Search Results (463)

Volatile organic compounds (VOCs) are major contributors to air pollution and pose significant risks to both environmental quality and human health. Biochar-based adsorption technology is an efficient and sustainable approach to VOCs removal. Herein, hybrid biochar was prepared from corn stover and municipal sewage sludge using the water vapor activation method, and its physicochemical characteristics and adsorption mechanisms for typical volatile organic compounds commonly produced during biomass-derived energy generation—such as methylbenzene, isopentane, and ethylene—were systematically investigated. The results show that hybrid biochar significantly outperformed single-source biochar, with its ability to adsorb methylbenzene, isopentane, and ethylene exceeding that of pure sludge biochar by 112.21%, 74.53%, and 66.72%, respectively, and surpassing pure corn stover biochar by 74.25%, 62.98%, and 55.25%, respectively. Competitive adsorption analysis indicated that the interaction strength between VOC molecules and the steam-treated hybrid carbon material was associated with their boiling points; compounds with higher boiling points tended to exhibit stronger affinity. This work provides an integrated waste utilization and pollution control strategy for VOCs removal. Full article

The development of sustainable and efficient plant growth substrates is crucial for modern agriculture. This study assessed the potential of plant pellets formulated from various lignocellulosic residues, either with or without bamboo biochar (BB-char) and arbuscular mycorrhizal fungi (AMF), to support seed germination and early seedling growth. Four types of residues, including coconut coir (CO), corn cob (CC), leaves from the genus Dipterocarpus (DL), and teak leaves (TL), were combined with soil and paper waste to produce eight pellet formulations, with commercial peat pellets serving as a control. Chemical analyses revealed significant variation among the pellet types, with pH values ranging from 6.40 to 7.65, electrical conductivity (EC) from 3.64 to 11.62 mS cm⁻¹, and differences in organic matter, carbon, and nutrient contents [nitrogen (N), phosphorus (P), potassium (K)], reflecting the influence of residue type and the addition of BB-char and AMF. Phytotoxicity screening using aqueous extracts demonstrated species-specific responses, with cucumber exhibiting high tolerance across treatments, whereas chili seeds were more sensitive. Final germination percentage (FGP) and seedling growth assays in greenhouse conditions showed that pellets derived from CC and CO, particularly when combined with BB-char and AMF (T6 and T7), enhanced shoot and root development in carrot, chili, cucumber, and tomato, approaching the performance of commercial peat pellets. In contrast, DL- and TL-based pellets resulted in lower germination and growth. These findings indicate that both the physicochemical properties of lignocellulosic wastes and the combination of BB-char and AMF are important factors influencing pellet efficacy, highlighting the potential of CC- and CO-based pellets as sustainable peat alternatives for early-stage plant cultivation. Full article

Recycled polypropylene (rPP) biocomposites represent a convergent strategy for plastic waste valorization and agro-industrial residue reutilization. This study quantifies tensile, flexural, and compressive performance (ASTM D638, D790, D695) of rPP biocomposites incorporating raw corn stover (Zea mays), banana pseudostem (Musa spp.), and barley residue (Hordeum vulgare) fibers at 10, 20, and 30 wt%, processed by single-screw extrusion and compression molding without compatibilizer. Two-way ANOVA with Tukey HSD post hoc analysis (α = 0.05) evaluated effects of fiber type and concentration. Tensile strength declined monotonically across all systems, from 24.9 MPa (neat rPP) to 7.9 MPa at 30 wt% banana fiber. Corn fiber exhibited exceptional tensile concentration stability (only −11% across the full range) and the best flexural retention at 10 wt% (36.6 MPa, 79% of neat rPP). A performance plateau was identified at 20 wt% under both tensile and flexural loading, beyond which further addition produced no significant reduction. Under compression, fiber type exerted its largest statistical effect (F = 81.231), all three systems were mutually distinguishable, and no plateau was observed. These results establish a loading-mode-resolved mechanical baseline for uncompatibilized rPP biocomposites, with corn fiber at 10–20 wt% as the most versatile formulation across all loading modes. Full article

