Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030020

Authors: Annabell Eder Claus-Ekkehard Koukal Fabian Stauss Stefano Barbini Emmerich Haimer

Horsehair generated during seasonal coat shedding represents an underutilized biogenic by-product with potential for textile valorization. In this Communication, we present a first proof-of-concept investigation of the suitability of equine body hair as a raw material for nonwoven production. Hair samples collected during the spring shedding period (March–May) were analyzed for their morphology, fiber dimensions, elemental composition, lipid content, and processing behavior. Pretreatment methods included cleaning and washing, solvent-based degreasing using methyl tert-butyl ether (MTBE), and lipid extraction using supercritical CO2. Fiber processing trials were conducted using manual and industrial nonwoven formation techniques, followed by mechanical consolidation through needle punching and hydroentanglement. While the results demonstrate that horsehair can be processed into nonwoven structures, pure horsehair webs showed limited fiber cohesion and surface fiber shedding. Blended nonwovens containing Lyocell and sheep wool as well as multilayer structures were therefore produced and showed improved handling and reduced fiber release. In addition, preliminary supercritical CO2 extraction trials demonstrated the recovery of a substantial lipid-rich fraction, indicating the potential to combine extraction and subsequent fiber utilization within a preliminary cascade valorization strategy. Our study establishes the technical feasibility of this approach while identifying limitations requiring further investigation, particularly quantitative mechanical and functional characterization, optimization of fiber cohesion, chemical characterization of the recovered extract, and environmental and economic assessment.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030019

Authors: Xinchao Yang Chen Li Yuehui Liu Fang Wang Naxin Sun Yuanxiu Wang Chunjiang Ye Zhongzheng Wang

To realize the high-value valorization of cold-pressed walnut meal, walnut oligopeptides were fabricated via synchronous dual-enzyme hydrolysis combined with activated carbon decolorization and membrane separation purification. We optimized the overall preparation process and systematically characterized the products, including their amino acid profile, in vitro antioxidant capacity, cytoprotective effects against H2O2-triggered oxidative injury in PC12 cells, and regulatory activity toward acetylcholinesterase (AChE). The optimal hydrolysis conditions were identified as pH 10.0, total enzyme dosage of 11,000 U/g, a trypsin-to-alkaline protease ratio of 2.1:1, solid–liquid ratio of 1:26, temperature of 51 °C and reaction duration of 4 h, which produced a hydrolysis degree of 33.02%. The optimized decolorization parameters were pH 5.2, activated carbon dosage of 2.3%, treatment at 58 °C for 43 min, with a peptide recovery rate reaching 83.35%. Cold-pressed walnut meal is rich in glutamic acid, arginine and aspartic acid, which lay the molecular foundation for the bioactive properties of the derived oligopeptides. In vitro tests demonstrated that the oligopeptides possessed strong scavenging ability against hydroxyl, DPPH and superoxide anion radicals (clearance rates of 90.18%, 81.72% and 85.80%, respectively), and maintained 73.21% of antioxidant activity after simulated gastrointestinal digestion. Moreover, walnut oligopeptides at 0.8 mg/mL showed no cytotoxicity and afforded a 79.88% protective effect against oxidative damage. The peptides significantly boosted SOD and GSH-Px activities, lowered MDA accumulation, and strongly suppressed AChE activity, performing better than donepezil hydrochloride. This efficient, eco-friendly technique achieves high-value utilization of walnut processing by-products. The obtained oligopeptides possess great potential as natural antioxidants and neuroprotective ingredients for functional food development.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030018

Authors: Marília Gabriela Lopes Cavenaghi Giovana Correia de Assis Netto Ivaldir José Tamagno Junior Bruno Faccini Santoro Moisés Teles dos Santos

Brazil ranks among the world’s largest agricultural producers, generating substantial agro-industrial residues with significant potential for valorization in biorefinery systems. Comprehensive, updated data on the characterization, availability, and spatial distribution of major crops and their residues are essential for biomass conversion system design but remain lacking in the literature. This study presents a five-part contribution. First, a literature review mapped 534 articles, of which 91 were selected for full-text reading and 37 were retained in the final quantitative synthesis, to assess the generation, location, and availability of Brazil’s main agro-industrial residues and reveal research gaps and trends. Crop production rate was the most frequently reported variable, followed by energy generation potential and residue-to-product ratios; most studies addressed bioenergy applications, while economic and environmental aspects were rarely covered. Second, updated 2023 data estimated from 734.57 to 1168.64 million metric tons of agro-industrial residues generated in Brazil. Third, the work reviewed biomass processing routes, covering upstream (pretreatment and conversion) and downstream stages. Fourth, product yield data were compiled for the residues of seven of the eight assessed crops, standardized per 100 g of dry biomass, enabling cross-feedstock and cross-route comparisons not previously available in a consolidated dataset. Fifth, the study maps Brazilian bioenergy policy instruments against the governance dimensions required for coordinated biorefinery deployment, identifying fragmentation across ministries and priority recommendations for policy action. Although grounded in the Brazilian context, the methodological framework and yield dataset are transferable to other biomass-producing regions, supporting residue-based biorefinery design at different scales.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030017

