Search Results (34,587)

Background: Respiratory tract infections remain among the most common indications for antibiotic therapy and represent a major driver of antimicrobial resistance. The ability of respiratory pathogens to form biofilms further contributes to treatment failure and recurrence. This study aimed to evaluate the antibiotic adjuvant potential of selected essential oil components against clinically relevant respiratory bacteria and to determine whether planktonic synergistic interactions translate into early-stage antibiofilm efficacy. Thymol, eugenol, trans-cinnamaldehyde, and terpinen-4-ol were tested against Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis, methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa. Methods: Minimum inhibitory concentrations were determined by broth microdilution. Synergistic interactions with clinically relevant antibiotics were assessed using the checkerboard method and fractional inhibitory concentration index (FICI) analysis. Selected combinations were further evaluated in a 6 h crystal violet-based early-stage biofilm model. Gram-positive strains generally exhibited higher susceptibility to the tested components than Gram-negative bacteria. Results: Synergistic interactions (FICI ≤ 0.5) were most frequently observed between β-lactam antibiotics and phenolic components, particularly thymol and trans-cinnamaldehyde. Strong synergy was detected for vancomycin-eugenol against MRSA and for amoxicillin/clavulanic acid–cinnamaldehyde against M. catarrhalis. Importantly, synergistic combinations translated into significantly enhanced inhibition of early biofilm formation, increasing inhibition rates by 15–40% compared to antibiotic monotherapy (p < 0.05). Selected essential oil components enhanced the antibacterial activity of clinically relevant antibiotics and effectively potentiated early-stage biofilm inhibition. Conclusions: These findings support further investigation of phytochemical-antibiotic combinations as potential adjunct strategies in respiratory infection management. Full article

The high prevalence of biofilm-associated multidrug-resistant (MDR) Escherichia coli infections in older adults calls for novel control strategies. This study compared fecal E. coli carriage, antimicrobial resistance, and biofilm formation among community-dwelling older adults with different self-reported immune statuses (lower vs. normal), and evaluated the antibiofilm activity of five Lactobacillus cell-free supernatants (CFSs). Fecal samples from 20 older adults were analyzed. E. coli was enumerated, and isolates were characterized for antimicrobial susceptibility and biofilm formation. Five Lactobacillus strains were screened for antibiofilm activity using crystal violet assay, with further evaluation of extracellular polymeric substance (EPS) production and biofilm morphology. After removing the redundant isolates, 70 isolates were reported, with significantly higher counts in the lower-immunity group (7.89 vs. 6.04 log MPN/g). The lower-immunity group had significantly higher antimicrobial resistance (97.3% vs. 60.6%), and higher MDR prevalence (91.7% vs. 24.2%). Biofilm formation was observed in 62.9% of isolates, with significantly higher prevalence among MDR isolates and in the lower-immunity group. L. paracasei L475 CFS showed the strongest antibiofilm activity against a representative MDR isolate (L5-1), with inhibition and eradication rates of 82.9% and 75.0%, respectively. Mechanistically, L475 CFS reduced extracellular polymeric substance components, with a 92.3% reduction in proteins and 41.3% in polysaccharides. Microscopy confirmed disrupted biofilm architecture, membrane damage, and cell lysis. In conclusion, these preliminary findings indicate a potential association between self-reported immune function and E. coli resistance/biofilm formation in older adults. L. paracasei L475 CFS demonstrates promising in vitro antibiofilm activity against an MDR E. coli isolate from this population, supporting its potential as a postbiotic candidate. Full article

