Search Results (922)

Treating bacterial infections has become increasingly difficult due to the rise in antibiotic-resistant bacterial strains. Strategies involving the targeted delivery of antibiotics have been proposed to minimize the administered antibiotic doses. This study aims to develop the first double-modified nanovehicle capable of increasing bacterial membranes’ permeability while specifically targeting Staphylococcus aureus, one of the foremost pathogens responsible for global mortality rates. Thus, polymeric NPs composed of poly(lactic-co-glycolic acid) (PLGA) were produced, and their surface was modified with TAT peptide to increase the membranes’ permeability and folic acid (FA) to direct the NPs to S. aureus. The nanosystem showed spherical morphology with sizes of 174 ± 4 nm, a monodisperse population (polydispersity index of 0.08 ± 0.02), and a zeta potential of −2.5 ± 0.1 mV. The NPs remained stable for up to four months during storage. Fluorescence-based flow cytometry analysis proved that the double modification of PLGA NPs increased the interaction of the NPs with S. aureus, with fluorescence increasing from 71 ± 3% to 87 ± 1%. The nanosystem slightly affected the growth curve of S. aureus by extending both the lag time (from 2.5 ± 0.2 to 2.88 ± 0.4 h) and the exponential phase, as evidenced by an increase in the half-maximum growth time (from 3.9 ± 0.2 to 4.4 ± 0.1 h). Furthermore, the nanocarrier showed no toxicity for human dermal fibroblast cells, maintaining a 100% cell viability at the highest concentration tested (100 µM). Therefore, the proposed FA/TAT-functionalized nanocarrier presented promising features to be successfully used as a delivery vehicle of antimicrobials to fight S. aureus. Full article

Post-harvest bacterial infections pose a serious threat to modern agriculture, resulting in substantial financial losses and environmental issues. Every year, microbial spoiling causes a significant loss in fruit and vegetable production, and traditional control techniques are frequently insufficient. This review highlights novel delivery systems such as edible films and coatings while analyzing recent developments in bacteriophage-based post-harvest disease management techniques. Bacterial resistance, environmental stability, and regulatory issues restrict the use of bacteriophages, despite their high specificity, biodegradability, and low environmental impact. Phage viability in storage and the field has increased thanks to developments in formulation technologies, such as encapsulation and stabilization. The review highlights the practical implementation of phage applications in post-harvest disease management, with a particular focus on innovative delivery systems as well as integrating legal and regulatory viewpoints. By bridging scientific innovation with legal and commercial considerations, this work offers an interdisciplinary foundation for advancing sustainable, phage-based approach. Full article

This study investigated the efficacy of different cryoprotectants (maltodextrin, skim milk, trehalose, sucrose, fructose, and dextrose) in protecting probiotic cultures isolated from the microbiota of arapaima (Arapaima gigas) (Enterococcus faecium CRBP46 and Enterococcus gallinarum CRBP19) during lyophilization, storage (−25 °C, 4 °C, and 25 °C for 120 days), and exposure to simulated gastrointestinal fluids (SGF). Cell surface hydrophobicity and the ultrastructural aspects of the coating matrices were also evaluated. Skim milk, trehalose, and dextrose (only for E. gallinarum) protected Enterococcus spp. against the negative effects of lyophilization, resulting in minimal viability loss (≤0.03 log CFU/g) and ≥99.50% survival. All cryoprotectants promoted stability (≥8.87 log CFU/g) for both bacteria when stored at refrigeration and freezing temperatures for 120 days. However, only skim milk maintained high viability (≥6.83 log CFU/g) for Enterococcus spp. during 120 days of storage at room temperature. Additionally, Enterococcus spp. lyophilized with skim milk demonstrated stability in SGF, with high cell viability (≥8.97 log CFU/g) and survival over 97%. Skim milk also significantly increased the cell adhesion capacity of Enterococcus spp., making them more hydrophobic. Scanning electron microscopy showed that Enterococcus cells were incorporated into the skim milk matrix and that its lower porosity directly contributed to the preservation of cell viability. Therefore, we conclude that skim milk is the most effective cryoprotectant under the tested conditions for E. faecium and E. gallinarum, as it ensured stability and high viability for both bacteria throughout all post-lyophilization challenges, maintaining bacterial concentrations above those suggested for probiotic formulations. Our findings provide unprecedented insights into the development of long-term stable, dry autochthonous probiotics, aiming to strengthen a more sustainable aquaculture for the arapaima, the Amazon’s giant fish. Full article

