Search Results (64)

At the archeological site of Pompeii, the deterioration of exposed structures is frequently associated with the combined action of microbial colonization and soluble salts, both recognized as major agents of decay affecting ancient surfaces. Although biocides are commonly applied during cleaning procedures to reduce microbial biomass, their incorporation into restoration-oriented formulations for the protection of porous stone substrates requires careful assessment of efficacy, microbiological risks, and sustainability. This study evaluated the performance of 2,4,5,6-tetrachloroisophthalonitrile (chlorothalonil) and iodopropynyl butylcarbamate (IPBC) as candidate active ingredients for conservation applications in activated new mortars. Yellow tuff, gray tuff, and brick samples collected from different sectors of Pompeii were investigated through culture-based analyses, ATP quantification, and metabolic profiling. Biocidal treatments were subsequently tested under laboratory conditions. The investigated substrates exhibited variable microbial counts and metabolic activity, generally reflecting different degrees of deterioration. Chlorothalonil showed negligible inhibitory effects, whereas IPBC reduced fungal growth in a dose-dependent manner. However, the highest IPBC concentration induced a red chromatic alteration associated with the selection of a bacterial strain preliminarily identified as Micrococcus roseus. Phenotype microarray analyses revealed broad chemical tolerance. Overall, biocidal treatments may alter microbial communities, favor tolerant microorganisms, and produce undesirable aesthetic effects. Finally, the study also assessed the environmental impact associated with laboratory and field activities, highlighting potential mitigation strategies to support more sustainable conservation research practices. Full article

The yield loss of tomatoes grown in Punjab is 30–60% due to early blight caused by Alternaria solani during humid monsoons. Five fungicides, namely, Score 250 EC (difenoconazole), Antracol 70 WP (propineb), Topsin-M 70 WP (thiophanate-methyl), Dithane M-45 80 WP (mancozeb), and Kavach 75 WP (chlorothalonil), were evaluated in this laboratory experiment using the poisoned food technique at concentrations of 0.1, 0.2, and 0.3. Score 250 EC showed the highest antifungal activity, resulting in the lowest mean mycelial growth (26.44 mm) and maximum inhibition. All interventions were significantly better than controls (p < 0.01), and the effect became concentration-dependent. Intensive alternation of difenoconazole and Antracol at the IPM levels is an effective way of reducing selection pressure on resistance. Full article

Chlorothalonil is a widely used fungicide in agriculture, but its excessive application can lead to environmental contamination. This study investigated the biodegradation potential of Proteus terrae ZQ02 in free and immobilized forms. Under optimal conditions (37 °C, pH 7), free cells degraded 97.2–98.7% of chlorothalonil (50 mg/L) within seven days. Bacterial microcapsules were prepared using 3% sodium alginate, 2% calcium chloride, and 60 g/L wet biomass, with encapsulation times ranging from 6 to 12 h. The microcapsules displayed uniform size, high mechanical strength, porous structure, and excellent mass transfer, ensuring stable degradation activity. Encapsulated cells demonstrate enhanced tolerance to variations in pH, temperature, and salinity compared to free cells. In soil, microcapsules reduced chlorothalonil half-lives to 1.33–5.45 days for concentrations of 10–30 mg/L, achieving 92–96% degradation over 14–35 days. In tomato-planted soils, encapsulated and free cells degraded 96.3% and 81.6% of residues, respectively, after 28 days, significantly exceeding the control. These findings highlight that immobilization improves the stability, reusability, and efficiency of P. terrae ZQ02, making it a promising strategy for sustainable chlorothalonil biodegradation. The study demonstrates the potential of combining microbial strains with carrier materials for effective pesticide remediation and environmental protection, providing a foundation for large-scale applications in contaminated agroecosystems. Full article

