Search Results (560)

To control the impact of the invasive crayfish Faxonius limosus on native crayfish and fish biodiversity in the Danube River ecosystem, one possible approach is the valorization of this species through the production of value-added biopolymers, considering the continuously increasing demand for chitosan. However, there are very limited data regarding the utilization of Faxonius limosus shell waste as a source of chitosan. Therefore, this study evaluated chitosan recovery from spiny-cheek crayfish shell, including conventional chemical treatment with different demineralization intensities and numbers of deproteinization steps, as well as ultrasound and autolysis-assisted deproteinization. The obtained chitosans were characterized in terms of yield, moisture content, degree of deacetylation, color, crystallinity and structural properties. Residual heavy metal concentrations (Hg, Cd and Pb) were determined to assess the safety of crayfish shell as a raw material intended for food-related applications. Particular emphasis was placed on gel-related functional properties of obtained chitosans, including rheological behavior, wettability on fruit surfaces, antioxidant and antimicrobial activities, and film-forming ability. These properties govern the formation of structured biopolymeric networks and their performance as active food coating materials. The relationships between the extraction process, physicochemical characteristics and functional performance were investigated to identify the most suitable chitosan for potential food preservation applications. The results demonstrated that extraction conditions significantly affected the physicochemical and functional properties of chitosan. Samples obtained through intensive deproteinization showed enhanced antimicrobial activity, whereas higher antioxidant activity was observed in samples containing residual bioactive compounds. Most formulations exhibited suitable wettability on apple and nectarine surfaces and successfully formed transparent films, indicating their potential application as edible coatings. Full article

Automotive paint sludge (APS) is a hazardous industrial waste generated during automotive coating operations and is characterized by high moisture content, variable organic and inorganic composition, volatile organic compounds, pigments and heavy metals. Conventional disposal methods, including landfilling and direct incineration, present increasing environmental and regulatory challenges, thereby motivating interest in thermochemical conversion technologies for APS valorization and energy recovery. This review evaluates the current state of research on APS thermochemical conversion through incineration, pyrolysis and gasification pathways. The review compares the major operational characteristics of thermochemical pathways, including reactor conditions, temperature ranges, product yields, energy recovery potential, pollutant formation and downstream cleanup requirements. Also, techno-economic considerations such as drying energy demand and scale-up limitations are discussed. According to the current literature, incineration is the most industrially mature route for APS destruction, whereas pyrolysis offers more flexibility for fuel and material recovery. Gasification shows potential for syngas and hydrogen production but remains insufficiently studied for APS applications. Despite growing interest in APS valorization, a lot of research gaps remain regarding standardized feedstock classification, pilot-scale validation, process integration, environmental risk assessment and techno-economic optimization. Conclusively, future approaches towards managing APS would need to incorporate process optimization for specific APS types, incorporation of co-processing techniques, as well as an overall assessment for both environmental and economic feasibility. Full article

This Editorial introduces the Special Issue “Emerging Technologies for Waste Treatment, Pollution Control and Resource Recovery”, which examines how contemporary environmental engineering is moving beyond conventional end-of-pipe treatment toward integrated, circular, and systems-oriented approaches. The collected contributions address sustainability innovation in textile manufacturing, life-cycle-informed PFAS removal from landfill leachate, fishbone-derived hydroxyapatite adsorbents for heavy metal removal, and constructed wetlands for azo dye degradation. Together, these studies demonstrate that effective waste treatment must be evaluated not only in terms of pollutant removal efficiency, but also by material circularity, secondary environmental burdens, operational feasibility, and long-term contaminant fate. This Editorial highlights key cross-cutting themes, including the valorization of residual materials, the importance of realistic matrices and field validation, and the need to integrate life cycle assessment, techno-economic analysis, and mechanistic investigation early in technology development. It further identifies major research gaps concerning spent media management, regeneration, toxicity, transformation products, and scale-up under variable operating conditions. Overall, this Special Issue proposes a framework in which emerging waste treatment technologies are understood as multifunctional environmental systems that support pollution control, resource recovery, and resilient circular economies. Full article

