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Botrytis cinerea is a globally distributed phytopathogenic fungus that causes gray mold in eucalyptus seedlings, posing a severe threat to eucalyptus nursery production. Pseudomonas eucalypticola Liu et al. NP-1 is an endophytic bacterium isolated from eucalyptus with broad-spectrum antifungal activity. In this study, the fermentation broth extract of strain NP-1 was prepared using the organic solvent extraction method. The inhibitory effects, antifungal mechanisms, and biocontrol efficacy of the extract against B. cinerea were investigated. The results suggested that the NP-1 extract effectively inhibited mycelial growth, conidial germination, and germ tube development of B. cinerea. The EC₅₀ and EC₉₀ values for mycelial inhibition were 110 μg/mL and 332 μg/mL, respectively, while those for conidial germination inhibition were 126 μg/mL and 310 μg/mL. Microscopic and ultramicroscopic observations indicated that while the mycelial structures in the control and EC₅₀ groups remained intact, the EC₉₀ treatment significantly was associated with protoplasmic aggregation, leakage, and cavitation, suggesting potential structural damage to the fungal cells. In vitro and in vivo biocontrol assays showed that the control efficacy against gray mold reached 90.0% on detached eucalyptus leaves and 93.3% on eucalyptus seedlings. These findings elucidate the biocontrol potential of NP-1 and lay a foundation for the development of bio-based pesticides. Full article

Volatile organic compounds (VOCs) have garnered substantial research interest in recent years due to their biodegradability, low toxicity, and potent antimicrobial properties against various plant pathogens. As a typical herbivore-induced plant volatile (HIPV) elicited by Nilaparvata lugens (Brown planthopper, BPH), (E)-2-hexenal has been identified as a promising natural antimicrobial agent. In this study, we investigated the protective potential of (E)-2-hexenal against Rhizoctonia solani (R. solani) in rice, focusing on both its direct antifungal activity and host-mediated defense mechanisms. In vitro antifungal assays demonstrated that treatment with 100 μL/mL (E)-2-hexenal resulted in a 91.07% inhibition of R. solani mycelial growth after 48 h. Scanning electron microscopy (SEM) observation and chitinase activity analysis revealed that (E)-2-hexenal suppressed fungal growth by disrupting the structural integrity of the pathogen cell wall. Furthermore, 100 μL/mL (E)-2-hexenal effectively conferred protection to detached rice leaves. Whole-plant inoculation assays confirmed that (E)-2-hexenal pretreatment significantly alleviated disease symptoms and triggered systemic resistance in rice plants. Physiological and biochemical analyses showed that (E)-2-hexenal treatment enhanced the activities of defense-related enzymes, elevated hydrogen peroxide (H₂O₂) levels, and promoted the accumulation of defensive metabolites in rice leaves. HPLC-MS quantification further revealed significant increases in the endogenous levels of jasmonic acid (JA) and salicylic acid (SA). Transcriptomic KEGG pathway enrichment analysis indicated that differentially expressed genes (DEGs) were mainly involved in alpha-linolenic acid metabolism, diterpenoid biosynthesis, phenylpropanoid biosynthesis, plant–pathogen interaction, and plant hormone signal transduction. Collectively, these results suggest that (E)-2-hexenal enhances rice resistance to sheath blight disease via a dual-action mechanism: direct inhibition of fungal development and activation of host immune responses. Our findings highlight the potential application of (E)-2-hexenal and other VOCs in developing eco-friendly strategies for sustainable rice disease management. Full article

This study aimed to separate and characterize compounds from Aspergillus tubingensis ZMGR14. The antifungal activities of monomer compounds and the ethyl acetate (EtOAc) layer from the fermented liquor of A. tubingensis were isolated, purified and structurally identified. The EtOAc layer from the fermented liquor showed significant antifungal activity against Fusarium oxysporum and Alternaria alternata with IC₅₀ values of 273.8 and 330.7 μg·mL⁻¹, respectively. The EtOAc extract was further purified by column chromatography and recrystallization to yield six compounds. Antifungal trials showed that Cyclo-(L-Pro-D-Leu) (5) exhibited the highest inhibition against A. alternata and F. oxysporum, with an IC₅₀ value of 48.1 and 232.7 μM, respectively, and cyclo-(L-Pro-L-Leu) (6) displayed moderate antifungal activity against Alternaria solani, with an IC₅₀ value of 493.4 μM. The results suggest that the EtOAc extract of ZMGR14 and its bioactive compounds hold promise as environmentally friendly microbial fungicides. Full article

