Search Results (1,019)

Lignocellulosic agro-forestry residues (LARs), such as rice straw, sugarcane bagasse, and wood wastes, are abundant and low-cost feedstocks for polyhydroxyalkanoate (PHA) bioplastics. However, their complex cellulose–hemicellulose–lignin matrix requires integrated valorization strategies. This review presents a dual-framework approach: “pretreatment–co-substrate compatibility” and “pretreatment–microbial platform matching”, to align advanced pretreatment methods (including deacetylation–microwave integration, deep eutectic solvents, and non-sterilized lignin recovery) with engineered or extremophilic microbial hosts. A “metabolic interaction” perspective on co-substrate fermentation, encompassing dynamic carbon flux allocation, synthetic consortia cooperation, and one-pot process coupling, is used to elevate PHA titers and tailor copolymer composition. In addition, we synthesize comprehensive kinetic analyses from the literature that elucidate microbial growth, substrate consumption, and dynamic carbon flux allocation under feast–famine conditions, thereby informing process optimization and scalability. Microbial platforms are reclassified as broad-substrate, process-compatible, or product-customized categories to emphasize adaptive evolution, CRISPR-guided precision design, and consortia engineering. Finally, next-generation techno-economic analyses, embracing multi-product integration, regional adaptation, and carbon-efficiency metrics, are surveyed to chart viable paths for scaling LAR-to-PHA into circular bioeconomy manufacturing. Full article

Three-dimensional concrete printing (3DCP) is rapidly emerging as a transformative construction technology, enabling formwork-free fabrication, geometric flexibility, and reduced labour. However, the lack of conventional reinforcement and the strict requirements for fresh and hardened properties present significant challenges. Fibre reinforcement and supplementary cementitious materials (SCMs), such as ground granulated blast furnace slag (GGBS), offer pathways to enhance printability while mitigating environmental impact. This study investigates the combined effect of natural cellulose microfibres and silica fume on the rheological, mechanical, and sustainability performance of 3D-printable mortars. Six mixes were prepared with 50% GGBS, 45% cement, and 5% silica fume, incorporating fibre dosages from 0% to 1%. Results showed that a 0.5% fibre dosage provided the most favourable balance. At this dosage, static yield stress increased to 9.35 Pa and thixotropy reached 8623 mPa·s, enhancing structuration for shape retention. Plastic viscosity remained stable at 4–5 Pa·s, ensuring adequate extrusion performance. Higher fibre dosages (≥0.75%) caused a significant increase in rheological resistance, with static yield stress reaching 208 Pa and thixotropy 135,342 mPa·s. This resulted in excessive structuration, fibre clustering, and poor extrudability. Compressive strength was achieved at 109.10 MPa (92% of silica fume-only mix) with 0.5% fibre. In comparison, flexural strength was 13.20 MPa at 0.5% fibre content and reduced gradually to 12.29 MPa at 1% fibre due to weak fibre–matrix bonding and porosity. Sustainability analysis confirmed that using 50% GGBS and 5% silica fume reduced embodied carbon compared to a 100% cement mix. This study also demonstrated that cellulose microfibres at 0.25–0.5% are optimal for balancing fresh properties, mechanical strength, and sustainability in 3D-printed mortars. Full article

Objective: This article investigated the structural characteristics, powder properties, and performance variations of co-processed pregelatinized starch (PS) and microcrystalline cellulose (MCC) at varying ratios. Methods: Scanning Electron Microscopy (SEM) revealed the embedding of MCC within the PS matrix. Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis indicated no chemical interaction between the starch and MCC during processing. The physical properties of the co-processed materials were evaluated using multiple indicators, such as the Carr index, and their properties in pharmaceutical applications were evaluated using multiple indicators, such as tensile strength and dilution capacity. Results: The absence of new chemical substances during co-processing, as confirmed by FTIR/XRD analyses, coupled with SEM evidence of a physically interlocked MCC-PS architecture, conclusively demonstrates that structural reorganization occurred via physical mechanisms. An increase in the MCC proportion enhanced the tensile strength of the co-processed material while decreasing the Carr’s index, particle size, tapped density, bulk density, swelling, and water-soluble content. A co-processed sample (PS:MCC = 7:3) was selected for application in formulations. The co-processed material exhibited superior compactibility compared to a physical mixture and demonstrated favorable dilution capacity in poorly compactible model drugs, including Linaoxin and Lingzhi spore powder, as well as higher biological inertness. Conclusions: These findings suggest that the co-processed PS and MCC possess excellent compactibility and dilution capacity. The co-processed excipient demonstrates applicability in direct compression manufacturing of oral solid dosage forms (e.g., tablets), offering distinct advantages for high drug-loading formulations. Full article

