Search Results (1,307)

Staphylococcus aureus (S. aureus) bovine mastitis is a significant public health issue. Despite enormous efforts, important gaps remain regarding host–microenvironmental factors. How intramammary reduced oxygen modulates S. aureus transcription in bovine mammary epithelial cells (MECs) remains unclear. We examined oxygen-associated transcriptional changes in a bovine-mammary adapted S. aureus clone following internalization into MECs and identified functional category enrichments under Normal-O₂ and Reduced-O₂ exposures. Bovine MAC-T monolayers were infected with a dominant bovine mastitis isolate under Normal-O₂ or Reduced-O₂ conditions. Triplicate infection experiments were performed for each oxygen condition. Each condition included matched non-reacted bacterial controls maintained under the same gas condition but without MAC-T exposure serving as the reference condition for expression calling. RNA was extracted and profiled using a high-throughput qRT-PCR platform covering genome-wide loci. Expression calls were mapped to curated BioQT roles and interpreted descriptively. Results indicated 211 loci were upregulated and 99 were downregulated under Normal-O₂ conditions, versus 53 upregulated and 35 downregulated under Reduced-O₂ conditions, relative to their non-reacted controls. Under Normal-O₂ conditions, regulated loci covered multiple functional roles, including cellular processes, transport/binding proteins, regulatory functions, and energy metabolism with downregulated loci enriched in transport/binding and cell-envelope categories. Under Reduced-O₂ conditions, upregulated loci were abundant in cellular process annotations dominated by pathogenesis/toxin-related functions, whereas downregulated loci were enriched in nucleotide biosynthetic and DNA/cell division categories. Thus, this reveals oxygen-associated shifts in the transcriptional response of intramammary S. aureus in MAC-T cells. Normal-O₂ conditions were associated with broader category representation, whereas Reduced-O₂ conditions yielded a narrower distribution enriched for selected toxin/pathogenesis- and iron/cation-associated annotations. These oxygen-linked transcriptional-shifts highlight candidate pathways for the intramammary adaptation of S. aureus, potential diagnostic markers, anti-virulence strategies, and targeted therapeutics. Full article

Foodborne diseases present a serious public health challenge, causing roughly 600 million illnesses and 420,000 deaths annually. A significant portion of this impact is felt in Asia, where traditional fermented and dry-salted seafood, such as katsuobushi, budu, and peda, are dietary staples. These products rely on diverse microbial communities that determine their final safety, flavor, texture, and shelf life. Historically, research has centered on lactic acid bacteria (LAB), yet the functional contributions of non-LAB halotolerant species, including genera like Tetragenococcus, Staphylococcus, and Bacillus, are functionally important in these high-salinity niches. This review evaluates the transition from basic taxonomic surveys to mechanistic multi-omics approaches, integrating genomics, transcriptomics, proteomics, and metabolomics to decode microbial functionality under selective environmental pressures. We discuss how genomic mining using platforms such as BAGEL4 and antiSMASH can uncover biosynthetic gene clusters and antimicrobial peptides, while CARD supports antimicrobial resistance monitoring. Transcriptomic analysis reveals microbial responses to osmotic stress, low water activity, and pH fluctuations, whereas proteomic profiling links gene expression to active enzymes, stress proteins, and functional biomarkers. Metabolomics captures the chemical outcomes of fermentation, including amino acids, volatile organic compounds, spoilage markers, and biogenic amines. By merging these high-dimensional datasets with artificial intelligence, researchers can move toward predictive modeling that distinguishes biological causation from simple correlation. This shift offers a strategy to improve the safety, consistency, and resilience of traditional high-salinity fermented seafood systems. Full article

