites spanning salinity and temperature gradients. Fouling development was monitored monthly, and coating leachates were tested on red macroalgae and bacteria. Ecotoxicological assays included growth inhibition of Ceramium tenuicorne, Aliivibrio fischeri bioluminescence, Escherichia coli stress biosensors, quorum-sensing (QS) assays, and biofilm formation of marine bacteria. Field experiments showed that FRCs consistently outperformed copper-based coatings in efficacy toward biofouling, even under static conditions. Copper-based leachates were highly toxic to C. tenuicorne (EC50≈0.46%), whereas FRC leachates showed minimal effects and were about 100 times less toxic. Microbial assays revealed that all coatings-including the biocide-free formulations-altered microbial physiology and behavior: leachates induced protein-damage responses, and both QS signaling and biofilm formation were species-specific, confirming that biocide-free does not mean biologically neutral. These results demonstrate that antifouling leachates act not only as toxicants but also as chemical cues shaping microbial communication and early colonization. Integrating microbial-level responses into antifouling evaluations is therefore essential. Overall, FRCs remain the most environmentally acceptable option, combining strong antifouling performance with minimal toxicity.

Microbial communities inhabiting natural and anthropogenically impacted environments are exposed to diverse abiotic stressors that can influence the distribution of functional traits. However, distinguishing the processes underlying phenotypic patterns remains challenging in microbial systems, where ecological and evolutionary dynamics often overlap. In this study, we experimentally assessed the distribution of biofilm formation and plastic degradation capacity in bacterial isolates across environments characterized by different stress regimes, to evaluate whether these traits are primarily associated with environmental context rather than phylogenetic relatedness, and may therefore reflect environment-dependent phenotypic modulation on a lineage-specific functional background. Taxonomic affiliation was assessed using 16S rRNA gene sequencing, while expressed biochemical profiles were characterized by Fourier-transform infrared (FTIR) spectroscopy. Multivariate ordination and Partial Least Squares analyses were used to explore relationships among taxonomy, biochemical profiles, functional phenotypes, and environment of isolation. Phylogenetic signal analysis confirmed that neither trait was strongly constrained by vertical inheritance, with Blomberg’s K ≈ 0 and Fritz & Purvis’ D = 0.51, consistent with environment-driven rather than phylogenetically conserved trait distributions. Both biofilm production and plastic degradation capacity showed significant environment-dependent differences in their relative frequencies (Fisher’s exact test, biofilm: p = 5.5 × 10−5; PCL degradation: p = 2.5 × 10−4) and were not directly associated with each other (Wilcoxon rank-sum test, p = 0.45; linear model, p = 0.68). Overall, these results indicate that microbial functional traits are unevenly distributed across environments and weakly constrained by taxonomy, consistent with the contribution of multiple, non-mutually exclusive processes that remain difficult to disentangle empirically.

Enhancements of symbiotic adhesion and antibiotic efficacy observed by the metabolic crosstalk within cell-bacteria cocultured on a microfluidic gut chip

Diabetic wounds usually involve disorganized redox and immune homeostasis and are prone to bacterial infection, often leading to delayed healing and worse outcomes. However, existing therapeutic strategies cannot simultaneously achieve potent antibacterial action and temporal microenvironment modulation. Herein, a self-evolving hyaluronan/poly(aspartic acid) hydrogel dressing integrating in situ Ag+-to-Ag nanozyme conversion function and hydrolyzable Fe3N/Fe3O4 nanoheterojunction (nHJ) is presented to meet the intricate requirements of consecutive healing stages. At infectious inflammatory stage, nHJ-based self-oxygenated photodynamic and photothermal effects synergize with Ag+ to combat multidrug-resistant biofilm-forming bacteria. Subsequently, Ag nanozymes with superoxide dismutase/catalase-like activities continuously scavenge reactive oxygen species while generating oxygen, facilitating macrophage M1-to-M2 repolarization and ensuing inflammatory-to-proliferative phase transition. Accumulated ammonia enhances cell proliferation, migration and angiogenesis. The dressing demonstrates exceptional biocompatibility and bioactivity in accelerating Staphylococcus aureus-infected full-thickness cutaneous wound healing in a diabetic rat model, as validated by hemostatic, broad-spectrum antibacterial, antioxidative and immunomodulatory abilities, enhanced oxygenation and cell proliferation, and extensive collagen deposition, vascularization and re-epithelialization. RNA-seq results further reveal the activation of multiple pro-healing signaling axes. Consequently, this platform offers a powerful dynamic strategy of realizing robust antibacterial activity and active temporal niche modulation to guide the healing of infected diabetic wounds.

