Search Results (1,048)

Phytopathogenic bacteria and fungi significantly reduce fruit and vegetable yields, resulting in substantial economic losses. Conventional management relies on synthetic agrochemicals; however, their intensive use poses risks to human health, environmental integrity, and biodiversity. Snake venoms have evolved under selective pressure, developing specialized components with potent antimicrobial properties as part of a defense mechanism against prey-borne microorganisms. This study evaluated the inhibitory potential of Micrurus venoms against pathogens of agricultural interest and developed bioactive gelatin-based films incorporated with purified L-amino acid oxidases (LAAOs) as a novel biocontrol strategy. Venoms from M. ancoralis, M. mipartitus, and M. dumerilii exhibited significant growth inhibition against Xanthomonas and Fusarium strains. The primary active component was identified as LAAO through biological activity and mass spectrometry. Biofilms were formulated by incorporating M. ancoralis venom and its purified LAAO into a gelatin matrix. Physicochemical and microbiological characterization, alongside in situ assays on strawberries, demonstrated that the functionalized biofilms retained potent antimicrobial activity. Furthermore, LAAO incorporation did not significantly alter the physicochemical properties of the fruit but effectively extended shelf life by reducing weight loss and maintaining sensory appearance. These findings highlight the biotechnological potential of elapid venom components in the development of alternatives for phytopathogen control and active food packaging. Full article

Plant extracts and microbiological supernatants were subjected to qualitative and compositional analyses to characterize their bioactive profiles and assess their potential agricultural applications. The garlic (Allium sativum) extract was rich in allicin and selected free amino acids, contained betulin as the dominant triterpene, and displayed a favorable elemental profile with high levels of potassium, phosphorus, sulfur, calcium, and magnesium, with no detectable heavy metals. Detectable amounts of B-group vitamins and vitamin E isoforms were also identified. Qualitative phytochemical screening confirmed the presence of saponins and flavonoids in the garlic extract. The Jerusalem artichoke (Helianthus tuberosus) extract exhibited a significantly higher total phenolic content compared to the garlic extract, with qualitative analysis confirming the presence of saponins, tannins, and flavonoids, suggesting a broader spectrum of bioactive compounds. The two bacterial supernatants were characterized by HPLC analysis and differed in their metabolic profiles: the Enterobacter sp. fermentation broth contained glycerol, 2,3-butanediol, and acetic acid, while the Paenibacillus sp. supernatant additionally contained lactic acid, ethanol, and succinic acid, reflecting distinct fermentation pathways. The in vitro and greenhouse studies aimed to evaluate biological preparations for controlling wheat diseases caused by fungi of the Fusarium genus as well as diseases affecting the stem base. Plant extracts (garlic—Allium sativum, Jerusalem artichoke—Helianthus tuberosus) and supernatants (fermentation broths) obtained with the Paenibacillus and Enterobacter bacteria were tested at three concentrations. In laboratory experiments, the degree of inhibition of the growth of the mycelium of the tested fungal species was determined, while in greenhouse studies, the effectiveness in limiting the development of stem base diseases and the impact of the applied biopreparations on plant growth were evaluated. Among the plant extracts, H. tuberosus demonstrated superior antifungal activity, achieving up to 100% inhibition of R. cerealis mycelial growth at 10% concentration and reducing disease severity by 34.3% compared to the untreated control under greenhouse conditions. Paenibacillus sp. supernatant demonstrated strong in vitro antifungal activity. The results indicate that H. tuberosus extract represents a promising candidate for further field evaluation as a component of sustainable wheat protection programs. Full article