Plant fungal diseases, such as apple tree canker caused by Valsa mali, have caused severe losses in agricultural production. Traditional chemical fungicides induce drug resistance in pathogens and cause environmental pollution. Therefore, it is of substantial importance to screen efficient and environmentally friendly bacterial strains as potential biocontrol agents. The tea rhizosphere harbors abundant microbial resources, and previous research has identified microorganisms with antifungal activity existing in this environment. Therefore, in this study, we isolated antagonistic bacteria with broad-spectrum biocontrol potential from tea rhizosphere soil. In this study, a strain with strong antagonistic activity against V. mali was isolated from tea rhizosphere soil. Based on morphological characteristics, 16S rRNA gene sequencing, and whole-genome analysis, the isolated strain was identified as Bacillus velezensis and designated as LW-66. This strain demonstrated broad-spectrum antifungal activity against various plant pathogenic fungi, including Valsa mali, Fusarium graminearum, Bipolaris sorokinianum, Alternaria solani, and Exserohilum turcicum. The active extract of B. velezensis maintained strong stability across a wide range of temperatures (25–90 °C) and pH values (2–8), with stability decreasing only when the temperature reached 100 °C or pH ≥ 10. In a preventive assay using detached apple branches inoculated with V. mali, the control efficacy of LW-66 against apple tree canker reached more than 90%. Additionally, in a therapeutic assay using V. mali-infected potted apple seedlings, the LW-66 bone-glue bacterial agent achieved a survival rate of up to 90%. Whole-genome analysis revealed that the genome of LW-66 contains 13 predicted secondary metabolite biosynthetic gene clusters, seven of which showed high homology (≥92% similarity) with known antimicrobial gene clusters, including surfactin, bacillaene, macrolactin H, fengycin, difficidin, bacillibactin, and bacilysin. These gene clusters may be connected to the broad-spectrum antifungal activity of B. velezensis, as well as its ability to disrupt hyphal morphology. The volatile organic compounds produced by LW-66 inhibited V. mali growth by 91.70%. Collectively, these findings demonstrate that B. velezensis LW-66 has a wide antimicrobial range and strong antagonistic effects against multiple plant pathogenic fungi. Therefore, B. velezensis shows promise as a biocontrol agent for managing fungal diseases in plants, providing a basis for developing LW-66-derived biocontrol products aimed at controlling diseases such as apple tree canker. Full article

Background/Objectives: Carbon dots (CDs) are promising antimicrobial nanomaterials owing to their biocompatibility, environmental friendliness, and tunable surface chemistry. This study aimed to synthesize nitrogen-doped CDs (AS-CDs) and develop a light-responsive antibacterial system through conjugation with chlorin e6 (Ce6). Methods: AS-CDs were synthesized by a microwave-assisted method using L-ascorbic acid and spermidine, followed by conjugation with Ce6. The materials were characterized by transmission electron microscopy, zeta potential analysis, and spectroscopic methods, and their antibacterial activity was evaluated against Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA) under both dark and visible-light conditions. Cytotoxicity was assessed using HaCaT cells. Results: The AS-CDs exhibited a uniform nanoscale morphology with an average diameter of 6.3 nm and a positive surface charge of +15.6 mV, together with intrinsic broad-spectrum antibacterial activity. Ce6 conjugation further enhanced antibacterial efficacy under light irradiation, with the CDs-Ce6 conjugate achieving complete eradication of S. aureus and MRSA and marked inhibition of E. coli at 2.5 μg/mL. Cytotoxicity studies demonstrated low toxicity in HaCaT cells within the effective antibacterial concentration range. Conclusions: These findings highlight the potential of microwave-synthesized, photosensitizer-conjugated CDs as next-generation antimicrobial agents. This platform offers a cost-effective, sustainable, eco-friendly, and efficient platform for combating bacterial infections, with broader potential in pharmaceutical and biomedical applications. Full article

Camel-associated antimicrobial resistance (AMR) is an underrecognized component of the One Health landscape, particularly in the Gulf Cooperation Council (GCC) and North Africa. Available evidence demonstrates the presence of clinically significant resistance mechanisms in camel populations, including extended-spectrum beta-lactamases, carbapenemases, colistin resistance genes, and multidrug-resistant clones. Molecular similarities between camel and human isolates suggest potential cross-species transmission and highlight camels as possible reservoirs within interconnected human–animal–environment systems. Despite documented resistance patterns, camel production systems remain largely excluded from national AMR surveillance and stewardship frameworks. This gap reflects limited camel-specific data on antimicrobial usage and structural challenges related to pastoral mobility, cross-border trade, and emerging commercial intensification. Strengthening diagnostic capacity, implementing tailored antimicrobial stewardship strategies, and integrating camels into national AMR action plans are essential to mitigate potential public health risks. Proactive inclusion of camel systems within regional AMR governance frameworks is necessary to prevent further amplification of resistance. Full article

