Search Results (612)

Sugarcane bagasse (SCB) represents an abundant lignocellulosic residue with significant potential for integrated biorefinery applications. In this study, an alkaline extraction process was optimized for lignin recovery from SCB using a Box–Behnken Design (BBD) to evaluate the effects of extraction temperature (70–110 °C), NaOH concentration (3–9%, w/v), solid-to-liquid ratio (1:10–1:50, g mL⁻¹), and extraction time (30–90 min). Total phenolic content (TPC) and pure lignin content (PLC) were employed as response variables to identify optimal extraction conditions. Under the optimized parameters, a lignin yield of 17.7% and a TPC of 52.7 mg GAE g⁻¹ were achieved. Structural and thermal characterization by Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) confirmed the preservation of characteristic lignin functionalities and adequate thermal stability for downstream applications. To demonstrate its valorization potential, the recovered lignin was successfully incorporated as a partial substitute for petroleum-derived phenol in the formulation of a lignin-based resin, providing a proof of concept for its utilization in sustainable polymeric materials. In parallel, the cellulose-enriched residual solid (RS) obtained after lignin extraction was subjected to fermentation, yielding 10.3 g L⁻¹ ethanol. This integrated strategy enabled the sequential production of lignin-derived materials and bioethanol from a single biomass feedstock, maximizing resource utilization while minimizing waste generation. The findings highlight the feasibility of coupling lignin recovery with biofuel production and support the development of SCB-based biorefineries for the generation of renewable chemicals, bio-based materials, and sustainable energy carriers. Full article

Cinnamoyl coenzyme A reductase (CCR) is the first rate-limiting enzyme in the monolignol-specific pathway and plays a pivotal role in lignin biosynthesis. However, CCR genes in Pinus yunnanensis remain uncharacterized, and their undefined substrate specificity further impedes mechanistic insights into lignin regulation while restricting strategies for wood property optimization. Using conserved domain and homology analysis, with a focus on the characteristic NAD(P)-binding motif (KNWYCYGK), we identified 12 CCR family members from the transcriptome data of P. yunnanensis. Phylogenetic analysis clustered the PyCCRs into two distinct clades: PyCCR1~6 fall into the CCR clade, while the remaining members form a CCR-like clade. In this study, twelve ORF regions of the P. yunnanensis CCR genes were cloned, and nine purified recombinant PyCCR proteins were obtained through prokaryotic expression. In vitro enzymatic assays demonstrated that PyCCR1, PyCCR2, PyCCR5, and PyCCR6 catalyzed the conversion of p-coumaroyl-CoA, feruloyl-CoA, and sinapoyl-CoA to p-coumaraldehyde, coniferaldehyde, and sinapaldehyde, respectively. Molecular docking of PyCCR1 to 6 with three substrates identified substrate-binding pocket domains. Within these domains, hydrogen bonds formed between ligands and residues in the R(X)5K motif of PyCCR1 to 6, whereas PyCCRL7 to 12 lacked the complete motif. RT-qPCR analysis showed tissue-specific expression patterns of the 12 genes across buds, stems, leaves, roots, and fruits. Collectively, these findings suggest that the presence of a complete R(X)5K motif may play a crucial role in maintaining the catalytic activity of PyCCRs. Our present study established a mechanistic foundation for elucidating lignin biosynthesis regulation in P. yunnanensis and offer genetic resources for improvement programs. Full article

