Search Results (473)

Background/Objectives: Fungal colonization and biofilm formation on intrauterine device (IUD) strings are known to contribute to recurrent infections and decreased contraceptive efficacy. This study aims to develop a novel approach to prevent Candida reservoir and biofilm formation on IUD strings, thereby lowering the risk of IUD-associated vulvovaginal candidiasis (VVC). Methods: Cervicovaginal samples were collected from human cervix using a sterile cytobrush, avoiding microbial contamination. Cytological examination using the Papanicolaou method was performed to detect the presence of Candida. The antifungal effect of the essential oils (EOs) was determined by broth dilution and disk diffusion methods. Antifungal and biofilm inhibitory effects of Thymus zygis (Tz) EO-coated IUD strings were determined by agar diffusion and crystal violet binding assays, while fungal growth on the coated strings was assessed using Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray (EDX) analysis. Results: Tz EO exhibited significantly lower minimum inhibitory concentration (MIC ≤ 0.06 µL/mL) and minimum fungicidal concentration (MFC = 0.24 µL/mL) values compared to Melaleuca alternifolia (Ma) EO (MIC > 0.24 µL/mL, MFC = 1.95 µL/mL), along with larger zones of inhibition (ZOI) against both Candida albicans (110.0 ± 6.0 mm vs. 91.3 ± 7.0 mm) and Candida glabrata (84.0 ± 13.1 mm vs. 50.0 ± 9.2 mm), indicating a stronger antifungal potential. On IUD strings coated with 4% (40 μL/g) Tz EO in hypromellose ointment, the biofilm formation of both C. albicans and C. glabrata strains was inhibited by 58.9% and 66.7%, respectively, as confirmed by SEM and EDX. Conclusions: Tz EO-coated IUD strings effectively inhibit Candida growth, suggesting a promising natural strategy to reduce recurrent IUD-associated fungal infections. However, before these results can be translated to clinical practice, additional research is needed. Future investigations may encompass an extended number of Candida isolates, stability and release studies of the EO in relation to the formulation, toxicity to vaginal mucosa, epithelial cells and sperm motility, and the effect on vaginal microbiotia. Full article

In order to develop a new environmentally friendly microbial herbicide for the field of weed control, this study used the metabolite butyl hydroxybenzoate (BP) of the HY-02 strain of Alternaria as the research object. The BP emulsion formula was determined to be a mixture of BP, methanol, and Tween-20 in a ratio of 1:1:2 g/mL. The seed germination inhibition effect, the phytotoxicity of living plants, crop safety, and the field effect of the emulsion were studied. Research has found that adding 0.75% BP emulsion to the seed culture medium inhibits the germination of weed seeds such as Amaranthus retroflexus L., Malva verticillata L. var., and Chenopodium album L. While Brassica campestris L. seeds were unaffected, Triticum aestivum L and Hordeum vulgare L. stem and leaf growth were inhibited. Cucumis sativus L., Lactuca sativa L. var. asparagina, Spinacia oleracea L., and Capsicum annuum L. seeds are significantly inhibited, with germination rates below 20%. We sprayed 0.75% BP emulsion onto live potted plants; among the weeds, the incidence of Amaranthus retroflexus L., Lepyrodiclis holosteoides, Thlaspi arvense L, Galium spurium L., Malva verticillata L. var. Crispa, Chenopodium album L., and Avena fatua L reached 100%. The Pisum sativum L. and Triticum aestivum L. crops were not affected (NS), and they had slight plant height inhibition and slight susceptibility (LS) to highland Hordeum vulgare L. and peppers. They were highly phytotoxicity to Cucumis sativus L. and Spinacia oleracea L. Some plant leaves became infected and died, with incidences of 85% and 82%, respectively. The field experiment showed that after diluting the BP emulsifiable concentrate, the seedling stage spray was inoculated into the Triticum aestivum L. field, and it was found that the BP emulsifiable concentrate at the concentration of 1.00%~0.75% had a herbicidal effect on weeds such as Chenopodium album L., Elsholtzia densa Benth, and Amaranthus retroflexus L. in the Triticum aestivum L. field, and it was safe for Triticum aestivum L. crops in the field. These results indicate that BP emulsion could be developed into a new environmentally friendly microbial herbicide for field application in grass (Triticum aestivum L. and Hordeum vulgare L.) crops. At the same time, BP’s excellent antibacterial, low-toxicity, hydrolysis, and other effects can promote diversification in herbicide development. Full article