This study evaluated a post-cut treatment combining sanitization, carboxymethylcellulose (CMC) coating, and chokeberry pomace extract for preserving fresh-cut sweet peppers during 7 days of refrigerated storage. Sliced peppers of two cultivars, Sunny F₁ (yellow) and Yecla F₁ (red), were assigned to five treatments: water washing (control), BioActiW 2000 Food sanitizer (BAW), BAW followed by CMC coating (BAW + CMC), CMC coating with 3.5% chokeberry extract (CMC + AE), and 3.5% aqueous chokeberry extract (AAE). Samples were stored at 5 ± 1 °C and assessed for physicochemical, microbiological, sensory, and postharvest quality attributes. The response was cultivar-dependent. Coating-based treatments reduced polyphenol and L-ascorbic acid contents, although chokeberry-containing formulations mitigated these losses relative to BAW + CMC. Total sugars and carotenoids were not significantly affected. In both cultivars, BAW and BAW + CMC best limited mesophilic bacteria and yeast growth, reduced softening, and decreased weight loss. AAE applied without prior sanitization increased microbial counts in Sunny F₁. Sensory analysis showed cultivar-specific acceptance: Sunny F₁ tolerated CMC + AE and BAW + CMC better, whereas Yecla F₁ was more sensitive to off-flavors linked to the extract. These results indicate that sanitization is essential for microbiological stability, while CMC can provide an additional barrier effect. Chokeberry pomace extract showed mixed effects and appears to be a formulation component whose usefulness depends on cultivar and treatment conditions. Full article

Understanding the interaction between plants and rhizosphere microorganisms is critical for the development of biofertilizers. Fluorescent labeling of rhizosphere microorganisms serves as a key strategy to track their behavior during plant–microbe coculture. However, most newly isolated strains are novel and lack available molecular tools for such studies. In this research, Planococcus dechangensis NEAU-ST10-9^T (P. dechangensis NEAU-ST10-9^T), a salt-tolerant strain, was obtained from the China General Microbiological Culture Collection Center (CGMCC). It significantly increased maize root length by approximately 1.56-fold. To investigate the underlying mechanism, a donor strain (Ec102) and a shuttle plasmid (pAS104) were engineered to mediate conjugation with P. dechangensis NEAU-ST10-9^T and drive GFP overexpression in the bacterium, generating the genetically labeled strain Pd103. The fluorescence intensity (expressed as GFP/OD₆₀₀, arbitrary units) of Pd103 increased with bacterial growth and was approximately tenfold higher than that of the wild-type strain after 16 h of culture. Following inoculation onto maize seeds, confocal microscopy analysis revealed that Pd103 colonized the epidermis and endodermis of maize roots. These results indicated that P. dechangensis NEAU-ST10-9^T could invade maize roots and promote maize seedling growth. In summary, we have successfully established a robust fluorescence labeling and tracking system tailored for P. dechangensis NEAU-ST10-9^T, which constitutes a valuable tool for elucidating the cellular and molecular mechanisms governing its plant–microbe interaction. Full article

The increasing volume of plant-based waste generated by the agri-food sector represents both an environmental challenge and an underexploited biotechnological resource. These wastes, rich in lignocellulosic compounds, constitute a natural habitat for specialized microorganisms. The aim of this article is to provide a critical review of the potential use of such wastes—specifically straw, pomace, and manure—in two complementary ways: (1) as a specific source for isolating new microbial strains with high biodegradation capacity and plant-growth-promoting potential, and (2) as a low-cost substrate for their propagation, e.g., in solid-state fermentation processes. This dual perspective represents a novel, integrative approach, as previous reviews typically address these aspects in isolation rather than considering their synergistic potential. The article discusses the relationship between the chemical composition of selected wastes (straw, pomace, manure) and the targeted selection of desirable microbiological traits. Particular emphasis is placed on advanced, integrated approaches for assessing microbial potential, combining phenotyping (zymography, activity assays), genomics (whole-genome sequencing—WGS, identification of CAZyme genes and biosynthetic gene clusters), and metabolomics (metabolite profiling, 3D MSI imaging). The limitations of individual methods are critically evaluated, and key research gaps are identified, including the need for in situ validation of omics-based findings and the development of stable microbial consortia with predictable performance under variable environmental conditions. These gaps are discussed in the broader context of circular bioeconomy and sustainable agriculture, highlighting the strategic relevance of integrating waste valorization with microbiome-based biotechnological innovations. Full article