Heavy metal stress severely impairs global agricultural productivity, a challenge exacerbated by rising industrial activities. To mitigate chromium (Cr) toxicity in crops, this study evaluated the potential of seed priming with four distinct acids, ascorbic acid (AA), citric acid (CA), nitric acid (NA), and salicylic acid (SA), on broad bean (Vicia faba L.) seedlings exposed to 50 ppm Cr(VI). Cr(VI) exposure alone severely compromised development, reducing root and shoot fresh biomass by 47% and 52.3% and lengths by 60.8% and 62.19%, respectively. This growth inhibition was mirrored by a massive drop in total soluble sugars (over twofold in shoots and threefold in roots) and a twofold spike in toxic hydrogen peroxide (H₂O₂) accumulation. However, acidic priming agents effectively protected the seedlings from this oxidative crisis. The co-application of these effectors limited the inhibitory effects of Cr(VI), increasing biomass up to twofold and reducing H₂O₂ levels by around 32% in roots and 26% in shoots. This reduction in oxidative damage subsequently alleviated cellular stress, restoring protein content (by up to 70.72% in shoots under AA) and bringing catalase (CAT) and ascorbate peroxidase (APX) activities back toward baseline levels, reducing them by more than 50% compared to the unprimed Cr(VI) control. Notably, regarding bioaccumulation, only AA priming significantly limited heavy metal uptake, reducing chromium accumulation by 36.5% in roots and 26.5% in shoots. This unique protection is likely linked to a potential chemical reduction of mobile Cr(VI) near the root boundaries and the regulation of internal osmoprotectant systems. These findings suggest that seed priming with these effectors, especially AA, offers a highly scalable, low-cost, and sustainable strategy for enhancing crop tolerance in heavy-metal-polluted soils. Full article

This review is devoted to the occurrence, extraction, structural characterization and catalytic applications of vanadyl porphyrins present in heavy crude oils and petroleum residues. Vanadyl porphyrins represent the major vanadium-containing compounds in petroleum systems and play a dual role as both catalyst poisons during refining processes and valuable precursors for functional catalytic materials. Particular attention is devoted to recent advances in extraction technologies, including solvent extraction, ionic liquids, deep eutectic solvents, functionalized adsorbents and chelating agents. Process intensification approaches such as ultrasound- and microwave-assisted extraction, are also discussed as promising strategies for improving extraction efficiency and selectivity. Furthermore, recent developments in petroleum characterization using FTICR-MS, EPR, HYSCORE and LA-ICP-MS techniques are reviewed, providing insights into metalloporphyrin speciation, oxidation states, and distribution within complex petroleum matrices. Beyond their traditional role in catalyst deactivation, vanadyl porphyrins have emerged as attractive precursors for catalytic materials applied in oxidation reactions, photocatalysis, oxidative desulfurization, wastewater treatment and selective organic synthesis. The development of hybrid catalytic systems based on mesoporous silica, graphene oxide, carbon nanotubes, polymer matrices, and metal–organic frameworks has significantly improved catalyst stability, activity and recyclability. Current challenges related to the selective extraction, preservation of metalloporphyrin structure and catalytic performance evaluation are also discussed. Overall, this review provides an integrated perspective on the recovery, characterization and valorization of vanadyl porphyrins for sustainable petroleum upgrading and environmental applications. Full article