The construction sector is under enormous pressure to reduce the overall environmental impact of its activities, which, for cement production alone, cause over 2 Gt/yr of CO₂ emissions (2022). Given the massive scale of concrete production, even minor components such as plasticizers, typically required in quantities of only a few percent of the dry cement mass, correspond to production volumes of many tens of Mt/yr, making their sustainability highly relevant. Lignin is the second most abundant renewable biopolymer on Earth and is currently used in concrete formulations mainly as a low-performance cement plasticizer. Despite this limited application, lignin represents an underexploited but highly attractive raw material for the development of environment-friendly concrete additives, owing to its abundance and availability from industrial biomass residues. The purpose of this review is to provide a specific and up-to-date overview of the various approaches for developing sustainable, high-performance concrete plasticizers based on lignins derived from industrial waste streams. The state of the art in the field is put into perspective by considering the various industrial sources of original technical lignins, the processes that led to their formation, and potential strategies for improving their characteristics. A quick overview of the patent history of the field complements the analysis of the scientific literature. An integral part of this work is a concise introduction to the fundamentals of cement chemistry and rheology, which are essential for understanding the technological requirements for effective concrete admixtures and for enabling cross-disciplinary research between the lignin and cement communities. Full article

Microbial degumming offers an eco-friendly alternative to chemical methods for ramie fiber production, but industrial application is constrained by low efficiency stemming from limited mechanistic insight. This study systematically investigates the process using Pectobacterium carotovorum HG-49. Strain HG-49 showed a lag phase of 0–4 h, a logarithmic phase of 6–10 h, and peak biomass at 12 h. Pectin (97.05%) and water-soluble substances (98.45%) were nearly fully removed, whereas hemicellulose removal was only 73.54%, rendering it the primary residual gum component. Pectinase activity peaked at 120.75 U/mL, while mannanase (35.85 U/mL) and xylanase (30.20 U/mL) reached roughly one-quarter of that level; cellulase activity remained minimal. Scanning electron microscopy (SEM) indicated that 6–12 h constituted the main gum degradation phase. Fourier transform infrared spectroscopy (FTIR) and micro-FTIR showed progressive decreases in pectin, hemicellulose, and lignin absorption peaks with degumming. X-ray diffraction (XRD) revealed increased crystallinity from 72.07% to 80.02%, and thermogravimetric analysis (TGA) showed elevated degradation temperature from 417 °C to 435 °C. Collectively, these data confirm progressive removal of gummy substances and enhanced cellulose purity. Transcriptomic profiling further revealed that low abundance and reduced expression of hemicellulases significantly limited degumming performance. Therefore, enhancing efficiency should focus on: supplementing pectin-rich substrates to accelerate bacterial proliferation and enzyme production, broadening the hemicellulase spectrum and enhancing catalytic activities and establishing effective pretreatment protocols for ramie bast. These findings provide a theoretical foundation for improving microbial degumming efficiency and advancing industrial feasibility. Full article

Most research on Nanobubble Water (NBW) for lignocellulose conversion has focused on anaerobic digestion, with relatively few studies examining direct pretreatment methods such as liquefaction. In this study, we explored the potential of NBW as a pretreatment method for bagasse meal liquefaction. Bagasse meal was treated with oxygen, nitrogen, and carbon dioxide NBW. Changes in component composition ratio, crystallinity, total crystallinity index (TCI), lateral order index (LOI), pyrolysis peak temperature (T_max), and apparent activation energy (E_a′) were investigated. For the liquefaction process, changes in residue content, apparent liquefaction reaction rate constant (k′), average molecular weight, hydroxyl value, functional group information, and T_max of the liquefied residue were examined. Results showed a 2.0–3.0% decrease in cellulose and a 1.0–4.0% decrease in lignin. Crystallinity increased by 5.8–12%, TCI decreased by 6.7–13%, and LOI increased by 4.7–9.8%. T_max decreased by 1.6–3.5 °C, and E_a′ decreased by 1.9–2.8%, both reaching their lowest values with carbon dioxide NBW. At this time, the residue content decreased by 6.3–19%, and k′ increased by 50%. These findings indicate that NBW pretreatment is a promising approach for liquefying bagasse meal under laboratory conditions. Future investigations will be directed towards its scalability and economic viability. Full article

