Search Results (1,171)

Foodborne diseases remain a major global public health concern. According to the World Health Organization (WHO), contaminated food causes nearly 500,000 deaths annually. Consequently, the development of novel strategies to control foodborne pathogens and prevent microorganism-induced plant diseases remains an important research priority, attracting considerable scientific attention worldwide. This study describes the design and synthesis of novel dihydropyrazolines containing an ethylpiperazine moiety as potential antimicrobial agents. The antibacterial activity of the newly synthesized heterocyclic compounds, along with their corresponding chalcone precursors, was evaluated against Gram-positive and Gram-negative foodborne pathogens and phytopathogenic bacteria. The assessment was performed using a two-step protocol comprising an initial qualitative screening of selected bacterial species, followed by a quantitative evaluation of the inhibitory effects of individual compounds and their combinations. Among the tested compounds, pyrazolines 4a and 4b and chalcone 3b exhibited notable strain-dependent antibacterial activity, particularly against phytopathogenic strains of Pseudomonas syringae, while compound 4a demonstrated the highest efficacy against the Gram-negative foodborne pathogens Escherichia coli, Salmonella enterica and Listeria monocytogenes. Thus, the potential of the N-ethylpiperazine moiety as a key structural feature contributing to the antimicrobial activity of the studied compounds is revealed. Full article

Satureja nepeta essential oil (EO) is gaining prominence for its multifaceted pharmacological and biotechnological potential. This study aimed to characterize its volatile profile and evaluate its functional capacity as an antioxidant, antibacterial, and antiproliferative agent. Gas Chromatography Mass Spectrometry (GC–MS) profiling was conducted to identify the volatile constituents of the EO. Antioxidant activity was assessed using DPPH, ABTS, TAC, and FRAP assays. Antibacterial activity was evaluated against Gram-positive and Gram-negative pathogens using disk diffusion and MIC determination. In silico molecular docking against bacterial DNA gyrase B was performed to explore potential mechanisms of action. Antiproliferative activity was assessed on the P3X63Ag8.653 myeloma cell line. Chemical profiling identified nine major constituents, dominated by pulegone (68.63%), menthol (6.64%), and cis-pulegol (2.04%). The EO demonstrated significant free radical-scavenging activity, particularly in the TAC assay (EC₅₀ = 3.747 ± 0.577 µg/mL). Antimicrobial evaluations revealed robust inhibitory effects, with Pseudomonas aeruginosa and Salmonella enterica exhibiting the highest susceptibility. In silico modeling corroborated these findings, identifying menthol as the lead ligand (ΔG = −6.09 kcal/mol), suggesting a synergistic mechanism of action. Notably, the EO displayed potent antiproliferative activity (LC₅₀ = 14.060 ± 1.364 µg/mL), falling well within the high-cytotoxicity threshold. Collectively, these findings underscore the pharmacological significance of S. nepeta EO as a potent reservoir of bioactive monoterpenes with antioxidant, antimicrobial, and anticancer properties, meriting further in vivo validation and mechanistic exploration toward its development as a therapeutic or nutraceutical candidate. Full article

This study investigated the inhibitory effect of nanoemulsions (NEs) derived from various essential oils (EOs) and seed oils (SOs) against pathogenic bacteria isolated from rainbow trout (Oncorhynchus mykiss). The EOs of eucalyptus, mandarin, and basil were extracted by hydrodistillation, while the SOs of avocado and pumpkin were extracted by supercritical fluids. GC–MS analysis determined the chemical composition, revealing that limonene (70.88%), eucalyptol (57.85%), and camphor (24.61%) were the main components of the EOs. The SOs were rich in palmitic acid (avocado) and linoleic acids (pumpkin) and contained phytosterols such as β-sitosterol and stigmasterol. Avocado seed oil had the highest total phenolic content and antioxidant activity. Eight stable NEs, prepared from individual and mixed oils, were tested against Salmonella enterica subsp. salamae, Escherichia coli, Klebsiella variicola, Bacillus oceanisediminis, and Bacillus thuringiensis. Most NEs were effective against E. coli and B. oceanisediminis, with an additive effect for SOs mixtures and a minimum inhibitory concentration of 0.53 μL/mL (E. coli), 0.53 μL/mL (B. oceanisediminis), and 2.13 μL/mL (B. thuringiensis). The bacteriostatic and bactericidal activity was 1.62 and 6 h with E. coli and NE Mix AP. These findings suggest that nanoemulsions containing SOs are promising candidates for controlling bacterial contamination in fishery products. Full article