Background: Plant essential oils are extensively utilized for their antimicrobial properties; however, the specific antifungal mechanisms of certain compounds are not well characterized. Geraniol, a naturally occurring monoterpene alcohol approved for use in foods, demonstrates potential efficacy against spoilage fungi, yet detailed mechanistic insights are lacking. Methods: In this study, we determined the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of geraniol against P. polonicum. We assessed the underlying mechanisms by evaluating membrane integrity, intracellular leakage, reactive oxygen species (ROS), antioxidant enzymes (superoxide dismutase [SOD], peroxidase [POD], catalase [CAT]), malondialdehyde (MDA) levels, ATP content, and ATPase activity. Inoculated yam slices were exposed to geraniol vapor, and we monitored sensory, physicochemical, enzymatic, and microbial parameters. Results: Geraniol exhibited a minimum inhibitory concentration/minimum fungicidal concentration (MIC/MFC) of 0.3 mL/L. It disrupted cellular membranes, induced leakage, generated ROS, and caused lipid peroxidation, leading to elevated levels of malondialdehyde (MDA). Additionally, geraniol activated antioxidant enzymes and impaired energy metabolism. Fumigation with geraniol dose-dependently delayed the deterioration of yam, reduced weight loss, preserved texture and color, inhibited polyphenol oxidase (PPO) and POD activities, enhanced CAT and SOD activities, lowered MDA levels, and suppressed bacterial growth. Conclusions: Geraniol inhibits P. polonicum through multiple mechanisms, including membrane disruption, oxidative stress, and interference with energy metabolism, thereby effectively preserving the quality of fresh-cut yam and demonstrating potential as a natural preservative. Full article

This study investigates the volatile composition of twelve medicinal plant species belonging to the Lamiaceae family, which are widely recognized for their diverse biological activities, including antioxidant, antibacterial, and antifungal properties. Despite extensive studies on essential oils, comparative analyses using solvent-free techniques under different microclimatic conditions remain limited. This study investigates the volatile compounds in twelve medicinal plants from the Lamiaceae family using headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC-MS). Lamiaceae plants are recognized for their diverse medicinal properties, including antioxidative, antibacterial, and antifungal effects. A total of 74 volatile compounds were identified, encompassing terpenes, alcohols, esters, aldehydes, and ketones. Notably, Lavandula spica L. exhibited the highest number of unique volatiles (28), while Melissa officinalis L. had the fewest (16). Key compounds included Citral (65.48%) in Melissa officinalis L., Menthol (33.37%) and Menthyl acetate (30.53%) in Mentha piperita L., Carvone (45.86%) in Mentha spicata L., and Eucalyptol (54.71%) in Origanum syriacum L. Plants from Adana Botanic Park were rich in terpenes and ketones, whereas those from Osmaniye contained higher levels of alcohols, aldehydes, and esters. The findings emphasize the impact of geographic location on volatile profiles and suggest avenues for further research into medicinal efficacy and optimal dosage. This study supports the sustainable use of plant biodiversity (SDG 15) and highlights the importance of bioactive compounds for human health and well-being (SDG 3). 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