Microalgae hold great potential towards pharmaceutical and nutraceutical sectors due to their substantial content of highly functional bioactive compounds. To assess their potential as a sustainable source of valuable products, 10 cyanobacterial and 10 eukaryotic microalgal strains belonging to different taxonomic groups (Chlorophyta, Cyanophyta, Euglenophyta, Heterokontophyta and Rhodophyta) were screened for their biochemical profile, antioxidant and antimicrobial activity against Staphylococcus aureus. Total phenol content and antioxidant activity were positively correlated (r = 0.69, p < 0.01), with the highest values observed in Euglena cantabrica, Haematococcus pluvialis, and Chrysoreinhardia giraudii. HPLC-PAD pigment analysis revealed species-specific profiles, with β,β-carotene as major carotenoid in most cyanobacteria, whereas neoxanthin, violaxanthin and lutein were predominantly present in Chlorophyta, and fucoxanthin was the main carotenoid in C. giraudii, Entomoneis sp. and Isochrysis galbana. Protein content ranged from 9.2 ± 0.4% to 57.6 ± 0.5% with the highest levels in the cyanobacteria Microcystis aeruginosa, Nostoc sp., Cylindrospermum stagnale, Anabaena minutissima, and Arthrospira platensis. Multivariate analysis differentiated cyanobacteria and eukaryotes based on their fatty acid profiles. Organic extracts from 15 species showed inhibitory effects against S. aureus with MIC50 < 1024 µg/mL. The eukaryotes Entomoneis sp., C. giraudii, I. galbana, Picochlorum sp. and the cyanobacteria C. stagnale and Nodularia sp. exhibited the strongest inhibitory effects on bacterial growth. In conclusion, E. cantabrica and C. giraudii stood out for their high antioxidant activity and significant antimicrobial effects, respectively, highlighting their potential as valuable sources of bioactive compounds. Full article

Background/Objectives: Four novel thymol–benzimidazolium–chalcone hybrids were designed based on a molecular hybridization strategy that integrates bioactive scaffolds known for their antimicrobial and antioxidant properties. This approach aims to enhance biological activity through synergistic effects and multi-target interactions, as supported by previous studies on phenolic and benzimidazole derivatives. The inclusion of both antioxidant and antibacterial evaluations was motivated by the well-established role of oxidative stress in bacterial pathogenicity and resistance mechanisms. Methods: Their antibacterial potential was initially screened using the disk diffusion method and subsequently evaluated by determining MIC and MBC values against eight clinical Staphylococcus aureus isolates. Results: Among the tested compounds, compound 3a emerged as the most potent derivative, exhibiting MIC values ranging from 0.25 to 1 µg/mL. Morphological analysis confirmed significant disruption of bacterial cell integrity, and further investigation demonstrated strong antibiofilm activity accompanied by downregulation of key biofilm- and resistance-associated genes (icaA, dltB, and mepA). Molecular docking studies were performed against selected target proteins, including 1MWT, 3VSL, 3ZG5 (sortase A), and 2ZCS, which are associated with bacterial cell wall biosynthesis, DNA replication, virulence, and metabolic pathways. Compound 3a exhibited the highest binding affinity, with a docking score of −11.953 kcal/mol against 2ZCS. Conclusions: Overall, these findings highlight the potential of thymol-based benzimidazolium–chalcone hybrids as promising multifunctional agents with combined antibacterial, antibiofilm, and antioxidant properties. Full article

In the current research, graphene and cellulose nanocrystals (CNCs) loaded with silver nanoparticles were synthesized using the hydrothermal method with different mass ratios (G:CNC:CS). The composite GC2 (1:0.2:0.2) (MIC = 6.1 µg·mL⁻¹) and GC3 (1:0.3:0.3) (MIC = 1.8 µg·mL⁻¹) exhibited the maximum antibacterial activity against Staphylococcus aureus subsp. aureus ATCC BAA-977 and Pseudomonas aeruginosa, respectively. The antibacterial performance underscores the complex interplay between the compositional attributes of GC2 and GC3, and the unique susceptibility profiles of different bacterial strains. The antibacterial mechanism was proposed to understand the antibacterial activity process. Ag⁺ cations and reactive oxygen species (ROS) formed with the composite materials are responsible for disrupting interactions with the bacterial cell wall via transmembrane proteins. Eriochrome Black T exhibited the highest photocatalytic degradation efficiency (~90% under UV), followed by Congo Red, which also showed substantial removal across all irradiation conditions. In contrast, Bisphenol A and tetracycline displayed comparatively lower degradation efficiencies, particularly under UV light. Overall, the degradation trend for all pollutants followed the order: UV > solar > visible irradiation. Full article

Background: Atopic dermatitis (AD) is a chronic inflammatory disease characterized by profound microbial dysbiosis, Staphylococcus aureus (S. aureus) colonization, and a compromised epidermal barrier. Current therapies often face safety and compliance limitations, necessitating proactive, steroid-sparing ecological strategies focused on barrier restoration. Methods: This pharmacological review evaluates a synergistic framework combining Lactobacillus and Saccharomyces postbiotic lysates with Perilla frutescens-derived effector vesicles. The analysis focuses on their molecular impact on skin homeostasis and structural protein synthesis. Results: In vitro evaluations indicate that Lactobacillus enhances innate immunity, while Saccharomyces-derived metabolites support the microbial ecosystem. Preliminary data demonstrate a significant impact on structural integrity, showing an 87.9% increase in elastin secretion and a 61.4% increase in Type I collagen synthesis. Furthermore, Perilla frutescens-derived vesicles modulate the JAK–STAT pathway, demonstrating a potential reduction of Interleukin-6 (IL-6) by 40% and a downregulation of CYP1A1 expression by up to 49% in cell models, thereby suggesting a capacity to mitigate oxidative stress and pruritus. Conclusions: By integrating these components into a “Triple-Action” framework, focusing on immunomodulation, structural restoration, and precision signaling, this review provides a comprehensive roadmap for promising dermo-cosmetic interventions in atopic skin management. Full article

