Search Results (1,238)

Tenacibaculosis is a major bacterial disease in aquaculture, with Tenacibaculum discolor being characterized as one of the causative agents. This study evaluated the antimicrobial and antibiofilm potential of three isolated Pseudoalteromonas strains—Pseudoalteromonas sp. GY795-2 (deep-sea), Pseudoalteromonas spongiae MB2 (aquaculture installation), and Pseudoalteromonas tetraodonis SAE 20 (kelps)—against T. discolor strain FMCC B487. Cell-free supernatants (SNs) from each Pseudoalteromonas culture were tested in microtiter assays, assessing planktonic growth measured by OD₆₀₀ and biofilm biomass quantified by crystal violet (CV) staining. The addition of the Pseudoalteromonas SNs affected both growth and biofilm development of T. discolor strain FMCC B487. A significant decrease in T. discolor strain FMCC B487 growth and biofilm was observed in the presence of P. spongiae MB2 SN, whereas the SN of Pseudoalteromonas sp. GY795-2 promoted both growth and biofilm development of T. discolor strain FMCC B487. To assess whole-cell activity, dual-species biofilms were formed on plastic surfaces. After 24 h, all three Pseudoalteromonas strains reduced the viable T. discolor strain FMCC B487 population while maintaining their own cell numbers comparable to single-culture controls, suggesting an inhibitory interaction. These results demonstrate that these Pseudoalteromonas strains’ metabolites and cells can modulate T. discolor growth and biofilm development, highlighting their potential as biocontrol agents in aquaculture. Full article

Several Fusarium species have demonstrated the ability to thrive in saline soils and to tolerate or prefer high salt concentrations. In this context, the potential halophilic or halotolerant lifestyle of Fusarium pseudograminearum was investigated. Four isolates (3B, PVS-Fu 7, ColPat-1, and CBS 109956) were grown at different temperatures (10, 15, 20, 25, 30, and 35 °C) and NaCl concentrations (0, 7, 14, 21, and 28 g L⁻¹), and daily growth, mycotoxin production, and K⁺ and Na⁺ accumulation within hyphae were assessed. All F. pseudograminearum isolates exhibited strong adaptability to saline conditions, with significantly enhanced growth in the presence of NaCl. All isolates accumulated Na⁺ within their hyphae while retaining K⁺. The production of deoxynivalenol (DON) and zearalenone (ZEA) was generally suppressed following NaCl exposure, consistent with the known inhibitory effect of reduced water activity on mycotoxin biosynthesis. However, at 22 °C, two isolates, 3B and CBS 109956, showed no significant differences in ZEA production between the control (no salt) and the medium containing the lowest NaCl concentration tested (7 g L⁻¹). Notably, isolate 3B, obtained from the halophyte Salicornia europaea, retained the highest levels of both Na⁺ and K⁺ within hyphae and showed the greatest overall adaptation to salinity. These results confirm the hypothesis that the ability of F. pseudograminearum to colonize and infect a halophytic host is indicative of a halophilic lifestyle. In the context of increasing soil salinization, these findings help identify conditions that permit pathogen persistence without hazardous mycotoxin accumulation. Full article

Protective cultures are an increasingly industrially relevant biopreservation tool for meat and meat products, responding to simultaneous demands for microbiological safety, extended shelf life, and reduced reliance on synthetic preservatives within clean-label frameworks. This review summarizes current advances in protective cultures applied to meat systems, with emphasis on technological functions, efficacy boundaries, and safety-related due diligence. We discuss the dominant inhibitory mechanisms of lactic acid bacteria and related protective taxa—acidification, competitive exclusion, and antimicrobial metabolites (including bacteriocins)—and highlight why performance is strongly strain- and matrix-dependent under realistic storage conditions. Practical applications are reviewed across raw meats (spoilage delay under refrigeration and vacuum/MAP) and processed or ready-to-eat products, where post-processing surface application emerges as a critical control point for limiting Listeria monocytogenes outgrowth during chilled storage. Key implementation constraints include technological compatibility and sensory neutrality, which are influenced by product buffering capacity, salt content, available fermentable substrates, packaging atmosphere, and temperature. From a safety perspective, we synthesize evidence on antimicrobial resistance in food-associated cultures and outline contemporary qualification strategies combining phenotypic susceptibility testing with genome-based screening to exclude acquired and potentially transferable resistance determinants. Overall, protective cultures should be viewed as a targeted hurdle integrated into holistic preservation systems rather than a standalone substitute for hygiene and process control. Full article