The catalytic mechanism of the Zn(II)-dependent chlorothalonil dehalogenase from Pseudomonas sp. CTN-3 (Chd) was examined using molecular dynamics (MD) simulations, Bayesian network analysis, and Markov state model analysis to quantify its motions. Chd selectively substitutes an aromatic chlorine-carbon bond in chlorothalonil (TPN; 2,4,5,6-tetrachloroisophtalonitrile) with an aromatic alcohol (4-hydroxytrichloro-isophthalonitrile; 4-OH-TPN). It is a homodimer with two solvent-accessible channels in each monomer, which are proposed to provide different routes for substrate and products to access/leave the catalytic Zn(II) site. Based on MD simulations, Chd exhibits allosteric behavior wherein a “Y”-shaped substrate channel exhibits a “flip flop” mechanism, where the “right” substrate channel opens to allow TPN to enter, after which it closes, followed by the “left” channel opening. The “right” channel then reopens, likely to allow the product, 4-OH-TPN, to leave the active site, but this reopening of the right channel drives the “left” channel to close. Coupled with the substrate channels alternately opening and closing, a corresponding possible Cl⁻ channel opens and closes. Although the dynamics of this process are fast, Chd needs to overcome a 5 kT free-energy barrier for this transition and to relax after opening. Additionally, exposed “wing” residues, hydrophilic residues at the ends of protruding α-helices, act as allosteric indicators, signaling the complex allosteric motions required to open the substrate channel. We propose, for the first time, a dynamic mechanism that drives substrate binding and product release, providing new insight into Chd’s catalytic mechanism. Full article

Feed and water scarcity are major challenges for the sustainability of livestock production, particularly in semi-arid regions with structural limitations in resource availability. In this context, the valorization of agro-industrial by-products contributes to circular agriculture, reduces waste, and promotes more efficient resource use, in line with the United Nations Sustainable Development Goals. This study evaluated the inclusion of partial mixed tomato residue (PMR) silage in sheep diets and its effects on productive performance, total water intake, and meat quality. Eighteen ewe lambs were assigned to two groups: control (concentrate and deferred pasture) and PMR (tomato residue silage and deferred pasture). The PMR silage had a pH of 3.97 and was mainly characterized by lactic and acetic acids, with minor amounts of propionic and butyric acids. The butyric acid concentration (8.9 g kg⁻¹ DM) slightly exceeded the recommended threshold (0.5% DM), suggesting some clostridial activity but remaining below levels associated with severe deterioration. Animals fed PMR silage showed a 36% higher dry matter intake (p = 0.001), with greater intake of total digestible nutrients and fiber. This translated into a 54% higher average daily gain (p = 0.02) and an 11% greater final body weight compared with the control group (p = 0.02). Dietary water intake was also higher in the PMR group, reducing direct water consumption from drinkers by 38% (p < 0.001). Meat quality parameters were unaffected by the diet. Pesticide residue screening by LC-MS/MS revealed no detectable levels of abamectin, cymoxanil, chlorothalonil, difenoconazole, or mancozeb in silage. In meat samples, only chlorothalonil was tested and it was not detected. However, the use of PMR silage increased direct energy demand due to transport and compaction, while feeding costs per unit of weight gain were reduced. Overall, PMR silage proved to be a safe, fermentatively stable, and effective feeding alternative that enhances performance, reduces direct water intake, and maintains meat quality, representing a viable strategy for small ruminant production in water-limited regions. Full article

Chronic exposure to pesticides poses significant hepatorenal toxicity risks, yet a systematic comparison of their effects across species and tissues is lacking. In this study, we systematically evaluated the cytotoxicity of eight pesticides using human (CCC-HEL-1 hepatocytes; 293T renal cells) and rodent (IAR hepatocytes; NRK renal cells) cellular models. Our results showed substantial variations in potency, with chlorothalonil exhibiting the highest toxicity (IC50 = 32.55 mg/L in 293T cells) and chlorpyrifos the lowest (IC50 = 444.5 mg/L in 293T cells). Principal component analysis revealed distinct species- and tissue-specific response patterns, highlighting the unique resistance of NRK cells. Mechanistic investigations demonstrated organ-specific biomarker alterations, such as elevated hepatic ALP and suppressed renal KIM-1. Remarkably, the MRP2 transporter exhibited tissue-specific divergence, being significantly downregulated in renal cells (all 8 pesticides, p < 0.005) and most hepatic cells (7/8 pesticides, p < 0.05), while propiconazole uniquely upregulated it in hepatocytes (1.5-fold, p < 0.05). Collectively, these findings offer critical mechanistic insights into pesticide-specific toxicity and cross-species susceptibility, providing valuable data to improve human health risk assessment in food safety and toxicology. Full article