Thymol has been granted “Generally Recognized as Safe” status by the US Food and Drug Administration. However, its application as a natural preservative is constrained by limitations such as poor water solubility and high volatility. In this study, a dual-protein complex was prepared using mung bean protein and whey protein isolate to stabilize thymol-loaded oil-in-water (O/W) Pickering emulsions. The results demonstrated that the dual-protein system was driven by hydrogen bonding, electrostatic attraction, and hydrophobic interactions. Compared to single-protein systems, the dual-protein Pickering emulsions possessed smaller droplet sizes, lower polydispersity indices, and higher surface charges and surface hydrophobicity. Additionally, the dual protein enhanced emulsifying activity, thermal stability, and 30-day storage stability. Notably, the complex formed a continuous three-dimensional porous network structure at the mung bean protein (MBP) to whey protein isolate (WPI) ratio of 50%:50%. Benefiting from this structure and high surface hydrophobicity, the 50%:50% formulation achieved the highest thymol encapsulation efficiency. In terms of functional properties, this optimized emulsion demonstrated notable antibacterial activity and antioxidant activity; it demonstrated antibacterial activity against Shewanella putrefaciens and Staphylococcus aureus. Furthermore, the IC₅₀ value for the 50%:50% formulation was 192.25 ± 1.93 μg/mL (DPPH) and 161.74 ± 0.71 μg/mL (ABTS). In summary, the 50%:50% formulation enhanced the emulsifying activity, encapsulation efficiency, and bioactivity of the emulsion. This system provides an effective strategy for the stabilization and encapsulation of hydrophobic active compounds in emulsions. Full article

Polluted mangroves are ecologically sensitive habitats that provide ecosystem services. In a selected polluted forest of Simaisma, viable aerobic, halophilic, and heterotrophic hydrocarbon-degrading bacterial strains were isolated from both rhizosphere and non-rhizosphere regions. The chemical composition of sediment showed a clear distinction between the rhizosphere and non-rhizosphere sites, as well as coastal and non-coastal sediments, as per Principal Component Analysis (PCA) clustering. Anthracene, an indicator of oil pollution, was present along with vanadium, another marker of oil pollution. Through selective enrichment cultures, a total of 25 hydrocarbon-degrading bacterial strains were isolated, including Lysinibacillus xylanilyticus, Bacillus cereus, Lysinibacillus sphaericus, Pseudomonas stutzeri, Acinetobacter calcoaceticus, and Staphylococcus warneri. To link the adaptation of bacteria to sediment chemistry, nine B. cereus strains were investigated using their MALDI-TOF MS protein profiles combined with their dendrogram. The relationship between protein profiles of B. cereus strains with their biosurfactant production capabilities was explained by a tanglogram. The tanglegram suggests that biosurfactant production is an important functional trait in B. cereus, but it is not consistently reflected in the overall protein profile. This suggests that bacterial adaptation in the polluted mangrove sediments may involve changes at multiple cellular levels, including metabolic activity and variation in protein expression profiles. These findings confirm the involvement of mangrove-associated bacteria in the sustainability of mangrove forests by promoting bioremediation of oil pollution, thereby protecting coastal ecosystems and their environmental and socio-economic aspects. Full article

Antimicrobial resistance (AMR) has become a major concern in the treatment of bacterial infections, and bacteriophage therapy has emerged as a promising alternative to antibiotics. Bacteriophages are highly specific to their bacterial hosts; hence, isolating phages indigenous to a specific region offers a significant advantage against various pathogen strains. We have isolated a cocktail of bacteriophages against pathogenic E. coli from sewage water at a primary healthcare centre. Characterisation of the isolated phages demonstrated their stability across a broad pH and temperature range, strong lytic activity, and effective biofilm degradation, with no cross-reactivity with Staphylococcus aureus (S. aureus). Genomic analysis and phylogenetic studies indicated that the largest phage (by genome size) in the cocktail belongs to the genus Vequintavirus (myoviruses, rV5-like phages), and its genome sequence has been deposited in NCBI (Accession ID: PX741096). The phage genome was linear, with headful (PAC) packaging, encoded lysis proteins, and lacked antibiotic-resistant or major lysogeny-associated genes, collectively suggesting a lytic lifestyle. These findings emphasize the therapeutic potential of rV5-like phages and underscore the critical need to establish phage banks in India to improve disease management. Full article

Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa rank among the most challenging pathogens due to increasing prevalence of multidrug-resistant (MDR) strains. These pathogens pose major risks to public health and food safety, earning their inclusion on the World Health Organization (WHO) priority list of MDR bacteria. While available conventional antibiotics are becoming less effective, natural products from plant extracts offer promising alternative and synergetic effects that can restore efficacy and lower required doses. Their antimicrobial activity is attributed to phytochemicals such as phenolic compounds and terpenoids acting via membrane disruption, efflux pump inhibition, biofilm interference, and cell protein disruption. Furthermore, phytochemicals in essential oils, such as carvacrol, thymol, and cinnamaldehyde, also exhibit antimicrobial and antioxidant activities. Their broad antimicrobial effects extend shelf life and enhance food safety, making them effective natural alternatives to synthetic preservatives. Moreover, advances in extraction and characterization techniques, including green solvents, spectrometry and hyphenated chromatographic methods, have improved recovery, identification and quantification. In addition, artificial intelligence (AI) emerges as a transformative tool to accelerate discovery, optimize compound screening, and predict synergistic interactions. Notwithstanding these advances, challenges persist in standardization, bioavailability, and clinical translation. Further studies are needed to isolate active compounds, elucidate mechanisms of action, validate combined use with conventional antibiotics and overcome formulation, delivery, sensory and regulatory hurdles. This review examines current knowledge of opportunities and limitations of plant-based antimicrobials against MDR pathogens supported by advances in extraction, characterization, and AI. Full article

Meat serves as a prime medium for the growth of foodborne pathogens due to its rich protein content and high water activity, contributing significantly to the global burden of foodborne illnesses. This review synthesizes current advances in meat-borne bacterial pathogen detection with particular emphasis on emerging artificial intelligence (AI)-enabled applications. Major pathogens of concern, including Salmonella, Listeria monocytogenes, Escherichia coli, Campylobacter, Clostridium, and Staphylococcus aureus, are examined in relation to their relevance across the meat supply chain. Recent progress in biosensors (clustered regularly interspaced short palindromic repeats), CRISPR-based assays, isothermal amplification, and metagenomics is evaluated alongside the growing role of AI in automating signal interpretation, enhancing image-based diagnostics, and supporting early contamination prediction. AI-based systems have proved 96.4–104% recovery and 100% bacterial capture ability. Embedding AI methods in a wet lab demands technical and logical modeling, as well as learning and calibration decorum. Nonetheless, AI readiness and full-scale application for meat-borne pathogens surveillance are on the way. Furthermore, additional focus is aligned on meat-borne bacterial pathogen genomic databases, i.e., (NCBI Pathogen Detection, EnteroBase, VFDB, ComBase, and GenBank), which serve as critical training resources for AI models for outbreak tracking, virulence profiling, and antimicrobial resistance (AMR) prediction. By integrating molecular methods, genomic surveillance, and AI-driven analytics, this review presents a framework for strengthening meat safety systems. This will improve early detection capabilities and support data-driven public health interventions in the future. Full article

Lactic acid bacteria (LAB) are valuable natural bio-preservatives due to their ability to produce antimicrobial compounds such as organic acids, hydrogen peroxide, and bacteriocins. This study aimed to isolate and characterize LAB from Moroccan camel meat and evaluate their antimicrobial potential against major foodborne pathogens. From 2304 isolates obtained from fresh, fermented, and dried camel meat, 115 exhibited antimicrobial activity against Listeria monocytogenes, Salmonella enterica Enteritidis, and Staphylococcus aureus. Seven isolates demonstrated broad-spectrum activity with inhibition zones ranging from 15 to 30 mm. Physiological and biochemical tests, combined with API 20 Strep identification, revealed that most isolates belonged to Enterococcus faecium. These isolates are promising candidates for natural preservation of camel meat, offering a sustainable alternative to synthetic preservatives. These findings highlight the potential of camel-meat-associated lactic acid bacteria as natural, clean-label bio-preservatives, particularly in arid regions where camel meat serves as a vital protein source and limited cold-chain infrastructure increases the risk of spoilage. Full article