The increasing generation of textile cotton waste (TCW) and textile wastewater sludge (TWS) presents significant environmental management challenges. This study evaluates the conversion of TCW and TWS into biofuel pellets for waste recovery and coal substitution. Pellets were prepared at TWS ratios of 20:80, 40:60, 60:40, and 80:20 and assessed through combustion emission analysis, ash characterization, cradle-to-gate carbon assessment, and equal-energy cost comparison with imported bituminous coal. Increasing the TWS fraction prolonged combustion duration and increased SO₂ and NO_x emissions; however, all oxygen-normalized emissions remained within Sindh Environmental Quality Standards (SEQS) limits under the tested conditions. The 20:80 blend exhibited the lowest emission factors, with CO, SO₂, NO_x, and CO₂ emissions of 1.03 g kg⁻¹, 3.81 g kg⁻¹, 1.57 g kg⁻¹, and 1.42 kg kg⁻¹, respectively. Ash analysis showed that Cd and Pb were not detected, while measured heavy-metal concentrations remained below U.S. EPA regulatory limits and relevant EU limit values. The 20:80 pellet achieved a cradle-to-gate carbon intensity of 6.6 g CO₂e MJ⁻¹, approximately 59% lower than upstream coal production. Equal-energy fuel-cost savings relative to imported coal were 37.6% for the binder-based 20:80 pellet and 83.1% for the binder-free 40:60 pellet. Overall, the results indicate that TCW–TWS pellets, particularly those containing 20–40% TWS, can support textile waste utilization and partial coal substitution while reducing fuel costs. Full article

Industrial wastewater containing refractory organic compounds, heavy metals, and emerging contaminants poses a significant challenge to conventional treatment methods due to their high chemical stability and toxicity. This review systematically summarizes recent advances in Fenton-based advanced oxidation processes (AOPs) for industrial wastewater treatment, with a particular focus on the paradigm shift from homogeneous to heterogeneous catalytic systems. Homogeneous Fenton processes, which rely on Fe²⁺/H₂O₂ reactions, exhibit rapid reaction kinetics but are severely limited by a narrow operational pH range (2–4) and the generation of substantial iron sludge. In contrast, heterogeneous Fenton systems employing immobilized or supported catalysts—such as iron-loaded zeolites, metal–organic frameworks, and carbon-based composites—broaden the applicable pH range to near-neutral conditions (4–8), enable catalyst recovery and reuse over multiple cycles, and enhance process sustainability by reducing iron leaching and sludge production. Integration with external energy inputs—such as photo, electricity, or ultrasound—can further promote radical generation and mass transfer, improving degradation efficiency while reducing chemical consumption. Practical applications in treating wastewater from textile, pharmaceutical, and electroplating industries have demonstrated effective contaminant removal and enhanced biodegradability. However, most current research remains at the laboratory scale, with long-term catalyst stability, operational costs, and scalability representing major barriers to large-scale implementation. Future research should focus on developing stable and regenerable catalysts, advancing pilot-scale studies of integrated systems, and conducting long-term evaluations under real wastewater conditions to promote the development of efficient, low-carbon, and sustainable solutions for industrial wastewater treatment. Full article

Cocoa processing generates large amounts of agro-industrial by-products, mainly cocoa bean shells (CBS), cocoa pod husks (CPH), and cocoa mucilage, which remain underutilized despite their nutritional and bioactive potential. This narrative review critically analyzes the composition of cocoa by-products and emerging technologies for bioactive compound recovery. Results show that CBS and CPH are rich sources of dietary fiber (13.8–65.6%), phenolic compounds (up to 100 mg GAE/g), and methylxanthines (theobromine up to 11.6 mg/g in CBS). Emerging extraction technologies, ultrasound-assisted extraction, pressurized liquid extraction, microwave-assisted extraction, pulsed electric fields, and cold atmospheric plasma, improve extraction yield (20–150%), reduce processing time (from hours to minutes), and decrease solvent consumption compared to conventional methods. Regarding food applications, moderate CBS inclusion levels (10–20% in cookies, 2–8% in bread, 0.75–1.0% in sausages) improve dietary fiber and antioxidant capacity without compromising sensory acceptability, whereas higher levels (>20–30%) increase hardness, bitterness, and astringency. It is concluded that cocoa by-products are promising resources for sustainable functional food ingredients. However, industrial implementation remains limited by raw material variability, lack of standardized extraction protocols, sensory constraints, and insufficient biological validation of recovered compounds. Future research should focus on standardizing extraction protocols, validating bioaccessibility and bioactivity through in vivo studies, optimizing food formulations for sensory balance, assessing contaminants (heavy metals, mycotoxins), and evaluating techno-economic feasibility and life-cycle sustainability at industrial scale. Full article

