Bioresource Technology最新文献

Camellia oleifera shell (COS), a lignin- and hemicellulose-rich cultivation byproduct, offers significant potential for resource extraction. In this study, we developed an integrated biorefinery approach using mild metal chloride-catalyzed hydrothermal pretreatment to vaporize COS waste. Under optimized conditions (0.03 M AlCl₃, 170 °C, 60 min), hemicellulose-rich COS was selectively depolymerized into xylo-oligosaccharides (XOS) with a yield of 49.8 %. This efficient Lewis acid-catalyzed method produced high XOS yields and cellulose- and lignin-enriched solid residues. Compared to untreated samples, these residues, with reduced hemicellulose content, yielded hard carbon with increased interlayer spacing and closed pore structures, exhibiting superior sodium storage ability. This approach contrasts with traditional enzymatic hydrolysis and fermentation pathways. The hard carbon anode was incorporated into sodium-ion batteries, demonstrating practical feasibility with an initial reversible capacity (IRC) of 348 mAh g^-1, an initial coulombic efficiency (ICE) of 70.5 %, and capacity retention of 91.7 % after 100 cycles. This dual-product approach maximizes COS utilization and synergizes renewable chemical production with advanced energy storage, highlighting the unique advantages of our approach to XOS synthesis and material optimization, showcasing a clear advantage over existing single-product pathways.

On-demand electricity generation from biogas can be achieved through variable feeding regimes using easily degradable substrates, such as sugar beet. However, such substrates pose a high risk of foam formation in anaerobic digesters. This study aimed to identify foam-causing compounds in anaerobic digestion of sugar beet silage and to evaluate effective countermeasures. Pectin was identified as primary contributor to foaming during anaerobic digestion of sugar beet silage, while saponins had no effect. Pectinase pre-treatment of sugar beet silage reduced foaming by 30%. Furthermore, the antifoaming effect of seven vegetable oils was compared. Sunflower oil showed the highest foam suppression efficacy, while soybean oil had almost no effect. The acid number of vegetable oils, reflecting the content of free fatty acids, correlated most strongly with their antifoaming performance. These findings show practical strategies for effective foam control during anaerobic digestion of sugar beet silage, enabling flexible feeding for on-demand biogas production.

For the design of biomass gasification it is beneficial to have models which can predict the composition of gas products for a wide range of different biomass feedstocks. Complex machine learning models (e.g. neural networks and tree-based methods) are now being used for this purpose which are difficult to reproduce with large numbers of parameters involved. In this study the potential for higher order polynomials is investigated for the modelling of bubbling fluidised bed gasification. To reduce the number of parameters and to avoid over-fitting Least Absolute Shrinkage and Selection Operator (LASSO) regularisation is used. This is a novel application of high order polynomial regression with regularisation which allows the prediction of hydrogen composition with coefficient of performance of 0.9228 and only 85 fitted parameters. The next best existing methods give coefficients of performance of 0.8823 and 0.868 but require 261 parameters and more than 1000 parameters respectively. So this polynomial approach is shown to give accurate model prediction with simpler model equations.

Hydrothermal humification (HTH) of biomass is a promising approach to address the depletion of soil organic matter. However, the HTH products derived from lignocellulose are limited by low nutrient availability and conversion efficiency. In this study, four nitrogen-containing additives were used to produce nitrogen-rich artificial humic acids (AHA) from crop waste. The addition of urea, ammonium chloride, ammonium sulfate, and ammonium dihydrogen phosphate at 180 °C for 1 h significantly improved both the yield and quality of AHA. Optimal conditions were achieved using ammonium sulfate at a carbon-to-nitrogen ratio of 5, resulting in an impressive AHA yield of 40.75 ± 3.99 wt% and a nitrogen content of 3.54 %, closely resembling naturally formed humic acids. This represented a 38.27 % increase in yield and a 30.44 % increase in nitrogen content compared to the control. Moreover, 5NS-AHA exhibited reduced aromaticity, increased oxygen-containing functional groups, and enhanced functionality through the regulation of aliphatic and aromatic carbon structures. The concentration of furfural in the hydrothermal aqueous phase reduced from 43.48 % to 29.85 %. Ammonium sulfate optimized the HTH pathway through synergistic mechanisms involving acid-catalyzed oxidation, nitrogenated condensation, and aromatic condensation. This work provides a visible pathway for producing nitrogen slow-release AHA fertilizers from agricultural waste.