Developing efficient bio-based membranes is key to sustainable wastewater treatment, especially when they can be applied across multiple separation processes for components of varying molecular weights. This study reports the development and characterization of bio-based mixed matrix membranes from carboxymethyl cellulose (CMC) modified with synthesized carboxylated graphene oxide (GOCOOH), aimed at improving performance in both pervaporation and nanofiltration for water treatment. Membrane design was optimized by adjusting the GOCOOH content, applying chemical cross-linking (by immersing in glutaraldehyde with H₂SO₄), and developing highly effective supported membranes (by the deposition of a thin selective CMC-based layer onto a porous substrate). Comprehensive characterization was performed using spectroscopic, microscopic, and thermogravimetric analyses and contact angle measurements. The optimized cross-linked supported CMC/GOCOOH (5%) membrane demonstrated significantly improved transport properties: a 2.5-fold increased permeation flux and over 99.9 wt.% water in permeate in pervaporation dehydration of isopropanol, and high rejection rates—above 98.5% for anionic dyes and over 99.8% for heavy metal ions in nanofiltration. These findings demonstrate that CMC/GOCOOH membranes are promising, sustainable materials suitable for multiple separation processes involving components of varying molecular weights, contributing to more efficient and eco-friendly wastewater treatment solutions. Full article

The extraction of DNA from biological samples precedes many research and commercial applications. This study compares surface treatments of cellulose (a low-cost binding matrix) to enhance binding and elution of DNA to paper-based dipsticks. Cellulose paper was modified with poly-L-lysine, silica, or guanidine, as well as subjected to TEMPO-based oxidation. Subsequently, binding and elution behaviour of fragmented salmon sperm DNA to dipsticks was evaluated. Qubit fluorimetry and agarose gel electrophoresis measurements indicated that TEMPO-based oxidation significantly increased the binding of DNA and its elution from dipsticks, while silica modifications bound DNA efficiently, but strongly retained it. Leaching of select modifiers (guanidine, silica and poly-L-lysine) was indicated by UV/Vis spectroscopy, indicating that further optimization of attachment processes is required. This study is the first to compare multiple cellulose surface treatments for their influence on DNA binding and elution, especially the use of TEMPO-based oxidation for this purpose, and highlights some means of identifying leaching of modifiers during DNA capture at these surfaces and subsequent elution. While TEMPO-based oxidation proves a promising treatment to enhance DNA elution, further refinement of the approach is needed to ensure compatibility with molecular biology techniques. Full article

Thermoplastic chitosan/microcrystalline cellulose (TPC/MCC) composite films were prepared by thermo-compression and are reported here for the first time. L-lactic acid (LLA) was used as a plasticizer in the formation of TPC. TPC films with varying LLA contents and the TPC/MCC composite films with different MCC contents were produced for evaluation. The physicochemical, mechanical, and antibacterial properties of the thermo-compressed TPC and TPC/MCC films were characterized. LLA enhanced thermal stability and crystallinity, improved film flexibility, and reduced the water solubility of the chitosan matrix. Incorporation of MCC further improved mechanical properties and decreased water dissolution. Tensile testing showed that the addition of 5 wt% MCC increased maximum tensile strength by 82% and Young’s modulus by 124%. All TPC and TPC/MCC films exhibited antibacterial activities against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. Antibacterial efficacy decreased as MCC content increased to 20 wt%. These thermo-compressed TPC/MCC films can be tailored to display a range of properties by adjusting the contents of LLA and MCC, making them well suited for antibacterial food-packaging applications. Full article