The increasing demand for food is the driving force behind the search for novel, more selective, and less hazardous agrochemicals. Natural products are gaining prominence recently due to the promise of being green agrochemicals, but many natural products are poorly soluble in water, which reduces their applicability. In this work, we successfully formulated a water-insoluble Saussurea lappa root extract into a stable aqueous suspension using xanthan gum. The colloidal suspension was characterized by rheology, dynamic light scattering, and zeta potential. The results demonstrated that the suspension is a stable, sprayable, shear-thinning viscoelastic system (weak gel). A series of S. lappa solutions with xanthan gum were prepared and tested against five plant species, observing the inhibitory effect on the shoots and roots. The results were also compared with the commercial herbicide Dual. The S. lappa extract presented results comparable to or even greater than Dual for Lactuca sativa, Cucumis sativus, Brachiaria decumbens, and Bidens pilosa. However, it showed low inhibitory activity for Sorghum bicolor, highlighting its potential for selective weed control. This work illustrates xanthan gum as an effective vehicle for formulating insoluble natural products and demonstrates that S. lappa extract is a promising candidate for developing novel herbicides. Full article

Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most devastating diseases affecting global rice production. Plant essential oils (EOs) have been considered as a promising green alternative to synthetic fungicides. In this study, the antifungal activities of five plant EOs—Acorus calamus, Citrus reticulata, Syzygium aromaticum, Paeonia suffruticosa, and Melaleuca viridiflora—against M. oryzae were evaluated using the mycelial growth rate method. Among them, A. calamus EO (ACEO) exhibited the most pronounced inhibitory effect, with an EC₅₀ value of 0.37 μL/mL. It significantly delayed or inhibited conidial germination and appressorium formation. At higher concentrations (≥1 μL/mL), it also caused morphological abnormalities in appressoria. Observations by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the EO treatment caused hyphal surface wrinkling, cell wall thinning, organelle dissolution, and vacuolation. Pathogenicity tests further confirmed that ACEO reduced the virulence of the fungus remarkably, with nearly complete loss of pathogenicity at a concentration of 1 μL/mL. Finally, ACEO was analyzed using gas chromatography-mass spectrometry (GC-MS). The most abundant constituents identified were β-asarone (19.83%) and isoshyobunone (14.92%). Together, these findings demonstrate that ACEO impairs fungal pathogenicity by disrupting hyphal morphology and cellular integrity, highlighting its potential as an effective and eco-friendly fungicide for controlling rice blast. Full article

Pre-emergence control is one of the critical steps in the agricultural production of direct-seeding rice. To investigate the mechanism of pre-emergence flame control, a flame control test bench and a flame control and sowing integrated operation machine were designed and made. The experimental results demonstrate that tall fescue seeds achieved complete inactivation (100% rate) when exposed to a target temperature of 140 °C for 1 min. A temperature distribution analysis revealed that the 1 mm soil layer exhibited a lower temperature rise compared with the surface layer, while the 2 mm layer recorded the minimum temperature elevation. Among the tested nozzle–soil distances, 150 mm significantly improved the soil-heating efficacy over 200 mm, with 100 mm yielding the optimal performance. Statistical analysis confirmed that the nozzle–soil distance, seed burial depth, and operating speed exerted highly significant (p < 0.01) effects on the tall fescue seed inactivation rate. The seed burial depth emerged as the most influential factor, followed by the operating speed and nozzle–soil distance. Data from the field experiment further revealed a speed-dependent decline in the inactivation rates: 80.27% at 3 km·h⁻¹, 66.30% at 4 km·h⁻¹, and 46.10% at 5 km·h⁻¹, and SPSS analysis indicated that there were extremely significant differences between every pair of groups of data (p < 0.01). This study verified that pre-emergence flame control technology can effectively eliminate grass seeds on the soil surface and has a certain inhibitory effect on shallow-buried seeds, which contributes to the advancement of pre-emergence control technology. Full article