Sant’Agostino green table olives, traditionally processed in Apulia and flavoured with Foeniculum vulgare, represent a niche product whose microbial ecology remains largely unexplored. This study aimed to characterise the microbiota of the final product (both brine and fruit) after six months of storage with wild fennel. Four production batches were analysed using a combined culture-dependent and culture-independent approach. Microbiological counts revealed variable levels of aerobic mesophilic microorganisms, yeasts, lactic acid bacteria (LAB), and staphylococci, with yeasts and LAB being predominant. Ten LAB strains were identified, including Enterococcus faecium, Leuconostoc mesenteroides subsp. jonggajibkimchii, Leuconostoc mesenteroides subsp. cremoris, Leuconostoc pseudomesenteroides, Lactiplantibacillus plantarum, and Lactiplantibacillus pentosus. Yeast isolates belonged to Candida tropicalis, Torulaspora delbrueckii, and Saccharomyces cerevisiae. Amplicon sequencing (MiSeq Illumina) revealed distinct bacterial profiles between fruit and brine samples, with taxa from Actinobacteria, Bacteroidetes, Enterococcus, Lactobacillus, Leuconostoc, Alphaproteobacteria, Enterobacteriaceae, and other Gammaproteobacteria. Enterococcus and Leuconostoc were consistently detected, while Lactobacillus sensu lato appeared only in one fruit and one brine sample. These findings provide new insights into the microbial diversity of Sant’Agostino olives and contribute to the understanding of their fermentation ecology and potential for quality and safety enhancement. Full article

Korean melon (K-melon, Cucumis melo L. var. makuwa) is a key horticultural crop in the Republic of Korea, but its short shelf life restricts long-distance export. This study evaluated the modified atmosphere (MA) films of varying oxygen transmission rates (OTR) at controlled atmosphere (CA) storage under real maritime export conditions to Vietnam. In the non-permeable OTR 0 (Control) treatment, internal O₂ rapidly declined below the anaerobic compensation point (1.67% at 10d and 0.47% at 10+3d) while CO₂ accumulated to 32–36%. This ultra-low oxygen environment induced anaerobic metabolism, evidenced by strong accumulation of fermentative metabolites such as lactic acid, acetoin, and 2,3-butanediol, along with glucose/fructose retention and increases in alanine and γ-Aminobutanoic acid (GABA). These changes disrupted glycolysis and the Tricarboxylic acid cycle (TCA), consistent with CA shock, and were accompanied by rind blackening, elevated weight loss, and hue angle shifts toward yellow-orange. By contrast, OTR 10,000 and OTR 30,000 films significantly suppressed weight loss and color changes. Partial least squares-discriminant analysis (PLS-DA) identified volatile organic compounds, namely acetoin, 2,3-butanediol, and hexanal, as key discriminant metabolites, with OTR 30,000 clearly separated from other treatments at 10+3d, indicating minimal fermentation and oxidative stress. Microbial assays revealed a dose-dependent reduction in bacterial counts with increasing OTR, while fungal growth was most strongly suppressed under OTR 10,000. Overall, OTR 30,000 maintained the lowest and most stable levels of stress-related metabolites, minimized microbial proliferation, and preserved metabolic stability throughout shipping. This study provides the first quantitative evidence of anaerobic metabolic transition and primary metabolite accumulation in K-melons under actual export trials. The findings demonstrate that optimizing MA film permeability, particularly OTR 30,000 films, offers a practical and cost-efficient strategy to extend shelf life, maintain quality stability, and enhance the global export potential of K-melons. Full article

Soil salinization threatens soil organic carbon (SOC) sequestration. Although microbial necromass carbon (MNC) is crucial for SOC formation and stability, how biochar affects MNC in saline–alkaline soils remains unclear. This study assessed the impact of biochar amendment (0, 10, 20, and 30 t ha⁻¹) on SOC and MNC dynamics in saline–alkaline soils cultivated with Arundo donax cv. Lvzhou No. 1 across tillering, jointing, and maturity stages. Biochar amendment significantly enhanced SOC and the soil C/N ratio, with the highest dose (30 t ha⁻¹) raising SOC by 47.21% at jointing and 34.64% at maturity. Biochar significantly increased MNC at all growth stages, with increases ranging from 22.74% to 30.81%. From the jointing to the maturity stage, SOC exhibited a decline (20.03 to 27.77%), in contrast to the minimal change in MNC (–6.37% to 9.80%). This divergent trend consequently led to a peak in the MNC/SOC ratio at maturity. It directly demonstrates the relative stability of MNC and indicates its role as a persistent carbon reservoir within the topsoil. Biochar also elevated soil pH and nutrient availability, which reshaped microbial community structure and enhanced bacterial diversity. Partial least squares path modeling revealed that biochar facilitates MNC accumulation directly and indirectly by modifying soil chemical properties and thereby enhancing microbial diversity. These findings show that biochar enhances stable SOC storage in saline–alkaline soils primarily through the formation and stabilization of microbial necromass, thus revealing its potential for climate change mitigation. Full article