The increasing environmental presence of metal oxide nanoparticles (NMOPs) raises concerns regarding their influence on biological wastewater treatment. This study comparatively evaluates the structural and biological effects of zinc oxide (ZnO-NPs) and titanium dioxide (TiO₂-NPs) nanoparticles on activated sludge from a wastewater treatment plant. Experimental exposure covered nanoparticle concentrations of 0.05–0.3 g/L and contact times up to 180 min, with analysis of enzymatic activity (dehydrogenase activity, TTC-SA method), sludge settleability, and particle size distribution. Inhibition of microbial metabolic activity was observed in a clear dose- and time-dependent manner, with ZnO-NPs showing stronger toxicity than TiO₂-NPs. At the highest dose (0.3 g/L), enzymatic activity nearly disappeared after 90 min (0.04 µg TPF/mg MLSS). Both nanoparticles caused floc fragmentation, decreased sludge volume index (SVI), and increased the proportion of ultrafine particles (<0.3 µm). ZnO-NPs induced more severe destabilization, while TiO₂-NPs showed partial re-aggregation of suspended particles at higher concentrations. Additionally, particle size distribution in the supernatant was analyzed, revealing distinct aggregation and fragmentation patterns for ZnO- and TiO₂-NPs. These structural and functional alterations suggest potential risks for treatment efficiency, including reduced nutrient removal and impaired sludge settleability. The study provides a comparative contribution to understanding toxicity mechanisms of ZnO- and TiO₂-NPs and emphasizes the need to monitor NMOPs in wastewater and to develop mitigation strategies to ensure stable plant operation Full article

Keratinous wastes, generated from various industries such as poultry processing, slaughterhouses, and salons, accumulate in the environment due to their slow degradation caused by high disulfide cysteine bonds. Traditional methods of managing these wastes, including incineration, composting, open-air burning, and landfilling, have several disadvantages, such as environmental pollution, release of toxic compounds, and breeding of pathogenic and multidrug-resistant microorganisms. Microbial keratinases, produced by bacteria, fungi, and actinomycetes, offer an eco-friendly alternative for valorizing keratinous waste into valuable peptides and amino acids. The biodegradation of keratinous biomass involves four sequential steps: adhesion, colonization, production of keratinolytic enzymes, and breakdown of the keratin substrate. Optimization of culture conditions, such as pH, temperature, substrate concentration, and metal ions, can enhance keratinase production for industrial applications. Keratinases have multifaceted applications in various sectors, including cosmetics, organic fertilizers, leather treatment, animal feed, detergents, and pharmaceuticals. This review highlights the need to explore keratinolytic strains further and improve keratinase yields to develop sustainable solutions for keratinous waste management and generate value-added products, promoting a circular economy. The techno-economic considerations and current limitations in industrial-scale keratinase production are also discussed, emphasizing the importance of future research in this field. Full article

With the increasing severity of cadmium (Cd) contamination in soil and its persistent toxicity, developing efficient remediation methods has become a critical necessity. In this study, sodium borohydride (NaBH₄) and tea polyphenols (TP) were employed as reducing agents to synthesize biochar (BC)-supported nanoscale zero-valent iron (nZVI), denoted as BH₄-nZVI/BC and TP-nZVI/BC, respectively. The effects of dosage, pH, and reaction time on Cd immobilization efficiency were systematically investigated. Both composites effectively stabilized Cd, significantly reducing its mobility and toxicity. Toxicity Characteristic Leaching Procedure (TCLP) results showed that Cd leaching concentrations decreased to 8.23 mg/L for BH₄-nZVI/BC and 4.65 mg/L for TP-nZVI/BC, corresponding to performance improvements of 29.9% and 60.5%. The immobilization process was attributed to the reduction of Cd(II) into less toxic species, together with adsorption and complexation with oxygen-containing groups (-OH, -COOH, phenolic) on biochar. TP-nZVI/BC exhibited superior long-term stability, while maintaining slightly lower efficiency than BH₄-nZVI/BC under certain conditions. Microbial community analysis revealed minimal ecological disturbance, and TP-nZVI/BC even promoted microbial diversity recovery. Mechanistic analyses further indicated that tea polyphenols formed a protective layer on nZVI, which inhibited particle agglomeration and oxidation, reduced the formation of iron oxides, preserved Fe⁰ activity, and enhanced microbial compatibility. In addition, the hydroxyl and phenolic groups of tea polyphenols contributed directly to Cd(II) complexation, reinforcing long-term immobilization. Therefore, TP-nZVI/BC is demonstrated to be an efficient, sustainable, and environmentally friendly amendment for Cd-contaminated soil remediation, combining effective immobilization with advantages in stability, ecological compatibility, and long-term effectiveness. Full article

