Search Results (375)

The effects of pectin extraction, cellulose purification, and sonication on the juice extraction residue from grapefruit were investigated. Pectin extraction using pressurized carbon dioxide (pCO₂) in a sodium oxalate solution (U-OX) lowered the cellulose content and increased the hemicellulose and lignin contents, whereas pectin extraction in deionized water (U-DW) did not affect these contents. Pectin extraction and cellulose purification induced hydrolysis and removal of non-crystalline cellulose regions. The sonication of the purified cellulose samples formed fiber-like structures with widths of <100 nm on their surfaces. The cellulose purification process increased the surface charge and formed a gel-like structure with increased hardness, adhesiveness, and film structure. These processes enhance the absorption of amphiphilic dyes, although to a lesser extent than that of the untreated juice extraction residue (UJR) after sonication. Before sonication, UJR adsorbed cationic dyes, whereas after, UJR adsorbed both polar and nonpolar dyes. These results suggest that juice residue could be used as a biomaterial with diverse potential applications. Full article

This study investigates the long-term service effects on Chinese fir (Cunninghamia lanceolata) components from ancient timber buildings in southern China. Anisotropic mechanical tests were performed to examine the evolution of mechanical properties from the perspectives of moisture absorption behavior, chemical composition, and microstructural characteristics. The results show that, after approximately 217 ± 12 years (Lvb specimens) and 481 ± 23 years (Xuc specimens) of service, the longitudinal compressive strength and corresponding elastic modulus of Chinese fir increased by about 11% and 15% and 33% and 71%, respectively, compared with fresh timber. The bending strength of the Lvb sample exhibited a slight reduction (approximately 6%), whereas the Xuc specimens showed the highest increase (33%). This difference is mainly attributed to long-term bending loads that caused structural damage in the Lvb beam specimens. In contrast, changes in lateral mechanical properties were negligible. Chemical composition analysis revealed an increase in extractive content and a reduction in cellulose and hemicellulose, leading to a notable rise in crystallinity. Scanning electron microscopy (SEM) observations further showed interlayer separation, wrinkling, and local collapse of the cell walls, suggesting significant cell wall densification. Overall, the evolution of mechanical properties is governed by the combined effects of increased crystallinity and microstructural densification, which together enhance the longitudinal and bending performance of aged timber with increasing service time. The findings provide a scientific basis for evaluating the performance and structural safety of aged timber components in the conservation of ancient timber buildings. Full article

For the first time, Eriolobus trilobatus bark from Turkey has been characterized in terms of its chemical, extractive, fuel, and ash characteristics using SEM–EDS, wet chemical analysis, phenolic analysis, FT-IR, TGA, XRF, XRD, BET surface area measurement, proximate analysis, and ash fusion temperature (AFT) determination. The results showed that the bark contains 13% ash, dominated by calcium oxalate, and 15% extractives, largely composed of polar phenolic compounds with moderate radical-scavenging potential. Thermal decomposition of bark proceeds in four distinct stages, associated with the sequential degradation of extractives/hemicelluloses, cellulose, lignin/suberin, and inorganic fractions. The higher calorific value of 14.9 MJ/kg indicates moderate fuel quality compared with conventional woody biomass. Ash is mesoporous with a CaO-rich structure highly suitable for catalytic applications in biodiesel production and biomass gasification. Ash fusion analysis revealed a high flow temperature (1452 °C), indicating a very low slagging risk during thermochemical conversion. Overall, E. trilobatus bark is a promising material for value-added biorefinery pathways, enabling processes for the production of biochars, CaO-based catalysts, phenolic extracts, and sustainable energy. The valorization of E. trilobatus bark not only enhances the economic potential of forestry residues but also provides environmental co-benefits through carbon soil amendment and landscape applications. Full article