The overuse of pesticides has raised serious food-safety and environmental concerns. Carbon dots (CDs) can act as biostimulants by enhancing photosynthesis, thereby promoting plant growth and stress tolerance. However, their roles in plant pesticide detoxification remain unclear. This study synthesized nitrogen-doped carbon dots (N-CDs) with strong blue fluorescence, excellent biocompatibility, and no cytotoxicity observed in HEK 293T cells. The N-CDs were synthesized from 1.025 g citric acid and 0.379 g urea, producing particles with a size of around 2.42 nm and abundant hydrophilic groups. When applied to tomato plants, N-CDs (especially at 150 mg·L⁻¹) significantly reduced chlorothalonil (CHT) residues affecting tomato, by up to 66%. Importantly, N-CDs also improved tomato plant growth, reversing the negative effects of CHT on key parameters such as height, leaf area, and biomass. Indeed, under CHT conditions, N-CDs significantly reduced the contents of malondialdehyde, superoxide, and hydrogen peroxide. In contrast, N-CDs significantly increased the activities of superoxide dismutase, peroxidases, catalase, and ascorbate peroxidase to 117.57%, 158.53%, 162.79%, and 152.23%, respectively. Notably, N-CDs dramatically changed the glutathione pool for tomato detoxification. Overall, this study synthesized the non-cytotoxic N-CDs that not only promote tomato growth but also alleviate CHT toxicity by strengthening the tomato’s antioxidant defense system. Full article

The continued use of agrochemicals in Valle de Arista, SLP, Mexico, has generated loss of effectiveness of active ingredients and impacts on public health and the environment. To identify environmental and socioeconomic impacts, a quantification method was designed using the Kovach Environmental Impact Quotient and environmental accounting of pesticides (Leach and Mumford) that included agricultural diagnosis and identification of agrochemical impacts. Producers, technical advisors and agrochemicals dealers were surveyed as key agents of tomato (Solanum lycopersicum) and chili pepper crops (Capsicum annuum) due to their economic importance. Gower quotation coefficients were calculated to measure similarity of quantitative, qualitative and dichotomous variables with continuous, discrete and binary characteristics. The use of fungicides (carbendazim and chlorothalonil) showed the greatest environmental impact, followed by insecticides (endosulfan and thiametoxam) and herbicides. The negative externality averaged US$15.60 ha⁻¹ annually, corresponding to 50% of tomato, 31.25% of poblano pepper and 18.75% of serrano pepper. Estimated damages due to the use of greenhouses were 37.7% to the consumer, 21.2% to the worker, 14.8% to aquatic life, 3.6% to birds, 9.2% to bees and 3.3% to insects. Full article

Determining the effectiveness of fungicide programs based on cultivar resistance to pathogens, especially late leaf spot (caused by Nothopassalora personata (Berk. & M.A. Curtis) [U. Braun, C. Nakash., Videira & Crous]) is important in establishing recommendations to peanut (Arachis hypogaea L.) farmers. Research was conducted in North Carolina during 2021 and 2022 at three locations to compare the incidence of late leaf spot (e.g., visual estimates of percent of peanut leaflets with lesions), percentage of the peanut canopy defoliated caused by this disease, and yield of the peanut cultivars Bailey II, Emery, and Sullivan when exposed to five fungicide regimens including a non-treated control. Peanut yield was not affected by the interaction of cultivar × fungicide regimens. While differences in leaf spot incidence and canopy defoliation were noted for cultivars, these differences did not translate into differences in peanut yield. All fungicides regimens protected peanut yield from leaf spot disease regardless of the number of sprays during the cropping cycle (e.g., three, four, or five sprays). Peanut yield in the absence of fungicides was 4410 kg/ha compared with a range of 5000 to 5390 kg/ha when fungicides were applied. Peanut yield was greater when fungicides were applied four or five times compared with only three sprays or non-treated peanut. The regimen with five consecutive sprays of chlorothalonil alone for the first and final spray in the regimen and when this fungicide was applied with tebuconazole for the second, third, and fourth sprays was as effective as fungicide regimens including combinations of pydiflumetofen plus azoxystrobin plus benzovindiflupyr, mefentrifluconazole plus pyraclostrobin plus fluxapyroxad, bixafen plus flutriafol, and prothioconazole plus tebuconazole. Full article