The use of protective cultures and probiotic lactic acid bacteria is considered a potential strategy for controlling Listeria monocytogenes in food systems, particularly in minimally processed and fermented products. However, the behavior of foodborne pathogens in complex dairy matrices, especially those enriched with byproducts of milk processing, remains insufficiently characterized. The aim of this study was to evaluate the survival of Listeria monocytogenes in buttermilk enriched with retentate obtained after microfiltration, in the presence of the probiotic strain Lactobacillus acidophilus LA-5^®. The study was conducted under different storage temperatures to reflect realistic conditions of product distribution and storage. The results demonstrated that fermented buttermilk with added retentate did not support the growth of Listeria monocytogenes under the tested conditions, and a gradual reduction in pathogen counts was observed during storage. The presence of Lactobacillus acidophilus LA-5^® was associated with a faster decrease in pathogen levels compared to samples without the probiotic strain. At the same time, lactic acid bacteria maintained high viability throughout the storage period. In contrast, predictive modelling using ComBase indicated the potential for pathogen growth under similar physicochemical conditions. This discrepancy highlights the limitations of predictive models when applied to complex, biologically active food matrices. These findings indicate that fermented buttermilk enriched with retentate may provide conditions limiting the survival of L. monocytogenes. However, the mechanisms responsible for the observed inhibition were not directly investigated in this study and require further research. The results emphasize the importance of experimental validation of predictive microbiology models and contribute to a better understanding of pathogen behavior in fermented dairy systems. Full article

Fish-derived products are extensively acknowledged for their substantial role in fostering balanced diets and supporting a healthy way of life. This research is aimed at formulating, analyzing and evaluating a fish-based food product. The methodology adopted in this study adheres to contemporary food safety standards, prioritizing the utilization of minimal technological processes and natural ingredients, a focus that is gaining prominence within contemporary industrial practices. Thus, the proposal for a formulation obtained by integrating powders and extracts from plant byproducts (Citrus) represents a concrete application direction with real potential for commercialization. The product has been enriched with biocomponents derived from orange peel, namely orange extract (OE) and orange peel powder (PPO). The research focused on product development and the in situ evaluation of the effects of OE and PPO. The physicochemical composition, bioactive compound content, and antioxidant activity were evaluated, along with the microbiological status under post-opening refrigeration conditions, in order to simulate actual consumer use. In addition, the product’s color parameters and sensory attributes were analyzed. The results highlight significant potential for the development of a clean-label fish-based product, characterized by a simplified and easily implementable formulation, aligned with current production and consumption requirements. Compared to the control sample, both OE and PPO significantly influenced the analyzed parameters. Differences in physicochemical composition were observed in the experimental samples. In addition, PPO increased the antioxidant activity of the samples and the profile of bioactive compounds. Microbiological analysis, performed on day 0 and after 3 and 7 days of storage at 4 °C showed opening, confirmed the absence of Escherichia coli and Staphylococcus aureus in all samples and had an influence on the growth of fungi. The acceptability of fish-based products is often limited by odor perception, which is one of the main factors leading to consumer rejection. Sensory evaluation demonstrated that citrus-enriched samples were distinguished by the perception of particular sensory attributes. This formulation presents a practical solution to address this constraint, thereby enhancing the product’s sensory acceptability. The integration of OE and PPO yielded a more harmonized sensory profile, as evidenced by elevated hedonic scores and an intermediate placement in both principal component analysis (PCA) and external preference mapping. This research furnishes a thorough characterization of a fish-based food product, underscoring its potential as a viable option for balanced dietary regimens. Simultaneously, the findings support the product’s adherence to sustainability principles through the utilization of bioactive compounds sourced from plant byproducts, thus satisfying contemporary requirements for foods that possess an optimal nutritional profile and a diminished environmental footprint. Full article