Saline–alkali soils in southern Xinjiang present significant challenges for sustainable jujube cultivation, necessitating innovative fertilization strategies to improve soil health and enhance fruit quality. This study investigated the synergistic effects of biochar–nitrogen (N) co-application on soil amelioration and the improvement of jujube quality in saline–alkali jujube orchards. A field experiment was conducted using different biochar application rates (0, BC1, BC2) combined with various N fertilizer types (conventional nitrogen N1, N2, UI-N (urease inhibitor), and NI-N (nitrification inhibitor)), which systematically analyzed soil physicochemical properties, nutrient dynamics, enzyme activities, microbial community structure, and jujube fruit yield and quality parameters. The BC1 biochar application rate emerged as the optimal threshold for soil carbon and N sequestration, with BC1 + N2 treatment achieving the highest total carbon and total nitrogen concentrations, representing increases of 12.4% and 21.42%, respectively, compared to controls. Biochar–N co-application significantly enhanced soil available nutrients, with BC1 + UI-N treatment producing the greatest soil organic matter increase within the BC1 group (9.20–14.51% enhancement). Notably, the treatments modulated soil microelement profiles, suppressing potentially toxic Cu and Mn while enhancing the availability of beneficial Mg and Fe. Soil enzyme activities responded differently, with urease and sucrase activities reaching maximum levels under BC2 + N1 and BC1 + UI-N treatments, respectively. Microbial community analysis revealed that biochar–N combinations significantly restructured both bacterial and fungal communities, with BC1 + NI-N treatment demonstrating superior bacterial α-diversity across all indices. Soil enzyme activities exhibited distinct response patterns, with urease and sucrase activities reaching their peak under the BC2 + N1 and BC1 + UI-N treatments, respectively. Moreover, the co-application of biochar (BC1) with N fertilizer significantly improved fruit performance, increasing per-tree yield by 24.23% and fruit vitamin C content by 16.47%, compared to the control. This study demonstrates that moderate biochar application (BC1) combined with urease inhibitor- enhanced N fertilizer (UI-N) represents an optimal fertilization strategy for saline–alkali jujube orchards, achieving simultaneous soil amelioration and fruit quality enhancement through coordinated regulation of soil–microbe–plant interactions. The established quantitative relationships provide a scientific foundation for the implementation of precision agriculture in arid saline–alkali regions, offering significant implications for sustainable specialty fruit production and soil health restoration in environmentally challenged agricultural systems. Full article

The use of antibiotics in aquaculture is associated with significant environmental risks, including ecosystem disruption and the accumulation of antibiotics in reservoirs and soil cover, as well as the spread of antibiotic-resistant strains, which encourages the search for sustainable alternatives, such as probiotics. This review summarizes the research results on the use of probiotics in aquaculture systems. Special attention is paid to the action mechanisms and diverse effects on the health of aquatic animals, water quality and, most importantly, on the properties of soil in ponds. The research results show that certain strains of probiotics, in particular Bacillus spp., effectively decompose organic substances in sediments, reduce toxic metabolites’ concentration (ammonia, nitrites, hydrogen sulfide), stabilize soil structure, improve aeration and regulate sediments’ pH level and microbial diversity. However, the efficacy in field conditions can vary. Probiotics represent a science-based strategy to reduce dependence on antibiotics, increase system resilience by improving soil and water conditions, and increase productivity. In order to achieve maximum results, it is necessary to optimize the application methods, whilst taking into account local environmental factors. Full article

