环境•农林最新文献

In densely populated urban areas, where separate waste collection is impractical, waste management strategies should be structured within a sustainable framework to ensure environmental efficiency and resource optimization. High-moisture kitchen waste (KW) impairs the efficiency of incineration technology, which remains the most effective method for reducing the volume and mass of municipal solid waste (MSW). Conversely, the high proportion of readily biodegradable organics in KW makes biodrying—a process that generates heat through microbial decomposition—a promising alternative for enhancing the combustion quality of MSW. This study aims to contribute to the sustainable management of MSW by investigating the biodrying and biodegradation behaviors of KW. In the first phase, the biodrying process was evaluated through variations in temperature, mass loss, and relative humidity. The trial containing 10% bread waste (BW) reached the highest temperature (60 °C), whereas the most efficient moisture removal (43.75%) occurred under the highest airflow rate (AFR) of 3.2 m³/kg waste/day. In the second phase, respiration tests were performed to assess the biodegradation kinetics of the trials. A first-order kinetic model was applied to estimate biodegradation coefficients and maximum oxygen consumption (L). High R² values (≥ 0.99) validated the suitability of the applied kinetic model. Such kinetic approaches may serve as promising tools for future modelling efforts in biodrying research.

The dual global health crises of antimicrobial resistance and cancer demand the urgent discovery of novel therapeutic leads. The medicinal plants Cynanchum viminale and Pergularia daemia (Apocynaceae) represent a rich reservoir of bioactive compounds used in traditional medicine, yet a comprehensive comparative analysis of their bioactivities and molecular mechanisms has remained elusive. This study provides an integrated in vitro and in silico analysis of the methanolic extracts of C. viminale and P. daemia. Phytochemical profiles were delineated by HPLC. Bioactivities were systematically evaluated via a battery of five antioxidant assays (DPPH, ABTS, FRAP, H₂O₂, NO), broad-spectrum antimicrobial screening against six pathogens, and cytotoxicity assays against a panel of six human cancer cell lines (HepG-2, MCF-7, HCT-116, A-549, PC-3, A-431). To deconstruct the molecular basis of these activities, in silico molecular docking was performed against two pivotal therapeutic targets: Epidermal Growth Factor Receptor (EGFR) and Dihydrofolate Reductase (DHFR). A striking functional divergence between the two plants was discovered. P. daemia exhibited superior antioxidant and broader-spectrum antibacterial activity, a finding strongly correlated with its unique phenolic profile, particularly the potent DHFR-binding Chlorogenic acid and the bioenhancing alkaloid Piperine. In stark contrast, C. viminale demonstrated dramatically superior cytotoxic potency across all tested cancer cell lines, with IC₅₀ values as low as 24.37 µg/mL against HepG-2 liver cancer. Molecular docking brilliantly illuminated the mechanism behind this divergence: the potent cytotoxicity of C. viminale is driven by its principal alkaloids, Protopine and Berberine, which showed high-affinity binding to the ATP-binding site of EGFR, a key driver of cancer proliferation. DHFR, conversely, was identified as a common molecular target for potent binders from both plants (Evodiamine, Piperine, Chlorogenic acid), providing a unifying mechanism for their shared antimicrobial properties.

This research aims to tackle the issue of increasing harmful pollutants in the environment by creating monodispersed silica hybrids, namely vinyl ormosil (VO) and phenyl ormosil (PO), and assessing their effectiveness as phenol adsorbents in aqueous solutions. To comprehend the correlation between structural attributes and functionality, such hybrid materials are analyzed based on surface and bulk properties. Attaining monodispersity, a defining characteristic of ormosils, is a crucial element in the synthesis process, requiring meticulous scrutiny of several factors. The ATR-FTIR spectra of the monodispersed silica hybrids display distinct characteristics, notably a decrease in Si–O-Si linkages. The formation of Si–O-Si bonds in silica hybrids is due to cross-linking, leading to two distinct peaks at 1050 cm⁻¹ and 1149 cm⁻¹, which correspond to Si–O and Si–C fragments, respectively. It was evident the synthesized adsorbents monodispersed silica ormosils VO and PO were efficient enough to remove 90% of nitrophenol and aminophenol. It suggested that the saturation or unsaturation of the organic moiety with conjugation influenced binding efficacy. This study enhances comprehension of the design and utilization of nanostructured materials for environmental remediation.

Cyanide (-C≡N) pollution from industrial activities significantly threatens ecosystems and human health. The application of cyanide (CN) in mining, electroplating, and chemical synthesis as well as discharge from industries including steel plants have increased environmental contamination and associated threats to the biota. The estimated global CN production figure for the year 2022 from these sources i.e. 1.3 million metric tons is a testimony to the growing cyanide pollution and increasing associated environmental and health concerns around the world. CN spills and improper disposal into waterbodies have resulted in serious environmental pollution, and caused human fatality due to acute toxicity affecting the nervous system and tissues with high oxygen metabolism. This review discusses environmental and health consequences of CN pollution, its origin, toxicological effects, regulatory measures, and available remedial technologies. Environment friendly bioremediation methods and hybrid technologies such as electro-biodegradation and microbial fuel cells among others hold promise for reducing CN pollution. Exploring patented technologies from different countries for their possible integration while developing novel cleanup solutions may also be a viable option . Regulatory frameworks are critical for managing cyanide disposal. Deployment and implementation of high-quality wastewater treatment technologies are prerequisites for taking up any CN-specific mitigation measure. The use of emerging biotechnologies along with the other technologies may be an effective future strategy for developing sustainable cyanide remediation technologies in general and to treat the CN contaminated water bodies, in particular.