Yaks (Bos grunniens) on the Qinghai–Tibetan Plateau face severe nutritional limitations during the dry season due to dependence on highly lignified, low-quality roughage. Identifying safe and effective rumen regulators capable of enhancing fiber utilization in this species is therefore of great practical importance. This study employed a two-pronged approach integrating in vitro mechanistic investigation and in vivo validation to evaluate the effects of the amphoteric surfactant cocamidopropyl betaine (CAPB) on rumen fermentation, the micro-spatial distribution of digestive enzymes, apparent total tract digestibility, and the macroscopic growth performance of yaks. In the in vitro fermentation trial (Experiment 1), a randomized block design was employed where a straw-based high-forage diet was used as the substrate and supplemented with 0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0% CAPB (based on substrate dry matter, DM) for a 48 h batch culture. The results showed that as the CAPB supplementation level increased, cumulative gas production, the degradation rates of DM and neutral detergent fiber (NDF), and the yields of total volatile fatty acids and microbial protein all exhibited significant quadratic responses (p < 0.05), peaking at the 0.5–1.0% supplementation levels. Concurrently, CAPB significantly promoted the transfer and release of carboxymethyl cellulase and xylanase into the free liquid phase (p < 0.01). In the in vivo validation trial (Experiment 2), 24 healthy growing male yaks (initial body weight 131.2 ± 8.4 kg) were allocated in a completely randomized design to four groups and fed a basal diet supplemented with 0, 0.5, 1.0, or 2.0% CAPB for 44 days. The results indicated that, while maintaining a stable DM intake, the addition of 0.5% CAPB significantly increased the average daily gain (ADG) of yaks (p < 0.05), improved the feed-to-gain ratio, and significantly enhanced the apparent total tract digestibility of NDF and ether extract (p < 0.05). However, when the supplementation dose exceeded the safety threshold (≥2.5% in vitro and ≥2.0% in vivo), both fermentation parameters and growth advantages declined. In conclusion, under the present experimental conditions, 0.5% CAPB improved roughage fermentation efficiency, putatively through an ‘enzyme elution’ mechanism, and was associated with macroscopic improvements in NDF and EE apparent digestibility and ADG in growing yaks. These findings identify 0.5% CAPB as a promising candidate rumen regulator for improving roughage utilization in growing yaks; broader generalization will require larger-scale and longer-duration trials. Full article

Ethical slaughter practices for crustaceans remain poorly standardized, and their effects on product quality and consumer perception are insufficiently understood. This study evaluated four ice-slurry-based slaughter methods in Penaeus vannamei reared under intensive biofloc technology (BFT) and their impact on refrigerated shelf life. While BFT enhances farming sustainability, it may an increase in microbial load, potentially shaping post-mortem spoilage. Shrimp were subjected to cold thermal shock in seawater ice slurry (C-TS); a 5 min immersion in chilled seawater with 50 ppm sodium hypochlorite, followed by TS (5BTS); 3–4 h of intestinal clarification, followed by 1 min immersion in chilled seawater with 50 ppm sodium hypochlorite and subsequent TS (C1BTS); and TS, followed by UV-C exposure (TS-UV). Over 12 days at <4 °C refrigeration, culture-based microbiology (mesophilic bacteria, enterobacteria, psychrotrophs, pseudomonas, and specific spoilage organisms), total volatile nitrogen compounds (TVB-N), melanosis, and qualitative descriptive analysis were performed. Storage time showed typical spoilage patterns driven by psychrotrophic bacteria, TVB-N, and melanosis. Slaughter method influenced quality: C1BTS limited psychrotroph proliferation but accelerated melanosis, and TS-UV yielded the poorest performance. Notably, 5BTS delayed melanosis (~3 days), maintained sensory quality, and avoided excessive microbial growth, making it the most effective method. These findings provide practical guidance for additive-free shrimp processing and identify psychrotrophs as key spoilage indicators in BFT systems. Full article

