Search Results (34,542)

Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot, one of the most destructive bacterial diseases on crucifer crops, resulting in yield losses of up to 90%. The aim of this study was to identify novel endophytic bacteria from cabbages with potential biocontrol agents against Xcc. A total of sixty-five isolates were evaluated for plant growth-promoting characters and antagonistic activity, from which ten were selected for in planta assays and subsequently validated under field conditions. Pseudomonas synxantha BR25/2 consistently demonstrated the highest efficacy, reducing disease severity by 81.12% in in planta trials and 33.5% in field trials, thereby comparing to copper-based control measures. Additionally, Pseudomonas synxantha BR25/2 significantly enhanced yield parameters, including a 31.8% increase in head weight under field conditions. Whole-genome sequencing identified biosynthetic gene clusters, including siderophores, phenazines, and non-ribosomal peptide synthetases, notably a coronatine-like NRPS and a fengycin-like betalactone, suggesting an extensive antimicrobial potential of metabolites. This represents the first report of P. synxantha exhibiting control over Xcc. For commercial application, large-scale fermentation and encapsulation techniques are recommended to overcome shelf-life challenges, providing a sustainable microbial solution for crucifer production. Full article

The preweaning period is a critical phase for dairy calves, during which gastrointestinal disorders, particularly diarrhea, remain a major cause of morbidity and antimicrobial use. Astaxanthin, a xanthophyll carotenoid with antioxidant and anti-inflammatory properties, has shown potential to support intestinal health in several animal species, but information in preweaning dairy calves is limited. The objective of this study was to evaluate the effects of astaxanthin supplementation administered through milk replacer on growth performance, clinical health, metabolic profile, and fecal microbiota in preweaning Holstein calves. Twenty-four female Holstein calves (body weight, mean ± SD: 49.51 ± 12.14 kg) were randomly assigned to a control group (CTR; n = 12) or an astaxanthin-supplemented group (TRT; n = 12). Treated calves received 40 mg/d of astaxanthin from week 0 to 4 and 80 mg/d from week 4 to 8. Body weight, feed intake, rectal temperature, and fecal consistency score, fecal color score and clinical scores were recorded throughout the trial. Blood samples were collected in weeks 0 and 8 for metabolic profiling, and fecal samples were collected in weeks 0, 4, and 8 to assess fecal consistency and bacterial populations. Astaxanthin supplementation did not affect body weight, average daily gain, or overall feed intake. However, treated calves exhibited a lower frequency of abnormal fecal consistency scores, indicating reduced diarrhea incidence compared with control calves. Fecal microbiological analysis revealed lower coliform counts in astaxanthin-supplemented calves in weeks 4 and 8, whereas total bacterial counts were greater in week 8. Most blood metabolites were primarily influenced by age-related physiological changes; however, circulating calcium concentrations were greater in treated calves. These results suggest that astaxanthin may represent a promising nutritional strategy to support gastrointestinal health during early life, although larger studies are needed to confirm these findings. Full article

Background: The antibiotic ibezapolstat and the live biotherapeutic product live-JSLM are promising future approaches for treating Clostridioides difficile infection. Ibezapostat is a highly specific antibiotic for Clostridioides difficile, with minimal impact on the intestinal flora. Live-JSLM is designed to restore healthy intestinal microbiota, thus preventing recurrence of Clostridioides difficile infection. In this narrative review, we reviewed available data on ibezapostat and live-JSLM, considering that they are prototypes of two distinct, unique mechanisms of action against Clostridioides difficile. Methods: Data sources: PubMed and SCOPUS databases were searched from 1 January 2012 to 15 November 2025. Original articles reporting data on ibezapolstat and live-JSLM were included. Results: 31 studies were included. When compared to conventional anti-Clostridioides difficile antibiotics, ibezapolstat had a similar level of effectiveness and minimal impact on the gut microbiota. The available data confirm live-JSLM safety and efficacy in restoring the gut microbiota following the conclusion of the standard anti-Clostridioides difficile antibiotic regimen. Conclusions: The results on ibezapolstat efficacy are promising, but require confirmation in larger patient populations through double-blind, randomised phase III trials. In the near future, an integrated approach may enhance the management of Clostridioides difficile infection: starting with highly specific antibiotics, i.e., ibezapolstat, followed by microbiome-based therapies such as live-JSLM. Full article