Authors: Hamed M. El Mashad Abdolhossein Edalati Bor-Sen Chiou Zach McCaffrey Trung Cao William Hart-Cooper Ruihong Zhang Frank Mitloehner

The effects of pyrolysis temperature (400–500 °C) and time (30–90 min) on the yield and chemical and physical properties of biochar produced from almond and pistachio shells were studied using a fixed-bed pyrolyzer. Thermogravimetric analysis (TGA) was employed to characterize the kinetics of thermal degradation of the shells. This study compared the thermal behavior observed by TGA with biochar yields obtained from a fixed-bed pyrolyzer, providing insight into the agreement between laboratory-scale thermogravimetric measurements and fixed-bed pyrolysis performance. Fourier transform infrared spectroscopy (FTIR) was performed for each type of biochar. Results showed higher biochar yields from almond shells (35.0–41.3% dry basis) than from pistachio shells (26.8–36.7% dry basis). Shell type, pyrolysis temperature, pyrolysis time, and their interactions had significant effects on biochar yield. The Derivative Thermogravimetric (DTG) profiles showed distinct thermal decomposition patterns for almond and pistachio shells. Almond shells exhibited broader decomposition regions, while pistachio shells showed more distinct decomposition stages. FTIR analysis of both shell biochars indicated reduced O–H and oxygen-containing groups with increasing pyrolysis temperature and residence time, suggesting greater carbonization, aromatic enrichment, and formation of carbonaceous compounds. Greater biochar yields were obtained from the fixed-bed pyrolyzer than from TGA. A first-order kinetics model adequately described the thermal decomposition of both shell types. Apparent activation energies were 41.83–44.99 kJ mole−1 for almond shells and 58.19–63.58 kJ mole−1 for pistachio shells. Model validation showed a good agreement between the experimental and predicted conversion values. The results provide a basis for evaluating the potential of TGA-derived thermal behavior to inform biochar production conditions in fixed-bed pyrolysis.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030016

Authors: Lindsay Dorschner Pelcoq Fenosoa Tatiana Randremahitsimanana Asmina Chanfiou Amani Belaiba Lily Dubosquelle Sanae El Moudni El Alami Arash Jamali David Mathiron Catherine Sarazin Caroline Hadad Eric Husson

Horse manure is an abundant lignocellulosic feedstock with potential for circular biorefineries to diversify and upgrade the methane value chain. However, integrated fractionation strategies enabling the simultaneous valorization of both polysaccharides and lignin remain poorly explored. Here, we developed the Coffionic strategy, a closed-loop, green iono-organosolv fractionation combining, in a two-step, one-batch approach, the eco-acceptable ionic liquid 1-ethyl-3-methylimidazolium acetate and the food-grade solvent 2-methyltetrahydrofuran-3-one, with full solvent recovery and recycling. This strategy selectively recovered 70% w/w of the lignin from horse manure, yielding a Coffionic lignin fraction with a purity of 78% w/w and less than 2.5% w/w of residual sugars. The resulting polysaccharide-rich fraction showed enhanced enzymatic digestibility, achieving >99% cellulose conversion and increasing the biochemical methane potential by 17% compared with untreated horse manure. Coffionic lignin was further upgraded by enzymatic transesterification using immobilized Novozym435® in the same food-grade solvent employed for fractionation, yielding lignin esters compatible with PLA. Esterified lignin–PLA films reached a total surface energy significantly higher than neat PLA and unmodified lignin–PLA films. Overall, the Coffionic strategy provides an integrated and low-waste biorefinery route enabling the simultaneous production of biomethane and high-value lignin-based materials from horse manure.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030015

Authors: Yifei Wang Sudharshan Juntupally Keunje Yoo Hyunsu Kim Eunseok Lee Hyung-Sool Lee

Percolation-based dry anaerobic digestion (AD) is an attractive technology for treating high-solids food waste (FW) because it requires minimal water addition and eliminates the need for mechanical mixing. However, its methane production is often limited by slow hydrolysis and inefficient conversion of soluble intermediates. To overcome these limitations, this study developed a bioelectrochemical leach-bed reactor (BLBR) by integrating a microbial electrolysis cell with a percolation-based dry AD system to enhance methane production kinetics. Two 10-L reactors were operated in 10-day batch mode: an open-circuit control reactor and a bioelectrochemical reactor operated with applied voltages ranging from 0.3 to 1.2 V. Moderate voltage application significantly enhanced methane production, with the highest cumulative methane yield reaching 293 mL CH4/gVSadded at 0.9 V, representing a 47% increase over the control (199 mL CH4/gVSadded), while volatile solids removal remained comparable between treatments. Voltage-assisted operation promoted a rapid increase in soluble chemical oxygen demand (SCOD), followed by faster consumption than in the control. Similarly, acetate and propionate accumulated and were depleted earlier, indicating accelerated conversion of soluble intermediates. A transient butyrate concentration of 8.8 g COD/L was observed at 0.9 V, suggesting enhanced fermentative activity under moderate bioelectrochemical stimulation.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030014

Authors: Odilon Souza Leite-Barbosa Filipe Kayodè Felisberto dos Santos Erick Max Mourão Monteiro de Aguiar Clarissa Dias de Souza Valdir Florencio da Veiga-Junior

