Search Results (2,306)

The world’s food industry faces significant obstacles today as it strives to meet the nutritional needs of its rapidly expanding global population while also managing an immense amount of food processing waste (FPW) generated throughout the entire food supply chain. The widespread use of traditional disposal techniques for food waste (landfilling and incineration) regularly faces challenges related to environmental sustainability and economic efficiency. This manuscript reviews the necessary transition from a linear “take-make-dispose” approach to food production to a more circular model that recycles food waste into high-value intermediate chemicals and renewable energy through the development of biorefineries. The manuscript explores the biochemical composition of food waste, with carbohydrates, lipids, proteins, and bioactive materials, making it a suitable feedstock for different multi-stage biorefinery operations. In addition, this review will evaluate a variety of existing conversion technologies for food processing waste, such as biological methods (e.g., anaerobic digestion and fermentation) and thermochemical methods (e.g., pyrolysis, gasification, and hydrothermal liquefaction), to create various platform chemicals, including organic acids, bio-alcohols and volatile fatty acids (VFAs), as well as the production of sustainable biofuels and biopolymers. The review also elucidates the three most determinative constraints on large-scale industrial implementation of food waste valorisation: feedstock variability, techno-economic feasibility, and the need for comprehensive life cycle assessments (LCAs). The alignment of food waste management strategies with the UN SDGs (in particular, SDG 12 ‘Responsible Consumption and Production’ and SDG 13 ‘Climate Action’) reflects the opportunity for food waste to serve as a foundation for a carbon-neutral, sustainable future. This review provides a strategic roadmap for academics, practitioners, and policymakers to tap into the full potential of food waste through a sustainable circular economy model. Full article

This study explores the behavioral intersection of nutritional health and environmental literacy among pre-service teachers within the national higher education context. Utilizing the Sustainable Healthy Diet Index (SHED Index) for the first time in Croatia, this research systematically examines the dietary habits, lifestyle choices, and socio-cultural patterns of future educators (N = 164) at the University of Split. The survey instrument evaluated the core SHED domains, Healthy Eating (HE) and Sustainable Eating (SE), alongside supplementary indicators monitoring food logistics, hydration, and waste management. Descriptive analysis revealed moderately high standardized overall SHED scores (M = 62.86), aligning with the original normative distribution. Notably, students achieved significantly higher descriptive sub-scores in the HE domain (M = 24.68) than in the SE domain (M = 18.06). Although domestic food consumption and circular recycling practices were well integrated, critical biospheric behaviors—such as reducing animal protein, consuming legumes, purchasing organic food, and composting—remain limited by cultural resistance and municipal infrastructure deficits. Furthermore, an independent t-test indicated no significant differentiation across study levels, highlighting a potential institutional stagnation throughout the five-year teacher education program. Regression analysis demonstrated that sustainable dietary choices appear to be strongly anchored in personal health concerns rather than biospheric altruism, with healthy eating emerging as the single strongest explanatory factor for of sustainable behavior. These findings indicate that to cultivate authentic ecological literacy in the future teaching workforce, higher education curricula require a systemic redesign that explicitly links sustainability to personal well-being through localized, experiential learning. Full article

Ascorbate (AsA), or vitamin C, is a central redox metabolite that functions as an antioxidant, enzyme cofactor, and electron donor. Its cellular function depends not only on biosynthesis or dietary uptake, but also on rapid recycling from its oxidized forms, monodehydroascorbate (MDHA) and dehydroascorbate (DHA). This requirement is especially evident in high-demand systems such as plant chloroplasts, which face continuous photosynthetic reactive oxygen species (ROS) production under illumination, and human neutrophils, which accumulate millimolar ascorbate to withstand NADPH oxidase-driven oxidative bursts in pathogen defense. Here, we revisit ascorbate recycling from a sulfur-centered perspective. Historical studies of plant, animal, and solution-chemistry pathways show that many DHA-reducing systems converge on sulfur chemistry, including glutathione (GSH), cysteine-dependent enzymes, H₂S, and modified thiols. We propose that ascorbate recycling is organized as a multilayered system in which nonenzymatic reactions are accelerated by enzymes, localized within cellular or extracellular compartments, and integrated with broader NAD(P)H-, glutathione-, sulfur-, and diet-dependent redox networks. Within this framework, the AsA/DHA couple can be viewed as a molecular redox capacitor that buffers transient oxidative pressure. Reactive sulfur species (RSS), including persulfides and polysulfides, represent chemically plausible but experimentally unresolved contributors to DHA reduction. Full article