Thymus, Satureja, and Monarda are three plant genera, belonging to the Lamiaceae family, that are particularly valued for their essential oils (EOs) abundant in phenolic terpenoids. In this study, a botanical characterization of the following eight Eastern European cultivars (some of them newly bred) grown in Ukraine is distinguished: Thymus vulgaris (‘Yalos’, ‘101’), Thymus richardii (‘Fantasia’), Satureja montana (‘Krymsky smaragd’, ‘Lunata’, ‘4-18’), Monarda fistulosa (‘Premiera’), and Monarda × hybrida hort., which is a Monarda didyma × Monarda fistulosa hybrid (‘Tonya’). The EO of those cultivars was obtained and characterized in detail using GC-MS and GC-FID. Additionally, some biological activities of these oils were tested. Antimicrobial activity was verified against Escherichia coli, Staphylococcus aureus, and Candida albicans using disk diffusion and microdilution methods. Furthermore, some preliminary tests were performed on the motility of bull sperm using the CASA system. All the Thymus cultivars were very rich in thymol (57.99–67.62%), and all the S. montana cultivars were very abundant in carvacrol (62.22–75.53%). M. fistulosa cv. ‘Premiera’ contained mainly thymol (49.87%), and M. × hybrida cv. ‘Tonya’ contained both thymol (46.70%) and carvacrol (10.37%). All the tested EOs, as well as thymol and carvacrol, exhibited strong antibacterial and antifungal action with minimal inhibitory concentrations ranging from <0.25–0.5 mg/mL for Satureja, through <0.25–0.5 mg/mL for Monarda, to 0.5–4 mg/mL for Thymus. The EOs, at a concentration of 0.4 µL/mL, exhibited cytotoxicity towards bull spermatozoa when compared to the control sample. Full article

(1) Background: Listeria monocytogenes (Lm) is recognized by the World Health Organization (WHO) as one of the four principal foodborne pathogens. This study aimed to investigate the molecular characteristics of Lm isolates from Jiaxing, China, using whole-genome sequencing (WGS) to enhance our understanding of their molecular epidemiology. (2) Methods: A total of 39 foodborne Lm isolates and 7 clinical Lm isolates were analyzed via WGS to identify resistance genes, virulence factors, lineage, sequence type (ST), and clonal complex (CC). Antibiotic susceptibility was assessed using Minimum Inhibitory Concentration (MIC) testing, and serotypes were confirmed via multiplex PCR. (3) Results: We found that 39 food isolates were mainly lineage II (66.67%), with 13 STs; ST8 was the dominant ST, and 2 new types, ST3210 and ST3405, were found. Among the seven clinical isolates, lineage I was dominant (57.14%), and ST87 was the dominant ST. Serotype 1/2a was dominant, accounting for 54.35%, followed by 1/2b, which accounted for 36.96%. The overall antimicrobial resistance rate was 13.04%, with a multidrug resistance rate of 2.17%. All strains harbored LIPI-1 and LIPI-2, and five strains carried LIPI-3 genes: one strain belonged to ST619 of lineage I, two strains belonged to ST224 of lineage I, and two strains belonged to ST11 of lineage II. (4) Conclusions: This study clarified the genotype and serotype characteristics of Listeria monocytogenes in Jiaxing, as well as their molecular characteristics relating to drug resistance and virulence, thus providing a technical basis for improving exposure risk assessment of Listeria monocytogenes. Continuous monitoring, prevention, and control are recommended to further improve regional public health and safety. Full article