Alzheimer’s disease (AD) is characterized by progressive cognitive decline and the accumulation of amyloid-β (Aβ) plaques and tau neurofibrillary tangles. Beyond genetic and proteostatic mechanisms, infection- and dysbiosis-based models of AD have gained renewed attention, including the antimicrobial protection hypothesis, in which Aβ may participate in innate immune defense. Here, we reanalyzed ribosomal depleted (Ribo-Zero) RNA-seq data from dorsolateral prefrontal cortex (DLPFC) samples from the Mount Sinai Brain Bank cohort (GSE53697) to screen for non-human transcripts. Reads underwent quality control and adapter trimming, taxonomic classification with Kraken2, abundance re-estimation with Bracken, and differential abundance testing with edgeR. Across 17 samples (9 advanced AD and 8 controls), we detected low-biomass microbial signals, with Acinetobacter radioresistens showing enrichment in the AD group (FDR = 0.018). Several additional taxa showed suggestive group differences but did not remain significant after multiple testing correction, including Lactobacillus iners (FDR = 0.051). We also performed an exploratory in silico analysis of an A. radioresistens biofilm-associated protein homolog, identifying predicted amyloidogenic motifs and surface-exposed regions that may be relevant to cross-seeding hypotheses, although no mechanistic inference can be drawn without experimental validation. Given the technical challenges of inferring microbial signals from post-mortem brain RNA-seq data, including contamination risk, low microbial biomass, and overwhelming host background, these findings should be interpreted as hypothesis-generating and warrant orthogonal validation in larger, microbiome-aware cohorts. Full article

This study was carried out to investigate the antimicrobial performance and color stability of silver (Ag)-modified polyurethane and waterborne coating systems applied to Oriental beech (Fagus orientalis L.) wood after the specimens were subjected to UV aging for 24 h. Antimicrobial activity and color stability were evaluated before and after aging against Escherichia coli (E. coli, ATCC 25922), Staphylococcus aureus (S. aureus, NCTC 13552), and Candida albicans (C. albicans) in accordance with the JIS Z 2801 standard. Color changes were determined using CIELab parameters (ΔL*, Δa*, Δb*, and ΔE*) in accordance with the TS EN ISO 16474-3 standard. Prior to UV exposure, the highest antibacterial activity against E. coli occurred in Ag-modified waterborne varnish coatings, whereas the highest antifungal activity against C. albicans occurred in Ag-modified polyurethane paint systems. After UV aging, antimicrobial performance varied depending on the coating type. Particularly, Ag-modified waterborne varnish coatings retained significant antibacterial activity against E. coli and S. aureus and exhibited the highest antifungal performance against C. albicans. Color analysis revealed that UV exposure also caused significant changes in all coating systems. The most pronounced variations were observed for the lightness difference (ΔL*), red–green color difference (Δa*), and yellow–blue color difference (Δb*) parameters, while the lowest total color difference (ΔE*) values were observed for Ag-modified polyurethane and Ag-modified waterborne varnish coatings. Overall, Ag-modified waterborne varnish systems demonstrated superior performance in both antimicrobial activity and color stability after UV aging. Full article

Background/Objectives: Multidrug-resistant (MDR) Escherichia coli has increasingly been recognized as a pathogen capable of causing severe systemic infections in various animal species. However, reports describing respiratory and septicemic infections caused by MDR E. coli in guinea pigs remain scarce. The objective of this report was to describe the clinical, pathological, and microbiological findings associated with a fatal infection in a domestic guinea pig. Case Study: A 10-month-old female guinea pig (Cavia porcellus), kept as a companion animal in a household environment, presented with acute respiratory distress, lethargy, and anorexia, progressing rapidly to death within approximately 36 h of onset. Post-mortem examination revealed severe pulmonary congestion, diffuse inflammatory lesions in the trachea, and generalized vascular congestion in multiple organs. Bacteriological cultures obtained from lung and bone marrow samples yielded pure growth of Escherichia coli. Identification was confirmed using MALDI-TOF mass spectrometry. Antimicrobial susceptibility testing demonstrated resistance to several antibiotic classes, including β-lactams, fluoroquinolones, tetracyclines, sulfonamides, and phenicols, while susceptibility was retained only to aminoglycosides. Molecular analysis revealed the presence of virulence genes involved in adhesion and iron acquisition, supporting the pathogenic potential of the isolate. Conclusions: This report highlights the ability of MDR E. coli to cause severe respiratory and systemic infections in guinea pigs. The findings underline the importance of early diagnosis, appropriate antimicrobial stewardship, and improved husbandry conditions in preventing such infections. From a One Health perspective, the circulation of resistant strains in companion animals may represent a potential risk for both environmental and human health. Full article