The transition from a linear to a circular economic model is critical for the sustainability of the Amazonian bioeconomy. Although Amazon nuts (internationally recognized as Brazil nuts, Bertholletia excelsa) represent a major natural bioresource, their production chain faces structural challenges, particularly concerning the underutilization and disposal of agro-industrial residues. This narrative review analyzes the Amazon nut market, processing technologies, and supply chain, with a specific focus on biomass valorization. By evaluating the recent literature across major scientific databases, this study maps the technological readiness and feasibility of integrating a circular economy model. We critically examine alternative technologies for transforming specific residues, particularly the woody fruit pods, hard seed shells, and oil press cakes, into value-added bioproducts. Key valorization routes discussed include protein concentrates and amino acid supplements from the press cake, cellulose nanocrystals and organic panels from the hard seed shell, biosolvents, and bioenergy/biochar generation via pyrolysis. The review concludes that while the current industry remains strictly focused on kernel commerce, transitioning toward a circular model appears technically promising, but its economic feasibility remains unconfirmed for most valorization pathways. However, successful industrial implementation requires overcoming logistical supply chain barriers and advancing the technology readiness levels of these valorization pathways.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030013

Authors: Arturo Coronado-Contreras Danitza Casas-Rodríguez Dulce W. González-Martínez Juan A. Ascacio-Valdes Thelma K. Morales-Martínez Raúl Rodríguez-Herrera Cynthia L. Barrera-Martínez Aidé Saenz-Galindo Leonardo Sepúlveda

Agro-industrial residues such as prickly pear peel represent an underutilized source of bioactive compounds. However, comparative evidence on green extraction versus biotransformation strategies remains limited. This study evaluated solid-state fermentation (SSF), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) for tannin recovery from Opuntia ficus-indica peel. SSF using Aspergillus niger significantly enhanced condensed tannins (>50 mg/g) and hydrolyzable tannins (~7 mg/g), outperforming UAE and MAE. This improvement was associated with fungal-mediated cell wall degradation and metabolic transformation. SSF extracts also showed superior antioxidant activity (DPPH, ABTS, and FRAP) and exclusive antimicrobial activity against Escherichia coli (4.5 mm inhibition zone). HPLC analysis revealed increased phenolic diversity, with rhamnetin as the predominant metabolite. These findings demonstrate that SSF is not only an extraction method but also a biotransformation strategy that enhances both the yield and functionality of phenolic compounds. This approach supports the sustainable valorization of agro-industrial residues within a circular bioeconomy framework.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2030012

Authors: Dalila Lopes José Luís Louzada Letícia Moreira Fábio Pereira Maria Emília Silva

Pinus pinaster Ait. forests have potential for resin tapping, a forestry activity that complements timber production and may increase the profitability of maritime pine stands. However, the viability of this co-production remains uncertain due to the potential effects of resin tapping on wood characteristics. The present study aimed to investigate the effects of resin tapping on the wood characteristics of maritime pine, in order to infer possible changes in wood quality, its utilisation, and, consequently, its value. The study was based on samples collected in Tresminas from resin-tapped trees (37.2 ± 6.0 years old and mean height of 15.8 ± 1.4 m) subjected to the traditional Portuguese resin tapping method for four consecutive years, and from non-resin-tapped trees (37.5 ± 8.9 years old and mean height of 14.1 ± 2.2 m). Samples were collected from different positions along the stem of resin-tapped trees (incision side, opposite side, and 50 cm above the last tapping incision) and compared with samples obtained from non-resin-tapped trees. Wood density, modulus of elasticity (MOE), modulus of rupture (MOR), extractives content, growth ring width and the number and area of resin ducts were evaluated. The effects of resin tapping on wood properties were assessed by comparing resin-tapped and non-resin-tapped trees, as well as different sampling positions within resin-tapped trees, using linear mixed-effects models. Mean comparisons were performed using Tukey’s test at a 95% significance level. No significant effects of resin tapping were observed on MOE or MOR between resin-tapped and non-resin-tapped trees. Wood from the incision side showed higher density (0.596 g·cm−3) and higher extractives content (7.49%). Resin-tapped trees produced a greater number of resin ducts after tapping; however, their area did not change. No significant differences were found in growth ring width between resin-tapped (1.75 mm) and non-resin-tapped trees (1.80 mm), although resin-tapped trees presented slightly narrower rings on average. Resin tapping in P. pinaster did not promote relevant changes in wood properties that would compromise its mechanical and physical performance. Although some alterations were detected, these were predominantly localised and restricted to the region adjacent to the tapping incision.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2020011