Salinity stress adversely affects plant growth, yield, and productivity. It requires an investigation of ameliorative techniques, for example, spraying synthesized nanoparticles such as zinc oxide nanoparticles (ZnOnps). This current research studied the impact of sodium chloride as a stressor (150 mM NaCl) and the application of ZnOnps (2 g L⁻¹) on some biochemical properties of maize (Zea mays) leaves. The experiment involved examining some mineral concentrations (Na, K, Mg, Zn, Cu, Mn), fatty acid profile, and the antimicrobial (antibacterial and antifungal) properties of aqueous and diethyl ether maize leaf extracts, supported by molecular docking studies of the 17 previously determined phenolic compounds against DNA gyrase and alpha-L-fucosidase enzymes. Applying ZnOnps markedly decreased sodium concentrations from 5.8 to 1.9 mg g⁻¹ dry weight (DW) and established ion balance. ZnOnps also reduced γ-linolenic acid levels to 60% under stress, returning them to normal (34%), while increasing palmitic acid to 30%. Determining the antimicrobial activities indicated that extracts from plants sprayed with ZnOnps exhibited enhanced antimicrobial activity, as evidenced by the lowest minimum inhibitory concentrations against bacterial and fungal strains, including Salmonella typhi and Aspergillus flavus. The computational molecular docking confirmed the antimicrobial findings, with the compound apigenin-7-glucoside, which exhibited the highest binding affinity scores for antibacterial (−7.4 kcal/mol), and the compound chlorogenic acid as antifungal (−7.2 kcal/mol) against the enzyme targets. Thus, ZnOnps can be considered an efficient strategy for mitigating salinity stress in maize plants while elevating the antimicrobial activity and stability of variant secondary compounds. Full article

Chlorine dioxide (ClO₂) is a neutral oxidant molecule with a short lifespan once in contact with electron donors (organic matter). ClO₂ solutions have antiviral, antibacterial, antifungal, anti-protozoan, anti-inflammatory, anticancer, and wound-healing activity and it was used at safe concentrations on patients from different countries during the COVID-19 pandemic. In Mexico, 1067 COVID-19 patients received compassionate treatments with ClO₂ during the 2020/2021 pandemic years. We describe the treatments and clinical reports of these patients, as it concerns the oxygen saturation (SpO₂) recovery, and provide a biochemical explanation. The number of healed patients was 1057, >99% of the total and SpO₂ showed a hyperbolic fast increase. This might happen because ClO₂ attracts one electron from the organic matter and produces a chlorite anion (${\mathrm{ClO}}_2^{-}$). This new molecule is known to exhibit metabolic activity in the blood stream. On the one hand, it will perform the aforementioned antibiotic and healing properties. On the other hand, it will also allow the production of oxygen (O₂) to be transported by the Oxyhemoglobin. This reaction is mediated by an intermediate state of a ferryl molecule (Fe=O) in the allosteric heme site of methemoglobin, which behaves as a reductase enzyme. This reaction can explain the rapid and steady increase in O₂ saturation in healed patients. Full article

Yeasts have attracted increasing attention as potential alternatives to traditional bacterial probiotic strains due to their physiological resilience and functional versatility. However, the probiotic potential of yeast strains associated with Mexican cocoa bean fermentation remains largely unexplored. Therefore, this study aimed to conduct a preliminary screening of physiological and surface-related traits associated with probiotic functionality in four autochthonous Saccharomyces cerevisiae strains (YCTA5, YCTA9, YCTA14, and YCTA16), previously isolated from cocoa fermentation, using Saccharomyces boulardii (Jarrow Formulas^®) as a reference strain. Evaluated parameters included tolerance to temperature, pH, and bile salts; hemolytic activity; survival in vitro under gastrointestinal (GI) conditions; bile salt hydrolase activity; auto-aggregation; co-aggregation; hydrophobicity; and response to antifungal agents (fluconazole, ciclopirox, nystatin, and clotrimazole). All yeast strains grew at 37 °C and at pH 4–8 and showed no hemolytic activity. All strains exhibited high auto-aggregation (>70%) and hydrophobicity values ranging from 55 to 88%. In the coaggregation assay, strains YCTA9, YCTA14, and YCTA16 showed moderate interactions with Escherichia coli, Bacillus cereus, and Listeria innocua, with some combinations exceeding 50%. Nevertheless, none of the yeast strains exhibited measurable growth at pH 2; bile salt tolerance was limited to 0.1% Oxgall, and viability decreased by approximately 54–56% after simulated gastrointestinal transit. These findings indicate that although some strains exhibited promising surface-related properties, significant physiological constraints restrict their probiotic potential under the tested conditions. Therefore, the studied yeast strains should be regarded as preliminary candidates requiring further validation. This work provides a first-stage evaluation for identifying functional yeast strains from Mexican cocoa bean fermentation, serving as a basis for future in vitro and in vivo studies. Full article