Agricultural and food-processing residues, as well as fruit by-products, represent widely available but still underutilised resources. Although numerous laboratory-scale studies have demonstrated their ability to remove heavy metals from contaminated water, their practical implementation remains limited by incomplete understanding of long-term stability, regeneration efficiency, and end-of-life environmental safety. This review critically evaluates the current state of biosorbent research, with particular emphasis on the full life cycle of these materials, including adsorption performance, regeneration strategies, repeated-use potential, and post-exhaustion management. While focusing primarily on agricultural residues, the review also integrates key findings from alternative materials such as algae, microbial biomass, and industrial sludge to provide a comprehensive evaluation. Particular attention is given to the distinction between desorption and regeneration, metal recovery from desorption streams, and the associated environmental burden of secondary waste generation. In addition to commonly proposed valorisation routes, such as incorporation into construction materials, thermal conversion, and reuse in energy or catalytic applications, the review highlights that most end-of-life pathways remain partial solutions rather than true closed-loop systems. In many cases, only a small fraction of spent biosorbents can be effectively incorporated into secondary products, while remaining residues still require further treatment or disposal. The lack of standardised criteria for defining biosorbent exhaustion and performance thresholds further limits comparability across studies and hinders scale-up. Overall, current evidence suggests that biosorbent-based wastewater treatment should be considered a promising but still partially circular system, where full material closure has not yet been achieved. Addressing these gaps is essential for advancing toward more robust and environmentally sustainable implementation and for improving the circularity of biosorbent-based wastewater treatment systems. Full article

Cadmium (Cd) is an environmental nephrotoxicant that preferentially accumulates in the kidney and disrupts redox and energy metabolism. However, the protective effect of berberine (Ber) against Cd-induced nephrotoxicity remains insufficiently characterized. In the present study, male C57BL/6 mice were orally exposed to CdSO₄ (30 mg/kg body weight/day) for 30 days in the absence or presence of berberine (25 or 100 mg/kg/day). Renal function, histopathology, oxidative stress parameters, LC–MS/MS-based metabolomic profiling, gene and protein expression, and in silico ligand–target interactions were evaluated. Cd exposure markedly increased serum CREA, renal index, renal LDH activity, and MDA content, decreased SOD and CAT activities, and induced pronounced renal histopathological lesions. Ber significantly attenuated these abnormalities in a dose-dependent manner. Metabolomic analysis revealed that Cd broadly suppressed pyruvate metabolism, tricarboxylic acid cycle intermediates, and NAD+/NADH homeostasis, whereas berberine restored the levels of pyruvate, acetyl-CoA, oxaloacetate, citrate, isocitrate, succinate, fumarate, malate, NAD+, and NADH. In parallel, berberine normalized the expression of metabolism-related genes including the downregulation of Ldha and the upregulation of Cs, Sucnr1, G6pc, and Pfkm, with the high-dose regimen showing the most evident recovery. Western blotting further verified the lower LDHA protein expression after berberine treatment. Molecular docking demonstrated favorable potential berberine–LDHA binding, and molecular dynamics simulation supported the stability of the ligand–protein complex. Collectively, these findings indicate that berberine ameliorates Cd-induced renal injury, an effect that correlates with attenuated oxidative stress, modulation of LDHA-associated glycolytic pathways, and restoration of mitochondrial TCA-cycle activity and redox balance, highlighting berberine as a promising candidate for the prevention of heavy metal-associated nephrotoxicity. Full article