Authors: Ida Diribissakou Adama Ndao Said Elkoun Kokou Adjallé

Brown macroalgae are a promising substrate for alginate production, yet the conventional acid–alkali route raises environmental and quality concerns due to its high reagent inventory, large saline effluents, and partial depolymerization of the polymer backbone. To address these limitations, we evaluated five extraction strategies on a single Saccharina latissima feedstock: conventional acid–alkali extraction as the reference, enzymatic hydrolysis (HE), extrusion combined with enzymatic hydrolysis (Ex-HE), sonication combined with enzymatic hydrolysis (S-HE), and the sequential combination of extrusion, sonication, and enzymatic hydrolysis (Ex-S-HE). The optimized HE process achieved an alginate yield of 34.08% on dry biomass. This value exceeds the conventional benchmark of 31.08%. Hydrolysis time and biomass loading governed the yield. Enzyme dose showed no significant effect within the studied range. Sonication alone yielded 14.55% under surface-limited kinetics, driven exclusively by acoustic amplitude. Scale-up of HE to a 150 L pilot bioreactor recovered 43% of total soluble solids through lyophilization. Ethanol precipitation at the 5 L scale delivered 26.87% of purified alginate. The two metrics describe distinct end products. They represent complementary outputs of a cascade biorefinery rather than competing routes. The HE-derived alginate matches commercial standards by FTIR, TGA, and viscosity. Its M/G ratio is expected to fall within the published range for S. latissima alginate (1.4 to 1.8). Ethanol precipitation of brown algal hydrolysates typically yields products with 80 to 95% uronic acid content. Quantitative techno-economic and environmental analysis indicates substantial reductions in CO2-equivalent emissions and E-factor relative to the conventional route. Total cost becomes competitive when the cascade biorefinery is monetized through co-products such as mannitol, laminarin, and phlorotannins. These results position enzymatic hydrolysis as the most effective single-step strategy for alginate recovery from S. latissima. To our knowledge, this is the first study to couple face-centred central composite optimization of two pretreatment families on a single S. latissima biomass batch with a 30-fold pilot-scale validation from 5 L to 150 L and a comparative functional characterization of two recovery methods (ethanol precipitation and lyophilization).

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2020010

Authors: Krisnna Sousa Alves Tiago Guimarães Angélica de Cássia Oliveira Carneiro Ana Márcia Macedo Ladeira Carvalho Sebastião Renato Valverde Marcelo Moreira da Costa

Anatomical, chemical, and physical properties are critical for optimizing bamboo applications. This study evaluated the radial variability of these properties in four bamboo species (Guadua chacoensis, Dendrocalamus strictus, Bambusa nutans, and Dendrocalamus asper) to assess their potential as sustainable raw materials. Anatomical analysis revealed significant radial gradients: fiber wall thickness and lignin content peaked in the peripheral region (e.g., 30.40% lignin in D. strictus), while carbohydrate content was highest in the central region (69.15% in D. asper). Basic density varied radially, with the highest values in G. chacoensis (835 kg/m3) and B. nutans (858 kg/m3). Principal Component Analysis (PCA) identified density and chemical composition as key discriminators among species. Dendrocalamus strictus emerged as the most promising species for biochar production, exhibiting high gravimetric yield (31.14%), thermal stability, and a mesoporous structure (120.154 m2/g surface area). The biochar’s high elemental carbon (89.66%), calculated fixed carbon (84.97%), crystallinity index (30.16%), and low volatile content (6.83%) suggest potential for use as a soil conditioner for carbon sequestration, although direct agronomic validation (e.g., soil, plant, or microbial assays) is still required. A techno-economic assessment (TEA) demonstrated its commercial viability, projected a profit of approximately US$ 89/ton and US$ 1107/hectare per year under a 3-year rotation cycle, assuming a unified market price of US$ 120/ton. This estimate is preliminary and does not include sensitivity analysis, which is suggested for future work. This study underscores D. strictus as a dual-purpose resource, combining ecological benefits (e.g., soil enhancement) with economic feasibility, advancing sustainable agro-industrial applications of bamboo.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2020009

Authors: Md Mahfujul Islam Kundan Kumar Ming-Hsun Cheng Armando G. McDonald Ling Ding Yingqian Lin Maobing Tu

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.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2020008

Authors: Olumide Joseph Olubiyo Sungil Ferreira

The growing worldwide need for sustainable, high-quality protein sources has intensified interest in single-cell protein (SCP) production, particularly mycoproteins derived from filamentous fungi. This shift is further driven by global sustainability priorities articulated by regulatory bodies, which promote resource efficiency, waste valorization, and sustainable food systems. Despite their high carbohydrate potential, the agricultural sector generates vast quantities of starch-rich by-products. Examples include broken rice, cassava peels, potato waste, and cereal-processing residues, which remain largely underutilized and thereby contribute substantially to environmental pollution. This literature review examines the potential of starch-based agricultural by-products as low-cost, renewable feedstocks for fungal SCP production in support of the Sustainable Development Goals (SDGs). These by-products include broken rice, cassava peels, potato waste, and cereal processing residues, which remain largely underutilized despite their high carbohydrate content. Key topics include pretreatment strategies, fungal fermentation with Neurospora and Fusarium spp., and process optimization to maximize biomass yield and feedstock valorization. Life cycle assessments (LCAs) indicate reduced greenhouse gas emissions compared with conventional protein sources, highlighting the potential of starch residues in circular bioeconomy systems. Furthermore, considerations related to process design, environmental benefits, and techno-economic feasibility are evaluated in the context of converting starch residues into fungal protein. In summary, the evidence suggests that valorizing starch by-products for mycoprotein fermentation, used both as a protein alternative and as an ingredient, represents a promising strategy to reduce waste management and production costs and support global food sustainability.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2020007