In this study, the preparation and detailed characterization of a chitosan (CHT) impregnation system modified with cellulose nanofibrils (CNFs) and enriched with bioactive compounds—caffeine (CAF) and gallic acid (GA)—applied to the surface of unbleached paperboard were described. Their mechanical properties (tensile strength, elongation at break, and bursting strength), structural features, and surface barrier parameters (water absorption) were evaluated. The antibacterial activity of the formulations comprising 1% chitosan (1% CHT), 1% chitosan with 1% caffeine (1% CHT/1% CAF), and 1% chitosan with 1% gallic acid (1% CHT/1% GA)—applied to enhance the functionality of the coated paperboard—was additionally assessed. The incorporation of cellulose nanofibrils into the coating matrix markedly improved the mechanical performance of the paperboard, particularly in terms of puncture resistance and elongation at break, while all modified coatings retained high burst strength. Impregnations containing gallic acid or caffeine showed similar mechanical characteristics but improved flexibility without compromising structural integrity. Chitosan solutions containing gallic acid and solutions containing caffeine exhibited activity against the tested Gram-positive (S. aureus, L. monocytogenes) and Gram-negative (E. coli, P. aeruginosa) bacterial strains. Antibacterial analysis showed moderate activity against Gram-positive strains and strong inhibition of Gram-negative bacteria, with the 1% CHT/1% GA impregnation giving the largest zone of growth inhibition around the sample—19 mm in the agar diffusion test—indicating the strongest suppression of E. coli. It was found that incorporation of nanocellulose into the chitosan matrix significantly reduces water uptake by treated paperboard surface, which is critical in the context of food packaging. The best result—Cobb₆₀ value of 32.85 g/m²—was achieved for the 1% CHT/1% CNF formulation, corresponding to an 87% reduction in water absorption compared to the uncoated control. The results obtained in this study indicate a promising potential for the use of these impregnation systems in sustainable packaging applications. Full article

Cellulose aerogel is a promising thermal insulation material with terrific thermal insulation and environmental friendliness. However, the intrinsic flammability of polysaccharide molecules and dependence on freeze-drying have limited its application in flame-retardant and thermal management systems. Here, we develop a flame-retardant biomass aerogel based on a dual-network matrix of bacterial cellulose and sodium alginate. This innovative material enables high-efficiency and low-cost preparation via ambient pressure drying technology (only ~3.5% volume shrinkage), while achieving flame retardancy by introducing an inorganic nanosheet microstructure within a polymer matrix. The resulting dual-network flame-retardant cellulose aerogel demonstrates thermal performance superior to that of most polymer foams and conventional cellulose aerogels, featuring an ultra-low thermal conductivity of ~0.04 W m⁻¹ K⁻¹ and a high limiting oxygen index (LOI) of ~69%. This research provides a novel strategy for simultaneous flame-retardant modification and energy-efficient manufacturing of biomass-derived aerogels. Full article

This work deals with the preparation of a novel set of ternary polymer composites, where the matrix is a cellulose ether and the reinforcement agent is a 50:50 mixture of TiO₂ nanoparticles with PbCl₂ micropowder (0.25–4 wt%). The attained film samples are investigated from morphological, optical, and electrical points of view to explore the applicative potential as LED encapsulants or flexible dielectric layers for capacitors. Morphological analyses at micro- and nanoscale evidence the level of distribution of the fillers blended within the matrix. UV-VIS spectroscopy and refractometry emphasize that at 0.5 wt% the samples display the best balance between transparency and high refractive index, which matches the applicative criteria for LED encapsulation. The electrical testing with broadband dielectric spectrometer proves that the dielectric constant at 1 kHz of the composite with 4 wt% fillers is enhanced by about 6.63 times in comparison to the neat polymer. This is beneficial for designing eco-friendly and flexible dielectrics for capacitor devices. Full article