The growing demand for sustainable and functional textiles has prompted exploration of novel natural fibers from agricultural by-products. This study investigates the feasibility of utilizing corn silk fibers, an abundant agro-waste from corn processing, as a blend component with cotton for yarn and knitted product development. Corn silk fibers were blended with cotton to produce ring-spun yarns, which exhibited tenacity, elongation, and hairiness comparable to pure cotton yarns. The tenacity and elongation of the cotton yarn were 16 cN/Tex and 5.46%, while those of cotton–corn silk yarns were 14 cN/tex and 4.98%, respectively. However, the unevenness (U%) of the cotton–corn silk yarn was 14.83% while that of the cotton control yarn was 10.06%. These blended yarns were successfully knitted into socks. The resulting socks demonstrated satisfactory performance in abrasion resistance, absorbency, vertical wicking, color fastness to washing, and moisture content, comparable to pure cotton socks, indicating viable processability and dyeability. The abrasion tests of the socks developed from both the yarns showed no thinning or hole formation until 10,000 abrasion cycles. This work establishes the technical feasibility of corn silk–cotton blends and highlights their potential for future research into medicinal or functional textile applications, such as antibacterial or anti-odor properties. Full article

This review evaluates pretreatment strategies for blending the organic fraction of municipal solid waste (OFMSW) with agricultural residues to recover fermentable sugars. Three mechanistic benefits have been hypothesized for such blends: ash-mineral pH buffering, endogenous protein reduction of non-productive cellulase–lignin binding, and inhibitor dilution. These mechanisms are inferred from analogous lignocellulosic systems rather than measured directly in OFMSW–agricultural residue combinations, and their translation into saccharification gains remains substrate- and pretreatment-specific. A synergy index framework with a four-tier classification (true synergy, additive, substitution, and process complementarity) is applied to reclassify the available evidence, alongside an assessment of pretreatment chemistry, enzymatic hydrolysis outcomes, and techno-economic feasibility. Integrated sequential pretreatment, particularly acid-catalyzed steam explosion and deacetylation with mechanical refining, proved most robust for heterogeneous feeds. The strongest Tier I synergy is found for SO₂-catalyzed steam explosion of hybrid poplar–wheat straw (SI 1.29–1.33; 22% monomeric sugar gain). OFMSW combined with organosolv beechwood cellulose at 35–45% OFMSW reached 58–68% saccharification (44–46 g sugar L⁻¹), a Tier III–IV outcome. Matched-control saccharification data for OFMSW–agricultural residue blends specifically have not been reported. Co-processing corn stover with wet organic waste reduced CO₂ mitigation cost from $236 to $67 per ton CO₂-eq under bio-CNG upgrading. Formal synergy quantification, blend-specific inhibitor profiling, and high-solids process intensification are the central prerequisites for commercial translation. Full article

The pavement surface temperatures in Iraq are remarkably high, causing the asphalt to deteriorate quickly, shortening its service life. While a large amount of corn husk, an agricultural waste, is available for use as an asphalt modifier, researchers have not yet fully investigated this option. In this study, the use of corn husk fiber powder (CHFP) as a long-term modifier for asphalt binders and mixtures that are exposed to high-temperature conditions is evaluated. CHFP was mixed into a 40–50 penetration grade asphalt binder at concentrations ranging from 0.0% to 0.6% by weight. Performance was assessed using laboratory tests such as penetration, softening point, rotating viscosity, dynamic shear rheometer (DSR), aging (RTFOT and PAV), and wheel tracking. The findings revealed that CHFP greatly lowers penetration while increasing the softening point, indicating increased stiffness and high-temperature stability. Rheological research showed an increase in the rutting parameter (G*/sinδ) and viscosity, as well as reduced temperature susceptibility. At the mixed level, CHFP reduced rut depth while improving dynamic stability, indicating increased resistance to permanent deformation. The best performance was obtained at 0.3% CHFP, after which, improvements decreased due to probable dispersion constraints. The performance improvement is related to the creation of a reinforcing fiber network and the absorption of light asphalt components. Overall, CHFP is a promising, environmentally friendly and cost-effective addition for increasing asphalt pavement performance and promoting sustainable waste management. Full article