Lactic fermentation modulates polyphenol composition in plant matrices, yet how compositional shifts translate into functional outcomes across extractable (EP) and hydrolyzable (HP) fractions remains unclear. Here, we apply a phenolic–bioactivity connectivity framework to fermented murta (Ugni molinae Turcz) juice, integrating compositional profiling with three functional axes: antimicrobial activity (against Escherichia coli, Salmonella enterica, and Staphylococcus aureus), inhibition of carbohydrate-hydrolyzing enzymes (α-amylase, α-glucosidase) and DPP-IV, and modulation of oxidative stress in Caco-2 cells. Murta juice was fermented with Lactobacillus acidophilus, Lactiplantibacillus plantarum, and a 1:1 coculture under two optimized strategies (GDF and SAW). Principal component analysis separated fermented from unfermented samples (89.7% variance explained) and identified coculture fermentation (MIX-GDF) as the most compositionally distinct treatment. EP fractions drove antimicrobial and α-glucosidase inhibition, whereas HP fractions contributed preferentially to DPP-IV inhibition and intracellular reactive oxygen species (ROS). A bipartite correlation network revealed a dual-functional architecture: specific flavonoid–bioactivity associations governed enzyme inhibition, while diffuse collective interactions shaped antimicrobial responses. These results demonstrate that fermentation-induced phenolic remodeling yields structured, functional outcomes, providing a rational basis for designing fermentation strategies targeting specific bioactivity profiles. Full article

Six lactic acid bacteria isolated from São Jorge PDO cheese were characterised for technological, safety, antimicrobial, and probiotic properties. All isolates fermented a broad range of carbohydrates and lacked lipolytic activity, while SJC115 and SJC119 showed proteolysis. Safety profiling (γ-haemolysis, no DNase or gelatinase activity, and generally favourable antibiotic susceptibility) is promising, but tetracycline resistance warrants caution and genomic confirmation. L. paracasei and L. brevis isolates inhibited a wide range of foodborne pathogens (Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, Bacillus spp.) and spoilage fungi (Penicillium and Aspergillus spp.). Notably, two isolates (SJC117 and SJC120) exhibited antibacterial activity in neutralized cell-free supernatants, indicating putative bacteriocin-like inhibitory substances (BLIS). The isolates survived intestinal conditions above the probiotic threshold, yet only SJC117 and SJC120 tolerated gastric acidity (pH 2.5, 1 h) with >5 log CFU/mL. Despite low hydrophobicity, strains showed good autoaggregation and pathogen coaggregation. All isolates produced exopolysaccharides (EPS) and angiotensin-converting enzyme (ACE) inhibitory peptides, whereas some exhibited moderate conjugated linoleic acid (CLA) production and glutamate decarboxylase (GAD) activity. L. paracasei SJC117 stood out by combining BLIS/antifungal activity, superior gastric tolerance, and an exceptional bioactive profile, making it a promising candidate for biopreservation and functional food applications that warrants further in vivo validation to confirm its efficacy and safety. Full article

Good canine gastrointestinal health depends on the suppression of enteric pathogens and maintenance of epithelial barrier integrity. Limosilactobacillus reuteri ATCC PTA 6127 (Lr6127) is a dog-derived probiotic, but evidence supporting its functional properties remains limited. Here, we evaluated the antimicrobial and epithelial-supportive effects of Lr6127 using a canine epithelial cell model. Cell-free supernatant (CFS) from Lr6127 significantly inhibited the growth of canine-relevant pathogens, including Enterotoxigenic Escherichia coli (52.0 ± 1.3%), Clostridium perfringens (54.0 ± 2.7%), and Salmonella enterica subsp. enterica serovar Typhimurium (48.6 ± 1.2%), compared with the medium control (p < 0.0001). Pathogen inhibition increased in a dose-dependent manner with increasing CFS concentration. Untargeted metabolomic analysis revealed enrichment of multiple antimicrobial-associated metabolites, indicating a multi-component profile consistent with pathogen suppression, with genomic analysis supporting the aromatic amino acid-derived metabolite findings. In addition, viable Lr6127 significantly reduced the epithelial adhesion of all the tested pathogens (p < 0.01). Beyond direct antimicrobial effects, Lr6127 CFS promoted epithelial wound healing at later time points, accompanied by the coordinated modulation of proteins associated with cytoskeletal remodeling and barrier repair. Collectively, these findings support the idea that Lr6127 is associated with antimicrobial and epithelial-related effects, highlighting its potential to contribute to epithelial function under controlled in vitro conditions. Full article