Lead exposure remains a pervasive environmental and public health threat, imposing a substantial burden of neurodevelopmental and cognitive dysfunction, yet safe mechanism-oriented interventions remain limited. Genistein, a soybean-derived isoflavone with antioxidant and neuroprotective potential, may counter heavy metal-induced neural injury; however, whether its efficacy is associated with redox–metabolic remodeling is unclear. Here, we evaluated genistein in lead-exposed C57BL/6J mice and lead-challenged HT22 hippocampal neurons. Genistein improved novel-arm exploration and spatial memory without altering locomotor or swimming performance, and attenuated neuronal disorganization and apoptosis in hippocampal CA1, CA3 and dentate gyrus regions. These protective effects were accompanied by reduced blood and hippocampal lead accumulation, restored glutathione redox balance, enhanced antioxidant capacity, preserved mitochondrial integrity, and suppressed Bax/Caspase-3-associated apoptotic signaling. Importantly, because genistein also reduced hippocampal lead accumulation, the in vivo neuroprotection may reflect both reduced target-tissue lead burden and improved glutathione-related redox homeostasis. Untargeted metabolomics identified 59 genistein-responsive metabolites enriched mainly in glutathione metabolism, oxidative phosphorylation, and ascorbate/aldarate metabolism, linking metabolic remodeling to behavioral recovery and reduced oxidative-apoptotic injury. In HT22 cells, blockade of glutathione synthesis by buthionine sulfoximine markedly weakened genistein-mediated cytoprotection, mitochondrial membrane potential recovery, and apoptosis inhibition. Collectively, genistein mitigates lead-induced hippocampal neurotoxicity and cognitive impairment by restoring glutathione-centered redox–mitochondrial homeostasis, supporting its further development as a mechanistically defined dietary candidate for environmental pollutant-associated neural injury. Full article

At present, treated wastewater may still contain residual nutrients and micropollutants, including heavy metals, pharmaceuticals, and dyes, which can negatively affect receiving water bodies. Increasingly stringent environmental regulations, including Directive (EU) 2024/3019, require both enhanced removal of these contaminants and greater integration of renewable energy sources in wastewater treatment plants. This paper presents a review of biomass-based wastewater polishing technologies employing biological agents such as microalgae, fungi, bacteria, co-cultures and duckweed for the removal of residual contaminants from treated effluents. The compiled data indicate that while optimal conditions can drive pollutant removal efficiencies beyond 90%, system performance varies widely depending on species selection, wastewater characteristics, and operational conditions (e.g., pH, temperature, salinity, nutrient availability, and light intensity). In addition to effluent polishing, the produced biomass can be valorized for bioenergy generation, contributing to renewable energy production and supporting circular economy principles in wastewater treatment plants. Despite these benefits, biomass harvesting remains a major technical and economic bottleneck, often representing a significant share of operational costs and limiting large-scale implementation. Overall, biomass-based treatment technologies are a promising approach for improving effluent quality and supporting renewable energy objectives; however, further advances in biomass recovery are required for broader application. Full article

Abiotic stresses, including drought, salinity, alkalinity, temperature extremes, flooding, heavy metals, and emerging pollutants, challenge plant growth and productivity by disturbing water relations, ion balance, redox homeostasis, membrane stability, energy metabolism, and developmental progression. Although substantial progress has been made in the identification of stress-responsive hormones, second messengers, kinases, transcription factors, transporters, and metabolic regulators, plant stress adaptation cannot be fully explained by linear signaling cascades or single tolerance genes. A major unresolved question is how early molecular events are reorganized into coordinated physiological and developmental outputs that support survival, recovery, and productivity. In this review, we propose an intermolecular interaction-driven adaptive remodeling framework for plant abiotic stress responses. This framework emphasizes that stress tolerance emerges from dynamic changes in receptor–ligand recognition, protein–protein interactions, calcium decoding, redox-sensitive modification, phosphorylation networks, transcriptional regulation, chromatin-associated control, and metabolite-mediated feedback. We further emphasize ROS as integrative redox switches that connect stress sensing, defense activation, senescence-related transitions, and recovery, and chromatin-associated mechanisms as regulators that may stabilize primed or memory-like adaptive states. We discuss how these interaction networks converge on core signaling hubs, including abscisic acid, reactive oxygen species, Ca²⁺, and kinase/phosphatase systems, and how they remodel stomatal behavior, root architecture, ion and pH homeostasis, redox buffering, metabolism, development, and reproductive resilience. We further highlight how natural variation, multi-omics, genome editing, high-throughput phenotyping, and field validation can translate interaction-centered stress biology into crop resilience. This perspective provides a conceptual bridge between molecular stress perception, network behavior, physiological adaptation, and climate-resilient agriculture. Full article

