Search Results (1,417)

Rice husk, an abundant agro-industrial by-product rich in SiO₂, represents a promising precursor for the sustainable synthesis of zeolites. In this study, rice husk ash was used to synthesize faujasite-type X and faujasite-type Y, and their performance for Hg²⁺ removal from aqueous solutions was comparatively evaluated. X-ray diffraction confirmed the successful formation of the faujasite structures, while physicochemical characterization revealed differences in pore structure and surface chemistry. FAU-type X exhibited higher Hg²⁺ removal than FAU-type Y, consistent with the combined influence of its lower Si/Al ratio, higher framework charge density and ion-exchange capacity, as well as its larger pore volume and average pore diameter. Based on its higher Hg²⁺ removal, FAU-type X was selected for a comprehensive evaluation of its adsorption performance and applicability under environmentally relevant conditions. The pseudo-second-order model best described adsorption kinetics for both zeolites, whereas thermodynamic analyses indicated that the adsorption process was spontaneous and endothermic. Optimal adsorption conditions for FAU-type X were achieved at pH 6.8, using an adsorbent dosage of 0.75 g L⁻¹, a contact time of 24 h, and an initial Hg²⁺ concentration of 1 mg L⁻¹. Equilibrium data were best fitted by the Sips isotherm model, indicating adsorption on a heterogeneous surface with a maximum adsorption capacity of 83.14 mg g⁻¹. FAU-type X retained appreciable adsorption performance after four regeneration cycles, although Hg²⁺ removal efficiency decreased in Caquetá River water because of competition from coexisting metal ions. To assess the environmental implications of the treated water beyond Hg²⁺ removal efficiency, ecotoxicological assays demonstrated the sensitivity of Daphnia magna to residual Hg²⁺ concentrations, whereas reductions in Escherichia coliforms were mainly attributed to the adsorption process. In addition, Lactuca sativa seedlings exhibited approximately 50% inhibition of elongation after treatment. Overall, these findings demonstrate the potential of rice husk-derived faujasite-type X as a sustainable adsorbent for Hg²⁺ removal, while highlighting the need for complementary treatment strategies to ensure the environmentally safe discharge of water and its agricultural reuse. Full article

Widespread polyethylene (PE) mulch film application has caused severe farmland plastic pollution and greenhouse gas emissions. To identify low-carbon end-of-life pathways for waste agricultural mulch film, this study established a full life-cycle carbon footprint model comparing three treatment scenarios—incineration, mechanical regranulation, and pyrolysis, each coupled with residue landfilling—under two accounting conditions: with and without carbon-compensation credits from by-product substitution. Using 1 t of waste film as the functional unit and an 8 km² farmland plot (110.4 t of applied film) as the reference scenario, cradle-to-grave emissions were quantified. Without compensation, regranulation delivers the lowest emissions (519.17 t CO₂ eq), 12.02 t CO₂ eq below pyrolysis. With compensation credits, pyrolysis achieves the lowest net emission (247.82 t CO₂ eq, 248.10 t CO₂ eq less than regranulation), but this advantage arises from avoided emissions of product substitution rather than lower direct emissions. The per-tonne carbon footprint ranks pyrolysis (2.24 t CO₂ eq) < regranulation (4.49 t CO₂ eq) < incineration (5.15 t CO₂ eq). A proposed 5400 t/year pyrolysis facility yields an annual net carbon reduction of 1082.16 t CO₂ eq. These results inform differentiated disposal strategies for major mulch-film-covering provinces. Full article