Mastitis is a common disease in dairy cows, mainly caused by Staphylococcus aureus and Escherichia coli. Berberine (BBR) has antibacterial and anti-inflammatory potential, but its application is limited due to poor oral absorption and difficulty in reaching mammary tissue. To address this, this study developed a BBR-loaded composite ethosome hydrogel (BBR-CEH) to achieve targeted mammary delivery through local transdermal administration. The experimental results showed that BBR-CEH has good chemical stability and biosafety. Subsequently, a mouse mastitis model was established by intraductal injection of 50 µL of bacterial mixture (E. coli:S. aureus = 1:1, each at 1 × 10⁷ CFU/mL). The results showed that after BBR-CEH treatment, the mRNA expression of TNF-α (tumor necrosis factor-alpha), IL-6 (interleukin-6), and IL-1β (interleukin-1 beta) was significantly decreased, the mRNA expression of ZO-1 (zonula occludens-1), Occludin, and Claudin-4 was significantly increased, and Bax/Bcl-2 (Bcl-2-associated X protein/B-cell lymphoma 2) was significantly reduced (p < 0.01), indicating alleviation of mastitis by reducing inflammation, improving tight junctions, and inhibiting apoptosis. Finally, network pharmacology and in vivo experiments confirmed that its mechanism involves the NF-κB (nuclear factor kappa-B) and PI3K/Akt (phosphoinositide 3-kinase/protein kinase B) pathways. Thus, topical BBR-CEH may represent a promising new strategy for mastitis treatment. Full article

Pterospartum tridentatum (L.) Willk. (carqueja) is widely used in traditional medicine and culinary practices in the Iberian Peninsula; however, most studies have focused on its flowers, while its stems remain largely unexplored, despite representing a significant proportion of the plant biomass. This study aimed to evaluate the potential of P. tridentatum stems as a source of bioactive compounds using different extraction methodologies. Aqueous, hydroethanolic, ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) were applied, and the resulting extracts were characterized in terms of their extraction yield, protein and carbohydrate content, phenolic composition, antioxidant capacity, antimicrobial activity, and cytotoxicity in HaCaT and Caco-2 cell lines. Phenolic profiling by LC-ESI-QqTOF-HRMS tentatively identified 37 compounds, mainly corresponding to flavonoid and isoflavonoid glycosides, with genistein derivatives representing the dominant constituents across all extracts. Although extraction yields differed among methods, phenolic profiles were broadly similar. UAE and PLE extracts showed slightly higher antioxidant activity, while antimicrobial activity was limited, with only moderate inhibition observed against Staphylococcus epidermidis and Malassezia furfur. Additionally, cytotoxicity assays indicated low toxicity. Overall, the results demonstrate that P. tridentatum stems represent a promising yet underutilized biomass source of phenolic compounds with antioxidant potential and low cytotoxicity under the tested in vitro conditions. Full article

Background/Objectives: The Korean Global Antimicrobial Resistance Surveillance System monitors bloodstream Staphylococcus aureus infections by combining antimicrobial susceptibility testing (AST) with conventional polymerase chain reaction (PCR). Considering the clinical significance of methicillin-resistant S. aureus (MRSA), we performed an in-depth analysis of isolates showing genotypic–phenotypic discrepancies. Methods: Isolates were collected from designated collection centers in the Republic of Korea between 2017 and 2024. The 30 μg cefoxitin disk diffusion method was used to define the phenotypes. PCR targeting mecA and the staphylococcal cassette chromosome mec (SCCmec) was used to identify genotypes through gel electrophoresis. Long-read whole-genome sequencing (WGS) was performed using the Revio system (Pacific Biosciences) for isolates exhibiting discrepancies between phenotypes and genotypes. Results: In total, 5808 isolates were screened, and seven cases of genotypic–phenotypic discrepancies were identified, including one infant and six elderly patients with chromosomal SCCmec type IV. Although WGS confirmed intact PCR primer-binding sites, structural alterations were observed: three isolates had normal-length mecA and mecR1, two had partial deletions in mecA, and two featured either mecA or mecR1 split into two proteins. Notably, although the six isolates with intact mecR1 genes matched the nucleotide length of SCCmec type IV, their sequences exhibited high homology with SCCmec type II. Conclusions: Despite the presence of mecA, the non-standard configuration of regulatory genes within the SCCmec elements suppressed actual resistance expression. Because conventional PCR focusing on partial gene segments could overlook such phenotypic traits, the meticulous observation and implementation of WGS are crucial for the accurate characterization of genotypic–phenotypic discrepancies. Full article