The brewing industry produces a large amount of byproducts, primarily brewery spent grain (BSG), which mainly consists of carbohydrates, proteins, and lipids. The different fractions isolated and extracted from BSG have significant potential for waste valorization and could be used as functional products or food ingredients. In this study, specific BSG-derived fractions (Hemicellulose A, Hemicellulose B, and oligosaccharides) were isolated and characterized to evaluate their potential applications. Thermogravimetric analysis data showed that the residue at 600 °C for various fractions is approximately 20% under N₂, compared to 10% in air for BSG fractions. The rheological properties of Hemicellulose A and Hemicellulose B fractions from brewers’ spent grain (BSG) exhibit high viscosity, suggesting a strong dependence on molecular weight. This characteristic implies that their elevated molecular size may play a key role in their capacity to form gels, potentially enhancing their functionality in applications requiring thickening or structural integrity. Among the BSG fractions, Hemi. It had a viscosity of >102 mPa s⁻¹ at a 3% (w/v) concentration, which was higher than Hemi B and oligosaccharides at the same concentration. The zeta potential of BSG fractions at various pH and concentrations was measured to assess the effects of pH and concentration. Additionally, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) revealed the surface morphology and composition of each fraction. The highest Phosphorus (P) (%) was found on the surfaces of both Hemi B and the hexane-extracted BSG. The surface elements of each fraction primarily included C, O, N, P, Ca, and Mg. Full article

The standard methods for determining the basic chemical composition of wood are well-established, but include processes that demand a great deal of time and diverse chemical reagents. TGA and DTG analyses, in contrast, offer precise results in less time. This study was designed to identify the primary components and results of the proximal analysis of wood from three species –Acacia farnesiana, A. pennatula and Albizia plurijuga—using TGA with deconvolution of the DTG curve and a chemical method. Higher heating value (HHV) was determined using a bomb calorimeter and mathematical models. Elemental organic and inorganic analyses were conducted. No statistically significant differences appeared in the results of the TGA-DTG and chemical methods for the wood in terms of cellulose, lignin, and volatile material content. Results were especially accurate in the samples of A. pennatula and A. plurijuga for hemicelluloses, extractives, and moisture. Regarding HHV, the wood of A. plurijuga showed no statistically significant differences between the bomb calorimeter test, calculations as a function of chemical composition, or the proximal analysis. Elemental organic results were C = 43.76–46.65%; H = 6.70–6.95%; O = 46.06–48.95%; N = 0.21–0.42%; and S = 0.06–0.11%. For the inorganic fraction we identified 18 elements in the ash. We conclude that the TGA-DTG method made it possible to obtain results in a short time with no need for the numerous reagents that chemical processes require. Findings suggest that in the absence of a bomb calorimeter, the best model for calculating HHV is proximal analysis. Full article

Banana pseudostem is an abundant lignocellulosic residue with potential for value-added applications. This study evaluated five banana varieties to determine their suitability for bioplastic production, with Williams showing the highest cellulose yield (26.99% ± 0.23). Cellulose extracted from this variety was combined with corn-starch (1:1 w/w) to synthesize a bioplastic through gelatinization and lyophilization. FTIR confirmed effective removal of lignin and hemicellulose from the pseudostem and evidenced new hydrogen-bond interactions between cellulose and starch through O–H band shifts (3335 → 3282 cm⁻¹). SEM revealed a porous laminar morphology with cellulose particles (40–52 µm) embedded within the starch matrix. DSC analysis showed that the bioplastic exhibits an intermediate thermal profile between its components, while mechanical compression increased the endothermic transition temperature (from 69 °C to 85 °C) and reduced molecular mobility. Tensile testing demonstrated that compression markedly improved mechanical performance, increasing tensile strength from 0.094 MPa to 0.69 MPa and density from 110 to 638.7 kg/m³. These findings indicate that cellulose–starch bioplastics derived from banana pseudostem possess favorable structural, thermal, and mechanical characteristics for short-use applications. The approach also contributes to the valorization of agricultural waste through biodegradable material development. Full article