Background/Objectives: The Saker Falcon (Falco cherrug) is an endangered raptor species of ecological and conservation relevance. Despite its status, data regarding its microbiota and the prevalence of antimicrobial resistance (AMR) remain scarce, especially in Eastern Europe. This single-facility study aims to investigate the phenotypic and genotypic AMR profiles of Gram-negative bacteria isolated from captive Saker Falcons in Western Romania. Methods: Freshly voided fecal droppings were collected non-invasively from 40 clinically healthy Saker Falcons. Bacterial identification was performed using selective media and the VITEK^® 2 system. Antimicrobial susceptibility testing (AST) was conducted on a representative subset of 12 isolates. Selected resistance-associated genes were screened by conventional PCR. Results: Escherichia coli was the most prevalent 60% (n = 24/40), followed by Hafnia alvei 10% (n = 4/40) and Pseudomonas spp. 10% (n = 4/40). AST revealed phenotypic resistance among Enterobacteriaceae primarily to ampicillin 20% (n = 2/10), tetracycline 20% (n = 2/10), fluoroquinolones and sulfonamides 10% (n = 1/10), while susceptibility to imipenem 90% (n = 9/10) and gentamicin 90% (n = 9/10) remained high. The targeted resistance-associated genes were detected in selected phenotypically resistant isolates. PCR screening detected blaZ and ampC in 62.5% (n = 5/8) of tested isolates, blaOXA-61 in 37.5% (n = 3/8), blaOXA-51 in 25% (n = 2/8), tetK in 37.5% (n = 3/8), and gyrA in 12.5% (n = 1/8). The isolate used as the negative control, pansusceptible in AST, was confirmed negative for all targeted genes. Conclusions: This single-facility study provides baseline data on AMR traits in Gram-negative bacteria associated with Saker Falcons in Western Romania. Given the limited scale and isolate-based design of the study, the findings should be interpreted cautiously, but they support further investigation of wildlife-associated AMR within a One Health context. Full article

Background: Antimicrobial resistance (AMR) is a global health threat arising from inappropriate antibiotic use. Data on the prescription of antibiotics in emergency departments (EDs), critical care points for infection management, are limited. Objective: This study aimed to assess systemic antibiotic use in an Indonesian ED. Methods: This retrospective observational study was conducted in the Cilacap Teaching Hospital ED in 2022. Data, including patient demographics and systemic antibiotic prescription details (World Health Organization Anatomical Therapeutic Chemical (WHO ATC): J01) were extracted from electronic medical records. Antibiotic use was analyzed according to age groups (children [0–14 years], adults [15–64 years], and the elderly [≥65 years]), administration route, and the World Health Organization Access, Watch, and Reserve classification. Results: Among all ED visits during the study period, 52.1% (14,396/27,640) received systemic antibiotics, and adults comprised 68.5% (9861/14,396) of antibiotic-exposed cases. Cephalosporins were the most frequently prescribed antibiotics in all age groups (42.4–50.9%). Penicillins were more frequently prescribed in children (29.9%) than in adults (10.0%) and the elderly (6.6%), whereas fluoroquinolones were more commonly prescribed in the elderly (21.1%) than in adults (16.2%) and children (3.8%). Watch-class antibiotics, comprising 63.9% of all prescriptions, were commonly prescribed in the elderly (71.9%). Oral route was the predominant form (65.8%), particularly in children (76.5%). The most frequently prescribed antibiotics differed across age groups, with amoxicillin followed by cefixime in children, and cefixime followed by ceftriaxone in both adults and the elderly. Conclusions: This study showed high antibiotic exposure and identified age-related differences in antibiotic prescribing, and patterns that warrant further evaluation within antimicrobial stewardship frameworks, to optimize antibiotic use and mitigate AMR. Full article

Municipal solid waste disposed of in open dumpsites and unlined landfills contaminates groundwater, soils, and air across urban areas of low- and middle-income countries. Nevertheless, impacts across all three environmental media have not been systematically assessed together. We conducted a PRISMA 2020-compliant systematic review of 286 peer-reviewed studies from PubMed, Dimensions, and OpenAlex, applying structured eligibility screening and quality appraisal using an adapted JBI checklist. Heavy metals—lead, cadmium, chromium, and zinc—were the most frequently detected contaminants in leachate and groundwater, commonly exceeding WHO drinking water guidelines by one to three orders of magnitude. Soil contamination by potentially toxic elements was documented at virtually all open dumpsites studied, persisting for decades after site closure. Particulate matter at South Asian MSW sites reached up to 41 times the WHO 2021 annual guideline. Microplastics acting as heavy metal carriers and dumpsite leachate as a source of antimicrobial resistance genes were identified as emerging risks outside standard monitoring frameworks. Non-carcinogenic hazard indices exceeded acceptable thresholds in the majority of health risk studies reviewed. Engineered containment was the strongest predictor of contamination severity across all sites. Phytoremediation, constructed wetlands, and biofiltration showed promise as mitigation approaches. Critical evidence gaps remain for Central Asia, harmonized reporting standards, and longitudinal monitoring data. Full article