Pomegranate is increasingly being recognized as a versatile source of bioactive compounds with antimicrobial, antioxidant, anti-inflammatory, and microbiota-modulating potential. Beyond the edible arils and juice, peel, seeds, leaves, flowers, and other agro-industrial by-products are rich in ellagitannins, particularly punicalagins, as well as ellagic acid, gallic acid, flavonoids, anthocyanins, fatty acids, and related phytochemicals. Their recovery depends strongly on plant fraction, cultivar, solvent, and extraction technology, including conventional hydroalcoholic extraction, ultrasound- and microwave-assisted processes, high-pressure treatments, and enzyme-assisted methods. Pomegranate-derived preparations exhibit activity against Gram-positive and Gram-negative bacteria, fungi, multidrug-resistant pathogens, and microbial biofilms, while selected compounds may enhance the efficacy of conventional antimicrobials. Emerging evidence also indicates bidirectional interactions with microbial communities, including microbial biotransformation of ellagitannins into urolithins and modulation of beneficial taxa and microbial metabolites. This narrative review integrates agronomic and phytochemical diversity, extraction and standardization strategies, mechanisms of antimicrobial action, synergistic interactions, microbiota-related effects, and applications in food preservation, biomedicine, animal nutrition, agriculture, and environmental sustainability. Key translational limitations include compositional variability, methodological heterogeneity, insufficient standardization, limited in vivo validation, and scarce evidence from realistic application models and clinical studies. Addressing these gaps is essential for developing safe, reproducible, and scalable pomegranate-derived preparations. Full article

The application of exogenous nutrient bags (ENBs) is critical for achieving high yields in morel mushroom cultivation; however, the high cost and lack of locally adapted formulations have become major constraints for the sustainable expansion of this industry. This study aimed to evaluate the effects of ten treatments, including a conventional formulation control, incorporating locally available agricultural by-products (rapeseed straw, organic fertilizer, alfalfa, and oats), on soil fertility, enzyme activity, microbial community structure, and ultimately the yield and quality of cultivated Morchella sextelata in Jianzha County, Qinghai. A randomized complete block design was established, and soil physicochemical properties, microbial biomass carbon/nitrogen/phosphorus (MBC/MBN/MBP), and enzyme activities (urease, phosphatase, and catalase) were measured at 38, 62, and 137 days post-application, while bacterial and fungal community compositions were characterized via high-throughput sequencing of 16S rRNA and ITS2 genes. Our results demonstrated that the wa-60 treatment (30% wheat + 60% alfalfa) outperformed all the other formulations, delivering the highest yield (1.32 ± 0.08 kg/m²) and a 28.6% increase over the control (1.03 ± 0.06 kg/m²; p < 0.01), while maintaining a high total amino acid content (19.8 g/100 g). Soil analysis revealed that wa-60 notably enhanced urease activity (peaking at 85 µg/g/h at day 137) and alkaline phosphatase activity (322.55 µg/g/h), alongside significant increases in MBC and MBN. Microbiome profiling further demonstrated that wa-60 selectively increased the relative abundance of various taxa, particularly the bacterial phylum Bacteroidota and the fungal phylum Mortierellomycota. Correlation analyses indicated strong positive associations among these enriched taxa (primarily at the genus level), enhanced enzyme activities, and improved soil nutrient availability. Collectively, these findings establish that the wa-60 formulation, leveraging locally sourced alfalfa, represents a cost-effective and high-performance strategy for morel cultivation in the Qinghai Plateau, providing a microbial–ecological basis for optimizing ENB design and offering a practical pathway for recycling agricultural waste in edible mushroom production. Full article

Next-generation waste degradation and valorization technologies are increasingly developed as integrated platforms for pollutant removal, resource recovery, and circular manufacturing. This review critically evaluates degradation and valorization routes for liquid, organic solid, and inorganic/electronic waste streams from an engineering perspective. For liquid waste, advanced oxidation processes, photocatalysis, electrochemical oxidation, plasma treatment, and hybrid systems are assessed with emphasis on radical utilization, photon and electron efficiency, catalyst stability, byproduct formation, and reactor hydrodynamics. For organic solid waste, biological, thermochemical, catalytic, enzymatic, and mechanical pathways are compared for agricultural residues, textile waste, and industrial polymers, including fermentation, pyrolysis, hydrogenolysis, solvolysis, enzymatic depolymerization, and mechanical recycling. Their practical viability depends strongly on feed purity, product selectivity, monomer or fuel recovery, and the energy and separation requirements of downstream processing. For inorganic and electronic waste, hydrometallurgical, pyrometallurgical, biohydrometallurgical, and physical separation routes are examined for the recovery of critical metals, mineral phases, and non-metallic fractions. Industrially mature integrated flowsheets generally offer greater feed tolerance, whereas emerging selective routes provide improved recovery potential but remain constrained by reagent consumption, reaction rate, and scale. Across all waste classes, the review identifies reactor design, process intensification, reaction–separation integration, techno-economic analysis, and life-cycle assessment as essential tools for translating laboratory performance into scalable, economically competitive, and environmentally sustainable processes. Full article