This study examines the thermal modification (TM) of European black alder (Alnus glutinosa) wood boards measuring 1000 × 100 × 32 mm. The TM was carried out in a nitrogen atmosphere under an initial pressure of 4 bar at 160 °C for 60, 120, and 180 min, as well as at 170 °C for 30 and 60 min. The TM process resulted in mass loss and volumetric changes with shrinkage observed across all anatomical directions. Water uptake decreased significantly, with the cell wall’s total water capacity dropping from 35% to a range of 14%–27%. Dimensional stability was improved by between 21% and 61%. The TM wood showed a reduction exceeding 50% in both volumetric swelling and equilibrium moisture content relative to the unmodified specimens. A marked decline in the modulus of rupture was observed, especially in samples treated at 160 °C for 180 min and at 170 °C. Conversely, the modulus of elasticity exhibited a slight upward trend, though the changes were not statistically significant. Brinell hardness revealed a pronounced difference between the tangential and radial orientations, with the tangential surface displaying distinctly lower hardness. Chemical analysis indicated a notable increase in acetone-soluble extractives and reductions in the xylan, mannan, and acetyl groups, reflecting structural alterations in hemicelluloses. Full article

Cocoa pod husk (CPH) is a potential material to produce value-added products. The objective of this study was to optimize the microwave-assisted hydrothermal pretreatment (MA-HTP) of CPH and CPH hemicellulose (HMC-CPH) using only water as the extraction medium, in combination with response surface analysis (RSA), Box–Behnken design (BBD), and proton nuclear magnetic resonance identification and quantification (¹H NMR Qu) to provide an efficient protocol for the extraction of mono- and disaccharides, as a novel method for which no precedent was found. The methodology consisted of 15 CPH MA-HTPs and 15 HMC-CPH MA-HTPs (triplicate) designed by RSA-BBD; the experimental variables were time, temperature, and power, and the response was the concentration of extraction products. Glucose, sucrose, and fructose were identified as products of the extractions by ¹H NMR. With 95% confidence, higher sucrose content was determined for CPH (45.62%) compared to HMC-CPH (17.34%), high fructose content for both CPH and HMC-CPH (37.88% and 35.37%, respectively), and minimal glucose concentrations were obtained in both CPH and HMC-CPH (4.57% and 0.93%, respectively). Using RSA-BBD, optimal temperature, power, and time points were predicted for glucose CPH: 135.4 °C, 180.6 W, and 5.8 min; sucrose: 154.3 °C, 256.3 W, and 20. 2 min; fructose 129.5 °C, 173.8 W, and 5.27 min. For HMC-CPH, the optimal conditions were as follows: glucose: 142.2 °C, 204.4 W, and 10.5 min; sucrose: 148.8 °C, 215.6 W, and 14.3 min; fructose: 151.6 °C, 231.6 W, and 13 min. Full article

Rice is a staple food for global nutrition, and its processing generates large volumes of waste with a consequent environmental impact. The industry needs to improve its capacity to manage and treat this waste with more sustainable options than traditional management methods, thereby mitigating the environmental impact of the rice industry. Among the waste streams generated, rice bran represents a significant fraction that is largely underutilized. This study proposes a comprehensive approach to rice bran recovery, aiming to transform 100% of the waste into bio-based products through a three-stage biorefinery approach that combines chemical and biological operations. The process began with the ethanolic extraction of rice bran, which yielded 20.58% (w·w⁻¹) rice bran oil. This oil, evaluated through both in vitro and in vivo trials, has demonstrated effectiveness when combined with commercial edible coatings, reducing post-harvest damage in grapes and lemons by 15–20%. Following extraction, the remaining defatted rice bran, accounting for 79.42% (w·w⁻¹) of the initial material, was used as a carbon-rich substrate for microbial fermentation by Haloferax mediterranei. This step converts 28.75% (w·w⁻¹) of rice bran into microbial biomass and 12.75% (w·w⁻¹) into polyhydroxybutyrate-valerate. The undigested residual biomass, comprising 37.95% (w·w⁻¹) of the starting material, was further valorized through the purification of high-value products such as cellulose (13.08% (w·w⁻¹)), hemicellulose (14.58% (w·w⁻¹)), and lignin (10.29% (w·w⁻¹)). Overall, the biorefinery model recovers 100% of the initial waste and demonstrates, under laboratory conditions, the model’s ability to transform rice bran into six products of industrial interest, offering an option with the potential to effectively manage rice bran waste and help circularize the production model of an industry that traditionally operates under a linear production model. Full article