This study discussed the influence of acetate and sodium chloride concentration on monitoring 2,4-dichlorophenol(2,4-DCP) by electroactive bacteria. The performance of the reactor was represented by power density, and the electrochemical activity was represented by redox capacity. At the same time, micro-electrodes were used to detect the redox potential between biofilms, and the changes in extracellular polymers and microbial community structure under different conditions were also explored. With acetate concentration of 1 g/L and sodium chloride concentration of 0.0125 g/L, the electroactive microorganisms were more sensitive to toxic substances and responded fast. The biofilm also evenly covered on the surface of the carrier, which aided in the diffusion of substances. Although the maximum power density monotonically increased with acetate concentration, high concentration of substrate may mask the inhibitory effect and affect the judgment of inhibitory results. The content of protein and polysaccharide increased monotonically with sodium chloride concentration. However, more polysaccharides would lead to high resistance to electron transfer. Compared to sodium chloride, the microbial content was more affected by acetate. The electroactive microorganisms had strong adaptability to salinity. In practical application, it is conducive to increase the sensitivity of MFCs to reasonably reduce the concentration of acetic acid and sodium chloride. Full article

Cyanobacterial blooms are increasingly becoming more intense and frequent, posing a public health threat globally. Drinking water treatment plants that rely on algal bloom-affected waters may create waste (water treatment residuals, WTRs) that concentrates contaminants. Source waters may contain harmful cyanobacteria, cyanophages (bacteriophages that infect cyanobacteria), and bacteria. Cyanophages are known to affect bloom formation and growth dynamics, so there is a need to understand viral-host dynamics between phage and bacteria in these ecosystems for managing cyanobacteria. This study isolated and characterized lytic cyanophages from WTRs of a HAB-affected lake in Ohio that infect toxic bloom-forming filamentous cyanobacteria Planktothrix agardhii. Phage infections in the Lake Erie cyanobacteria culture were examined visually and via microscopy and fluorometry. Whole genome sequencing and metagenomic analyses were also conducted. Observed changes in Planktothrix included sheared and shriveled filaments, reduced clumping, and buoyancy changes. Photosynthetic pigmentation was unexpectedly more apparent during phage infection. Metagenomic analyses identified nineteen phages and seven other co-existing bacterial genera. Annotated bacterial genomes contained metabolic pathways that may influence phage infection efficiency. Viral genomes were successfully tied to microbial hosts, and annotations identified important viral infection proteins. This study examines cyanobacterial-phage interactions that may have potential for bioremedial applications. Full article

Plant Parasitic Nematodes (PPNs), such as Meloidogyne incognita, cause significant agricultural losses worldwide. Conventional nematicides like methyl bromide are being phased out due to environmental and health concerns, prompting the search for safer alternatives. In previous studies, chalcones 17, 25, and 30, flavonoid compounds, were shown to effectively kill the model nematode Caenorhabditis elegans at concentrations of 10⁻⁴ M. However, the potential of these chalcones to act synergistically at lower concentrations has not been explored. In this study, the nematicidal efficacy of chalcones 17, 25, and 30 was evaluated individually and in combination at concentrations as low as 10⁻⁶ M. The results demonstrate a strong synergistic effect, with combinations achieving 90–100% mortality in C. elegans within 3 days. Additionally, the combination index method revealed significant toxic effects against M. incognita with chalcones 17 and 30 in binary and ternary combinations. To assess the effects of these chalcones on nontarget organisms, chalcones were also tested for antimicrobial activity against soil bacteria; analysis of soil microbiota using 16S rRNA sequencing indicated that chalcones did not significantly disrupt microbial populations. Furthermore, tests on human pluripotent stem cells (hPSCs) reveal no major effects on the viability of these cells at concentrations as high as the concentrations needed to kill nematodes. These findings highlight the potential of chalcones 17, 25, and 30 for effective nematode control without harming soil bacteria or human cells. Full article