Authors: Tomoyuki Honda

Japan’s import market for wood pellets has expanded rapidly since the introduction of the feed-in tariff (FIT) scheme in 2012, with imports exceeding six million tonnes in 2024, positioning Japan as the world’s second-largest wood pellet importer. Despite this expansion, empirical evidence on its demand structure remains limited. This study employs a Dynamic Linear Approximate Almost Ideal Demand System (Dynamic LA-AIDS) model incorporating demand inertia stemming from long-term fuel supply contracts to analyze Japan’s wood pellet import demand from 2012Q1 to 2025Q3. The results reveal a distinct two-tiered structure: North American pellets behave as a strategic necessity, exhibiting price-inelastic demand and a tendency toward a stable long-run procurement pattern following price and expenditure shocks, suggesting procurement practices that prioritize supply security under long-term contracts. In contrast, Vietnamese pellets behave as a price-sensitive commodity, displaying price-elastic demand and relatively sustained responsiveness following such shocks. These results indicate a dual procurement strategy under the FIT scheme that balances stability and cost flexibility. Importantly, the Japanese demand structure differs from the more uniformly price-inelastic patterns observed in the EU and South Korean markets, providing new insights into how institutional frameworks shape biomass allocation and market responsiveness in renewable energy systems.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2020006

Authors: Máire Nic an Bhaird Laoise Ní Chléirigh Thomas P. Curran

Children are largely absent from circular economy and bioeconomy research, limiting opportunities for early development of systems thinking, sustainability competencies, and inclusive knowledge production. This paper presents a qualitative case study of the Horizon 2020 AgroCycle project (2016–2019), examining how primary school children were engaged as co-researchers through a transdisciplinary, participatory model. Analysis draws on project deliverables, educational resources, workshop records, internal reports, and dissemination materials. The study shows how children and adult co-researchers explored waste valorisation, bioresource transformation, and biobased material innovation in Irish schools. Valorisation in the context of the bioeconomy is the process of converting residues from farming, food, forestry and marine sources into high-value products such as biofertilisers, biofuels and biochemicals. It situates AgroCycle within European sustainability policy, highlighting its influence on subsequent initiatives, including Horizon Europe BioBeo and BiOrbic, Research Ireland’s Centre for Bioeconomy. By combining qualitative case study methodology with reflective practitioner analysis, the paper demonstrates how child-centred, transdisciplinary research can enhance sustainability education, support SDG-aligned competencies, and promote inclusive approaches to circular economy and bioeconomy transitions.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2020005

Authors: Aline De Oliveira Campos Peter James Strong

Ganoderma mushrooms produce bioactive metabolites with therapeutic potential, yet their tissue-level distribution is not well characterized. This study quantified triterpenoids, β-glucans, and phenolics across six anatomical sections of fruiting bodies from five wild Ganoderma species. Twenty-six triterpenoids were identified. Laccate species showed thicker context tissue enriched in ganoderic and lucidenic acids, resembling the chemotype of G. lucidum. Matte species displayed greater triterpenoid diversity, including elfvingic, applanoxidic, and ganoderenic analogues. Maximum contents reached 3.5% triterpenoids, 34.3% β-glucans, 20.8 mg TE·g−1 (ABTS), 175.2 µmol Fe2+·g−1 (FRAP), and 23.5 mg GAE·g−1 phenolics. Triterpenoids and phenolics were highest in outer cap tissues, while β-glucans predominated in context layers. These patterns reflect functional tissue roles and developmental variation. The tissue distribution of metabolites in wild Ganoderma presented here identifies surface tissues as a major source of triterpenoids and phenolics, and internal tissues as a source of β-glucans. These traits represent selection targets for extraction and selective breeding to produce strains with thicker context tissue and higher triterpenoid and β-glucan yields.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2010004

Authors: Mark Korang Yeboah Dirk Söffker

Growing global energy demand and concerns over climate change and fossil fuel depletion have increased interest in sustainable bioproducts such as ethanol. Unlike first-generation (1G) ethanol derived from food crops (e.g., corn), second-generation (2G) ethanol is produced from lignocellulosic biomass, an abundant non-food resource that addresses key sustainability concerns. Consolidated bioprocessing (CBP) integrates enzyme production, hydrolysis, and fermentation into a single step, using either microbial consortia or engineered microorganisms, thereby simplifying the process and potentially reducing costs compared with separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). However, CBP systems are complex due to dynamic interactions among microbial communities, metabolic pathways, and process conditions. Addressing this complexity requires modeling approaches that capture nonlinear relationships and support robust process optimization. Machine learning (ML)-based models offer data-driven tools to represent complex bioprocess dynamics, improve predictive accuracy, and optimize bioproduct formation, thereby supporting progress toward commercial viability. Although CBP can be applied to a range of bioproducts, this review primarily focuses on lignocellulosic ethanol and closely related biofuels. The review provides a comprehensive overview of key CBP processes, the current state of CBP modeling, major limitations, and the emerging role of ML in addressing modeling challenges. It summarizes recent modeling techniques for CBP, including polynomial models and response surface methodologies, and discusses regression and neural network approaches in detail. Both first-principles and data-driven modeling strategies are considered, highlighting advances that can improve the scalability and efficiency of CBP for bioproduction. Overall, this review offers perspectives on modeling-enabled pathways for utilizing low-cost lignocellulosic biomass in sustainable bioprocessing.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2010003