There is an urgent and persistent need to design efficient and sustainable methods to manufacture chemicals on a large scale. Heterogeneous photocatalysts use light to drive organic reactions and offer high recyclability and improved efficiencies for chemical synthesis. However, a detailed study of these photocatalysts using standard laboratory analytical techniques is challenging due to their poor solubility. Successful application of heterogeneous photocatalysts in the chemical industry requires the development of a robust analytical technique that can be used as a predictive and scalable tool for their photocatalytic performance. Herein, we report a simple approach that uses the color of cotton-bound heterogeneous photocatalysts as a potential indicator of their performance. These photocatalysts were synthesized by covalently attaching perylene-based molecular photocatalysts to the surface of cotton using amino-substituted triethoxysilane as the linker. Colorimetry coupled with NMR analysis revealed two important findings: (i) cotton-bound photocatalysts catalyzed sulfide oxidation to sulfoxide under blue-light illumination, and (ii) a general relationship was observed between color intensity and catalytic performance, with darker samples generally exhibiting faster reaction rates. These findings suggest that color may serve as a simple and rapid tool for assessing photocatalyst performance. Future studies will focus on enhancing the reproducibility of photocatalyst binding procedures and validating the color–performance relationships in a wider range of color intensities of the cotton-bound photocatalysts. Full article

São Paulo is the largest city in Brazil and the second in Latin America. Its domestic waste production reached 3,515,678.96 tons in 2024. Historically, the city has a low recycling rate, and several laws and policies have been implemented to reverse this situation. The objective of this study was to investigate whether there have been advances in the recycling of household solid waste in São Paulo 15 years after the National Solid Waste Policy, from municipal and intra-urban perspectives. The extended period studied and segregated data by regional administration represent the innovative approach of this manuscript. The methodology consisted of a case study with an analysis of the legislation, official data research and evaluation of goals, and socio-spatial distribution. The separate collection rate grew from 0.69% in 2006 to 2.85% in 2024, but this volume represents less than 10% of the target originally projected for the period. A socio-spatial inequality was found as well as a lack of dedicated collection for the organic fraction. It can be concluded that progress is incremental, but limited by structural barriers and urban inequities. Results indicate for São Paulo and for other large cities, mainly in low and middle-income countries, recycling success cannot depend on legislation as it is also correlated with demographic factors, such as educational level, and to the need of targeted policies for a progressive increase in source-separated recycling. Full article

In strong-flavor Baijiu brewing, surface spraying of recycled distillation tail liquor (TL) leads to volatile aroma loss, uneven substrate distribution and localized fermentation inhibition. A patented telescopic subsurface injector was adopted to deliver 0–30 kg TL per pit at a 50 cm depth on fermentation day 30, the critical transition point between acidogenesis and esterification. At the highest dosage (30 kg), total esters rose 14.8% (from 4.45 to 5.11 g/L), with ethyl hexanoate up 52.2% (to 1.72 g/L) and ethyl lactate up 69.8% (to 3.82 g/L). Fermentation temperature curves stayed unchanged, and grain-derived ethanol yield remained near 38.2% in all groups after correcting for the ethanol already present in the added TL. Subsurface injection of tail liquor-supplying ethanol and organic acid precursors-at the acidogenesis-to-esterification transition enhances ester synthesis without disrupting fermentation or reducing distillate yield. Acid profiles were also stable, suggesting that the added substrates were channeled into ester synthesis rather than acid accumulation. Targeted subsurface TL injection at this metabolic transition thus represents an industrially feasible strategy to boost ester biosynthesis, offering a recyclable TL valorization approach and verifying substrate-limited esterification in solid-state Baijiu fermentation. Full article