The efficient utilization of natural resources and agricultural wastes aligns well with the UN Sustainable Development Goals. Sunflower seed husks are an affordable and renewable source of cellulose that can be used as an alternative to wood-based resources. However, the yield and quality of cellulose are affected by the presence of components such as phytomelanin, hemicellulose, and lignin. In this study, cellulose pulp (CP) was extracted from untreated, water-treated, and water and alkali-treated SFH. The optimal peroxyacetic acid (PAA) to biomass ratio was established to assess the influence of pre-treatment on CP properties. Water and alkali pre-treatments significantly increased CP yield and reduced residual lignin, hemicellulose, and ash compared to untreated samples. The optimal yield of CP for SFH-NaOH was 55.73%. All microcrystalline cellulose (MCC) types exhibited comparable α-cellulose content, confirmed by the IR band at 1430 cm⁻¹. XRD showed lower crystallinity in untreated CP-SFH relative to pre-treated samples. SEM revealed porous fibrous structures across all MCCs. Pre-treatment also improved the thermal stability and ζ-potential of cellulose nanocrystals (CNCs) obtained from MCC, without altering morphology. CNC yields were determined for all three CP variants. The CP-SFH-NaOH sample had the maximum CNC yield of 52.12%. Phytomelanin with admixture of lignin was recovered from alkaline extracts (8.56%) and fully characterized. Overall, the findings demonstrate the potential of integrated SFH utilization to produce high-quality cellulose derivatives and phytomelanin with admixture of lignin. Full article

Citrus peel, a major by-product of citrus processing, is a rich source of pectin and other bioactive compounds. In this study, pectin extracted from seven citrus species was comprehensively characterized for its structural, spectral, thermal, physicochemical, techno-functional, antioxidant, and anti-amylase properties. The extracted pectin (~50% methyl esterification) contained residual cellulose, hemicellulose, lignin, and proteins, with Fourier-transform infrared (FTIR) and ultraviolet-visible (UV-Vis) confirming typical galacturonic acid-based structures. Fluorescence analysis revealed emission shifts (420–500 nm) compared to standard pectin. Thermal analysis indicated multi-stage degradation, with major transitions linked to moisture loss, polysaccharide depolymerization, and lignin oxidation. X-ray diffraction (XRD) confirmed a predominantly amorphous structure with minor cellulose domains. The pectin solution showed negative zeta potential, shear-thinning behavior, and high conductivity. Functionally, it exhibited strong swelling, hygroscopicity, and water/oil holding capacity, but low foaming ability. Biologically, it demonstrated moderate antioxidant activity and α-amylase inhibition. These findings highlight citrus pectin as a promising sustainable ingredient for food and pharmaceutical applications, with future work needed to enhance its solubility and bioactivity. Full article

Coconut husk lignin was fractionated using ethanol to obtain nanolignin fractions with distinct physicochemical properties. Among the fractions, CNF1 exhibited the most favorable combination of particle size, thermal stability, and antibacterial activity and was selected for further modification. Microwave-assisted esterification of CNF1 with maleic anhydride was performed under various reaction temperatures and lignin-to-maleic anhydride ratios. Structural modification was confirmed by ATR-FTIR spectroscopy through the appearance of ester carbonyl groups and an increase in the degree of esterification, which reached its highest value at 180 °C and a lignin-to-maleic anhydride ratio of 1:10. TEM analysis revealed that maleation increased nanoparticle size, whereas WAXD demonstrated that both native and modified lignins retained predominantly amorphous structures. Antioxidant activity decreased with increasing esterification due to the reduction of phenolic hydroxyl groups. Thermal analysis showed that esterification altered the degradation behavior of lignin, while thermo-oxidative stability measurements indicated improved oxidation resistance for highly esterified samples. The 10MA180 sample exhibited the highest thermo-oxidative stability, with a T₂,O₂ value of 12.55 min, a residual mass of 84.90%, and the lowest weight loss after 60 min oxidation. These findings demonstrate that microwave-assisted maleation effectively tailors the structure and functional properties of nanolignin for sustainable bio-based material applications. Full article