Background/Objectives: The WHO has identified carbapenem-resistant Acinetobacter baumannii (CRAb) and carbapenem-producing Enterobacterales (CPE) as the “critical priority” group of multidrug-resistant (MDR) organisms for which new therapeutic strategies are urgently needed. Here, we evaluated the in vitro synergistic activity of eugenol, cinnamaldehyde, and carvacrol in combination with β-lactams, gentamicin, or colistin against MDR Gram-negative bacteria (GNB). Methods: We selected seven MDR-GNB clinical isolates including CRAb, ESBL-producing and CPE clinical isolates displaying different antimicrobial susceptibility profiles. The genomes of clinical isolates were characterized by whole-genome sequencing and synergy testing was performed with checkerboard assay. Results: Our results demonstrate that eugenol, cinnamaldehyde, and carvacrol in combination with colistin exhibited synergistic activity (FICI < 0.5) against MDR-GNB clinical isolates ranging from 37.5 to 50%, while the effect was almost indifferent in combination with different β-lactam molecules or gentamicin against 87.5–100% of MDR-GNB strains. The synergistic interaction of eugenol, cinnamaldehyde, and carvacrol with colistin induced a statistically significant reduction (p < 0.05) in the MIC values compared with the molecules tested alone. Conclusions: Our data demonstrate that this synergistic interaction was not affected by different antimicrobial resistance genes and/or different antimicrobial susceptibility profiles. In conclusion, our results suggest that eugenol, cinnamaldehyde, and carvacrol in combination with colistin represent a potential strategy for the treatment of MDR-GNB pathogens and limit their diffusion. Full article

This study investigated the microbiological composition and antimicrobial resistance (AMR) profiles of artisanal goat and sheep milk cheeses produced in Poland. Ten raw milk cheeses (five each from goat and sheep milk) were analyzed using a combined approach involving culture-dependent enumeration, 16S rRNA gene sequencing, and antibiotic susceptibility testing. Microbial counts revealed substantial variability among the samples, with lactic acid bacteria (LAB) dominating the microbiota. Taxonomic analysis confirmed the predominance of Lactococcus, Streptococcus, and lactobacilli, although marked intra-group heterogeneity was observed. Multivariate analyses indicated that sample-specific factors had a greater influence on microbiome composition than milk origin. Among 170 isolates, 28.7% were classified as multidrug-resistant (MDR), being most prevalent in Enterobacterales (100%) and Enterococcus spp. (73%), whereas LAB exhibited low resistance levels (16.2%). Resistance was most frequently associated with aminoglycosides and β-lactams. The resistance results were interpreted according to CLSI guidelines. These findings demonstrate that artisanal cheeses harbor complex, dynamic microbial ecosystems that may serve as reservoirs of antimicrobial resistance. The results highlight that environmental and technological factors, rather than milk source alone, are key drivers of both microbiome structure and resistance distribution, underscoring the need for targeted AMR monitoring in traditional dairy products. Full article

Antimicrobial peptides (AMPs) have re-emerged as promising anti-infective agents, particularly against multidrug-resistant bacteria; however, their therapeutic development remains constrained by proteolytic degradation, host cell toxicity, and rapid systemic clearance. Rather than focusing solely on sequence discovery, recent efforts have shifted toward structural and supramolecular modification strategies aimed at improving stability, selectivity, and pharmacological performance. This review critically analyzes intramolecular modifications—including phosphorylation, glycosylation, acetylation, methylation, and backbone cyclization—that modulate peptide conformation and resistance to enzymatic degradation. In parallel, extramolecular approaches such as PEGylation, lipidation, and conjugation to antibiotics, siderophores, or antibodies are examined in the context of enhanced targeting and prolonged bioavailability. Particular emphasis is placed on localized delivery systems, including hydrogels, polymeric films, and nanofibrous scaffolds, which enable spatially controlled administration and mitigate systemic exposure. By integrating evidence from ex vivo and in vivo infection models, this work delineates the translational potential and remaining bottlenecks of chemically engineered AMP platforms for skin and soft tissue infections. Full article