Fermented foods and beverages represent a cornerstone of Nigerian food culture, yet their scientific documentation remains fragmented, and their potential within global bioeconomy frameworks is largely unrealised. This review addresses two interrelated gaps: the absence of a comprehensive ethnogeographic analysis of Nigerian fermented foods that integrates ecological, cultural, and agricultural drivers of regional diversity, and the limited examination of these foods as models for circular bioeconomy development. Using a narrative synthesis of peer-reviewed literature spanning 1986–2025, we systematically map the distribution of fermented tuber, cereal, legume, dairy, and fruit products across Nigeria’s major geopolitical zones, demonstrating that agroecological endowment, ethnic composition, trade routes, and cross-cultural interactions shape regional variation. Beyond their socio-cultural significance, Nigerian fermented foods contribute meaningfully to food security by extending shelf life, enhancing nutrient bioavailability, and reducing post-harvest losses. This review further positions ogi (fermented maize gruel) and garri (fermented cassava granules) as model systems for circular bioeconomy integration, demonstrating how by-product valorisation can generate value-added outputs, including animal feed, bioethanol, biodegradable packaging, and organic acids. Key challenges, including food safety deficits, absence of standardised production protocols, and limited regulatory frameworks, are critically assessed. Three priority research directions are identified: metagenomics-based microbiome profiling, development of culturally appropriate starter cultures, and formulation of gender-responsive regulatory instruments. Nigerian fermented foods, properly documented and integrated into innovation systems, represent an underutilised asset for sustainable food system transformation in Sub-Saharan Africa. Full article

Growing global challenges have made it imperative to evaluate economic activities not only in terms of economic growth but also from the perspectives of environmental and social well-being. Within this context, Women’s Production and Business Cooperatives have emerged as critical collective initiatives that support local development. In this study, “Women’s Production and Business Cooperatives” refer to cooperatives established and predominantly managed by women to collectively engage in the production and commercialization of goods and services, generate income and employment opportunities for their members, and promote women’s economic and social empowerment. Hereafter, these organizations are referred to as “women’s cooperatives.” However, studies that comprehensively examine the sustainability practices of women’s cooperatives through the framework of Elkington’s Triple Bottom Line (economic, social, and environmental sustainability) remain limited. From the perspective of Stakeholder Theory, cooperatives are regarded as organizations that extend beyond the pursuit of economic profit by creating value for both internal and external stakeholders, including women, local communities, the environment, consumers, and public institutions. Accordingly, this study aims to provide an in-depth examination of the sustainability practices adopted by women’s cooperatives within these three dimensions, as well as to identify the challenges they encounter. This study adopted a qualitative research design, utilizing in-depth interviews with seven presidents and managers representing women’s cooperatives. The findings suggest that zero-waste practices, the adoption of circular economy principles, and the transition toward green agriculture constitute the primary sustainability initiatives, whereas high technology and packaging costs, together with insufficient institutional collaboration, represent the major challenges to the environmental sustainability. Within the economic sustainability dimension, the findings indicate that the participating cooperatives have increasingly shifted toward industrial production standards, value-added by-products, and business-to-business (B2B) marketing strategies. Nevertheless, rising input and logistics costs, together with unfair competition, continue to pose significant challenges. As relates to social sustainability, the findings highlight intergenerational transmission of cultural heritage, psychosocial recovery, efforts to challenge social prejudice, inter-cooperative solidarity, and the allocation of resources for social benefit, including scholarship support. Overall, the findings reveal that these cooperatives make meaningful contributions to multidimensional sustainability and stakeholder well-being, thereby providing valuable empirical insights into the sustainability literature. Full article