Chitosan-based silver nanoparticles (Ch-AgNPs) are emerging as promising antimicrobial materials with potential applications in crop protection. This study evaluated the formulation-dependent antimicrobial activity and plant compatibility of Ch-AgNPs synthesized from chitosan extracted via different routes from shrimp shells. Antibacterial activity was assessed against representative Gram-negative and Gram-positive model bacteria (Escherichia coli and Staphylococcus aureus), as well as phytopathogenic bacteria (Xanthomonas campestris, Pseudomonas syringae), using disk diffusion assays. Antifungal activity was evaluated against Fusarium graminearum in vitro and in a controlled growth chamber. All formulations exhibited concentration-dependent antibacterial activity, with L10 and L20 formulations derived from optimized lactic acid-based extraction routes and DP4 derived from an inorganic deproteinization-based extraction route showing the highest efficacy at 1.0 mg/mL. Strong antifungal activity was observed, particularly for L10 and DP4, achieving mycelial growth inhibition of 92% and 84%, respectively, at 1.0 mg/mL. Seed germination and seedling growth assays confirmed that all formulations were non-phytotoxic at 1.0 mg/mL, with L10 and DP4 significantly enhancing germination parameters and early plant growth. Under controlled conditions, these formulations also reduced the incidence and severity of crown and root rot in spring wheat caused by F. graminearum. These findings demonstrate that optimized Ch-AgNP formulations combine antimicrobial activity with plant compatibility, highlighting their potential for crop protection, pending further environmental safety and agronomic validation under field conditions. Full article

Maize (Zea mays L.) is a significant staple food crop in the developing world. Despite its significance, diseases and pests are limiting its supply. Farmers have primarily relied on synthetic chemicals as control measures; however, these chemicals are harmful to humans, animals, and the environment and exacerbate pest recurrence. Medicinal plants have shown promising potential as alternative pest- and disease-controlling agents, offering an economical, sustainable, biodegradable, and cost-effective approach. This review article synthesises phytochemical, ethnobotanical, and experimental data from relevant peer-reviewed papers published across various years to identify medicinal plants. Thirty-one unique plant families have been identified and have been used to control pests and diseases of maize. Some families represented both antifungal and insecticidal applications. Medicinal plants such as Senna obtusifolia, Euphorbia balsamifera, Aristolochia ringens, Allium sativum, Azadirachta indica, Carica papaya, Moringa oleifera, and Ficus exasperata have shown antifungal and insecticidal properties, primarily under laboratory conditions. Most of the evidence is derived from laboratory studies, with only limited validation in real field conditions and with limited evaluation of safety for non-target organisms. Furthermore, this review highlighted the extraction methods, solvents used, plant parts, major active ingredients, and mode of action. Future prospects for integrating ethnobotanical knowledge with contemporary scientific methods to optimise biopesticide production are also discussed, along with the challenges of standardisation, formulation, and commercialisation. Full article

Acrylic resin is widely used in the fabrication of complete dentures, interacting significantly with the intraoral environment. However, complete dentures face challenges such as stability issues and biofilm accumulation. Glaze application is a common method to reduce surface porosity and microbial adhesion, but it also decreases surface wettability, potentially impairing salivary film formation essential for peripheral sealing. This study aimed to incorporate titanium dioxide and zinc oxide nanoparticles into the glaze applied to thermally activated acrylic resin (TAAR) via spray coating to enhance surface wettability and antifungal activity. Four groups were tested: G (TAAR + commercial glaze − control); AlG (TAAR + commercial glaze + aluminum oxide − roughness control); TiG (TAAR + commercial glaze + titanium dioxide); and ZnG (TAAR + commercial glaze + zinc oxide). Evaluations included flexural strength, color and translucency, surface analysis and antibiofilm activity against Candida albicans. Data were analyzed using one-way ANOVA. No statistically significant differences in mechanical strength (MPa) were observed (G: 108.54 ± 8.36; AlG: 113.60 ± 11.95; ZnG: 111.98 ± 9.27; TiG: 113.66 ± 10.41). Surface roughness significantly increased, and contact angle decreased, indicating improved wettability. Regardless of the antifungal activity no improvement was detected (G: 6.71 ± 0.10; AlG: 6.82 ± 0.08; ZnG: 6.72 ± 0.20; TiG: 6.66 ± 0.18). In conclusion, the incorporation of nanoparticles into the glaze improves the wettability of acrylic resin surfaces, potentially enhancing peripheral sealing and denture retention, which is beneficial for patients with reduced alveolar ridge height. Full article