Objective: To better define potential executive function difficulties in individuals living with HIV but not clinically identified as having HAND, with and without mild to moderate cocaine dependence (CD), our cross-sectional study examined executive function performance on the Stroop Color-Word Test (Stroop) and the Trail Making Test (TMT) in four groups stratified by HIV and CD status. Method: We recruited 101 participants (26 HIV+/CD+; 18 HIV+/CD−; 30 HIV−/CD+; 27 HIV−/CD−). We utilized a 2 (HIV: yes/no) × 2 (Cocaine: yes/no) MANCOVA while controlling for age and premorbid intelligence on the Stroop trials (i.e., color-naming, word-reading, interference), and TMT-A and TMT-B z-scores, number of errors, and the B/A ratio. Results: HIV was associated with significantly slower performance on the Stroop Interference (p = 0.012, η² = 0.064). CD showed a trend towards slower performance on interference trials (p = 0.061, η² = 0.037) and was associated with significantly more errors on the Stroop Word-Reading (p = 0.028, η² = 0.050) and Interference trials (p = 0.046, η² = 0.041), suggestive of difficulties with inhibitory control and written language processing. There were no significant HIV × Cocaine interactions. Conclusions: Our results suggest HIV without clinically identified cognitive impairment and CD are associated with distinct and potentially overlapping executive functioning deficits, particularly for measures of inhibitory control. Notably, CD showed trend-level slowing on Stroop Interference performance, suggesting partial overlap with HIV effects. Clarifying the specific cognitive processes impacted by HIV and CD can help guide tailored interventions to improve functional outcomes in these populations. Full article

Bacterial contamination remains a challenge for multiple facets of modern life. While antibiotics are a primary tool for bacterial control, their overuse has accelerated the appearance of multidrug-resistant bacteria and raises global health concerns. In swine, semen is stored at 17 °C in extenders that contain antibiotics to prevent bacterial growth. Apart from the potential consequences for the female, the proliferation of bacteria in liquid-stored semen is associated with a decline in sperm quality, ultimately reducing farrowing rates and litter sizes. With the aim of reducing the use of antibiotics while keeping bacterial growth under control, we herein investigated whether metal ions could exert an antimicrobial effect without impairing sperm quality. Separate metal ions (Ag, silver sulfadiazine; Al, aluminum chloride; Zn, zinc chloride; and Cu, and cooper chloride) were added at different concentrations (100 μM, 300 μM, 500 μM, 1 mM, and 10 mM) to seminal doses, which were stored at 17 °C for 48 h. Motility, viability, and the intracellular levels of reactive oxygen species (ROS) were tested to determine their effects on sperm quality maintenance. In addition, ions were added to bacterial strains and to extended seminal samples to assess the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Results showed that, although silver sulfadiazine exerted an antimicrobial effect at all the concentrations tested, it also affected sperm quality negatively (p < 0.05). In contrast, aluminum chloride did not impair sperm quality but failed to inhibit bacterial growth at any of the tested concentrations (p > 0.05). Finally, 1 mM concentrations of copper and zinc chloride reduced microbial growth (p < 0.05) without affecting sperm quality. In spite of this, the inhibition of bacterial growth was not complete, thus suggesting that these two ions could contribute to reducing bacterial growth but should be combined with other strategies, such as a lower storage temperature and a decreased concentration of antibiotics. Further research is warranted to address whether copper and zinc chloride could have a synergistic effect when added together. Full article