Corn husk, a prevalent agricultural byproduct, remains an underutilized source of bioactive compounds. This study investigated the influence of extraction solvents (water, 50% ethanol, and 95% ethanol) and techniques (maceration, reflux, ultrasound-assisted extraction) on the phytochemical profiles and biological activities of corn husk. The results revealed that water extraction produced the highest total phenolic content, whereas 95% ethanol extraction yielded the greatest total flavonoid content and the most potent antioxidant activity in DPPH testing. In contrast, ultrasound-assisted water extraction exhibited the most potent nitric oxide inhibition (94.62 ± 2.13%) and tyrosinase inhibition (IC₅₀ = 7.54 ± 0.27 mg/mL), indicating anti-inflammatory and skin-lightening potential. This extract showed anti-collagenase activity (91.49 ± 4.01%), outperforming ascorbic acid (29.79 ± 1.00%) and EGCG (82.27 ± 1.00%), though its anti-hyaluronidase activity was limited. Cytotoxicity testing revealed cytotoxicity at 10 mg/mL, while the HET-CAM assay confirmed non-irritation at the same level. These findings underscore that ultrasound-assisted water extraction is a safe and successful technique for obtaining bioactive-rich extracts. This study supports the transition of corn husk from agricultural waste to a high-value, safe, and multifunctional natural ingredient for the cosmetic, pharmaceutical, and functional food industries. Full article

This study explores the possibility of making cardboard and molded egg carton packaging from corn residues and common reed as alternatives to wood-based pulp. Six formulations were made: corn husks (CHs), corn leaves (CLs), corn leaves (35%) plus corn husks (30%) and a corn blend (15%) of wollastonite (CaSiO₃) (CH + CL + W), a corn blend (CH + CL: husks 60%, leaves 40%), mixed corn waste (MCW) and shredded common reed (SR). Optical microscopy was used to evaluate the fiber morphology, including the calculation of the flexibility coefficient, the cell wall rigidity and the Runkel ratio, for raw materials and fiber after alkaline hydrolysis and casting of egg cartons in silicone molds. The grammage, burst strength and index, folding endurance, thickness and moisture content were measured in the cardboard samples, while warping, compressive deformation, moisture and ink absorption were measured in the egg cartons. The flexibility coefficient of the common reed fibers (64.5%) was better than that of the corn fibers (23.6%), and so was the Runkel ratio (0.86 vs. 1.2). In the case of cardboard formulations, the maximum burst strength (462.4 kPa) and the maximum burst index (3.0 kPa·g/m²) values were obtained with the MCW formulation, and the highest folding endurance (42 and 38 double folds) was obtained with the CH and SR formulations, respectively. The addition of wollastonite improved folding endurance to 28 double folds and reduced moisture content to 4.1%, whereas the moisture content was reduced but burst strength decreased to 250.5 kPa. Egg cartons made from corn were found to satisfy all the requirements tested for good packaging, while the reed-based cartons were found to have inadequate ink absorbency time (20 min), making them less printable. Overall, mixed corn residues seem to be the most promising raw materials for sustainable packaging, and wollastonite can be used to adjust the flexibility–strength balance. Full article

This study explores the use of metallurgical slag extracts as a liquid mineral fertilizer for maize cultivation. Slag samples were obtained from the former lead smelter in Shymkent and the Zhezkent Mining and Processing Plant. Elemental analysis identified the slag from the second storage area of the Shymkent smelter as the least contaminated with potentially toxic elements and enriched in macro- and micronutrients. Slag extraction was conducted via chemical leaching using potassium sulfate and ammonia solutions in a hydrogen peroxide medium, yielding Cu²⁺ and Zn²⁺ concentrations of 423.751 mg/L and 86.649 mg/L, respectively. The resulting extracts were diluted with distilled water at a ratio of 1:10 (potassium sulfate extract) and 1:200 (ammonia extract) and applied to assess early seed development and subsequent maize yield. Seed germination rates were comparable to those of the control group (100%). After 90 days of growth, maize plants treated with the ammonia-based extract showed positive effects on root system development, stem growth, and cob formation. The concentration of potentially toxic elements in the dry plant biomass remained within permissible limits. These findings demonstrate the potential for the safe agricultural use of these extracts while ensuring the rational utilization of industrial waste. Full article