Background: Salmonella enterica subsp. enterica serovar Gallinarum biovar Pullorum (Salmonella Pullorum) is a specific avian pathogen responsible for Pullorum disease, causing substantial economic losses to the global poultry industry. With the rising restrictions on antibiotic use, probiotics have emerged as promising therapeutic alternatives. The Bacillus subtilis group, including B. amyloliquefaciens and B. subtilis, is a collection of closely related species that has been widely used as a probiotic due to its broad-spectrum antimicrobial activity and other benefits. However, how the probiotics-derived antibacterial phenotype contributes to infection control is still unclear. Methods: In this study, we used two different antibacterial phenotype strains, B. amyloliquefaciens and B. subtilis, to treat S. Pullorum infections. The spores of two strains (10⁷ CFUs) were supplemented daily for 21 days. Results: The reduction in body weight gains and the severity of S. Pullorum-induced symptoms were ameliorated. Compared to B. subtilis, B. amyloliquefaciens exhibited a stronger host protection effect, manifested in a greater reduction in the bacterial load of S. Pullorum in organs throughout the infection. Furthermore, both strains enhanced cecal microbiota diversity, suppressed infection-associated taxa, and promoted beneficial genera. Conclusions: Our findings demonstrate that probiotic Bacillus can alleviate S. Pullorum infection and improve growth performance in poultry, especially the antimicrobial phenotype contributing to pathogen clearance. This work provides crucial insights for developing effective, probiotic-based strategies against Pullorum disease. Full article

Background/Objectives: Antimicrobial resistance (AMR) is a critical global public health challenge driven by inappropriate and excessive antimicrobial use (AMU) across human, animal, and environmental sectors. Method: This narrative review synthesizes recent evidence on antimicrobial utilization and resistance patterns. A structured search of PubMed, Scopus, and Web of Science was conducted for studies published between 2015 and 2025. Eligible sources included surveillance reports, registry-based analyses, and clinical studies. Data were qualitatively analyzed to identify key trends and regional variations. Result: Marked geographical variation in AMR was observed. Carbapenem resistance in Escherichia coli remains low globally (2–3%) but is higher in Southeast Asia (17–18%) and India (~40%). Klebsiella pneumoniae shows consistently high resistance (>40% globally; ~54% in India), while Pseudomonas aeruginosa exhibits stable resistance levels (35–45%). Resistance prevalence increases from primary to tertiary care settings, reflecting greater antimicrobial exposure. Vulnerable populations—including pediatric, elderly, pregnant, and immunocompromised patients—face higher risks of antimicrobial exposure and adverse outcomes, including nephrotoxicity, hepatotoxicity, and microbiome disruption. WHO AWaRe data indicate a global shift toward increased use of Watch-category antibiotics. Stewardship interventions, such as audit and feedback, prescribing restrictions, rapid diagnostics, and decision support systems, effectively reduce inappropriate AMU. Conclusions: Integrated, data-driven antimicrobial stewardship and robust surveillance systems are essential to mitigate the global burden of AMR. Full article

Kefir grains are a valuable source of exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) with potential applications in fermented dairy products. In this study, LAB isolated from kefir grains originating from five regions were screened for EPS production and probiotic-related properties. Three strains, Lactiplantibacillus plantarum XZ61, Lactobacillus kefiranofaciens EG10, and Lentilactobacillus kefiri EG12, were selected based on high EPS yield, antimicrobial activity, antioxidant capacity, and tolerance to acidic and bile salt conditions. After optimization, the highest EPS yield (539.57 μg/mL) was obtained from strain EG10.The purified EPS consisted of two molecular weight fractions (≈1.4 and 23~25 kDa) and was rich in mannose (33.38~61.58%). Among the three EPS, EG10-EPS exhibited superior emulsifying and flocculating properties comparable to commercial stabilizers, as well as notable ABTS^•+ and hydroxyl radical scavenging activities. Furthermore, co-fermentation of L. kefiranofaciens EG10 with conventional yogurt starter cultures significantly improved exopolysaccharide content, water-holding capacity, texture, and antioxidant activity of fermented milk, particularly in cow milk. These results demonstrate the potential of kefir-derived EPS-producing LAB as natural functional cultures for fermented dairy applications. Full article