Authors: Jovale Vincent Tongco Armando G. McDonald

Lignocellulosic bio-based materials, such as wood, biocomposites, and natural fibers, exhibit desirable structural properties. This comprehensive review emphasizes the foundational and latest advancements in bioinspired improvement strategies, such as direct mineralization, biomineralization, lignocellulosic nanomaterials, protein-based treatments, and metal-chelating processes. Significant focus was placed on biomimetics, emulating natural protective mechanisms, with discussions on relevant topics including hierarchical mineral deposition, free-radical formation and quenching, and selective metal ion binding, and relating them to lignocellulosic bio-based material property improvements, particularly against fire and fungi. This review evaluates the effectiveness of different bioinspired processes: mineralized and biomineralized composites improve thermal stability, nanocellulose and lignin nanoparticles provide physical, thermal, and chemical barriers, proteins offer biochemical inhibition and mineral templating, and chelators interfere with fungal oxidative pathways while simultaneously improving fire retardancy through selective binding with metal ions. Synergistic approaches integrating various mechanisms could potentially lead to long-lasting and multifunctional protection. This review also highlights the research gaps, challenges, and potential for future applications.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2010002

Authors: Salomeh Chegini Abdul Razak Mohamed Sikkander Mehran Masoudi Homeira Ekhtari Elham Mojaver Hirad Jafari

Biodegradable waste is commonly treated as a problem to be managed, but it can be a valuable resource when considered within a circular bioeconomy perspective. This article develops a practical and systems-based frame work for integrating biodegradable waste, ranging from municipal food scraps to wastewater biosolids, into valuable resources. It explores real-world strategies for transforming waste into value-added products, including composting, anaerobic digestion, biochemical conversion, and the creation of bio-based materials. The review also highlights key drivers and barriers, including technical, regulatory, and social factors, which shape the feasibility and impact of circular solutions. A visual model illustrates the full cycle, from identifying waste streams to reintegrating recovered resources. The paper also highlights case studies from Toronto, Milan and Brazil as examples of successful implementation. Overall, this paper emphasizes a pragmatic yet regenerative shift toward organic resource recovery aligned with sustainability and decarbonization goals.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod2010001

Authors: Kgodiso J. Rabapane Charles Rashama Tonderayi S. Matambo

Sugarcane bagasse (SCB) is a lignocellulosic byproduct with low biodegradability, limiting its potential for biological processes such as biogas production. The objective of this study was to evaluate whether a short-term biological pretreatment with the cellulolytic bacterium Proteus mirabilis KC94 could enhance SCB hydrolysis, improve nutrient balance, and increase biomethane potential (BMP). Three treatments were compared: untreated bagasse (UB), sterilized bagasse (SB), and KC94-pretreated bagasse (PB). Glucose release was highest in PB (61.83 ± 0.8 mg/mL), indicating enhanced cellulose degradation in PB relative to UB (53.19 ± 0.9 mg/mL) and SB (44.00 ± 0.5 mg/mL). Elemental analysis revealed a more balanced nutrient profile in PB, characterized by optimal carbon and nitrogen levels, and reduced sulfur content, indicating microbial assimilation and potential biological desulfurization. Scanning electron microscopy revealed pronounced structural disruption, increased porosity, and fiber delamination in PB, confirming the efficacy of KC94-mediated lignocellulosic pretreatment. BMP assays conducted over a 31-day incubation period revealed that PB produced the highest cumulative methane yield (99 ± 0.7 mL CH4/g VS), representing 19% and 25% increases over UB and SB, respectively. PB biomethanation was also faster compared to the other two substrates. These findings demonstrate the novelty of a 5-day bacterial pretreatment strategy, which significantly improves lignocellulosic hydrolysis and methane yield. Specifically, P. mirabilis KC94 pretreatment increased glucose release by 16–40% and cumulative methane yield by 19–25% compared to untreated and sterilized controls. This cost-effective and environmentally friendly approach highlights the potential of P. mirabilis KC94 to valorize sugarcane bagasse, advancing sustainable energy recovery and circular bioeconomy practices.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1020009

Authors: Óscar González-Prieto David Casais Goimil Luis Ortiz Torres

Wood is a primary bioproduct widely utilized as timber in construction and carpentry. Characterization of its properties, particularly moisture response, is essential for industrial performance. The Fiber Saturation Point (FSP) influences the dimensional stability and efficiency of industrial processes such as drying. This study determines the maximum dimensional variation and the FSP of Eucalyptus nitens solid wood from plantations in Northwestern Spain, studying 354 specimens of 20 × 20 × 50 mm. Mean and median values were calculated considering and omitting outliers. Additionally, a graphical FSP value was obtained by applying the statistical theory of the center of gravity, defined as the intersection of lines derived from the two-dimensional data distribution. For maximum dimensional variation, the analysis yielded mean values of 5.2% [±1.53] and 11.2% [±2.84] and medians of 4.8% and 10.4%, in radial and tangential directions, respectively. The mean FSP was 29.9% [±7.95], the median 28.9%, and the graphical estimate 30.8%. Establishing the FSP defines the critical moisture threshold at which significant changes in physical and mechanical properties, as well as dimensional alterations, occur in this bioresource, particularly for its use as a bioproduct in carpentry and construction or for industrial wood drying.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1020008