The anti-aging gene/protein Klotho (Kl), most present in kidneys, has been well studied in mice (mKl), but not in rats (rKl). This study investigated the renal rKl expression in male and female rats. Sex-related measurement of rKl-controlled electrolytes was performed in plasma/urine samples, as were tests on species differences in renal Kl expression (rats vs. mice). rKl mRNA/protein expression was studied by qRT-PCR/Western-blotting in renal total RNA/cell membranes and its localization by immunofluorescence microscopy. Urine/plasma ions (phosphate/total calcium) and macroelements (phosphorus/calcium) were measured biochemically and by ICP-MS, respectively. In rat kidneys, the rKl mRNA/protein was detected in the cortex, outer and inner stripe but not in the papilla, and was immunolocalized in the basolateral membrane of proximal tubules in the cortex and outer stripe, but not in the intercalating cells of the cortical distal tubules, whereas mKl was observed in the mouse kidney cortex but not the outer stripe. Female-dominant expression of renal rKl, affected by androgen’s inhibitory effect, may have contributed to the sex-related level of urine electrolytes, particularly phosphates. Renal mKl expression was male-dominant. Sex- and species-related differences in renal Kl expression may be relevant for the selection of the sex and/or the model organism in studies addressing aging/mineral homeostasis. Full article

Emerging antimicrobial resistance (AMR) in companion animals represents a global health concern as they serve as potential reservoirs for multidrug-resistant (MDR) bacteria, which can be transmitted to humans. Herein, we provide comprehensive surveillance data on resistance patterns in veterinary hospital settings, focusing on urinary tract infection. A total of 23 bacterial strains were isolated from urine specimens of hospitalized companion animals suspected of urinary tract infections (UTIs) between 2022 and 2024. 16S rRNA sequencing analysis revealed that Escherichia coli (47.8%), Klebsiella pneumoniae (21.7%), and Pseudomonas aeruginosa (8.7%) were predominant uropathogens. Minimum inhibitory concentration and minimum bactericidal concentration tests were employed to analyze AMR patterns across different classes of antibiotics. Moreover, antimicrobial susceptibility test exhibited 73.91% MDR according to the standard definition given by the Clinical and Laboratory Standards Institute (CLSI) M100 guidelines. Most Gram-negative bacteria have been shown to be resistant to beta-lactam antibiotics, especially carbapenems. Notably, an E. coli strain was confirmed to possess the bla_NDM-1 gene encoding the carbapenemase New Delhi metallo-β-lactamase. These findings support the implementation of targeted infection control measures and evidence-based treatment protocols to preserve antimicrobial efficacy in companion animal medicine to minimize potential public health risks through the One Health approach. Full article

The agar diffusion method was used to test the antibacterial activity of 12 plant species against Agrobacterium tumefaciens, the bacterium that is responsible for crown gall disease. Leaf, root, or flower extracts were prepared, but not all parts were used for each of the 12 plants listed. Plant extracts from leaves exhibited higher antibacterial activity than those from flowers and roots. Furthermore, the type of solvent had a significant influence on both the antibacterial activity and the flavonoid and polyphenol content. Acetone and alcohol extracts contained higher contents of these compounds than water extracts. The strongest bacteriostatic effect was of the leaf extracts of eucalyptus (Eucalyptus nicholii L.) and St. John’s wort (Hypericum perforatum L.). Based on HPTLC analysis, eucalyptus extracts contained, among others, chlorogenic acid, hyperoside, and quercetin, while St. John’s wort extracts contained rutin, hyperoside, and quercetin. The tansy leaf extracts (Tanacetum vulgare L.) were also rich in flavonoids and phenolic acids, such as kaempferol-3-glucoside, luteolin, chlorogenic acid, cynarine, and rutin. However, a moderate inhibitory effect against the tested bacterium was found in tansy extracts, as well as hop (Humulus lupulus L.), wormwood (Artemisia absinthium L.), peppermint (Mentha piperita L.), yarrow (Achillea millefolium L.), and nettle (Urtica dioica L.) extracts. The least effective were the root extracts of dandelion (Taraxacum officinale F.H. Wiggers coll.) and valerian (Valeriana officinalis L.), as well as the flower extracts of chamomile (Matricaria chamomilla L.) and marigold (Calendula officinalis L.). Given the lack of effective chemical products and the unavailability of commercially resistant cultivars, the use of plant-based extracts for protecting against crown gall appears to be of particular interest. The preliminary results are promising and suggest that eucalyptus and St. John’s wort extracts are the most promising for controlling A. tumefaciens. Full article