The utilization of protein-rich agricultural by-products offers a sustainable strategy for developing plant-based meat analogs. This study investigated the effects of cold-pressed hemp seed cake (HSC) incorporation at levels of 0–20% on the pasting, thermal–rheological, textural, and structural properties of high-moisture meat analogs produced by extrusion. Increasing HSC incorporation significantly reduced peak viscosity, indicating altered starch–protein–fiber interactions within the blends. During temperature-sweep measurements, all formulations exhibited elastic-dominant behavior, with the storage modulus remaining higher than the loss modulus throughout heating and cooling. Although the initial viscoelastic moduli decreased with increasing HSC content, the final moduli after cooling were comparable to those of the control. Incorporation of 15% and 20% HSC significantly decreased hardness from 44.02 to 38.88 N and chewiness from 1730.20 to 1517.31 g, whereas springiness, cohesiveness, and the hardness degradation ratio remained largely unchanged. Fibrous structures were maintained in all formulations, while cutting strength tended to increase and the texturization degree numerically increased from 1.04 to 1.15 at 20% HSC. These findings demonstrate that HSC can replace up to 20% of the conventional protein–starch blend while maintaining thermal viscoelasticity and anisotropic fibrous structure, although producing a moderately softer high-moisture meat analog. Full article

Global plastic production is expected to continue rising in the next few decades, with packaging accounting for roughly one quarter of the total volume of plastic and intensifying interest in biodegradable alternatives such as polylactic acid (PLA). One approach towards bioplastic production is lactic acid fermentation. Lactic acid (LA) can be produced from waste and by-products, such as food and agricultural waste, and then polymerised into PLA. This review provides an overview of LA production from waste-derived feedstocks, covering substrate composition, pretreatment and hydrolysis strategies, fermentation modes, and downstream operations, and highlights key performance indicators (yield, final LA concentration, and volumetric productivity). This review examines technological bottlenecks associated with waste heterogeneity, mixed sugar utilisation, inhibitor formation, pH and temperature control, contamination risks, high cost, and complexity of LA recovery and purification. Recent advances in pre-treatment, robust or engineered microbial strains, mixed microbial cultures, process integration, and intensified downstream schemes are also discussed to increase productivity and purity while reducing energy and chemical inputs. Finally, techno-economic assessment studies on waste-based PLA are synthesised, showing that both economic and environmental performance depend on feedstock logistics, process configuration, and end-of-life options for PLA products. Full article

Wheat dust, an underutilized agro-industrial by-product, is rich in nutrients and may serve as a sustainable soil amendment. This study evaluated its effects on wheat (Triticum durum L.) growth, nitrogen metabolism, and drought tolerance. Two greenhouse experiments were conducted. First, a dose–response trial (0, 2, 5, 10, 20% w/w) assessed biomass, chlorophyll content (SPAD), and expression of nitrogen-related genes (NR, NRT1, NRT2, GS2). Second, a factorial experiment (0, 10, 20% × well-watered or 50% water capacity) examined growth, yield components, oxidative stress markers (MDA), antioxidant enzymes, soil enzymatic activities, and multivariate responses. Wheat dust elicited concentration-dependent, context-specific effects. Under well-watered conditions, 10% was optimal, increasing shoot biomass (+39%) and chlorophyll (+10–15%), accompanied by upregulation of NR, NRT1, and NRT2, indicating enhanced nitrogen acquisition. Under drought, 20% produced the strongest effects: biomass increased by +313%, seed number per spike by +3900%, and seed weight per spike by +1650% relative to the stressed control. Lipid peroxidation declined by 83%, while chlorophyll increased by +215%, reflecting strong protection of membrane integrity and photosynthetic capacity. Soil biological activity was markedly stimulated at 20% under drought, with FDA hydrolysis (+1320%) and protease activity (+8250%) indicating enhanced microbial functioning and nitrogen cycling. Principal component analysis confirmed a systemic shift from stress-dominated profiles in controls to growth- and metabolism-oriented profiles at 20%, with convergence of stressed and non-stressed plants. Thus, wheat dust improves productivity at moderate doses and confers pronounced drought resilience at higher rates, supporting its valorization within climate-resilient, circular agricultural systems. Full article