Wood- and lignocellulosic-residue-derived constituents have attracted increasing attention in cementitious materials because they may support clinker reduction, waste valorization, moisture regulation, crack control, and longer service life. This review synthesizes evidence on wood ash, wood-derived biochar, and wood or lignocellulosic fibers in low-clinker and low-carbon-oriented cementitious systems, with emphasis on severe cold service involving freeze–thaw cycling, salt freezing, and chloride ingress. This review clarifies the evidence boundaries among direct wood-derived materials and related biomass or lignocellulosic analogues, because wood ash, non-wood biomass ashes, such as bamboo ash and bagasse ash, wood fiber, and non-wood plant fibers cannot be treated as equivalent materials. Wood ash is best regarded as a controlled partial binder replacement or filler whose performance depends on combustion temperature, oxide composition, alkali content, residual carbon, fineness, and water demand. Biochar is more appropriately treated as a low-dosage functional additive, commonly in the range of approximately 1–3 wt.% of binder, where it may assist internal curing, nucleation, moisture redistribution, and pore regulation; excessive dosage can increase porosity and reduce mechanical or transport performance. Wood and lignocellulosic fibers mainly contribute to crack control, toughness, and post-cracking behavior, but their effectiveness is limited by water absorption, swelling, lignin- and extractive-related hydration interference, and long-term interfacial degradation in alkaline matrices. Across these material classes, engineering performance is governed by the interfacial transition zone, pore-size distribution, moisture state, air–void compatibility, and exposure-specific durability response. The main contribution of this review is to propose a boundary-conscious framework for material classification, quantitative comparison, mixture-design screening, and severe-cold durability qualification. Future application requires source-specific characterization, water-demand control, treated fibers, low-dosage biochar optimization, and service-informed testing that couples freeze–thaw cycling, chloride transport, saturation state, and microstructural verification. Full article

Corn stover is an abundant, low-cost, and representative lignocellulosic agricultural residue for bioethanol production, but its recalcitrant structure requires effective pretreatment to improve downstream conversion performance. Ball milling technology has been widely used to pretreat lignocellulosic biomass, where regulating particle size distribution enhances lignin utilization and subsequent ethanol production. However, systematic optimization of ball milling operating parameters remains insufficiently investigated. To bridge the gap between bench-scale experimentation and process-level performance prediction, this study establishes an integrated experimental and simulation framework. Ball milling experiments are conducted to systematically vary key operating parameters, and particle morphology is precisely quantified through optical imaging coupled with digital image analysis. Empirical correlations between these operating conditions and particle size characteristics are derived through polynomial fitting. These correlations are then embedded into an Aspen Plus process model for bioconversion performance evaluation. Evaluation from this integrated framework reveals that system-level optimization of the pretreatment process effectively reduces mean particle size, narrows size distribution, and increases specific surface area. By systematically evaluating the operating space, an optimal window that yields a 2.97% improvement in glucose conversion is identified. This work provides practical guidance and a generalizable framework for optimizing mechanical pretreatment to maximize target product yields. Full article