The co-evolution of multidrug resistance amongst oral pathogens and sub-par treatment outcomes associated with traditional OSCC therapy calls for alternative strategies, which not only differ in terms of the underlying mechanism but should also be biocompatible. One such strategy entails nanoparticle synthesis utilizing plant extracts as both reducing agents and ligands; secondary metabolic compounds endow the produced nanomaterials with unique biological activity. The aim of the present review is a comprehensive analysis of the preparation, characterization, and dual antibacterial/antitumorigenic activities of AgNPs, CuNPs, and FeNPs produced from aqueous extracts of Azadirachta indica and Syzygium cumini. The nucleation, growth kinetics, size distribution, and particle charge are all governed by the polyphenols content of aqueous plant extract; in particular, Syzygium cumini nanoparticles display monodispersity and low particle sizes (&lt;20 nm) in comparison to larger Azadirachta indica nanoparticles that show enhanced stability due to the abundant presence of terpenoids. Amongst oral biofilm-forming bacteria, AgNPs have shown the greatest breadth of antimicrobial action at the minimum concentration range of 5-25 μg/mL; AgNPs showed greater than 90% biofilm inhibition whereas CuNPs showed antifungal efficacy against Candida albicans. FeNPs, though inherently less cytotoxic, offer a magnetically responsive platform for targeted drug delivery and localized hyperthermia. In OSCC cell lines, biogenic nanoparticles induced dose-dependent apoptosis through mitochondrial membrane depolarization, upregulation of the Bax/Bcl-2 ratio, cytochrome c release, and caspase-3 activation, with selectivity indices consistently superior to chemically synthesized counterparts — attributed to the modulation of oxidative thresholds by surface-adsorbed phytochemicals. Taken together, these phytometallic nanocomplexes represent a mechanistically integrated dual-action platform with potential translational relevance to precision oral therapeutics.

Gas therapy shows significant clinical promise for antimicrobial applications by effectively modulating bacterial activity and suppressing biofilm formation. Nevertheless, the limited gas release efficiency continues to pose a major challenge that compromises its therapeutic effectiveness. Here, we designed and constructed a multilayer nanocomposite (HBAC) using hollow polydopamine (HPDA) as the primary carrier for the nitric oxide (NO) donor N,N'-di-sec-butyl-N,N'-di-nitroso-p-phenylenediamine (BNN6). By grafting gold nanocages (Au NCs) onto its surface, the photothermal conversion efficiency (PCE, η) was significantly enhanced, optimizing the real-time NO release. Furthermore, leveraging the hollow structure and nanoenzyme activity of Au NCs, we encapsulated the antimicrobial agent curcumin (Cur), enabling HBAC to simultaneously activate three synergistic antibacterial modes: gene-like inhibition, photothermal therapy (PTT), and photodynamic therapy (PDT) under near-infrared laser irradiation. This multifunctional platform exhibits exceptional efficacy in suppressing the growth and biofilm formation of diverse Gram-positive and Gram-negative bacteria, including S. epider, E. coli, B. subt, and E. aero, with a bactericidal efficiency exceeding 95%. Our approach offers a promising strategy to enhance gas sterilization efficiency and accelerate the clinical translation of multimodal antimicrobial therapy.

ABSTRACT The increasing rates of multidrug-resistant (MDR) bacterial infections with the complication of biofilm formation can pose a significant threat to global public health. The present work has involved rational design, synthesis and overall antimicrobial assessment of new pyrazole-isoxazole hybrid scaffolds which target non-adherent as well as adherent bacterial groups. compounds, N'-[(1-(4-chlorophenyl)-1H-pyrazol-4-yl)methylidene]-3-phenylisoxazole-5-carbohydrazide (H1) and N'-[(1-(4-methoxyphenyl)-1H-pyrazol-4-yl)methylidene]-3-phenylisoxazole-5-carbohydrazide (H2), were synthesized via acid-catalyzed condensation of substituted pyrazole-4-carbaldehydes with 3-phenylisoxazole-5-carbohydrazide, achieving yields of 82-85%. The structural elucidation was done using the 1H-NMR, FT-IR, ESI-MS. In vitro antimicrobial evaluation against clinically relevant drug-resistant strains of methicillin-resistant Staphylococcus aureus (MRSA ATCC-43300) and multidrug-resistant Pseudomonas aeruginosa (MDR-PA ATCC-27853) showed promising activity: MIC values were 6.25 to 25.0-μg/ml. It is worth highlighting that H2 with 4-methoxyphenyl substituent was more potent (MIC=6.25 μg/ml against MRSA) compared to the standard ciprofloxacin (MIC=16 μg/ml). Assays of crystal violet biofilm inhibition showed concentration-dependent effectiveness of antibiofilm; H2 exhibited 76.4% biofilm reduction at a half of MIC with MRSA. Time-kill kinetics proved the bactericidal effect, and &gt; 4Log10 reduction of CFU at 2X MIC. These results set pyrazole-isoxazole hybrids as privileged scaffolds on the formation of subsequent-generation antimicrobials that can interfere with growth of bacteria and resistance by biofilm. Keywords: hybrids of pyrazole-isoxazole, antimicrobial action, biofilm formation, multidrug resistance, Methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, hydrazone.