Domestic cats (Felis catus) are ubiquitous companion animals that provide substantial psychological and social benefits to children and adults alike, but they also serve as reservoirs and vectors for a wide range of zoonotic pathogens. Close physical contact between cats and children, frequent use of shared environments such as homes, playgrounds, and sandboxes, and still-developing hygiene behaviours increase opportunities for exposure to protozoa, helminths, bacteria, fungi, and ectoparasite-borne agents. This review synthesizes current evidence on key feline-associated zoonoses of pediatric concern—including Toxoplasma gondii, Toxocara cati, Ancylostoma spp., Dipylidium caninum, Bartonella henselae, Salmonella enterica, Campylobacter jejuni, Pasteurella multocida, Microsporum canis, flea-borne Rickettsia species, and rabies—with emphasis on transmission routes, clinical manifestations, and risk modifiers in children, pregnant women, and immunocompromised individuals. Within a One Health framework, we also summarize global publication trends on feline zoonoses, discuss how urban cat ecology and management (including free-ranging cats in child-frequented environments) may shape pediatric risk, and outline practical prevention strategies centred on hygiene, veterinary care, and targeted education for caregivers and children. Full article

This study evaluates the chemical composition and bioactivities of essential oils extracted from the leaves and twigs of Glycosmis lanceolata growing in a natural forest in Vietnam. gas chromatography–mass spectrometry identified 42 and 43 constituents in the leaf and twig oils, respectively. The main compounds in the leaf oil were (E)-β-caryophyllene (10.2%), β-bisabolene (23.7%), and brevifolin (21.3%), while the twig oil was dominated by β-bisabolene (11.6%) and brevifolin (12.7%). Neither oil exhibited inhibitory effects against two beneficial bacterial strains, Bacillus subtilis and Lactobacillus fermentum. In contrast, both oils showed weak antimicrobial activity against four pathogenic bacteria—Staphylococcus aureus, Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa—and one yeast, Candida albicans, with IC₅₀ values ranging from 2012 ± 118 to 10,593 ± 557 µg/mL. Notably, the twig oil demonstrated pronounced anti-inflammatory activity via inhibition of nitric oxide production (IC₅₀ = 29.7 ± 2.58 µg/mL), whereas the leaf oil showed no detectable activity within the tested concentrations. Similarly, DPPH radical scavenging assays indicated stronger antioxidant activity for the twig oil compared to the leaf oil. These findings provide new insights into the phytochemistry and bioactivities of G. lanceolata essential oils and may support further investigations into their potential applications. Full article

Background: Essential oils (EOs) are promising natural antimicrobials against food-borne pathogens, yet their efficacy depends on complex chemical profiles that vary by species and origin. The evaluation of underexplored aromatic plants from the Peruvian Amazon may reveal novel bioactive agents. Methods: We chemically characterized six EOs from Aloysia citrodora, Arracacia xanthorrhiza (two cultivars), Baccharis genistelloides, Piper acutifolium, and Piper lanceifolium using GC-MS and assessed their antibacterial activity against Escherichia coli (ATCC 25922), Salmonella enterica (ATCC 14028), Enterococcus faecalis (ATCC 29212), and Staphylococcus aureus (ATCC 49476). Results: EOs of Aloysia citrodora and Arracacia xanthorrhiza cv. Yellow exhibited the strongest inhibition, effective against both Gram-positive and Gram-negative bacteria, potentially associated with higher relative abundances of oxygenated monoterpenes and aliphatic aldehydes. Dose–response analysis supported their superior antibacterial potency, with the lowest LD₅₀ values observed for these oils. Oils rich in sesquiterpenes showed lower activity. Conclusions: These findings underscore the importance of EO chemical composition for antibacterial potency and suggest that select Amazonian EOs have potential as natural preservatives for food safety applications. Full article