The transition from conventional silica nanoparticle (SiNP) production based on purified alkoxysilanes and high-temperature flame hydrolysis of silicon tetrachloride to renewable and waste-derived silicon resources requires more than precursor substitution. It requires a mechanistic understanding of how feedstock mineralogy, silicon speciation, impurity chemistry, and processing history propagate through dissolution, nucleation, condensation, gelation, aging, drying, and pore evolution to determine material performance, environmental burden, and manufacturing feasibility. Although previous reviews have established the technical feasibility of producing silica from secondary resources, their predominant organization by feedstock, synthesis route, or application provides limited ability to explain why nominally similar processes generate materials with markedly different structural and functional properties. This review addresses these through a resource-pull, feedstock-to-function framework that links resource chemistry and process design to critical material attributes, application-specific specifications, sustainability, and scale-up requirements. Agricultural residues, industrial by-products, geothermal resources, waste glass, and fluorosilicate streams are critically compared according to silicon form and phase, reactivity, impurity profile, compositional variability, purification demand, and attainable product quality. Particular attention is given to waste-derived alkaline silicate systems, in which molecular, oligomeric, and colloidal silica coexist and therefore require characterization beyond bulk SiO₂ concentration. Established and emerging processing strategies, including controlled combustion and alkaline extraction, alkali fusion, ambient-pressure drying, microwave and mechanochemical activation, biogenic and biomimetic templating, and continuous processing, are evaluated according to their mechanistic effects, technological maturity, structural control, and demands for energy, reagents, water, solvents, effluent treatment, and capital. Across these routes, gelation and aging emerge as critical transfer stages through which feedstock composition is translated into network connectivity, pore architecture, shrinkage behavior, and ultimately functional performance. Evidence from secondary-source aerogels further shows that properly controlled waste-derived systems can attain BET surface areas of approximately 350–500 m² g⁻¹, within the textural range of many alkoxide-derived materials, indicating that feedstock variability, impurity management, and process control are more important constraints than an inherently lower performance ceiling. On this basis, this review proposes a minimum evidence framework comprising feedstock traceability, intermediate-speciation and colloidal characterization, silicon mass balance, gelation and aging metrics, application-specific qualification criteria, performance-normalized life cycle and techno-economic assessment, process analytical control, and staged pilot validation. Collectively, these principles provide a mechanistically grounded basis for moving sustainable silica synthesis beyond isolated proof-of-concept demonstrations toward reproducible, scalable, application-matched, and commercially credible manufacturing platforms. Full article

In the context of the global shift toward sustainable energy systems and circular economy strategies, anaerobic digestion is a well-established biotechnology for the valorisation of organic residues, the production of biogas as a renewable energy carrier, and the generation of nutrient-rich digestate. This study aimed to evaluate the stability and methane yield of a two-stage co-digestion process using a substrate mixture developed based on the actual feedstock composition of a full-scale agricultural biogas plant. The daily feed mixture consisted of maize silage (8.2%), sugar beet pulp (4.9%), cellulose pulp (6.6%), distillery stillage (38.6%), corn syrup (6.4%), cattle slurry (22.5%) and sterilised animal by-products (12.8%). Digestate was recirculated separately as part of the reactor operation. Laboratory-scale experiments were conducted in a two-stage anaerobic digestion system operated at 42 °C and 50 °C. The physicochemical properties of the substrates and digestate were determined, biogas quantity and composition were monitored, and the microbial community structure was assessed using 16S rRNA gene amplicon sequencing. The process remained stable throughout the experimental period, with pH values ranging from 8.23 to 8.53, alkalinity between 2600 and 2940 mg CaCO₃/dm³, and a VFAs/alkalinity ratio of 0.17–0.93. Despite ammonium nitrogen concentrations reaching 4346 mg N-NH₄⁺/L, no clear concurrent reduction in gas or methane production was observed. Methane accounted for approximately 70–80% of the biogas produced. The overall specific methane yield reached 346.4 NL CH₄ kg⁻¹ VS added. 16S rRNA gene amplicon sequencing revealed a diverse microbial community containing taxa previously associated with hydrolysis, fermentation and syntrophic interactions, including Proteiniphilum and Syntrophaceticus. The results demonstrate stable process performance and methane production in this site-specific laboratory-scale case study based on the feedstock composition and process configuration of a full-scale agricultural biogas plant. Full article