Food waste represents not only a material and environmental problem, but also a loss of economic, social, and environmental value embedded throughout the food system. This study proposes the Circulus Valor framework as an exploratory conceptual perspective that integrates Critical Thinking, Creativity, Collaboration, and Communication into the discussion of food waste recycling and value retention. The 20-item questionnaire was organized into four a priori conceptual domains and underwent expert review by seven specialists and pilot testing with 60 participants. The pilot instrument showed satisfactory preliminary internal consistency (overall α = 0.927; domain-level α = 0.814–0.881), with corrected item–total correlations ranging from 0.41 to 0.74. The main analysis was based on 711 valid responses, including 101 respondents affiliated with the Romanian Ministry of Agriculture and Rural Development. The pooled 20-item set showed high internal consistency (α = 0.954). Creativity recorded the highest mean score (3.37), followed by Critical Thinking (3.33), Collaboration (3.19), and Communication (2.92), while the author-defined 4C Index was 3.20. Inter-domain correlations ranged from 0.63 to 0.77, indicating substantial positive association and overlap, but not factorial distinctiveness. The Circulus Valor Score (CVS = 0.64) is reported as an exploratory descriptive summary of balance among the four domain scores. The findings are perception-based and do not validate a four-factor scale, establish discriminant validity, or demonstrate causal relationships with objective food waste or value-retention outcomes. Full article

Plant regeneration demonstrates the remarkable developmental plasticity of plants, enabling tissue repair, organ formation, and adaptation to environmental challenges through cellular reprogramming and redifferentiation. This capacity underpins numerous horticultural and biotechnological applications, including grafting, micropropagation, somatic embryogenesis, organogenesis, and genetic transformation. While regeneration has traditionally been explained by the coordinated actions of auxin and cytokinin together with key developmental regulators such as WUSCHEL, BABY BOOM, and WUSCHEL-related homeobox genes, recent studies indicate that regeneration is also influenced by stress signaling, metabolic reprogramming, reactive oxygen species, and epigenetic regulation. Among these regulatory components, polyamines have emerged as important modulators of cell division, differentiation, stress responses, and morphogenic competence during in vitro regeneration. Likewise, autophagy, a conserved intracellular recycling pathway, has gained increasing attention for its role in maintaining cellular homeostasis, facilitating metabolic adaptation, and supporting developmental transitions under tissue culture conditions. This review summarizes current knowledge on the independent roles of polyamines and autophagy in plant cell reprogramming and in vitro regeneration, with particular emphasis on wound responses, somatic embryogenesis, and organogenesis. In addition, it highlights common physiological processes through which these pathways may influence regeneration and identifies the limited understanding of their potential relationship as an important direction for future research. Full article

Lead (Pb²⁺) pollution poses a severe threat to the ecological environment and human health due to its high toxicity, bioaccumulation, and refractory nature. Traditional treatment technologies for lead-contaminated wastewater, such as chemical precipitation, ion exchange, and membrane separation, often face limitations, including secondary pollution, high costs, and high energy consumption. In contrast, adsorption has emerged as a promising alternative technology with advantages such as a simple process, high efficiency at low concentrations, and renewability. Biomass-based hydrogels and their composite systems, as novel green adsorbent materials, combine the abundant functional groups of natural biomass with the structural stability, high porosity, and recoverability of hydrogels through a three-dimensional cross-linked network, offering unique advantages for lead ion adsorption. Depending on their composition, these systems range from fully biodegradable pure biopolymer networks to partly biodegradable or biomass-containing composites incorporating inorganic, carbon-based, or metal–organic framework (MOF) materials. This paper systematically reviews the latest research progress on cellulose, lignin, sodium alginate, chitosan, starch-based hydrogels, and their composite systems for lead (Pb²⁺) adsorption. First, the structural characteristics, cross-linking mechanisms, and functional modification strategies of various biomass hydrogels are introduced. Then, the adsorption mechanisms of Pb²⁺, including multiple modes of action such as coordination complexation, ion exchange, electrostatic interaction, and physical adsorption, are systematically analyzed. The adsorption performance of different material systems is compared in detail. The regeneration and recycling performance, as well as the potential practical applications, of the materials are evaluated. On this basis, the main challenges in current research are summarised: balancing adsorption capacity and mechanical strength, achieving selective adsorption in actual wastewater, improving regeneration efficiency, and optimizing costs. In addition, future development directions for biomass hydrogel adsorbent materials are discussed, including the design of multi-functional composite materials, the development of intelligent, responsive hydrogels, engineering-scale-up, and life-cycle assessment. This review aims to provide a theoretical framework and technical roadmap for the rational design of high-performance, sustainable hydrogel adsorbents and to promote their engineering application for the treatment of lead-contaminated wastewater. Full article