This study reports the development of chitosan-based (CS) films incorporating riboflavin (RF) as a natural photosensitizer to create sustainable, light-activated antimicrobial packaging materials. The films were prepared by solvent casting, and their photochemical behavior under blue LED light (450 nm) was investigated, including RF photodegradation kinetics and structural changes in the film-forming solution analyzed by ¹H NMR spectroscopy. Mechanical, thermal, optical, and barrier properties were also characterized to assess packaging suitability. Upon illumination, CS/RF films generated reactive oxygen species, particularly singlet oxygen (¹O₂), leading to visible color changes and significant antimicrobial activity against Pseudomonas fluorescens. Bacterial growth was reduced by up to 97% after 120 min of irradiation (0.92 J cm⁻²), with efficacy observed at both room temperature and 4 °C. The incorporation of RF did not alter the films’ mechanical properties, while thermal stability was preserved, optical transparency was modulated, and excellent oxygen barrier performance was maintained, although water vapor permeability remained moderate. These findings demonstrate that CS/RF films combine functionality and sustainability, offering a promising strategy for extending food shelf life through light-activated antimicrobial action. Validation under real storage conditions is recommended to confirm their potential in diverse food systems. Full article

Sustainable soil management requires striking a balance between productivity and soil health. While agroforestry practices are known to improve soil health and ecosystem functions, the contribution of microbial diversity to maintaining multifunctional soil processes in pecan (Carya illinoinensis) cultivation has yet to be fully elucidated. This study examined microbial diversity, soil functions, and multifunctionality across different pecan intercropping setups. We compared a monoculture pecan plantation with three agroforestry models: pecan–Paeonia suffruticosa–Hemerocallis citrina (CPH), pecan–P. suffruticosa (CPS), and pecan–P. lactiflora (CPL). We employed high-throughput sequencing (16S and ITS) to determine the soil bacterial and fungal communities and analyzed the species diversity, extracellular enzyme activities, and physicochemical properties. Soil multifunctionality (SMF) was evaluated using 20 indicators for nutrient supply, storage, cycling, and environmental regulation. Agroforestry increased soil fungal diversity and improved multifunctionality when compared to monoculture. The CPS and CPH models were the most beneficial, increasing multifunctionality by 0.74 and 0.55 units, respectively. Structural equation modeling revealed two key pathways: bacterial diversity significantly enhanced nutrient cycling and environmental regulation, whereas fungal diversity primarily promoted nutrient cycling. These pathways together delivered clear gains in multifunctionality. Random forest analysis identified key predictors (total nitrogen, total carbon, available potassium, β-1,4-N-acetylglucosaminidase, and alkaline phosphatase), highlighting the joint importance of nutrients and microbial enzymes. Our results demonstrate that selecting species in pecan agroforestry alters microbial communities and activates key functions that support soil health and long-term resilience. Hence, pecan agroforestry maintains SMF through microbial processes, with CPS showing the strongest effect. These results can inform species selection and encourage broader testing for resilient, biodiversity-based farming practices. Full article

The aim of this study was to find a way to remove persistent bacteria inhabiting in vitro shoot cultures of raspberry. Often, decontamination treatments fail to reach bacteria residing in internal tissues, leading to contaminated cultures later. Three raspberry cultivars, each harboring a unique bacterial contaminant, were used in this study. Experiments were conducted to assess the potential for eliminating these bacteria using biocide infiltration at 30 mbar. The following biocides were used: mercuric chloride (HgCl₂ at 0.05 and 0.1%), Plant Preservative Mixture (PPM^TM 0.2–4%), rifampicin (50–200 mg L⁻¹), and sodium hypochlorite (NaOCl 0.1–60%). Only 0.05 or 0.1% HgCl₂ applied via infiltration successfully eliminated all of the bacteria from the shoots, which remained bacteria-free for several years, as confirmed by indexing explants on bacterial media at each subculture. While most treated shoots became necrotic and died due to infiltration, the surviving shoots remained vital and provided bacteria-free material for long-term propagation. Results from experiments comparing micropropagation potential in bacteria-contaminated and bacteria-free cultures showed that bacteria-free shoots produced longer shoots, and the total number of shoots did not differ, except for ‘Norna’/Curtobacbacteria-free cultures, which were more productive. Bacteria-contaminated shoots rooted at higher percentages, but roots were much shorter, and plantlets initiated growth during acclimatization later. Cultures that were contaminated did not survive storage at 4 °C in the dark for 4–6 months. Full article