Rice straw, one of the most abundant agricultural residues worldwide, remains significantly underutilized as a ruminant feed source owing to its intrinsic lignocellulosic recalcitrance. This study investigated the effects of co-extruding rice straw with varying proportions of corn flour on nutritional composition and in vitro digestibility for ruminant nutrition. Extrusion was conducted using a twin-screw extruder at 180 °C barrel temperature, 5 MPa pressure, and 50% feed moisture content. Five corn levels were formulated on a dry matter basis: pure rice straw (RS100); three blends with increasing corn flour inclusion: RS75:C25 (75% straw + 25% corn flour), RS67:C33 (67% straw + 33% corn flour), and RS60:C40 (60% straw + 40% corn flour); and pure corn flour (C100) as a control. Chemical composition including neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), cellulose, hemicellulose, water-soluble carbohydrates (WSC), and starch was analyzed. In vitro dry matter digestibility (IVDMD) was determined using a pepsin-cellulase assay. Regression analysis within the practical 0–40% corn flour inclusion range revealed a significant quadratic relationship with IVDMD (R² = 0.999, p < 0.001). The optimal corn flour proportion was calculated to be approximately 37.5%, which closely matched the RS60:C40 formulation (40% corn flour). Among the tested formulations, RS60:C40 exhibited the greatest extrusion-induced nutritional improvements. Relative to its pre-extrusion values, cellulose decreased by 55.7% (p < 0.05), followed by ADF (16.1%), NDF (12.8%), and hemicellulose (10.2%); IVDMD increased by 34.2% (p < 0.01) and WSC by 56.7% (p < 0.05). Compared with RS100 after extrusion, RS60:C40 raised IVDMD by 49.5% and lowered cellulose by 60.6%. Its IVDMD also surpassed those of RS75:C25 and RS67:C33 (p < 0.05), whereas RS75:C25 showed only marginal improvements. ADL content showed no extrusion-induced change (p > 0.05). Scanning electron microscopy (SEM) of the RS60:C40 formulation revealed that, unlike the intact fibrous structures observed prior to extrusion, post-extrusion samples exhibited extensive disruption of the fibrous matrix. Pearson correlation analysis further supported these findings, showing strong positive correlations between IVDMD and WSC (r = 0.96, p < 0.001) and strong negative correlations between IVDMD and NDF (r = −0.95, p < 0.001). In conclusion, extrusion generally increased IVDMD and WSC while reducing fiber fractions, with the effect depending on corn level. Co-extrusion with 40% corn flour effectively enhanced the nutritional value of rice straw, offering a viable strategy for producing a more digestible ruminant feed. Full article

Anaerobic digestion (AD) of lignocellulosic biomass is often constrained by biomass recalcitrance, limiting methane recovery. This study investigated whether low-temperature dilute-acid hydrothermal pretreatment could enhance methane production from pine nut shells (PNSs), a lignin-rich and underutilized agro-industrial residue, and whether derivative-based kinetic landmarks could provide a more systematic characterization of batch AD performance. Methane production was significantly improved by dilute sulfuric acid and hydrothermal pretreatments. The highest methane yield (201.8 mL CH₄ g⁻¹ VS) was achieved under the combined 100 °C hydrothermal and 2.5% H₂SO₄ condition, representing approximately 1.8-fold and 3.3-fold increases compared with hydrothermal-only and untreated PNSs, respectively. Enhanced performance was attributed to hemicellulose solubilization, lignin disruption, and improved substrate accessibility. In contrast, excessive acid severity resulted in process instability, associated with total volatile fatty acid accumulation and pH reduction. The Modified Logistic Model (MLM) was further used to derive five kinetic landmarks (PAA, PAM, PI, PDM, and PDA) describing phase-specific features of cumulative methane production curves. While these landmarks provide a model-based framework for comparing batch AD kinetics, their nearly constant normalized yields primarily reflect the geometry of the fitted logistic function rather than independent biological invariants. Overall, the results identify 100 °C hydrothermal pretreatment with 2.5% H₂SO₄ as an effective moderate-severity strategy for enhancing methane recovery from PNSs and demonstrate the utility of MLM-derived landmarks as comparative descriptors of phase-resolved methane production. Full article