The agricultural sector generates substantial waste that harms both the environment and human health. This study aimed to utilise Metschnikowia yeasts to convert native agricultural wastes without chemical pretreatment. Ten Metschnikowia isolates were assessed using API tests to identify their assimilation profiles and enzymatic activities. Yeast growth was evaluated via the plate count method. The culture media containing molasses, brewery spent grain, and postharvest sunflower parts were characterised chromatographically, and the in vitro impact on Verticillium tenerum phytopathogen was evaluated. The effect of the yeast preparations on Caco-2, IEC-6, and HaCaT cell lines was also investigated. Solid waste materials without preliminary chemical pretreatment supported yeast multiplication to 4.5 × 10⁷–1.3 × 10⁸ CFU/mL. The metabolite composition and enzymatic activity of lipase, glucosidase, and protease in post-culture media suggest that they may act as growth inhibitors of the Verticillium strain. For post-cultivation samples, inhibition coefficients were equal to 1.24–2.00, depending on the kind of substrate and yeast strain used. Antimicrobial activity was also noted in cell-free samples after yeast cultivation on sunflower stalks and brewery spent grain. The toxicological analysis showed that the yeast preparations did not cause toxic effects on the tested cell lines. This research offers a sustainable approach using Metschnikowia yeasts, highlighting the importance of a holistic method that combines microbiological, biochemical, and toxicological aspects for sustainable waste management and the development of new applications, such as feed supplements and biocontrol agents. Full article

Caraway essential oil (CEO) and chitosan-based nanoparticles incorporating CEO (CNPs CEO) were evaluated as natural preservatives for fresh pork sausages stored at +4 °C for five days. The chemical composition of CEO was characterized by gas chromatography–mass spectrometry (GC/MS) and gas chromatography with flame ionization detection (GC/FID); carvone (92.5%) and limonene (5.8%) were identified as dominant components. Eight experimental treatments were applied: control, CEO at 0.2, 0.4, and 0.6 mg/g, chitosan nanoparticles (CNPs), and CNPs CEO at 0.2, 0.4, and 0.6 mg/g. Encapsulation efficiency of CEO in chitosan nanoparticles was 67.7 ± 1.91%. Microbiological quality (total bacterial count (TBC), lactic acid bacteria, yeasts and moulds), lipid oxidation (TBARS), pH, and sensory attributes of raw and thermally processed sausages were monitored throughout storage. CEO reduced microbial growth and lipid oxidation in a concentration-dependent manner, while CNPs CEO formulations showed markedly superior performance. The CNPs CEO 0.6 mg/g treatment achieved the greatest inhibitory effect on all microbiological parameters, reducing TBC for 1.6 log CFU/g and limiting lipid oxidation, yielding final malondialdehyde values of 1.15 mg MDA/kg, approximately 50% lower than the control (2.18 mg MDA/kg). Sensory evaluation indicated that CNPs CEO-treated sausages maintained acceptable colour, odour, juiciness, texture, and overall acceptability throughout the storage period. The sample treated with CNPs CEO 0.6 mg/g remained above the acceptability level for all analyzed parameters for 5 days of storage, while the control became unacceptable for lipid oxidation on the fifth day and sensory unacceptable after the third day. These findings demonstrate that the application of CNPs CEO in sausage production enhances their stability, shelf life, and sensory characteristics, indicating a promising no-additive strategy in the industrial production of fresh pork sausages. Full article

ESKAPE pathogens represent a critical threat to global health. This challenge necessitates the development of novel antibacterial strategies. We investigated the antimicrobial potential of NK-92 cells and their derived large extracellular vesicles using flow cytometry, ELISA, confocal microscopy and microbiology assays. Here, we show that both NK-92 cells and NK-92-derived LEVs can interact with bacteria, as confirmed by confocal microscopy and flow cytometry. This interaction is associated with inhibition of colony formation. A possible mechanism can involve defensin-α1 secreted by NK-92 and packed in their LEVs. NK-92-derived LEVs can modulate S. aureus viability, colony growth and clindamycin susceptibility. These findings suggest NK cell-derived LEVs as promising strategies to combat multidrug-resistant bacterial infections. Full article