As a staple food, potato (Solanum tuberosum L.) (Solanaceae) is one of the most produced food crops to ensure food security. The potato tuber moth (PTM), Phthorimaea operculella (Zeller, 1873) (Lepidoptera: Gelechiidae), is a major pest of potato, damaging both the growing and storage processes. In recent years, green pest control strategies have been gaining importance to reduce the adverse effects of chemicals and protect the environment. Entomopathogenic nematodes (EPNs) and their bacterial endosymbionts (Xenorhabdus and Photorhabdus spp.) have been one of the top topics studied in sustainable pest control approaches. In the present study, the two most common EPN species, Steinernema feltiae and Heterorhabditis bacteriophora, and their bacterial associates, Xenorhabdus bovienii and Photorhabdus luminescens subsp. kayaii were evaluated against PTM larvae separately and in combination with spinosad. The survival rates of infective juveniles (IJs) of EPNs were over 92% after 72 h of direct exposure to spinosad. Co-application of EPNs and bioactive compounds (BACs) of endosymbiotic bacteria with spinosad induced synergistic interactions and achieved the maximum mortality (100%) in PTM larvae 48 h post-treatment. Spinosad and BAC combinations were highly efficient in controlling the PTM larvae and provided LT₅₀ values below 23.0 h. Gas chromatography mass spectrometry (GC-MS) analysis identified 29 compounds in total, 20 of which belonged to P. luminescens subsp. kayaii. The results indicate that the integration of EPNs and BACs of endosymbiotic bacteria with spinosad presents a synergistic interaction and enhances pest control efficacy. Full article

This study examined how storage influences the flavor profile and microbial composition of Suancai. To achieve this, we combined physicochemical measurements with analyses of both volatile and non-volatile metabolites, assessments of microbial diversity, and multivariate statistical modeling. Specifically, we investigated changes in physicochemical parameters, organic acids, amino acids, biogenic amines, volatile compounds, and microbial communities before and after storage. The results revealed that, after one year of storage, the pH and nitrite levels in Suancai decreased significantly, whereas the titratable acidity increased substantially. Among the organic acids, lactic acid and oxalic acid remained dominant both before and after storage. In terms of amino acid composition, glutamic acid, aspartic acid, and alanine were present in relatively high concentrations. A total of 69 volatile compounds were detected in Suancai, with esters and alcohols representing the major groups. Odor activity value analysis identified nonanal and phenethylaldehyde as key contributors to the overall aroma profile. Correlation analysis further indicated that Lactobacillus, Halomonas, and Chromohalobacter were the dominant bacterial genera linked to flavor development. Specifically, Lactobacillus exhibited strong positive correlations with phenylethanal, nonanal, ethyl octanoate, and ethyl decanoate, whereas Debaryomyces was positively associated with allyl isothiocyanate, 3-butenyl isothiocyanate, and ethyl ionone. Full article

Edible and medicinal plants provide a treasure trove of natural phytochemicals for mining the next generation of green food preservatives. Herein, we evaluated antibacterial activities of 55–95% ethanol extracts from the edible rhizome of Rumex madaio (RmEEs). The 75% ethanol extract displayed the strongest antibacterial activity, and its purified fraction 2 (RmEE-F2) blocked the proliferation of common pathogens Staphylococcus aureus and Vibrio cholerae, with minimum inhibitory concentrations (MICs) of 391 μg/mL. RmEE-F2 (1 × MIC) altered the bacterial cell surface biophysical parameters and impaired cell structure, resulting in intracellular nucleic acid and protein leakage. It manifested bacteriostatic rates of 88.21–91.17% against S. aureus and V. cholerae in spiked fish (Carassius auratus) and shrimp (Penaeus vannamei) during storage at 4 °C for 24 h. Meanwhile, RmEE-F2 effectively rendered the pH rising and reduced lipid oxidation and protein degradation of C. auratus and P. vannamei meat samples at 4 °C for 6 days. Additionally, RmEE-F2 (< 781 µg/mL) showed non-cytotoxicity to human colon Caco-2, liver HepG-2, and lung A549 cell lines, and rescued V. cholerae and S. aureus-infected Caco-2 cellcells with enhanced viability of 14.31–16.60% (1 × MIC). Comparative transcriptomic analysis revealed down-regulated protein synthesis, cell wall and cell membrane synthesis, and or DNA replication and repair in the tested bacteria triggered by RmEE-F2. The major antibacterial compounds in RmEE-F2 included melibiose (9.86%), 3-(N, N-dimethylaminomethyl) indole (7.12%), and citric acid (6.07%). Overall, this study underscores the promising potential of RmEE-F2 for aquatic product green preservation. Full article