Date (Phoenix dactylifera L.) pits are a by-product of the date processing industry and are being explored as a source of bioactive compounds within the framework of the circular economy. This study aimed to perform a preliminary safety screening of the in vivo toxicity and mutagenic potential of ethanolic extracts obtained from different date pit varieties. Extracts from Alig (DA), Deglet Nour (DDN), and Kentichi (DK) varieties were administered to Galleria mellonella larvae at different concentrations, and health indices and survival were monitored for 4 days. No significant toxicity was observed at concentrations up to the MIC (6.25 mg/mL), while higher doses (≥2 MIC) had moderate effects on larval viability. The mutagenic potential was evaluated for two extracts (DDN and DK) using the Ames test with Salmonella enterica serovar Typhimurium strains TA98 and TA100, in the absence of metabolic activation. Mutagenic index values were below 2.0 for all conditions tested, with the exception of DDN on TA98, where values consistently exceeded 2.0 without a clear dose–response relationship. Due to the absence of metabolic activation and the limited strain panel, the results should be interpreted as preliminary. Overall, the combined preliminary in vitro and in vivo initial findings suggest that ethanolic extracts of date pits do not exhibit an evident mutagenic or toxic effects at biologically relevant concentrations under the conditions tested, providing a basis for further safety evaluation towards their application in the food industry. Full article

Salmonella enterica comprises numerous serovars with distinct host ranges and disease outcomes. Among them, Salmonella enterica serovar Typhimurium (S. Typhimurium) is a leading cause of gastroenteritis worldwide. Its ability to persist both in the environment and within the host gastrointestinal tract is largely attributed to biofilm formation. In contrast, the human-restricted pathogen Salmonella enterica serovar Typhi (S. Typhi) primarily forms biofilm in the gallbladder during chronic infection. These differences suggest that the two serovars are exposed and respond to distinct environmental cues. Curli fimbriae are key components of the biofilm matrix, contributing to initial surface adhesion and structural stability. In this review, we examine the regulation of curli fimbriae (csg operons) in S. Typhimurium, incorporating recent advances in the field, and compare these mechanisms with new insights concerning regulation in S. Typhi. Comparative analyses highlight significant differences in csg expression and regulatory pathways between the two serovars. All two-component systems known to influence curli expression carry mutations in active protein domains in S. Typhi. This is also true for diguanylate cyclases and phosphodiesterases, with some exhibiting important modifications in S. Typhi, including truncation and insertion. Such polymorphisms could contribute to variation in the curli regulatory pathway and may reflect broader mechanisms of host adaptation in S. Typhi. Understanding this regulatory divergence is essential for elucidating host specificity and the distinct pathogenic strategies of S. Typhi related to biofilm formation. Full article

Atypical Salmonella enterica strains that evade conventional detection pose significant challenges to food safety surveillance. A hydrogen sulfide (H₂S)-negative and serologically untypable S. enterica strain (SF1060) was detected by qPCR from cooked farmed mussels in Galicia, Spain, and characterized using phenotypic and genomic approaches. Despite typical biochemical profiles, SF1060 failed to produce black colonies on Xylose Lysine Deoxycholate (XLD) agar and lacked detectable somatic antigens by conventional serotyping. Hybrid genome assembly using nanopore and illumina sequencing yielded a closed chromosome and five plasmids. In silico analyses identified the strain as S. Senftenberg ST14. Comparative genomics revealed a chromosomal inversion at the rfb operon (encoding enzymes needed to synthesize deoxysugars and O antigens) mediated by IS5-family transposase ISEc68, which truncated the rfbD gene and separated the remaining rfb genes at rfbD, disrupting O-antigen biosynthesis, explaining the inconclusive phenotypic serotyping results. The phs operon responsible for H₂S production lacked premature stop codons, suggesting the H₂S-negative phenotype may result from an alternative mechanism. This study demonstrates how whole-genome sequencing resolves identification of atypical strains that fail culture-based detection and emphasizes the critical need for molecular surveillance methods in seafood safety programs, particularly in regions where atypical S. enterica variants may be endemic. Full article