Background/Objectives: Oral hygiene is crucial for maintaining overall health, as poor oral care can lead to various systemic diseases. Although xylitol is widely used to inhibit plaque formation, more effective agents are needed to control oral biofilms. Herein, we evaluated the inhibitory effects of sialyllactose (SL), a type of human milk oligosaccharide (HMO), and its partial structure N-acetylneuraminic acid (Neu5Ac) against Streptococcus biofilm. Methods: Under a CO₂ atmosphere, Streptococcus mutans and mixed Streptococcus species were each cultivated in vitro, and the inhibitory effects of HMOs [2′-fucosyllactose, 3′-sialyllactose (3′-SL) and 6′-sialyllactose (6′-SL)] and Neu5Ac on biofilm formation were evaluated. Bacterial biofilm formation was quantified using the crystal violet assay. Biofilm architecture and viability were visualized using confocal laser-scanning microscopy (CLSM) with SYTO9/propidium iodide staining. Transcriptomic responses of S. mutans biofilms to the test compounds were analyzed by RNA-Seq. Statistical analysis was performed using one-way analysis of variance followed by Tukey’s test. Results: SLs and Neu5Ac at 100 mM significantly inhibited S. mutans biofilm formation, with stronger effects than those of xylitol. The inhibitory effects varied among HMOs, with 6′-SL being more effective than 3′-SL and Neu5Ac being most effective. These effects were consistent in assays targeting biofilms formed by other S. mutans strains and in a mixed biofilm comprising Streptococcus species. Gene expression analysis suggested that the inhibitory mechanism involves the physical inhibition of surface adhesion and stress-induced regulation of gene expression. Conclusions: This study provides insights into the physiological significance of HMOs in the oral cavities of humans. HMOs exhibited potential as functional foods to control oral biofilm formation and reduce the risk of oral and systemic diseases. Full article

Citrus bacterial canker (CBC), caused by Xanthomonas citri subsp. citri (Xcc), threatens citrus production worldwide. Long-term dependence on copper-based bactericides not only poses environmental risks but also accelerates the emergence of copper-resistant Xcc strains. To develop safe and efficient alternative control strategies, 72 bacterial strains were isolated from the phyllosphere of citrus plants naturally infected by CBC and identified by 16S rRNA sequencing. Using an Xcc-GFP-based screening method, we systematically screened a highly effective strain, which was identified as Bacillus velezensis RF2 (Bv-RF2). Both inhibition zone assays and bioactivity tests of the crude methanolic extract of Bv-RF2 demonstrated stable antibacterial activity under UV irradiation, protease treatment, high temperature, and across a wide pH range. Whole-genome sequencing and antiSMASH analysis revealed multiple predicted NRPS/PKS-type biosynthetic gene clusters (BGCs). Together with metabolomic profiling, these data provide hypotheses for candidate metabolites that may contribute to antagonism. Bv-RF2 was associated with the induction of PR gene expression in immune-related pathways implicated in CBC responses. In sweet orange leaves, Bv-RF2 infiltration was associated with transient induction of defense-related (PR) genes, consistent with an ISR-like, priming-related response. In addition, Bv-RF2 inhibited the growth of fungal pathogens associated with citrus anthracnose and brown spot in vitro, indicating broad inhibitory potential under the tested conditions. Collectively, Bv-RF2 represents a promising candidate for developing environmentally friendly strategies against CBC and other citrus diseases. Full article