Background: Microbial contamination of fresh beef remains a major challenge in the meat industry, driving the need for effective natural preservation strategies that can extend shelf life while meeting consumer demand. Methods: Chitosan-based edible coatings enriched with free and nanoencapsulated Ocimum basilicum L. essential oil at concentrations of 0.25%, 0.5% and 1% were evaluated for their efficacy on fresh beef during 20 days of refrigerated storage. Microbiological parameters, including total bacterial count, lactic acid bacteria, psychrotrophic bacteria, and Pseudomonas spp., as well as physicochemical indicators such as pH and thiobarbituric acid reactive substances, were monitored at regular intervals throughout storage. Results: All active coatings significantly retarded microbial growth and lipid oxidation compared to the uncoated control (p < 0.05), with effects being concentration-dependent. Nanoencapsulation was achieved with an efficiency of 74%, and all formulations consistently showed better results compared to free essential oil coatings at equivalent concentrations. Application of a chitosan coating with 1% nanoencapsulated essential oil reduced total viable count by 1.5 log CFU/g and lactic acid bacteria by 0.7 log CFU/g, with the most pronounced effect observed for Pseudomonas spp. (1.9 log CFU/g reduction). In the same sample, MDA content remained below the threshold level until the end of storage. Additionally, sensory analysis indicated that the use of nanoparticles significantly improved the overall acceptability of the coated beef. Conclusions: These findings confirm that chitosan–basil nanoparticle coatings represent a promising natural alternative to conventional preservatives for improving microbiological safety and extending the shelf life of fresh beef. Full article

This study aimed to develop a biotechnological process for producing a lactic-fermented tomato ingredient (Solanum lycopersicum) capable of acting as a natural reddish colorant and enhancing microbiological stability in fresh pork sausage, reducing dependence on cochineal carmine, whose market price has fluctuated substantially. The bioprocess was conducted at industrial scale using a 10% tomato flour solution subjected to enzymatic hydrolysis with pectinases to release lycopene, followed by co-culture fermentation with Lacticaseibacillus paracasei ATCC 25302 and Pediococcus acidilactici ATCC 8042 to convert sugars into lactic acid. The antimicrobial potential of the ingredient was assessed through minimum inhibitory concentration assays using the Computational Microbial Density Scanning method against microbiota isolated from fresh pork sausage. A dose-dependent inhibitory effect was observed, with significant growth reduction from 2%. The fermented ingredient was then applied at 2% (w/w) in fresh pork sausage, partially or fully replacing cochineal carmine. Instrumental color analysis showed that 2% enabled a 50% reduction in cochineal carmine without compromising color. Microbiological stability evaluated using the MicroLab_ShelfLife method revealed a substantial reduction in microbial growth rates in treated groups. Overall, lactic-fermented tomato can partially replace cochineal carmine while preserving sensory color and providing an antimicrobial function, thereby enhancing product stability and shelf-life. Full article

Quorum Quenching (QQ) is a mechanism that disrupts Quorum Sensing (QS) signaling systems, which regulate gene expression based on bacterial population density. Many fish pathogens, such as Aeromonas, utilize QS systems to regulate the expression of their virulence factors. Disrupting these systems using QQ is a promising approach for infection control in aquaculture and may provide a safe alternative to antibiotics. Therefore, identifying microorganisms with QQ activity is a relevant task in agricultural microbiology and veterinary medicine. This study examines the identification of isolates with QQ activity in the microbial community of perch and assesses their probiotic potential for the prevention of aeromonosis. In this study, we isolated 32 strains of microorganisms capable of degrading N-acylhomoserine lactone (AHL), six of which exhibited stable QQ activity. Five strains were found to belong to the genus Rhodococcus, and one strain to the genus Exiguobacterium. The selected strains were tested for the enzymatic/non-enzymatic and intra-/extracellular QQ activity, pathogen growth inhibition, biofilm formation, and hemolytic activity, as well as growth ability under various environmental conditions (salinity, pH, bile acids, and temperature). Based on the results of these tests, the R. erythropolis PFS1.20 strain was selected as the most promising probiotic. The genomic analysis revealed that the studied strain contains genes encoding QQ enzymes, siderophore biosynthesis clusters, osmoprotectors, and compounds with antimicrobial properties. These results indicate the high probiotic potential of the R. erythropolis PFS1.20. Full article