Biosurfactant production by hydrocarbon-degrading bacteria is strongly influenced by the nature and concentration of available carbon substrates, which determine hydrocarbon bioavailability and microbial metabolic responses. In this study, five Bacillus subtilis strains isolated from weathered oil-contaminated sites in Qatar were evaluated for growth and biosurfactant activity using diesel fuel, fresh corn oil, and five-times-overheated corn oil as sole carbon sources. Cultures were grown in mineral salts medium under controlled conditions, and biosurfactant production was assessed through emulsification activity (EA), solubilization activity (SA), and colony-forming unit counts. All strains grew on the tested substrates but exhibited distinct strain-specific responses. Fresh corn oil supported the highest biomass production with values up to 3.3 × 10⁷ CFU mL⁻¹, whereas the strongest emulsification activity yield was observed in diesel cultures at low carbon loading (59 ± 2.3 EU g⁻¹ carbon. Five-times-overheated corn oil maintained more stable emulsification activity across a broader concentration range, indicating tolerance to oxidized hydrocarbons and adaptation to chemically altered substrates. Increasing hydrocarbon concentrations led to progressive declines in EA and SA, indicating inhibitory effects at high substrate loads. Overall, biosurfactant production did not correlate directly with biomass, highlighting the importance of substrate properties in regulating functional output. These findings demonstrate that substrate composition and concentration are key determinants of biosurfactant performance in B. subtilis isolates and support the potential use of waste oils as low-cost feedstocks for biotechnological and bioremediation applications. Full article

The increasing generation of agri-food waste represents a significant environmental challenge, but also a valuable source of bioactive compounds with potential industrial applications. In this study, selected minimally processed agri-food wastes from the food processing industry were evaluated as potential sources of bioactive compounds and antioxidants. Seven types of agri-food waste were investigated: green bean cutting waste, yellow bean cutting waste, sweet corn waste from the air selector, edamame pods, pepper seed by-products, potato peels, and potato waste from the air selector. Solid–liquid extraction was performed using ethanol at different concentrations (20, 40, 60, 80, and 96%, w/w) as a green solvent. Total polyphenol content (TPC) and antioxidant activity (DPPH, FRAP, and ABTS assays) were determined. The results demonstrated significant differences among the investigated raw materials, with the highest antioxidant activity observed in the potato peel extracts. Specifically, the strongest activity was recorded using 40% ethanol, yielding values of 3.9596 mg TE/g DW for DPPH and 11.4555 mg TE/g DW for ABTS assays. In contrast, the highest FRAP value (2.3970 mg Fe²⁺/g DW) was obtained with 60% ethanol. The highest TPC was detected in pepper seed by-products, reaching 6.7829 mg GAE/g DW when extracted with 20% ethanol. Furthermore, selected extracts were subjected to LC-MS analysis to obtain a preliminary characterization of their chemical profiles. Untargeted LC-MS analysis identified 115 metabolites belonging to different chemical classes, highlighting agri-food waste as a rich source of bioactive compounds, particularly flavonoids and phenolic acids. These findings demonstrate agri-food wastes as sustainable sources of bioactive compounds and support their valorization within circular economy and green processing frameworks. Full article

To promote the sustainable management of marine aquaculture waste, this study investigated the effect of corn stover biochar (300 °C, 400 °C, and 500 °C) on the mesophilic anaerobic digestion (37 ± 1 °C) of particulate matter from seawater aquaculture wastewater. Batch experiments evaluated biochar’s effects on methane production, microbial succession, and antibiotic resistance genes (ARGs), and the correlation between ARG abundance and microbial taxa. Biochar addition significantly enhanced biogas production and shortened the lag phase. During 60 h fermentation, the optimal treatment achieved a methane yield of 291 mL, which was 164.55% higher than the control. Metagenomic sequencing revealed that biochar altered microbial community structure and ARG profiles, reducing the 11 most prevalent ARG types. Glycopeptide resistance genes showed the greatest reduction (15.02%). Correlation analysis identified Enterococcus, Peptostreptococcus, and Clostridium as major ARG hosts, accounting for 64.78–69.81% of total ARG abundance in the control and 68.14–76.17% in the biochar-amended group, confirming that Firmicutes are key potential ARG carriers in marine aquaculture particulate waste. From the perspective of sustainable development, biochar addition improves energy recovery from aquaculture waste and mitigates ARG dissemination risk. This study provides practical guidance for material selection and process optimization in sustainable aquaculture biogas projects, supporting the transition toward a circular bioeconomy. Full article