Candida albicans-associated denture stomatitis is a common inflammatory condition in denture wearers. Conventional tissue conditioners provide temporary relief but lack intrinsic antifungal activity, allowing persistent microbial colonization and biofilm formation. Functionalization with bioactive agents represents a promising preventive strategy. This study evaluated the antifungal efficacy and biocompatibility of pterostilbene (PTE), a natural stilbenoid compound, incorporated into a commercially available tissue conditioner. Antifungal activity of PTE against C. albicans ATCC 10231 was evaluated using broth microdilution and XTT biofilm assays. Tissue conditioner discs containing 1% and 2.5% (w/w) PTE were fabricated and tested after 24 h, 72 h, and 1 week using colony-forming unit (CFU) counts and metabolic activity assays. Biocompatibility was assessed by exposing mouse embryonic fibroblast (MEF) cells to conditioned eluates followed by an MTT viability assay. PTE inhibited biofilm formation in a concentration-dependent manner, with significant suppression observed at ≥8 µg/mL (p < 0.001). A time-dependent antifungal effect was observed over one week. PTE-functionalized tissue conditioners significantly reduced fungal adhesion compared with controls at all-time points (p < 0.001). Cell viability remained above 70%, meeting ISO 10993-5 criteria for non-cytotoxicity, indicating potential for localized prevention of denture stomatitis. Full article

In various areas of human activity, there is a need for new antimicrobial agents that are minimally hazardous to humans and the environment while remaining effective against multidrug-resistant microorganisms. The use of nanomaterials, particularly carbon-based ones, for this purpose is attracting growing interest. This review presents a quantitative analysis, based on published data, of the antibacterial and antifungal activity of various carbon nanomaterials, focusing on fullerenes, nanodiamonds, graphene oxide, carbon nanotubes, and carbon dots. Their antimicrobial activity is compared both among themselves and with other antimicrobial agents; the effects of their physicochemical properties, functionalization, and photodynamic activity on this activity are also examined. Full article

Broccoli (Brassica oleracea var. italica) by-products represent an abundant and underutilized source of bioactive compounds with potential applications in sustainable food systems. This study aimed to characterize the microbiota associated with different plant fractions (leaves, stems, and heads) of broccoli (Parthenon and Tritón cultivars) and to evaluate the antioxidant and antimicrobial properties of their extracts, using cauliflower as a reference. Microbial counts and fungal identification (ITS sequencing) were performed, while phytochemical profiles were analyzed by HPLC-ESI-QTOF. Antioxidant activity was assessed using DPPH and ABTS assays, and antimicrobial activity under in vitro conditions was evaluated against selected foodborne bacteria and phytopathogenic fungi. Broccoli by-products, particularly leaves, showed lower microbial loads in certain cultivars and were rich in phenolic compounds and glucosinolates; however, higher phenolic content did not always correlate with greater antioxidant activity, highlighting the importance of compound composition. All extracts showed strong antibacterial activity at higher concentrations, especially against Listeria spp. Notably, antifungal activity was selective but relevant, with consistent inhibition observed against Alternaria alternata, while Penicillium purpurogenum and Botrytis cinerea exhibited higher resistance. Overall, these findings highlight the potential of broccoli by-products as sustainable sources of natural bioactive compounds for food applications, particularly in the development of preservation strategies and postharvest treatments. Further studies focusing on individual compounds and their specific biological activities are needed to better understand the mechanisms underlying these effects and to support their application in real food systems. Full article