Probiotics are known to improve gut microbiota balance, enhance food digestion, and support overall health. Among these, Bacillus species are particularly promising due to their safety, spore-forming ability, environmental resilience, and diverse enzymatic activities. However, most Bacillus probiotics used in industry are of terrestrial origin, leaving marine-derived strains largely unexplored. Utilising the untapped potential of marine microbial biomass, this study presents a multi-stage methodology for identifying and evaluating marine-derived Bacillus strains with probiotic potential. A structured screening pipeline was applied to 67 microbial isolates from the Great Barrier Reef sponges. Initial selection focused on essential probiotic characteristics, including growth, stability, safety, and survival under gastrointestinal conditions. Strains meeting these criteria were then assessed for desirable properties, including digestive enzyme production and pathogen inhibition. Using this workflow, three marine-derived Bacillus strains were identified as potential probiotics, one of which demonstrated strong antimicrobial activity against Salmonella enterica at 5 and 10 mg/mL (p < 0.01). These findings demonstrate the capability of marine-associated Bacillus as novel bioproducts with functional antimicrobial properties. Full article

Silver nanoparticles (AgNPs) are widely recognized for their potent antibacterial properties and diverse biomedical applications. While conventional synthesis methods typically rely on chemical-reducing agents that may pose risks to human health and the environment, this study proposes an eco-friendly green synthesis approach utilizing porcine skin extracts. The extracts were prepared through thermal treatment and filtration to serve as a biological reducing agent. Successful synthesis was validated using dynamic light scattering, Fourier transform infrared (FTIR) spectroscopy, UV–Vis spectroscopy, and scanning electron microscopy (SEM). Furthermore, the antimicrobial efficacy of the synthesized AgNPs was evaluated against multidrug-resistant microorganisms, demonstrating significant growth inhibition across various antibiotic-resistant strains. These findings suggest that porcine skin—a readily available bioresource—is a promising precursor for the sustainable production of AgNPs with broad-spectrum antimicrobial potential. Full article

Astrocaryum murumuru Mart., an Amazonian oilseed widely used for cosmetic oil production, generates large amounts of residual biomass that remains underexplored. In this study, ultrasound-assisted extraction (UAE) with ethanol as a green solvent was optimized using a Central Composite Rotational Design (CCRD) with 2 levels (2³) and 3 independent variables. The optimal condition (60 % ethanol, solid–liquid ratio 2.5 % m/v, 26 min) was determined using response surface methodology (RSM), and yielded 9.92 mg GAE/g of total phenolic content (TPC), with an experimental error of 5.34 % compared to the theoretical model prediction. Under this condition, total flavonoids and tannins were also quantified, reaching 0.38 ± 0.01 mg QE/g and 4.03 ± 0.10 mg TA/g, respectively. LC-MS analysis revealed a complex phenolic profile within the extract, confirming the efficiency of UAE in recovering bioactive molecules. Biological assays revealed significant functional properties. Antioxidant activity, evaluated by ABTS and DPPH methods, indicated that the extracts were effective radical scavengers. Antimicrobial assays showed only growth-selective inhibition against Staphylococcus aureus at concentrations of 2.5–20 mg/mL, while no significant activity was observed against Escherichia coli and Pseudomonas spp. These findings highlight the potential of A. murumuru biomass residues as a sustainable source of bioactive compounds with antioxidant activity and a growth inhibitor of S. aureus, reinforcing their possible application in the development of natural additives for food, while contributing to the sustainable bioeconomy of the Amazon. Full article

Macroalgal species are widely distributed throughout the world’s oceans and are well recognised for their biotechnological, ecological, and pharmacological potentials, containing a wide range of diverse bioactive compounds. In many coastal habitats worldwide, excessive accumulations of algal biomass (including rapidly growing blooms and drift accumulations resulting from dislodgement from benthic habitats) are commonplace and can pose environmental and economic challenges. In this study, we report occurrences of algal blooms and drift accumulations during 2024 and 2025 involving three major macroalgal clades, Chlorophyta, Phaeophyceae, and Rhodophyta, from two distinct marine regions: the North Atlantic Ocean and the South Pacific Ocean. Species identified included Grateloupia turuturu, Polyides rotundus, Ascophyllum nodosum, Ulva spp., Sargassum spp. and Fucus spp., among others. The indicated species are known for their diverse pharmacological properties, including antimicrobial, antioxidant, and anti-inflammatory effects. Specialised bioinformatic tools were employed to assess the potential of identified macroalgae as a source of antimicrobial peptides (AMPs). For selected macroalgal species, in silico screening of publicly available databases was performed to identify previously reported and characterised AMPs associated with these species. This in silico approach presents a promising strategy for discovering novel antimicrobial agents with potential activity, especially against drug-resistant bacteria. Finally, applying proteomics methodologies for in silico evaluation of the selected algal species advances modern technologies for the sustainable use of natural resources. Full article