Driven by global environmental regulations that strictly limit copper content in brake pads, traditional copper-based friction materials face significant challenges due to their negative ecological impacts. Consequently, the development of sustainable, copper-free alternatives has become an inevitable trend in the braking industry. This study proposes a novel approach to developing high-performance green friction materials by utilizing a synergistic combination of agricultural wastes, specifically corn cobs, wheat straw, rice husks, and sugarcane bagasse, and carbon fibers. Research indicates that the friction coefficient of the synergistic formulation remains stable within the range of 0.35 to 0.48. Compared with the control group, this formulation achieves an average reduction in the wear rate of 19.28% and an increase in the recovery rate of 5.15%, demonstrating superior tribological performance. The synergistic interfacial regulation between carbon fibers and agricultural waste facilitates the construction of a smooth and stable friction layer, which maintains consistent performance during extended operating conditions. Among all formulations investigated, the composite reinforced by the synergy of corncob and carbon fiber exhibits the most prominent comprehensive properties, with the wear rate decreasing by 28.73% and the recovery performance improving by 4.05% relative to the specimen containing copper fibers. This work not only provides a new pathway for the sustainable development of green friction materials but also offers a theoretical basis for the high-value utilization of agricultural waste resources. Full article

Sustainable agriculture requires careful evaluation of crop production materials, such as conventional mulching films, which improve yields and water efficiency but raise concerns related to waste, emissions, and supply chains. Assessing sustainable alternatives is therefore essential. This study compares the environmental life cycle impacts (LCA) and social impacts (S-LCA) of three agricultural mulching films: PLA-based, PBAT-based, and conventional LDPE film. The environmental assessment reflects conditions relevant to Lithuania, while the social assessment considers production contexts in Lithuania, Poland, and China. Results show that the highest environmental impacts occur during plastic granulate production, with PBAT generating 7.3 kg CO₂^eq, compared to 1.9 kg CO₂^eq for LDPE and 1.8 kg CO₂^eq for PLA (IPCC 100a method). Social risk analysis indicates that the main risks are associated with petroleum-based materials and, in the case of PLA, corn cultivation. PBAT-based films show the highest overall environmental impact; however, their ability to degrade in soil reduces the need for collection and transport. In contrast, LDPE films require removal and waste management but may offer more favorable outcomes when managed efficiently. Overall, while bioplastics involve diverse raw materials and energy-intensive production, conventional plastics may still provide lower environmental impacts under certain conditions. Full article

Valorization of abundant agricultural residues, particularly lignin, provides the opportunity to divert waste streams while enabling materials to inherently exhibit durable functionalities, including UV-blocking, antioxidant properties and water repellency. This study reports the side-by-side valorization of hemp hurd (HL) and corn stover lignin (CL), extracted using the CELF process, into electrospun lignin/nylon 6 nanofiber membranes, establishing how lignin botanical origin, molecular weight (M_w), and blend ratio govern multifunctional performance relevant to protective membranes in textiles. Lignin–nylon 6 hydrogen bonding was regulated by the OH content and accessibility, M_w, and purity, and influenced the functional properties of the fibers. While stronger in low-M_w nanofibers, these interactions were weakest in low-M_w HL samples due to the lowest purity, despite the highest OH content. Fibers with low-M_w lignin yielded finer, brittle fibers with higher UV blocking, whereas high-M_w fractions showed higher antioxidant performance due to decreased interactions with nylon 6. Overall, lignin/nylon 6 nanofiber membranes delivered biobased UPF 50+ performance, 55–61% antioxidant activity at the optimal concentration, and exhibited tunable water repellency via fraction selection and the blend ratio. In combination with a nanofiber architecture, these membranes can impart durable inherent functionality onto textile substrates without affecting their existing properties, including water vapor permeability, without the use of chemical finishing, while utilizing renewable resources from agricultural residues. Full article