Agricultural by-products and Chinese medicine crop residues, as non-traditional animal feed, have great potential to alleviate the scarcity of traditional feed and reduce the environmental burden. In this study, the effects of adding fermented ginseng by-products to the diet on growth performance, meat quality, flavor characteristics and metabolism of Hongyu roosters were evaluated. A total of 100 Hongyu roosters were randomly assigned to either a control (Con) group fed a basal diet or a fermented ginseng by-products (Fe) group fed a basal diet supplemented with 3% fermented ginseng by-products, with five replicates per group, for 100 days. The results demonstrated that the fermented diet significantly enhanced final body weight and average daily gain (ADG) while reducing the feed conversion ratio (FCR) (p < 0.05). The percentages of breast and thigh muscles and breast muscle fiber diameter were significantly increased. The results also exhibited enhanced water-holding capacity, coupled with significantly decreased shear force and drip loss (p < 0.05). Electronic nose and tongue analyses confirmed enriched meat aroma and optimized taste profiles, which aligned with elevated levels of flavor-precursor amino acids and essential polyunsaturated fatty acids. Serum metabolomics found purine metabolism and the biosynthesis of unsaturated fatty acids to be pivotal pathways. Metabolites related to nucleotide and lipid metabolism were regulated. In conclusion, fermented ginseng by-products serve as an effective functional feed to improve poultry growth performance and meat quality. Full article

Wood vinegar (WV), also known as pyroligneous acid, is the aqueous condensate produced during lignocellulosic biomass pyrolysis, generated alongside biochar and non-condensable gases. In forest biorefineries, it represents a promising value-added coproduct capable of transforming forestry and agroforestry residues into a multifunctional bioproduct. Its composition, dominated by water, organic acids, phenolic compounds, aldehydes, and ketones, confers antimicrobial, antioxidant, biostimulant, herbicidal, and preservative properties. This review critically examines WV production, chemical composition, purification strategies, mechanisms of action, and applications, explicitly distinguishing evidence-based uses from prospective ones. Current evidence supports applications in agriculture, wood preservation, environmental management, and forestry, including forest nursery production and clonal propagation of Eucalyptus and Pinus. However, the literature remains fragmented by compositional variability, non-standardized terminology, limited mechanistic understanding, and scarce long-term toxicological and techno-economic assessments. WV holds significant potential for sustainable biomass valorization and circular bioeconomy strategies. Realizing this potential requires harmonized analytical protocols, standardized formulations, rigorous mechanistic studies, life-cycle assessments, and regulatory frameworks that support the transition of this heterogeneous pyrolysis byproduct into a reliable commodity within integrated forest biorefineries. Full article

The growing focus on environmental sustainability in construction has driven advancements in the design and production of masonry materials, including bricks and concrete blocks. A major development is the incorporation of agricultural and industrial waste, such as fly ash, rice straw ash, bagasse ash, and other by-products, to reduce dependence on non-renewable resources and lower the carbon footprint of traditional manufacturing processes. This systematic review examines the potential of waste materials in masonry unit production by analysing Scopus-indexed studies published between 2015 and 2025. After screening, 30 studies were selected, covering fired bricks, unfired bricks, and concrete blocks, with emphasis on physical, mechanical, thermal, and durability properties. The findings show that industrial wastes typically improve mechanical strength through pozzolanic reactions, while agricultural wastes contribute to lower density and improved thermal insulation. However, performance depends on waste type, replacement level, and production conditions. Optimal incorporation levels are generally below 20%. Despite promising results, challenges remain, including the absence of standardised testing methods, limited durability evaluations, and insufficient evidence for large-scale industrial adoption. This review highlights current research trends and future opportunities for integrating waste materials into sustainable construction products. Full article