With the expansion of modern protected agriculture, the amount of post-harvest tomato biomass has increased sharply. Conventional unmanaged disposal practices disrupt carbon flows and cause substantial environmental emissions. Tomato plant residues (TPRs), which are rich in lignocellulose and selected high-value secondary metabolites, have considerable potential as feedstocks for green industrial materials. However, their complex biophysical properties, high physiological moisture content, and recalcitrant cell-wall barriers hinder large-scale processing. This review systematically examines the mechanisms and process architectures for converting TPRs into macromolecular products. First, it analyzes cross-scale anatomical heterogeneity and dynamic rheological properties of TPRs, defining their physicochemical boundaries as industrial precursors. Second, it summarizes the development of physical field-coupled equipment, ranging from anti-tangling harvest-shredding to die-roller densification. Furthermore, it examines the core mechanisms of multi-field-coupled pretreatment technologies, including steam explosion, deep eutectic solvents (DES), and mechanochemistry, in deconstructing vascular skeletons and reducing multiphase mass-transfer resistance. Finally, this review discusses reconstruction pathways for TPR-derived components in advanced polymer materials, including biodegradable nanocellulose films, bio-based composites, aerogels, and lignin-based polyurethane networks. Overall, it links microscopic reaction kinetics with macroscopic equipment engineering, proposes a closed-loop material conversion system from in-field volume reduction to cascaded biorefinery, and provides an engineering framework for future multi-machine intelligent collaboration and continuous production across the industrial chain. Full article

The agrifood industry generates substantial amounts of waste to meet the increasing global food demand, raising environmental concerns. Valorization of these residues through the recovery of high-added-value compounds and renewable energy production, such as biogas via Anaerobic Digestion (AD), offers a sustainable solution. In this study, the potential of Olive Pomace (OP), Brewers’ Spent Grain (BSG), and Cereal Wheat Bran (BR) as substrates for AD was investigated. Lignin was removed from these biomasses using an Ionic Liquid (IL) composed of triethylamine and sulphuric acid ([Et₃N][HSO₄]), and the delignified residues, called Olive Pomace Pulp (OPP), Brewers’ Spent Grain Pulp (BSGP), and Cereal Wheat Bran Pulp (BRP), were evaluated for their biogas and biomethane production potential through the volumetric method, coupled with an alkaline trap for biogas upgrading. An analysis was performed, considering biogas and biomethane yields, AD duration, and energy requirements. Raw biomasses provided different biomethane concentrations, with OP reaching 53.73%, BSG 76.59%, and BR 77.36%. After IL treatment, the methane content was 55.6% for OPP, 60.0% for BSGP, and 54.6% for BRP. Owing to their similar composition, BSG and BR displayed comparable biomethane production profiles. The analysis highlighted BSG and BR as the most efficient substrates for AD following lignin removal. Overall, this approach demonstrates the potential of agro-industrial waste valorization to produce bioenergy and support the transition toward a circular economy. Full article

Vine shoot residues represent an abundant lignocellulosic by-product of the wine industry and a promising source of phenolic compounds with potential functional applications. In this work, a biocatalytic strategy combining aqueous citric acid treatment and subsequent laccase-mediated oxidation was developed for the valorization of vine shoot-derived phenolic liquors. The pretreatment was optimized by response surface methodology, and the selected conditions, 190 °C, 75 min, and 0.82% citric acid, yielded a pretreated solid containing 2.9 ± 0.02% hemicellulose, 47.5 ± 0.20% cellulose, and 51.8 ± 1.87% lignin, together with a phenolic-rich liquor containing 27.66 ± 0.39 mg GAE g⁻¹ dry solid. Chemical characterization by UHPLC-timsTOF-MS revealed a complex mixture of phenolic acids, lignin-derived compounds, carbohydrate derivatives, and secondary metabolites. Laccase-catalyzed oxidation was first used as a reactivity assessment step, showing that the phenolic compounds present in the liquor were susceptible to enzymatic transformation. This treatment decreased the total phenolic content, antioxidant capacity, and antimicrobial activity of the liquor. Subsequently, enzymatic oxidation was carried out in the presence of starch, yielding washed starch solids with retained Folin-reactive phenolic content of approximately 4 mg GAE g⁻¹ starch and measurable antioxidant capacity. Overall, this study demonstrates an integrated valorization route in which citric acid-assisted fractionation of vine shoot residues generates phenolic-rich liquors that can be chemically characterized, enzymatically activated, and directly used for starch functionalization, providing a sustainable strategy to convert agro-industrial residues into bio-based functional systems. Full article