This study investigated the effectiveness of a bacteriostatic-coated blister in preserving swine semen quality and its impact on reproductive performance. Two experiments were conducted: an in vitro assessment of the blister’s bacteriostatic efficacy and semen quality during three days of storage (Experiment 1), and a seven-day commercial farm trial evaluating its effect on reproductive outcomes in artificially inseminated gilts and sows (Experiment 2). In Experiment 1, the bacteriostatic blister effectively controlled bacterial proliferation, maintaining counts below 2 log10, comparable to controls with added antibiotics. Sperm quality parameters, including total and progressive motility, consistently exceeded the critical threshold for artificial insemination. Experiment 2 demonstrated that the bacteriostatic coating did not negatively affect key reproductive performance indicators, such as farrowing rate, total piglets born, or live piglets under commercial conditions. These findings suggest that the bacteriostatic-coated blister offers a viable, potentially antibiotic-free, alternative for semen preservation, extending storage viability for up to seven days. This technology supports sustainable reproductive practices, representing a significant advancement in commercial swine production. Full article

Artificial (technical) snow production is an increasingly common practice in alpine regions, yet little is known about its role in shaping microbial communities at the molecular level. In this study, we combined culture-based methods with high-throughput 16S rRNA gene sequencing and functional trait prediction (FAPROTAX) to investigate bacterial communities across the full technical snowmaking cycle in one of Polish ski resorts. The molecular profiling revealed that technical snow harbors dominant taxa with known cold-adaptation mechanisms, biofilm-forming abilities, and stress tolerance traits (e.g., Brevundimonas, Lapillicoccus, Massilia, with a relative abundance of 2.95, 2.14, 3.38 and 5.61%, respectively). Functional inference revealed a consistent dominance of chemoheterotrophy (up to 38% in relative abundance) and aerobic chemoheterotrophy (up to 36%), with localized enrichment of fermentation (6.9% in cannon filter and 6.5% in sediment) and aromatic compound degradation (3.7% in source waters, 3.8% in cannon filter and 4.6% in sediment). Opportunistic and potentially pathogenic genera (e.g., Acinetobacter, Flavobacterium, Nocardia) persisted in sediments (7.4%, 21.4% and 3.5%) and meltwater (34.9% and 2.31% for the latter two), raising concerns about their environmental reintroduction. Our findings indicate that technical snowmaking systems act as selective environments not only for microbial survival but also for the persistence of molecular traits relevant to environmental resilience and potential pathogenicity. Our study provides a molecular ecological framework for assessing the impacts of snowmaking on alpine ecosystems and underscores the importance of monitoring microbial functions in addition to taxonomic composition. Full article

Fermented beverages have been highlighted for their beneficial effects on health, especially due to the presence of probiotic microorganisms. This study aimed to develop and characterize a beverage fermented from the aqueous extract of licuri (Syagrus coronata) with grains of milk kefir and water kefir. Physical–chemical properties, microbial viability, storage stability, and in vitro resistance to the gastrointestinal tract (GIT), as well as microbiological safety and identification of isolated bacteria, were evaluated. The grains were fermented in licuri for 24 and 48 h, and the samples were compared with their respective controls. The analyses revealed that the licuri drink favored the growth of kefir grains, maintaining adequate microbial viability (>7 log CFU mL⁻¹ for lactic acid bacteria and >4 log CFU mL⁻¹ for yeasts), with good resistance to GIT (>60%) and physical–chemical properties for 20 days. The bacterial isolate was identified as Lacticaseibacillus paracasei, with a satisfactory safety profile. Licuri extract is therefore a promising matrix for the development of non-dairy functional beverages with potential probiotic properties. Full article