The skin serves as the first line barrier of innate immunity, protecting the body from external influences and maintaining its homeostasis. Exogenous and endogenous stress factors alter the structure and functional properties of the skin. The search for compounds capable of counteracting these processes has allowed the identification of peptides as promising ingredients of products for medicinal and cosmetic applications. This review comprehensively examines the mechanisms of action and dermatological applications of two distinct classes of natural products—endogenous human peptides and those derived from marine organisms. Human peptides exhibit numerous biological functions, including antimicrobial and immunomodulatory ones, as well as promoting antioxidant protection and wound healing. Microbiome-associated peptides are an underestimated but powerful regulator of skin aging through immunomodulation, inflammation control, barrier function maintenance, and selection of the proper microbial community. Peptides from marine organisms exhibit significant structural diversity and a broad spectrum of biological activity, including regenerative effects and effects on antibiotic-resistant microorganisms. This review summarizes current data obtained from in vitro, ex vivo, and clinical studies demonstrating a broad potential of peptides for maintaining skin health. Both peptide classes represent powerful, targeted strategies for innovative dermatological interventions aimed at promoting skin rejuvenation, protection, and overall homeostasis. Full article

Background/Objectives: Staphylococcus aureus (S. aureus) intramammary infection remains a major global dairy problem due to its contagious nature, its ability to persist and colonize teat/skin and mucosal niches, and the often-limited bacteriological cure achieved with antimicrobial therapy. Beyond udder health, it is relevant to public health because it can enter raw milk chains and serve as a reservoir for antimicrobial resistance determinants that may circulate between dairy animals and humans. Methods: We assessed S. aureus’ ecology in raw ewe milk from 75 sheep farms in Epirus (Greece) by sampling clinically healthy controls (group A) and clinical mastitis cases pre-treatment (group B), followed by resampling at the first post-withdrawal milking after penicillin/streptomycin treatment (group C1—therapeutic protocol 1), oxytetracycline treatment (group C2—therapeutic protocol 2), or enrofloxacin treatment (group C3—therapeutic protocol 3). Results: S. aureus detection was high and comparable across groups (A 23.0%, B 22.0–30.0%, C 20.0–22.0%), and paired analyses showed no significant pre–post shifts in detection/burden within therapeutic protocols (all p > 0.05). Nevertheless, persistence remained evident. The chromosomal gene mecA was detected in S. aureus strains in all groups, ranging from 13.6% in controls to 54.5% post-withdrawal in group C1, and was also present in the pre-treatment group. In paired sampling animals, mecA was mostly stable, with rare emergence or loss. Across antibiotic classes, within-animal resistance transitions were generally uncommon and non-significant (p > 0.05); β-lactam resistance was fully stable (p = 1.00). Descriptively, resistance to protein synthesis inhibitors tended to decline after therapy in protocol 1 and protocol 3, while protocol 3 showed post-treatment gains in fluoroquinolone resistance. By contrast, virulence-associated phenotype traits shifted after therapy: enterotoxigenicity increased post-withdrawal (especially in the C3 group), Staphylococcal Enterotoxin A (SEA) and Staphylococcal Enterotoxin B (SEB) appeared only post-therapy, Staphylococcal Enterotoxin D (SED) increased significantly in paired isolates (p = 0.002), and strong biofilm adherence increased (in C3, p = 1.5 × 10⁻⁵). Conclusions: The detection of S. aureus after therapy suggests that one possibility is that antimicrobial exposure may select for, or otherwise reshape, the residual intramammary population, rather than reliably eliminating it—an outcome that remains clinically relevant for udder health. Moreover, the persistence of mecA/methicillin-resistant Staphylococcus aureus (MRSA)-compatible profiles indicates that milk released to the food chain after withdrawal compliance may still harbor S. aureus with enhanced preservation capacity and significant food safety relevance. Full article