Antimicrobial resistance (AMR) is one of the most serious threats to global public health, driven in part by extensive antibiotic use in food-producing animals. The poultry industry, a major contributor to the global animal protein supply, has depended on antibiotics for growth promotion and disease control, thereby contributing to the emergence and dissemination of AMR zoonotic bacteria. This review synthesizes current evidence on the potential of phytochemicals (PCs), plant-derived bioactive compounds, as sustainable non-antibiotic alternatives for controlling bacterial foodborne pathogens in poultry. Relevant literature including in vitro and in vivo studies assessing PCs against major poultry-associated zoonotic bacteria, including Salmonella enterica, Campylobacter spp., Clostridium perfringens, Listeria monocytogenes, and pathogenic Escherichia coli, is examined. Evidence indicates that PCs exert antimicrobial and anti-virulence effects through mechanisms like bacterial membrane disruption, inhibition of quorum sensing and virulence gene expression, modulation of gut microbiota, and enhancement of host immune responses. In vivo studies demonstrate reductions in pathogen colonization and improvements in gut health and performance metrics in poultry. Despite these promising findings, challenges remain in bioavailability, dose optimization, standardization, and regulatory approval. Overall, PCs represent a promising component of integrated antimicrobial stewardship strategies in poultry production, with significant implications for mitigating zoonotic AMR transmission. Full article

Salmonella enterica serovar Choleraesuis (S. Choleraesuis) is a swine-adapted zoonotic pathogen for which multidrug resistance has become an increasing concern. An antimicrobial resistance profile and multidrug resistance pattern in S. Choleraesuis isolates from diseased pig in Taiwan have been reported. This study was designed as a secondary molecular and statistical analysis of 272 isolates recovered from diseased pigs in Taiwan whose minimum inhibitory concentration phenotypes had been reported previously. Using this isolate collection, we evaluated phenotype–genotype concordance and coresistance patterns by combining antimicrobial susceptibility data with targeted polymerase chain reaction screening and quinolone resistance-determining region sequencing. Multidrug resistance was detected in 97.8% of isolates. Among the screened acquired determinants, blaTEM was the most prevalent gene (94.5%), followed by floR (55.9%) and mcr-1 (12.9%); mcr-3 was detected in only one isolate. Significant phenotype–genotype concordance was observed for aphA-1 with kanamycin resistance and mcr-1 with colistin resistance. Sequence analysis of 60 enrofloxacin-resistant isolates revealed that high-level resistance was associated with combined gyrA and parC substitutions, with additional gyrB-region polymorphisms observed in isolates showing the highest minimum inhibitory concentrations. These findings demonstrate frequent coresistance patterns and complex resistance mechanisms in this lineage and support continued genomic surveillance and prudent antimicrobial stewardship in the swine sector. Full article

This study examined the growth dynamics of Salmonella enterica and Listeria monocytogenes in two food matrices, cheddar cheese sauce (CCS) and salmon spreadable paste (SSP), and assessed the antimicrobial efficacy of freshly extracted essential oils (EOs) from Citrus limon cv. Femminello Santa Teresa (FST) compared with commercial (COM) EOs. Sensory sniffing tests indicated that lemon EOs were unsuitable for bio-preserving CCS. SSP supported rapid growth of both pathogens, whereas CCS caused an immediate and progressive population decline, highlighting strong matrix-dependent effects mainly related to pH. When applied to SSP, FST EOs significantly modified microbial behaviour, showing bacteriostatic activity against S. enterica and a rapid, irreversible bactericidal effect against L. monocytogenes, with complete inactivation within 24 h and no regrowth. In contrast, COM EOs showed weaker antimicrobial activity, producing limited growth reductions. SSP exhibited high growth potential (δ > 0.5) for both pathogens, with intra-species variability. FST EOs eliminated L. monocytogenes growth, yielding strongly negative δ values, while Salmonella δ values remained > 0.5, indicating reduced yet persistent growth. Throughout the experiments, pH and water activity (a_w) remained nearly unchanged after EO addition, confirming that inhibition depended on EO bioactivity rather than matrix modification. Overall, FST lemon EOs represent a promising preservation strategy for fish spreads. Full article