Lignocellulosic biomass—the non-edible fraction of plants composed of cellulose, hemicellulose, and lignin—is the most abundant renewable carbon resource and a key lever for shifting from fossil to bio-based production. Agro-industrial residues (straws, cobs, shells, bagasse, brewery spent grains, etc.) offer low-cost, widely available feedstocks but are difficult to process because their polymers form a tightly integrated, three-dimensional matrix. Within this matrix, lignin provides rigidity, hydrophobicity, and defense, yet its heterogeneity and recalcitrance impede saccharification and upgrading. Today, most technical lignin from pulping and emerging biorefineries is burned for energy, despite growing opportunities to valorize it directly as a macromolecule (e.g., adhesives, foams, carbon precursors, UV/antioxidant additives) or via depolymerization to low-molecular-weight aromatics for fuels and chemicals. Extraction route and severity strongly condition lignin structure linkages (coumaryl-, coniferyl-, and sinapyl-alcohol ratios), determining reactivity, solubility, and product selectivity. Advances in selective fractionation, reductive/oxidative catalysis, and hybrid chemo-biological routes are improving yields while limiting condensation. Remaining barriers include feedstock variability, solvent and catalyst recovery, hydrogen and energy intensity, and market adoption (e.g., low-emission adhesives). Elevating lignin from fuel to product within integrated biorefineries can unlock significant environmental and economic benefits. Full article

Lignocellulosic residues represent a promising source of raw material for obtaining several high-value bioproducts, including cellulose and derivatives. One of the main barriers to cellulose extraction from these residues is the presence of other components associated with the cellulose matrix, such as lignin and hemicellulose. To overcome this limitation, it is necessary to apply specific treatments to remove these constituents. In this study, the effectiveness of three chemical treatment methods in the purification of cellulose extracted from urban pruning biomass of the species Clitoria fairchildiana were evaluated, namely (i) alkaline treatment using dilute sodium hydroxide solution; (ii) alkaline treatment followed by bleaching with hydrogen peroxide; and (iii) alkaline treatment followed by bleaching with hydrogen peroxide and sodium hydroxide combined. The changes in chemical composition and thermal properties caused by each method were analyzed using techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results demonstrated that the biomass pretreatment reduced the content of impurities, lignin, and hemicellulose, increasing the cellulose content to 37.16% in the combined treatment (H₂O₂ + NaOH). Furthermore, the FTIR spectra revealed characteristic bands of important functional groups, which reaffirmed the chemical structure of the extracted cellulose through the identification of hydroxyl, carbonyl groups, and C-H bending vibrations. Additionally, the SEM results indicated an increase in specific surface area and greater exposure of fibrils, providing visual confirmation of the removal of constituents from the cellulosic matrix. Collectively, these results demonstrate the potential of combined chemical treatments for the valorization of Clitoria fairchildiana biomass and indicate its technical feasibility for obtaining cellulose with a higher degree of purity. Full article

Plastic materials are widely used for packaging due to their versatility and availability. Global production, mainly from petrochemicals, is estimated at 380 million tons, increasing annually by 4%. Packaging plastics have the shortest lifespan and contribute significantly to environmental pollution. Current production, use, and disposal of these plastics harm the environment, hu-mans, and ecosystems. Microplastics, (plastics particles ranging from 1 µm to 5 mm) formed through degradation, accumulate in ecosystems and the human body, including the brain. Bioplastics and biodegradable polymers from biological sources are a sustainable alternative; however, most production still relies on food crops, raising concerns about food security and sustainability. Utilizing organic wastes reduces production costs, lessens pressure on food systems, and supports waste management efforts. Cellulose, an abundant natural polymer, offers strong potential due to biodegradability, availability, and mechanical properties. This review explores extracting cellulose from banana pseudostem waste for packaging, high-lighting extraction and conversion methods and characterization via FTIR, TGA, SEM, XRD, and mechanical testing. FTIR confirmed the effective removal of lignin and hemicellulose, XRD revealed increased crystallinity corresponding to Type I cellulose, SEM showed a roughened fiber surface after alkaline treatment, and TGA indicated high thermal stability up to 250 °C. The goal is eco-friendly packaging by promoting agrowaste use. Further research should improve performance and scalability of cellulose-based bioplastics to meet industry needs and compete effectively with conventional plastics. Full article