Chlorothalonil and its toxic metabolite, 4-hydroxy-chlorothalonil, pose significant environmental and health risks. However, their simultaneous and accurate detection remains challenging due to their differing ionization efficiencies in mass spectrometry and the interference caused by enzymatic reactions in sulfur-rich vegetables. This study developed a UHPLC-MS/MS method for simultaneous detection of chlorothalonil and 4-hydroxy-chlorothalonil, using an atmospheric pressure chemical ionization (APCI) source, optimizing the probe temperature to 600 °C and a set of optimal chromatography parameters. A low-temperature and acidification synergistic enzyme inhibition strategy was developed, involving refrigerating samples and extraction reagents, acidifying with citric acid before sample homogenization, and extracting with formic acid/acetonitrile, significantly improving chlorothalonil recovery. Method validation demonstrated limits of detection (LOD) and quantification (LOQ) of 0.003 mg/kg and 0.01 mg/kg, respectively, with recoveries of 76.5–91.1% for chlorothalonil and 87.6–96.7% for 4-hydroxy-chlorothalonil. The method was successfully applied in monitoring the residue risks in sulfur-rich vegetables. Full article

Stem segments of Acacia mangium and A. auriculiformis containing full axillary buds were used to study the effects of reduced amounts of the main nitrogen source in the growth media. This condition, referred to as nitrogen deficiency in this article and denoted as -N, involved the omission of ammonium nitrate and potassium nitrate from MS media, and its impact on bud induction was assessed. The results show that in media lacking nitrogen, the bud induction rate, contamination rate, browning rate, stem length, and leaf number of induced buds of A. mangium and A. auriculiformis varied depending on the different culture media used. The optimal bud induction medium for A. mangium and A. auriculiformis was as follows: 1/4MS (-N) + 1.0 mg·L⁻¹ 6-BA + 0.2 g·L⁻¹ chlorothalonil + 5 g·L⁻¹ AGAR. The bud induction rates were 72.6% and 100.0%, respectively. There were no significant differences in the rooting rates of the induced buds between the -N treatment and the complete nutrient treatment. We found that the buds induced in the -N media did not show obvious symptoms of nitrogen deficiency, and their growth status was not significantly different from those induced in the complete nutrient media, which indicates that nitrogen is not essential for the bud induction of A. mangium and A. auriculiformis. The results of this study provide an important reference for conducting related research on other plants and have are greatly significant for the sustainable development of tissue culture technology in the future. Full article

Foliar diseases caused by various fungi severely affect the yield and quality of banana crops. This study was conducted to clarify the biological characteristics of Bipolaris oryzae (teleomorph: Cochliobolus miyabeanus), a pathogen reported in 2023 as a new etiological agent of leaf spot in the banana variety ‘Pisang Mas’ (Musa acuminata, AA group) in Hainan Province, China, and to screen effective fungicides for its control. The results indicated that banana leaf extract agar (BLEA) and cornmeal agar (CMA) were the best media for the growth and sporulation of the pathogen, respectively. The pathogen grew best on a Czapek’s agar (CZA) medium with sucrose as a carbon source and yeast extract as a nitrogen source, while the optimal carbon and nitrogen sources for sporulation were lactose and beef extract, respectively. The pathogen could grow within a temperature range from 5 °C to 35 °C, and the optimal temperatures for growth and sporulation were 30 °C and 25 °C, respectively. Exposure to 50 °C for 10 min was lethal. Additionally, the pathogen could grow and sporulate within pH ranges of 4 to 10 and 4 to 9, respectively, and the optimal pH values for growth and sporulation were 5 and 8, respectively. The optimal photoperiods for growth and sporulation were 16 h light/8 h dark and 24 h light, respectively. Among the 12 tested fungicides, 500 g/L of iprodione SC showed the highest toxicity against B. oryzae, with an EC₅₀ value of 0.08 μg/mL, followed by 30% difenoconazole-azoxystrobin SC and 125 g/L of epoxiconazole SC, with EC₅₀ values of 0.13 μg·mL⁻¹ and 0.20 μg/mL, respectively. A fungicide containing 40% chlorothalonil SC had the poorest fungicidal activity, with an EC₅₀ value of 155.98 μg/mL. An artificial inoculation pot experiment showed that 125 g/L of epoxiconazole SC at 250 μg/mL, 500 g/L of iprodione SC at 1667 μg/mL, and 30% difenoconazole-azoxystrobin SC at 250 μg/mL provided a protective control efficacy of 100% against B. oryzae, while 125 g/L of epoxiconazole SC at 250 μg/mL and 500 g/L of iprodione SC at 1667 μg/mL provided a curative control efficacy of greater than 60%. This study clarified the optimal conditions for the mycelial growth and sporulation of B. oryzae isolated from banana and screened out fungicides with effective inhibitory activities. These results can provide guidance for field applications and the management of leaf spot caused by B. oryzae in banana. Full article