Efficient delignification remains a critical technological bottleneck hindering the valorization of plant cell wall resources. Plant cell walls are dynamic, spatially heterogeneous networks characterized by a highly interconnected physical architecture and complex chemical composition. In-situ visualization of delignification dynamics at the cell scale, coupled with a quantitative understanding of cell-specific delignification kinetics, provide a powerful approach for a deeper understanding of the delignification process. In this study, Confocal Raman microscopy mapping was employed to obtain lignin content and visualize the in-situ delignification process in different tissues and cells from rice stem, including parenchyma, sclerenchyma, protoxylem, vascular bundle sheath, epidermis, metaxylem, and external vascular bundle. Results revealed pronounced cell-type-dependent delignification responses, further supporting the concept that recalcitrance is not solely determined by lignin content per se. Furthermore, this study established, for the first time, the delignification kinetic models for these distinct tissues and cells, providing a quantitative framework for describing lignin content dynamics during acidified sodium chlorite delignification process. This study offers a valuable approach for understanding and optimizing cell-type-specific responses during the implementation of delignification strategies.

Agri-food waste, which includes organic materials discarded throughout the food supply chain from agricultural production and post-harvest handling to processing, distribution, and consumption, poses significant environmental and economic challenges due to resource underutilization and disposal issues. However, the valorization of these residues into value-added products, particularly resistant starch (RS), offers a sustainable solution. RS, a non-digestible carbohydrate with prebiotic properties, provides numerous health benefits, including improved gut health, blood sugar regulation, and enhanced satiety. Various studies have explored innovative methods for RS extraction from agricultural by-products such as potato peels, rice bran, banana peels, and chestnut starch. Techniques such as enzymatic hydrolysis, ultrasound-assisted extraction, and thermal processing have demonstrated high efficiency in producing RS while maintaining its functional properties. Additionally, advancements in artificial intelligence (AI), big data, and machine learning are playing a crucial role in optimizing waste valorization processes. AI-driven technologies enable precise classification and separation of food waste, improving the efficiency of extraction and processing techniques. The integration of smart systems, such as IoT-based waste classification, further enhances resource recovery. As research and technological advancements continue, the large-scale application of these sustainable extraction and processing methods is expected to support a circular economy, reduce food waste, and provide functional food ingredients for the food industry.

This study comparatively assessed algal-bacterial granular sludge (ABGS) decontamination performance and microbial community mechanisms under two cultivation modes: flocculated sludge transformed into ABGS (AS_ABGS) and aerobic granular sludge transformed into ABGS (AGS_ABGS). The results indicated that, AS_ABGS achieved superior pollutant removal (COD: 92.2 %, TN: 82.1 %, TP: 61.5 %) versus AGS_ABGS (COD: 96.3 %, TN: 75.1 %, TP: 53.3 %). Microbial community analysis revealed deterministic assembly dominated AS_ABGS, narrowing niches, and enhancing functional specialization of N/P-removing taxa. AS_ABGS exhibited higher modularity, robustness, and stronger positive algal-bacterial interactions (52.32 %). Conversely, stochastic assembly in AGS_ABGS yielded weaker interactions (50.45 %). Metagenomics confirmed AS_ABGS enriched N/P metabolic genes (amo, acc) may be driven by Thauera, Micavibrio, and Aquisediminimonas, while AGS_ABGS favored Amaricoccus and Rhodovulum but showed lower N/P gene abundance. This study highlights the effect of algal-bacterial ecological interactions mediated by functional genes on the decontamination efficiency of ABGS and provides valuable insights for advancing this method.

Biochar has potential applications in steelmaking processes, but faces technical challenges such as low material density, high alkali content, and high reactivity compared to coal. This study explores converting the solid residue, following hydrothermal pretreatment-steam explosion (HTP-SE) of Miscanthus and other biomass feedstocks, into biochar to facilitate the replacement of coal in blast furnace and electric arc furnace operations. It is the first to demonstrate the enhanced combustion characteristics of pretreated fibre and the compatibility of the biochar for use in steelmaking. Biomass from birch, miscanthus, wheat straw, both untreated and pretreated, was evaluated. HTP-SE was conducted at 192 °C and 1.3 MPa, conditions aligned with hemicellulose extraction for application in biobased products. Biochars were produced at temperatures ranging from 300 °C to 550 °C. HTP-SE increased the carbon, hydrogen, and energy content by approximately 10%, 8%, and up to 5 MJ/kg, respectively, while reducing ash quantity by up to 45%. In addition, it reduced the alkali and phosphorus content from the solid fraction into aqueous phase. Gas analysis indicated that HTP-SE enhanced the energy content of pyrolysis syngas. Thermogravimetric studies revealed that pretreated biochars exhibited significantly lower reactivity with carbon dioxide compared to untreated counterparts, approaching the reactivity of coal. This was attributed to increased aromaticity, C=C bonding, cross-linkages enriching lignin and by the removal of hemicellulose through HTP-SE. Overall, the upgraded biochar addresses key limitations of conventional biochar and shows strong potential as a substitute to replace injection coal entirely in both blast and electric arc furnaces.