Exposure of the plant cell wall to biotic and abiotic stresses results in structural and chemical changes. Russian wheat aphid (RWA) infestation severely damages wheat plants, releasing cell wall-degrading enzymes that compromise cell wall integrity. This study aims to elucidate the cell wall modifications in resistant wheat cultivars during RWA infestation. Three wheat cultivars with distinct resistance phenotypes to the RWA South African biotype 2 (RWASA2) were grown in the glasshouse. At the three-leaf stage, the seedlings were infested with RWASA 2 for 14 days. The leaf samples harvested at 2, 7, and 14 days post-infestation (dpi) were used to study cell wall modifications in the RWASA 2-infested cultivars, focusing on cellulose, hemicellulose, callose, and lignin contents. The results showed that post-RWASA2 infestation, the resistant Tugela-Dn5 significantly increased the hemicellulose content by 2.8- and 1.3-folds at 2 and 14 dpi, respectively, while the Tugela and Tugela-Dn1 significantly decreased the hemicellulose content at 2, 7, and 14 dpi. Tugela-Dn5 also increased the cellulose content by 1.4-fold and 2.2-fold at 7 and 14 dpi, respectively. The acid-soluble lignin content significantly increased in the infested Tugela-Dn5 compared to uninfested at 2 and 14 dpi, while it significantly decreased in Tugela and Tugela-Dn1. Callose levels also increased in all cultivars at 2 dpi, but only the infested Tugela-Dn5 exhibited an increase in callose content compared to the uninfested at 14 dpi. The extracted contents of the increased cellulose, hemicellulose, and lignin in Tugela-Dn5 were corroborated by FTIR analysis, which showed broad peaks at 3300 cm⁻¹ representing the OH functional group and inter- and intra-hydrogen bonds within the increased cellulose in Tugela-Dn5. No significant reduction of lignin peaks at 1600 to 1578. 99 cm⁻¹ assigned to the phenolic groups was observed in Tugela-Dn5. These findings place cell wall modifications at the centre of the wheat’s physiological resistance response to aphid infestation, particularly the reinforcement of the cell wall that persists for 14 dpi. Full article

The effects of thermal treatment on the changes in the chemical composition and higher heating values (HHV) of tropical hardwood meranti were investigated in a study. The samples of light red meranti wood (Shorea spp.) with dimensions of 20 mm × 100 mm × 700 mm were conditioned at 20 °C (control samples) and thermally treated at 160, 180, 200, and 220 °C. The chemical composition and HHV of control samples and thermally treated samples were evaluated. The chemical composition was measured using the procedures of Seifert, Wise, and ASTM. After thermal treatment, a significant reduction in holocellulose and hemicellulose content and an increase in extractives and lignin were observed. Consequently, we observed a rise in HHVs. HHV of thermally treated wood was strongly positively linearly correlated with lignin content (Pearson r = 0.9850, p < 0.001, R² = 0.9702, n = 15). Regression analysis showed that the model HHV = 0.1443(lig) + 16.012 is suitable for predicting the HHV of thermally treated wood, if the lignin content is known. Full article

Almond hulls and shells, the byproducts of the almond industry, were analyzed to assess their potential valorization pathways. Shells showed a higher content in lignin and polysaccharides, but very low levels of extractives and inorganics. Hull’s high polar extractives fraction showed poor phenolic preponderance and antioxidant activity, but high sugar and mineral contents, and its lipophilic extracts were highly enriched in triterpenes (from 73.5% to 91.3%), while shells presented more fatty acids (27.4% to 34.2%) and sterols (17.4% to 29.1%). Shells exhibited much higher S/G ratio (syringyl to guaiacyl units) in their lignin polymer (1.0 to 1.4), compared to hulls (0.5 to 0.6). After mineral analyses, hulls showed high amounts of potassium (3.7–4.9%). Fixed carbon content was similar for both materials, but shells showed a higher energetic content, ~20 MJ/kg. Finally, both hulls and pellets increased the water holding capacity (WHC) of the soil by 50%, when added in weight percentages of 6.25% (hulls) and 25% (pellets). With these results, the range of possibilities for these waste materials is exciting: shells could be used to obtain hemicellulose oligosaccharides, while hulls could be used in sugar extraction for biotransformation or as a soil amendment. Full article