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In this study, the chemical constitution and microbial heterogeneity of a natural soda water spring situated in Çerme Village, Turkey were examined. In the chemical assessments, it was ascertained that several parameters such as pH, calcium, magnesium, chloride, bicarbonate and total organic matter were in accordance with potable water criteria. However, it was determined that some elements such as manganese (0.83487 mg/L), nitrite, ammonium, iron, aluminum, copper and sulfur exceeded the limit values. A total of 12 bacteria were isolated using culture-based methods and these isolates were identified at species level. The bacteria that were isolated are composed of the genera Staphylococcus, Kurthia, Micrococcus, Pseudomonas, and Listeria. The Shannon diversity index (H′ = 1.86) suggests that there is moderate microbial diversity. It is worth mentioning that the very high concentration of manganese seems to be the main factor in this spring ecosystem—the survival of metal-tolerant environmental bacteria is the result of selective pressure that is exerting strong influence. The findings from this research indicate the importance of periodical examination of natural water sources that have been traditionally used. In addition, these findings reveal significant patterns of bacterial diversity in areas contaminated with metals.

Fast-growing amount of waste activated sludge (WAS) has awoken concerns on its environmental hazards and called forth appropriate treatment procedures. This study investigated low-strength ultrasound (25 kHz) effects on sludge for durations from 30 to 120 s. Results demonstrated that sludge oxidative status maximized to 54.34 × 10⁻⁶ mol/L at 60 s, whereas soluble chemical oxygen demand increased to 5438 mg/L till 120 s, respectively. Three-dimensional excitation-emission matrix with quantitative analysis on dissolved organic matters of extracellular polymeric substances (EPS) revealed that fluorescence intensities of fulvic acid, soluble microbial metabolites (SoMM), and humic acid of soluble EPS increased at 60 s, and the counterparts of tyrosine and SoMM in loosely- and tight-bound EPS were enhanced from 60 to 120 s, which indicated the decrease of counterparts in WAS, therefore helping sludge dewaterability and reduction. Low-strength ultrasound increased sludge community diversities and shifted communities’ structures, and dominant genera, including Methylotenera, Ferruginibacter, Candidatus_Competibacter, Saprospiraceae, Caldilineaceae, and Dokdonella, were shared in common, whilst Kapabacteriales, Nitrospira, Haliangium, and Macellibacteroides, Bacteroides, Arcobacter, Paludibacter, Trichococcus varied due to sludge source differences. Functional prediction indicated no significant changes of dominant metabolic pathways or enzymes after ultrasonic treatment, meanwhile pathways and KOs correlating with organic matter metabolisms (e.g., ko00010, ko01200, and K00059) were enhanced. Phenotype prediction showed that ultrasound reduced relative abundances of “biofilm formation”, “oxidative stress tolerant”, “facultative anaerobic”, and “anaerobic”, however increased that of “aerobic”, and dominant genera contributing to phenotypic variations comprised Methylotenera, Caldilineaceae, Dokdonella, Candidatus_Competibacter, and Saprospiraceae, Macellibacteroides, Trichococcus, and Paludibacter.

Sulfation of active sites and competitive SO₂ adsorption critically limit the durability of NH₃-SCR catalysts for industrial NO_X abatement. Here, we investigate Iron (Fe) and Praseodymium (Pr) doped CeMnO_X catalysts synthesized via an acid-etching-assisted hydrothermal method, focusing on mechanistic differentiation of Fe-doped catalysts’ sulfur resistance function. The Fe-doped catalyst achieves > 95% NO conversion for 20 h at 200 °C under 50 ppm SO₂, while maintaining oxygen mobility (O_β/O_α ratio decreased from 89.02% to 70.29%) and enhanced surface acidity (1.10 → 2.60 mmol g⁻¹). Staged in situ DRIFTS reveals that surface-bound NH₄⁺ and NH₃ ligands, associated with Brønsted and Lewis acid sites, respectively, serve as key intermediates. Their transformation into nitrate and nitrite species confirms coexisting Eley–Rideal and Langmuir–Hinshelwood pathways. Co-adsorption studies demonstrate the simultaneous presence and mutual reactivity of NH₃ and NO_X species over time. Upon SO₂ exposure, reactive intermediate bands remain stable, and only weakly bound sulfur-related species are transiently detected—indicating minimal irreversible sulfur deposition. These findings, corroborated by H₂-TPR and XPS (FeSO₄ formation), clarify Fe-doped catalysts’ dual-function role in preserving redox sites while mitigating sulfation. Pr dopant isolates Fe-specific behavior, decoupling redox promotion from SO₂ shielding. This work provides molecular-level insights for designing robust, multifunctional SCR catalysts for SO₂-laden environments.

Metal sulfide precipitation is a metal removal process in industrial effluents that is used for the recovery and safe disposal of metals. The main objective of this work was to establish the conditions necessary to carry out the selective precipitation of metals in upflow anaerobic sludge blanket (UASB) reactors. Two reactors were inoculated with sulfate-reducing microorganisms for the treatment of water from the flotation unit operation of a mining company. Reactor UASB 1 operating volume was 1.9 L whereas UASB 2 was 3.4 L. The first one operated under acidic conditions and the second one at conditions close to neutrality. The history of operation of UASB 1 reactor has been working for several years in a stable manner, and UASB 2 for only six months. Each received the same influent at the same hydraulic residence time (12.6 days). Both reactors achieved a good sulfate reduction of 84 and 82%, respectively. Removal of organic matter, measured as total organic carbon, was 3% higher in UASB 1 than in UASB 2. UASB 1 removed 28.5% more Zn, 32.4% more Cu, and 48% more Fe than did UASB 2. However, UASB 2 removed 30% more Pb than did UASB 1. To achieve selective precipitation, the reactors should operate at the effective pH conditions for each metal, an area of opportunity to continue research seeking its applicability on a real scale.