Problem statement: Contaminated mixed plastic waste—bearing metallic, paper, cardboard and organic residues—remains largely excluded from mechanical recycling because conventional routes require a costly, water- and energy-intensive washing–drying pretreatment. Research gap: No published study combines a fully dry, washing-free valorisation route for such waste with certified mechanical characterisation and a quantified CO₂ mass balance that explicitly credits elimination of the washing–drying stage. Methodology: This study presents DMP (Downcycled Mixed Plastic), a patented (OSIM, Romania) dry valorisation process based on continuous single-screw extrusion (D = 150 mm, L/D = 17.3), characterised through differential scanning calorimetry (DSC), certified mechanical/thermal testing at accredited Romanian laboratories, Weber-number dispersion analysis, and a process-parameter sensitivity study. Key findings: The composite exhibits certified mechanical properties (tensile strength 9.22 MPa, elongation at break 112.8%, compressive strength 14.5 MPa); composition–property analysis across four batches shows that increasing the PP weight fraction from 20 to 28 wt% raises tensile strength by 8.3% while reducing elongation by 5.2%; a computed Weber number (We = 166.7 ≫ We_crit) is consistent with fine PP-phase dispersion within the PE matrix; the sensitivity study confirms statistically robust structure–property relationships (R² = 0.93–0.98); and the CO₂ mass balance establishes a net avoidance of 3.150 t CO₂ eq per tonne of waste processed relative to conventional wet recycling. Significance: dry, washing-free processing is a technically promising pathway for valorising plastic waste streams currently considered non-recyclable, potentially reducing production cost by 60–70% relative to wet recycling, pending additional characterisation identified as priorities for future work. Full article

The HIV-1 Env glycoprotein mediates both cell-free and cell-to-cell viral transmission and represents the primary target for protective humoral immune responses. Studies examining antibody neutralization of cell-free and cell-to-cell HIV transmission have found that cell-to-cell transmission is more resistant to neutralization. This resistance may be explained in part by antigenically distinct Env populations on virions and infected cells. Cell-surface Env may be more heterogeneous due to variations in cleavage, glycosylation, and conformational state. Nevertheless, the mechanisms that maintain antigenically distinct Env populations at the cell surface and on virions remain unclear, despite virion assembly occurring at the plasma membrane. In this focused review, we consider how Env endocytosis and recycling influence Env incorporation into virions and antibody recognition. We further consider how Env cleavage may influence trafficking and endocytic fate. Given the central role of Env’s cytoplasmic tail in engaging endosomal trafficking pathways, we review emerging structural models of the CT and discuss how its organization, symmetry, and conformational flexibility may contribute to Env trafficking and intracellular sorting. We also discuss how heterogeneous Env populations may influence antibody susceptibility. Finally, we review therapeutic strategies, including combinatorial antibodies and small-molecule Env modulators, that may enhance antibody recognition of infected cells and virions. Full article

The co-contamination of aquatic environments by antibiotic residues and organic dyes poses a serious threat to ecological security and human health, underscoring the urgent need for high-efficiency, recyclable, and environmentally benign adsorbents. Chitosan, a naturally occurring alkaline polysaccharide rich in reactive functional groups, has attracted considerable attention in water treatment applications. Nevertheless, its practical use is often constrained by intrinsic limitations, including poor stability in acidic media, inadequate mechanical strength, and difficulties in solid–liquid separation. Chitosan-based hydrogels, featuring unique three-dimensional cross-linked networks, high porosity, and strong hydrophilicity, provide efficient mass-transfer pathways for macromolecular contaminants and thus offer a promising strategy to overcome the shortcomings of pristine chitosan. This review comprehensively summarizes recent advances in chitosan-based hydrogel adsorbents, with a focus on elucidating the critical structure–performance relationships that link molecular/structural design to adsorption efficacy. First, fabrication strategies are systematically reviewed, ranging from molecular-level modifications (e.g., grafting, chemical cross-linking, and interpenetrating polymer networks) to macroscopic structural engineering approaches (e.g., mechanically reinforced, magnetic, and stimuli-responsive hydrogels). Subsequently, adsorption behaviors toward representative classes of antibiotics, including tetracyclines, fluoroquinolones, and sulfonamides, are critically examined, with emphasis on the underlying mechanisms such as electrostatic interactions, hydrogen bonding, π–π stacking, and pore-filling effects. In addition, the removal performance of chitosan-based hydrogels for organic dyes with varying charge characteristics is summarized, together with an analysis of how environmental factors (e.g., pH and ionic strength) influence adsorption kinetics and thermodynamics. Finally, key challenges related to mechanical robustness, selective adsorption, and recyclability are discussed, and future perspectives are proposed for the development of multifunctional, synergistic, and intelligent, environmentally responsive chitosan-based hydrogel materials. This review aims to provide systematic insights and guidance for the rational design of advanced hydrogel adsorbents for the treatment of complex wastewater. Full article