MPs are pervasive pollutants in marine ecosystems, posing risks to aquatic organisms due to their small size and bioaccumulation potential. This study investigated the intestinal toxicity of MP particles extracted from mangrove sediments in zebrafish, comparing the effects before and after microbial degradation. Zebrafish were exposed to either undegraded MPs or microbially degraded MP extracts at concentrations of 0 (control), 2, 10, and 50 mg/L for 21 days in 10 L tanks (stocking density: 10 fish/L), with three replicate tanks per concentration. MPs were dispersed ultrasonically before addition to the water. Intestinal samples were collected on 7, 14, and 21 days for the analysis of immune response (tumor necrosis factor-alpha, TNF-α; interleukin-1 beta, IL-1β; interleukin-6, IL-6; interleukin-8, IL-8) and antioxidant activity (superoxide dismutase, SOD; catalase, CAT). Histopathological analysis revealed intestinal wall thinning, villus damage, and epithelial cell detachment in zebrafish exposed to both undegraded and degraded MP extracts; however, undegraded MPs induced more severe intestinal damage. Results indicated dynamic changes in cytokine expression: TNF-α decreased initially before increasing, while IL-1β and IL-8 first rose then declined. IL-6 peaked on day 7, dropped by day 14, and increased again on day 21. CAT expression decreased, whereas SOD increased only in the pre-degradation group. Microbial degradation reduced intestinal damage severity, with effects intensifying at higher MP exposure levels. These findings demonstrate that MPs can impair zebrafish digestive systems, but microbial degradation mitigates their toxicity. This study underscores the importance of biodegradation as a potential environmental remediation strategy and provides experimental evidence on MPs’ impact on aquatic organisms. Full article

Background: Prosthetic candidiasis remains a significant clinical challenge, particularly due to the ability of Candida species to form resilient biofilms on dental prostheses, which limits the efficacy of conventional antifungal treatments. In this context, developing strategies to prevent or reduce biofilm formation is essential. Objectives This study investigates the antifungal and antibiofilm potential of a hydrogel formulation incorporating aminochalcone AM-35 as a candidate for the prevention and treatment of prosthetic candidiasis. Methods: To achieve this, experiments were conducted to determine the minimum inhibitory concentration (MIC) of aminochalcone AM-35 against Candida albicans and Candida tropicalis strains. AM-35 was incorporated into a hydrogel, which was subsequently tested on biofilms formed by these yeast species, both individually and in combination. The experimental disks were sterilized and incubated with C. albicans, C. tropicalis, and a mixture of both strains for 120 h to allow biofilm maturation. After contamination, the samples were divided into four experimental groups: Group 1: Hydrogel; Group 2: Hydrogel+AM-35; Group 3: Sodium hypochlorite (positive control); and Group 4: No treatment. The samples were then subjected to a sonication process to disaggregate the cells, which were then cultured on plates for colony-forming unit (CFU/mL) counts. The hydrogel’s toxicity was evaluated in vivo using the Galleria mellonella model. Results: The hydrogel formulation demonstrated significant antimicrobial activity, with an MIC of 7.8 μg/mL for C. albicans and 3.9 μg/mL for C. tropicalis. Treatment with the hydrogel at a concentration of 39 μg/mL resulted in a significant reduction in the formation and viability of mixed-species biofilms (p < 0.05). Additionally, the results indicated robust activity against C. albicans and C. tropicalis without presenting toxicity in the Galleria mellonella model. In conclusion, the hydrogel formulation exhibited effective antibiofilm activity, significantly reducing the microbial load. Conclusions: These findings open new possibilities for the development of alternative treatments for prosthetic candidiasis. The research suggests that the use of chalcone-based compounds may represent a promising approach in combating fungal infections in dentistry. Full article