Next-generation wastewater treatment and recycling rely on membrane-based processes, but they face a trade-off among permeability, selectivity, and fouling resistance. In the present study, thin-film nanocomposite (TFN) membranes were fabricated by incorporating a ternary TiO₂-SiO₂-biochar nanofiller into a polysulfone (PSf) support using nonsolvent-induced phase separation, after which m-phenylenediamine and trimesoyl chloride were used via interfacial polymerization to produce a selective polyamide layer. The membrane compositions were M1 (22 wt.% PSf), M2 (22 wt.% PSf/0.5 wt.% TiO₂/0.5 wt.% SiO₂/0.5 wt.% biochar), and M3 (polyamide-coated M2). FTIR, XRD, SEM, contact-angle, porosity, and mechanical analyses supported successful membrane formation and changes in morphology, wettability, and structural strength after nanofiller incorporation and TFC coating. The addition of a nanofiller increased the hydrophilicity of the membranes by decreasing the water contact angle from 98.6 ± 0.8° for pristine PSf to 35.6 ± 1.5° for the nanocomposite membrane. Consequently, the pure-water permeability increased from 21 to 37 L m⁻² h⁻¹ bar⁻¹. After polyamide layer formation, the optimized TFN membrane maintained a contact angle of 55.4 ± 3.8° and achieved a high Congo red rejection of 98% with permeate flux of 7–9 L m⁻² h⁻¹ bar⁻¹. The membrane also showed good antifouling performance, with flux recovery ratios exceeding 90%. For heavy-metal-containing solutions, the optimized membrane showed apparent removal efficiencies of 78–98% for multivalent heavy metals (Pb²⁺, Hg²⁺, Cd²⁺, Mn²⁺, Zn²⁺, Cu²⁺, Ni²⁺, Fe³⁺, As³⁺, and Cr⁶⁺). Static adsorption tests showed the order M2 > M3 > M1, confirming that exposed TiO₂-SiO₂-biochar sites contribute to pollutant uptake, while the superior filtration performance of M3 is attributed to the combined effect of the polyamide selective layer and adsorption-assisted interactions. Overall, the TiO₂-SiO₂-biochar-based TFN membrane provides a promising platform for dye removal and preliminary heavy-metal attenuation from contaminated water. Full article

The environmental impacts of treated acid mine drainage on receiving river systems remain insufficiently understood. This study investigated four typical closed coal mines in northern Sichuan Province, China, by analyzing heavy metals, sulfate, pH, UV-Vis spectroscopy, and dissolved organic matter (DOM) characteristics at 24 sampling sites along the receiving reaches. Parallel factor analysis (PARAFAC) and two-dimensional correlation spectroscopy (2D-COS) were employed to examine the longitudinal response sequence of DOM components. Results showed that pollutant concentrations generally increased immediately after the inflow of treated acid mine drainage and then progressively attenuated downstream, although the dominant pollution factors varied significantly among the reaches. DOM composition exhibited spatial heterogeneity, with protein-like components dominating three reaches and humic-like components prevailing in one reach. Based on the co-variation characteristics of DOM and heavy metals along the river course, four response patterns were identified: rapid-recovery, slow-recovery, disturbance–oscillation recovery, and delayed-recovery patterns. The 2D-COS analysis validated the rationality of these four patterns and revealed differences in the sensitivity of various DOM components to longitudinal disturbances. This study provides a scientific basis for the environmental impact assessment of mine water from remediated closed coal mines. Full article