This study was conducted to determine the optimal mineralization enhancement period for recycled aggregates, and to elucidate the mechanisms underlying the mineralization enhancement of recycled aggregates and the self-healing of concrete cracks. Microbial-induced calcium carbonate precipitation enables the self-healing of concrete cracks: microbial carriers can effectively increase the survival rate of microorganisms within the concrete matrix, thereby enhancing the self-healing performance of the concrete. However, current carriers suffer from poor mechanical properties, poor compatibility with cement-based materials, and high costs. This study proposed a crack-self-healing concrete based on a mixed culture of microorganisms immobilized in recycled aggregate, and investigated the effects of the time of recycled aggregate incorporation on the concrete’s compressive strength and self-healing performance. The results showed that the optimal adsorption and incubation times for the recycled aggregates were 15 min and 9 days, respectively. Following mineralization and reinforcement, the water absorption and crushing index of the recycled aggregates was 11.4% and 20.4%, respectively. Moreover, the precipitates at the concrete cracks were in the form of regular cubes and clusters, and the crystals were calcite and aragonite. Small amounts of phosphorus were detected, originating from extracellular polymers produced by microbial metabolism, indicating that the organic matrix was involved in the crystal nucleation and growth processes. The compressive strength of the concrete increased by 35%. After repair and curing, the crack healing rate of the concrete reinforced with microorganisms immobilized on the recycled aggregates reached 70%. Full article

Currently, the significance of oil refinery industry is unquestionable because of the increasing demand for petrochemical products, such as fuels, monomers, and organic chemicals. Despite this, apart from high greenhouse gas emissions, numerous oil and natural gas refining processes are distinctly associated with the generation of a considerable amount of Oil Refinery Wastes (ORWs) in different forms, which need proper disposal and valorization. Nonetheless, at present, solid ORWs are mainly sent to landfills. Such a procedure, apart from high disposal costs, results in significant environmental pollution related to the release of chemical contaminants to soil and water environment. Consequently, these pollutants might poison natural flora and digestive systems of animals, thereby contributing to the general degradation of useful land and a serious health risk. To cope with that issue, ORW recycling in cement-based materials might be considered a reliable course of action, as the hardened concrete is capable to bind contaminants that ORW comprises. This article focuses on actual literature knowledge, limitations, and chances in the scope of a comprehensive approach to sustainable management of ORWs through their utilization in cementitious composites. The special emphasis was placed on presenting the impact provided by the addition of ORWs on the numerous performances of cementitious mixes and hardened concrete. The environmental and economic aspects were also discussed, particularly in the scope of CO₂ emission reductions and cost savings. Finally, the proposal for future tests, including investigating the correlation between valorization of ORWs and toxicity of ORW-blended composites, were proposed. Full article

The accelerating transition toward renewable electricity generation has elevated grid-scale electrochemical energy storage from an ancillary grid service to a foundational infrastructure requirement. This review provides a comprehensive account of rechargeable battery technologies for stationary grid applications, spanning advanced lithium-ion systems, sodium-ion and post-lithium multivalent chemistries, vanadium and organic flow batteries, solid-state architectures, and high-energy-density future systems such as lithium-sulfur and metal-air cells. The techno-economic context of grid-scale storage is systematically examined, including performance metrics, market drivers, and regulatory frameworks. Each battery chemistry is analyzed with respect to electrochemical mechanism, cycle life, energy density, safety profile, material availability, and commercial readiness. Non-electrochemical storage technologies are discussed as system-level alternatives. Battery safety engineering, thermal management system design, thermal runaway mechanisms and prevention, and failure containment strategies are examined in depth, followed by analysis of critical material supply-chain vulnerabilities, life-cycle assessment, and recycling pathways. The expanding role of artificial intelligence, machine learning, and digital twin frameworks in optimizing performance and enabling predictive maintenance is reviewed. Key challenges, including material bottlenecks, manufacturing scalability, long-duration storage gaps, and the absence of harmonized performance standards, are identified, and the review concludes with a techno-economic roadmap toward cost-competitive, resilient, and low-carbon grid storage. Full article