Authors: Raj Kumar Thapa Bijaya Kumar Uprety R. J. Neil Emery Scott C. Farrow

Fatty acid desaturase 12 (FAD12) is a key enzyme in fatty acid biosynthesis, responsible for converting oleic acid to linoleic acid through desaturase activity. Euglena gracilis (Euglena) is an emerging platform for the industrial production of various metabolites, including lipids. However, a comprehensive understanding of Euglena’s fatty acid biosynthesis pathways remains incomplete, posing a significant barrier to the commercialization of Euglena bioproducts. To address this gap, we employed a bioinformatics approach to identify a Euglena gracilis FAD12 (Eg FAD12). We analyzed the evolutionary relationship of Eg FAD12 with its homologs from other organisms and revealed that the three canonical histidine box motifs are conserved among FAD12s. To characterize EgFAD12, we cloned it into the pEAQ-hyperstrans vector and overexpressed it in Nicotiana benthamiana to take advantage of its endogenous fatty acid pool, which could act as a substrate. The heterologous expression of FAD12 in N. benthamiana led to an increased linoleic acid content, demonstrating the suspected desaturase activity. To further confirm the function of Eg FAD12, we performed CRISPR-Cas9-mediated knockout of Eg FAD12 in Euglena, which resulted in a drastic reduction in linoleic acid (C18:2) without compromising biomass yield or lipid content. This work advances our understanding of fatty acid biosynthesis in Euglena and will aid in its adoption as a platform for producing customized lipids.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1020007

Authors: Jaden Storrer Tansley M. Mazurkiewicz Bodee Hancock Ronald C. Sims

Methane is a potent greenhouse gas that requires its emissions to be mitigated. A significant source for methane emissions is in the form of the biogas that is produced from anaerobic digestion in wastewater reclamation and landfill facilities. Biogas has a high valorization potential in the form of its bioconversion into ectoines, an active ingredient in skin care products, by halotolerant alkaliphilic methanotrophs. Cultures of Methylotuvimicrobium alcaliphilum 20Z were grown in bench scale stirred-tank reactors to determine factors to improve methane uptake and removal. Tangential flow filtration was also implemented for a bio-milking method to recover ectoine from culture media. Methane uptake and reactor productivity increased, with a temperature of 28 °C compared with 21 °C. Decreasing the methane gas bubble diameter by decreasing the sparger pore size from 1 mm to 0.5 µm significantly improved methane removal and reactor productivity by increasing mass transfer. Premixing methane and air before sparging into the reactor saw a higher removal of methane, while sparging methane and air separately created an increase in reactor productivity. Maximum methane removal efficiency was observed to be 70.56% ± 0.54 which translated to a CH4-EC of 93.82 ± 3.36 g CH4 m−3 h−1. Maximum ectoine yields was observed to be 0.579 mg ectoine L−1 h−1.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1020006

Authors: Tayná Rebonato Oliveira Álison Moreira da Silva Gabriela Fontes Mayrinck Cupertino Fabíola Martins Delatorre Gabriela Aguiar Amorim Marina Passos de Souza José Otávio Brito Ananias Francisco Dias Júnior

Spontaneous combustion of charcoal is still not fully understood, generating uncertainties among producers, regulatory agencies, and the scientific community. This study evaluated the influence of final pyrolysis temperature (350, 450, 550, and 650 °C) on the properties of Eucalyptus spp. charcoal and its relation to ignition behavior. Gravimetric yield, proximate composition, calorific value, and ignition temperature were determined. Charcoal yield decreased by 31% between 350 °C and 650 °C. Fixed carbon content increased from ~65% to ~93%, accompanied by a reduction in volatile matter (~35% to ~6%) and a corresponding rise in calorific value. Step-heating experiments, conducted in a furnace with infrared camera monitoring, showed that ignition temperature increased from ~273 °C in charcoal produced at 350 °C to ~424 °C in charcoal produced at 650 °C. Strong correlations indicated that higher fixed carbon and lower volatile matter contents are directly associated with higher ignition temperatures. These results demonstrate that increasing the final pyrolysis temperature improves both the thermal stability and the energy quality of charcoal, although at the expense of gravimetric yield. Since the methodology was based on forced heating rather than spontaneous combustion under near-ambient conditions, complementary tests are required to evaluate spontaneous combustion propensity. Overall, the findings provide practical insights to balance yield, quality, and safety while reinforcing the importance of standardized assessment protocols to ensure safer storage and transport of charcoal.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1010005

Authors: Shariat Mobasser Tosin O. Olanrewaju Chad T. Jafvert Cliff Johnston Abigail S. Engelberth