In this study, C18-functionalized magnetic silica nanoparticles (Fe₃O₄@SiO₂@C18) were used as adsorbents for the magnetic solid-phase extraction (MSPE) of organic contaminants commonly applied to aquaculture water (organic booster biocides, herbicides, and insecticides) followed by Gas Chromatography coupled to Mass Spectrometry (GC–MS). The extraction conditions and efficiency of the nanoparticles for the determination of ten pesticides (atrazine, ethoxyquine, chlorothalonil, chlorpyriphos methyl, methyl parathion, chlorpyriphos, resmethrin, λ-cyhalothrin, permethrin, and irgarol) were thoroughly investigated. Several experimental parameters affecting the extraction efficiency such as the amount of sorbent, extraction time, and elution time were optimized by employing experimental designs as response surface methodology. Validation experiments showed that the average recoveries of target analytes were in the range of 60% to 99%. The optimized method exhibited good linearity (R² > 0.9901) and satisfactory precision (Relative Standard deviations, RSDs < 15%). The method detection limits ranged between 1.9 ng L⁻¹ and 62 ng L⁻¹. Finally, the MSPE method was successfully applied to aquaculture water samples collected from the Thesprotia region (N.W. Greece), Thermaikos Gulf (N. Greece) and Butrint (S.W. Albania). Full article

This study investigated the photocatalytic degradation of chlorothalonil under a range of ultraviolet lamp configurations, and studied the improvement in the photocatalytic degradation efficiency of a reflective material (silver-white aluminium foil). Increasing the number of UV lamps significantly enhanced degradation efficiency, reducing the half-life from 29.95 min with one lamp to 8.15 min with four in a 20 cm enamel bucket. The use of silvery-white aluminium foil further decreased the half-life to 3.86 min, improving degradation rates by up to 262.9%. In larger containers, degradation efficiency increased by up to 414.7% with aluminium foil. Comparisons with black aluminium foil confirmed that silver-white aluminium foil enhanced degradation by reflecting and redistributing UV light, increasing intensity by 252% and reducing the CTL half-life from 150.36 min to 22.9 min in a controlled light box. Further tests confirmed that silver-white aluminium foil amplified UV irradiation, increasing degradation efficiency by up to 555.1%. These improvements might suggest that aluminium foil enhances UV utilisation through direct reflection, refraction, and diffuse reflection, effectively redirecting photons that would otherwise escape the system. Experiments with natural water sources showed similar trends, with half-lives of 55.23 min in ultrapure water, 12.63 min in pond water, and 16.36 min in paddy field water. The addition of silver-white aluminium foil further reduced these times to 23.92 min, 7.13 min, and 12.34 min, respectively. These findings demonstrate that silvery-white aluminium foil significantly enhances CTL photodegradation without increasing energy consumption. While effective, the method faces challenges in acidic or alkaline wastewater due to potential corrosion of system components. Future research should focus on identifying stable, high-reflectivity materials for long-term applications. This study offers practical insights into the optimisation of photodegradation processes, which contributes to improved water treatment strategies and environmental pollution mitigation. Full article

Arbuscular mycorrhizal fungi (AMF) and phosphorus-solubilizing bacteria (PSB) play crucial roles in enhancing crop growth, increasing yields, and improving the soil microbial environment. The aim of this study was to investigate the effects of microbial inoculation and chlorothalonil on the AMF colonization rate in soybean roots, AMF spore density, nodule number, soybean biomass, and the composition of bacterial communities associated with soybean rhizosphere soil and AMF spores. The results indicated that the AMF colonization rate in soybean roots, AMF spore density, nodule number, and soybean biomass in the treatment inoculated with both Rhizophagus intraradices and Acinetobacter calcoaceticus were significantly greater than those in the other treatments. Inoculation with R. intraradices and A. calcoaceticus and spraying with chlorothalonil could influence the bacterial diversity in the rhizosphere soil of soybean. Compared with that in the control treatment, the relative abundance of Firmicutes in the rhizosphere soil of soybean plants inoculated with R. intraradices increased by 1.40%. In addition, both spraying with chlorothalonil and inoculation with A. calcoaceticus influenced the composition of AMF spore-associated bacterial communities. The relative abundance of Proteobacteria in AMF spore from soybean rhizosphere soil inoculated with R. intraradices and A. calcoaceticus increased by 12.42% compared to that in samples inoculated solely with A. calcoaceticus. This study provides a theoretical basis for microbial inoculation in improving the microenvironment of soybean rhizosphere soil and increasing soybean biomass. Full article