Despite significant medical advancements, two major health challenges persist: antibiotic resistance in microbial pathogens and drug resistance in cancer cells. To address these issues, research has increasingly focused on discovering novel natural compounds with dual antimicrobial and anticancer activities. Among such candidates, antimicrobial peptides (AMPs) have attracted attention due to their ability to selectively target microbial and cancer cells while exhibiting minimal toxicity toward normal cells. Although Vietnam possesses rich biodiversity, including a wide range of Anura species, studies on AMPs from these organisms remain limited. In this study, a novel AMP, brevinin-1 E8.13, was identified from the skin secretion of Sylvirana guentheri, a frog species native to Vietnam. The brevinin-1 E8.13 peptide was successfully cloned, sequenced, and chemically synthesized. Functional assays revealed that brevinin-1 E8.13 possesses strong antibacterial activity against Staphylococcus aureus and exerts significant antiproliferative effects on various human cancer cell lines, including A549 (lung), AGS (gastric), Jurkat (leukemia), HCT116 (colorectal), HL60 (leukemia), and HepG2 (liver). The peptide demonstrated moderate to potent cytotoxic activity, with IC₅₀ values ranging from 7.5 to 14.8 μM, depending on the cell type. Notably, brevinin-1 E8.13 exhibited low cytotoxicity toward normal human dermal fibroblast (HDF) cells and even promoted cell proliferation at lower concentrations. Furthermore, Chemically Activated Fluorescent Expression (CAFLUX) bioassay results confirmed that the peptide significantly downregulated Cyp1a1 gene expression in HepG2 cells. Collectively, these findings highlight the therapeutic potential of brevinin-1 E8.13 as a dual-function antimicrobial and anticancer agent derived from the skin secretion of Sylvirana guentheri. Full article

The excessive use of conventional fertilizers has led to low nutrient-use efficiency and significant environmental challenges. To address these limitations, this study aimed to evaluate the effects of Fe₂O₃ and CuO nanoparticles (NPs) as potential nanofertilizers, on the soil chemical composition, nutrient fractionation, enzyme activity, and Lepidium sativum L. growth. The results of the study showed that Fe₂O₃-NPs improved nitrogen bioavailability and enhanced plant biomass, particularly at low to moderate doses. CuO-NPs, in contrast, reduced nitrogen and phosphorus mobility and showed phytotoxic effects at high concentrations. Enzyme activity was suppressed at high NP levels, likely due to oxidative stress. Nutrient fractionation revealed the increased immobilization of phosphorus and the moderate mobilization of potassium and copper, depending on NP type. Based on the results, Fe₂O₃-NPs show potential as a nanofertilizer for enhancing soil fertility and plant growth in sandy loam soils, whereas CuO-NPs require caution due to toxicity risks. Future research should focus on long-term environmental impact, optimal NP concentrations, and their interaction with soil microbial communities. Full article

Background/Objectives: Infectious endophthalmitis is a vision-threatening complication of intraocular surgery and intravitreal injections. Standard treatment involves intravitreal antibiotics; however, concerns regarding multidrug resistance and vancomycin-associated hemorrhagic occlusive retinal vasculitis (HORV) highlight the need for alternative antimicrobial strategies. This study aimed to evaluate the clinical efficacy and safety of a protocol combining intravitreal injection of 1.25% povidone-iodine (PI) with intraoperative irrigation using low concentrations of vancomycin and ceftazidime. Methods: We retrospectively analyzed 11 eyes from patients diagnosed with postoperative or injection-related endophthalmitis. Six of the eleven cases received an initial intravitreal injection of 1.25% PI, followed by pars plana vitrectomy with irrigation using balanced salt solution PLUS containing vancomycin (20 μg/mL) and ceftazidime (40 μg/mL). A second intravitreal PI injection was administered at the end of surgery in all cases. Additional PI injections were administered postoperatively based on clinical response. Clinical outcomes included best-corrected visual acuity (BCVA), microbial culture results, corneal endothelial cell density, and visual field testing. Results: All eyes achieved complete infection resolution without recurrence. The mean BCVA improved significantly from 2.18 logMAR at baseline to 0.296 logMAR at final follow-up (p < 0.001). No adverse events were observed on specular microscopy or visual field assessment. The protocol was well tolerated, and repeated PI injections showed no signs of ocular toxicity. Conclusions: This combination protocol provides a safe and effective treatment strategy for infectious endophthalmitis. It enables rapid and complete infection resolution while minimizing the risks associated with intravitreal antibiotics. These findings support further investigation of this protocol as a practical and globally accessible alternative to standard intravitreal antimicrobial therapy. Full article