The growing challenge of managing end-of-life creosote-treated railroad ties, along with the increasing demand for effective water treatment solutions, has highlighted the potential of converting railroad tie biomass into functional biochar through pyrolysis. Pyrolysis temperatures ranging from 250 °C to 700 °C were evaluated to determine their influence on biochar yield, physicochemical properties, and adsorption performance for nitrate and phosphate. The findings revealed that increasing pyrolysis temperature enhanced biochar surface area and porosity, reaching 454.9 m2/g at 700 °C. Elemental analyses showed maximum carbonization at 550 °C, with carbon content peaking at 80%, reflecting the development of more stable aromatic structures. SEM and FTIR analyses confirmed these structural changes, including the emergence of extensive pore networks and aromatic frameworks. Biochar produced at 600 °C demonstrated high nitrate (80%) and phosphate (79%) removal efficiencies, following Freundlich isotherm models. Magnesium-modified biochar further improved nitrate adsorption, reaching 90% removal at 5 ppm. Importantly, polycyclic aromatic hydrocarbons in the biochar decreased significantly at higher temperatures, ensuring environmental safety. This work demonstrates the dual environmental benefits of converting hazardous railroad tie waste into value-added biochar for nutrient removal in water treatment applications, offering a sustainable and scalable solution for circular waste management.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1010004

Authors: Davis R. Haag Phillip E. Heck Ronald C. Sims

Filtrate from dewatering anaerobically digested biosolids is a side-stream of wastewater treatment that contains high concentrations of nitrogen and phosphorus compounds that can serve as nutrients for cultivating microalgae biomass as biofilms for bioproduct production at Water Resource Recovery Facilities (WRRFs). One system used to cultivate attached microalgae biofilms is the rotating algal biofilm reactor (RABR). A pilot RABR with 72 m2 growth surface area, 11.5 m2 footprint area, and a liquid volume of 11,500 L was operated in an outdoor environment at the largest WRRF in Utah, U.S.A, the Central Valley Water Reclamation Facility (CVWRF). The configuration of the RABR was altered from the previous configuration with regard to temperature and duty cycle with the goal to maximize biomass productivity. Results included an increase in dry biomass productivity on a footprint basis from 8.8 g/m2/day to 26.8 g/m2/day (205%) while power requirements changed from 28.3 W to 91 W. The increase in biomass productivity has direct benefits for bioproducts including bioplastic, biofertilizer, and the extraction of lipids for conversion to biofuels.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1010003

Authors: Monirul Islam Miskat Aditta Chowdhury Sadiq M. Sait Rabiul Islam

Due to the ever-increasing energy demand, Algeria’s sustainable energy crisis is a significant problem. Plant and crop residues can be a solution to this problem if they are used for bioethanol production, a viable alternative to fossil fuels. This study explores the potential of existing agricultural crop residues to overcome the sustainable energy crisis in Algeria. Agricultural residues such as cereals, roots and tubers, pulses, oil crops, vegetables, and fruits have great potential to solve the problem. The agricultural residues that are normally wasted can be utilized to produce bioethanol, which provides sustainable energy and also help to obtain a clean environment. It has been found that 1.65 million tons of bioethanol can be produced from Algeria’s available residues, which is equivalent to 44.10 petajoule of energy. Cereal and fruit residues contribute to most bioethanol generation, about 47.22% and 23.38%, respectively. In addition, bioethanol generated from residue can be used in Algeria’s transportation sector. Considering Algeria’s current energy condition, gasoline blended with ethanol such as E10 and E5 can be used in Algerian vehicles since no modification of vehicles is needed for utilizing these fuels. Research indicates that lignocellulosic biomass sources in Algeria, such as Alfa, olive pomace, and cereal straw, could provide up to 0.67 million tons of oil equivalent (Mtoe), representing approximately 4.37% of the energy consumption of the transport sector in Algeria. Algeria has the potential to produce up to 73.5 Mtoe and 57.9 Mtoe of renewable energy utilizing the energy crops. This study will also encourage relevant policymakers to develop sustainable energy policies that will enhance the renewable energy share in Algerian energy dynamics.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1010002

Authors: Amir Sadeghpour Moein Javid Sowmya Koduru Sirwan Babaei Eric C. Brevik

Heavy metals (HMs) including cadmium (Cd), lead (Pb), arsenic (As), zinc (Zn), copper (Cu), chromium (Cr), and nickel (Ni) pose significant challenges to bioenergy crop production due to their persistence, toxicity, and bioaccumulation in soils and plants. This study not only summarizes the mechanisms of HM absorption, translocation, and accumulation in bioenergy crops, but also critically assesses their impact on crop development, biomass quality, and biorefinery processes. Heavy metals disrupt key physiological processes and modify lignocellulosic composition, which is important for biofuel and biogas production. Global soil contamination from sources like industrial emissions, mining, and agricultural activities exacerbates these problems, posing a threat to both energy security and environmental sustainability. Sustainable management strategies, including phytoremediation, microbial bioremediation, soil amendments, and genetic engineering, are explored to mitigate HM effects while enhancing crop resilience. This review emphasizes the importance of integrating techniques to balance bioenergy production with environmental and human health and safety, including the use of HM-tolerant crop varieties, enhanced biorefinery processes, and robust policy frameworks. Future research should focus on developing scalable remediation technologies and interdisciplinary solutions that align with the United Nations’ Sustainable Development Goals and meet global bioenergy needs.

Bioresources and Bioproducts doi: 10.3390/bioresourbioprod1010001

Authors: Ronald C. Sims

Greetings to the bioresource and bioproducts community! I will serve as the Editor-in-Chief to collaborate with you as we promote the aims and scope of this new MDPI journal [...]