In recent years, there have been important regulatory and management changes in livestock farming in Italy and other European countries. The goal of these changes has been to decrease the use of antimicrobials (antimicrobial stewardship). The objective of this observational study was to explore the potential relationship between the decrease in the use of antimicrobials and the rise in the culling of dairy cattle on 210 farms in the Lodi province. Records of antimicrobials used in dairy herds (measured as the daily defined dose animal for Italy—DDDAit) and culling rates were retrieved from the Italian Ministry of Health official databases. These were statistically analyzed to assess the presence of an association between changes in the DDDAit and changes in the culling rates in 2023 and 2024. The results indicated that the DDDAit exhibited minimal fluctuations over the two-year period (3.61% vs. 2.45%). However, there was a notable shift observed in the culling rates, particularly among smaller herds (24.51 vs. 39.27%). The statistical analysis showed a significant correlation between herd size and antimicrobial treatment, with a higher frequency in larger herds. The results of this study indicate that reducing antimicrobial treatments alone may not necessarily result in better animal welfare or herd sustainability, particularly when it is associated with an increase in the culling rate. It also suggests that antimicrobial treatment rates and culling rates derived from a mandatory recording system provide a simple means of verifying the level of herd health management and of assessing the antimicrobial stewardship approach efficacy. Full article

The emergence of antimicrobial resistance and the increasing incidence of cancer have highlighted the urgent need to develop new drugs; therefore, the discovery of new bioactive molecules is an important goal for future research. In this study, freshwater fungi isolated from submerged Phragmites australis from Egypt were screened for antimicrobial and cytotoxic activities. Using ITS1 and ITS4 primers, eight frequently occurring Sordariomycetes taxa were identified and were then selected for further evaluation of bioactivity. Ethyl acetate crude extracts (A–H) were evaluated for antimicrobial activity using the agar disk-diffusion method. Extracts A and E, derived from Chaetomium globosum SCUF0000404 (PX596738) and Chaetomium madrasense SCUF0000401 (PX596735), respectively, showed broad-spectrum activity at 100 mg/mL against bacterial pathogens, including Staphylococcus aureus ATCC 29213 (15.33 and 18.00 mm), Streptococcus pyogenes ATCC 19615 (11.00 mm), Escherichia coli ATCC 35218 (10.33 and 10.67 mm), Klebsiella pneumoniae ATCC 700603 (14.00 and 16.67 mm), and Pseudomonas aeruginosa ATCC 27853 (13.33 and 16.33 mm), and show antifungal activity against Candida albicans ATCC 14053 (20.33 mm), Candida krusei ATCC 6258 (15.67 and 15.33 mm), Trichosporon asahii AMS 187 (17.00 and 17.67 mm), Exserohilum rostratum AMS 1077 (34.00 and 33.67 mm), and Trichophyton indotineae AMS 180 (38.33 and 34.00 mm). Selective cytotoxic effects on the breast cancer cell line MDA-MB-231 were observed by extracts A and E at IC₅₀ = 309 and 277 μg/mL, while non-selective cytotoxic effects on the normal HUVEC cell line were found with IC₅₀ = 919 and 796 μg/mL, respectively. Characterization of the most effective extracts A and E by high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) shows that they have a wide range of secondary metabolites, including cytochalasans, azaphilone alkaloids, steroids, terpenoids, flavonoids, and phenols. These findings underscore the chemical diversity and therapeutic potential of freshwater fungi from Egypt. Full article

Basil essential oil (BEO) has emerged as a promising natural alternative to antibiotic growth promoters in poultry production. BEO has shown antimicrobial, antifungal, anticoccidial, antioxidant, and insecticidal properties. BEO exhibits broad antimicrobial activity against Gram-positive and Gram-negative pathogens, and modulates gut microbiota by decreasing Escherichia coli and Staphylococcus spp. Anticoccidial effects include reduced oocyst shedding, improved intestinal morphology, and downregulation of pro-inflammatory cytokines. Antifungal activity reduces fungal load and inhibits Aspergillus spp., with implications for control spoilage and aflatoxin risk. BEO at a concentration of 40 ppm was effective in preventing E. tenella invasion, showing an average reduction in invasion by 36% in primary chicken epithelial cells. Antioxidant benefits include enhanced intestinal and systemic antioxidant status. Advanced nanoformulation technologies, particularly nano-encapsulation, have substantially overcome several limitations for BEO application in poultry. Further research is still required to assess the efficacy of nano-encapsulated BEO for enhancing overall poultry industry productivity. This review synthesizes current evidence on BEO integration in the poultry production sections, from nutrition and disease control to product preservation and farm hygiene, and evaluates technological solutions that address formulation barriers. Moreover, it discusses critical research gaps and proposes future directions for enhancing BEO applications in sustainable poultry production systems. Full article