The growing threat of antimicrobial resistance drives the need for innovative and multifunctional therapeutic systems. In this study, a controlled-release system based on a bioactive film composed of gelatin, bacterial cellulose (BC), sericin, citric acid, PEG 400, and nisin was developed for topical applications in infected wound treatment. BC membranes were produced using Komagataeibacter xylinus and enzymatically treated to optimize dispersion within the polymer matrix. The resulting system exhibited a semi-rigid, homogeneous morphology with appropriate visual characteristics for dermatological use. Microbiological assays demonstrated significant antimicrobial activity against Gram-positive (Staphylococcus aureus) and resistant Gram-negative strains (Escherichia coli and Enterobacter cloacae), attributed to the synergistic action of nisin and citric acid, which enhanced bacterial outer membrane permeability. The antioxidant capacity was confirmed through DPPH radical scavenging assays, indicating a progressive release of bioactive compounds over time. Scanning electron microscopy (SEM) analyses revealed good integration of biopolymers within the matrix. These results suggest that the strategic combination of natural biopolymers and antimicrobial agents produced a functional system with improved mechanical properties, a broadened antimicrobial spectrum, and promising potential as a bioactive wound dressing for the treatment of infected skin lesions. Full article

Significant efforts have been dedicated to developing controlled-release systems for the effective management of colorectal cancer. In this study, a once-daily, delayed-release regorafenib (REG) tablet was fabricated using 3D printing technology for the treatment of colorectal cancer. For this, a hydrogel containing 80 mg of the drug in a matrix of hyaluronic acid, carboxymethyl cellulose, Pluronic F127, and glycerol was prepared to incorporate into the shell cavity of tablet via a pressure-assisted microsyringe (PAM). The shell was printed from an optimized ink formulation of Soluplus^®, Eudragit^® RS-100, corn starch 1500, propylene glycol 4000, and talc through melt extrusion-based 3D printing. In vitro release assays showed a drug release rate of 91.1% in the phosphate buffer medium at 8 h and only 8.5% in the acidic medium. Drug release kinetics followed a first-order model. The results showed smooth and uniform layers based on scanning electron microscopy (SEM) and drug stability at 135 °C upon TGA. FTIR analysis confirmed the absence of undesired covalent interactions between the materials. Weight variation and assay results complied with USP standards. Mechanical strength testing revealed a Young’s modulus of 5.18 MPa for the tablets. Overall, these findings demonstrate that 3D printing technology enables the precise fabrication of delayed-release REG tablets, offering controlled-release kinetics and accurate dosing tailored for patients in intensive care units. Full article

Cu-BTC (HKUST-1) metal–organic framework (MOF) is widely recognized for its carbon capture capability due to its unsaturated copper sites, high surface area, and well-defined porous structure. This study developed mixed matrix membranes (MMMs) using cellulose triacetate (CTA), incorporating bimetallic Ni-Cu-BTC MOFs for CO₂/CH₄ separation, and benchmarked them against membranes fabricated with monometallic Cu-BTC. CTA was selected for its biodegradability, membrane-forming properties, and cost-effectiveness. The optimized membrane with 10 wt.% Ni-Cu-BTC achieved a CO₂ permeability of 22.9 Barrer at 25 °C and 5 bar—more than twice that of pristine CTA—with a CO₂/CH₄ selectivity of 33.8. This improvement stems from a 51.66% increase in fractional free volume, a 49.30% rise in the solubility coefficient, and a 51.94% boost in the diffusivity coefficient. Dual-sorption model analysis further confirmed enhanced solubility and adsorption mechanisms. These findings establish CTA/Ni-Cu-BTC membranes as promising candidates for high-performance CO₂ separation in natural gas purification and related industrial processes. Full article

Bacterial nanocellulose (BNC) has gained considerable interest over the last decade due to its unique properties and versatile applications. However, the low yield and the high production cost significantly limit its industrial scalability. The proposed study explores the isolation of new BNC producers from date palm sap and the use of date waste extract as a sustainable carbon source to improve BNC productivity. Results revealed three potential BNC producers identified as Komagataeibacter sp. IS20, Komagataeibacter sp. IS21, and Komagataeibacter sp. IS22 with production yield of 1.7 g/L, 0.8 g/L and 1.8 g/L, respectively, in Hestrin-Schramm (HS) medium. The biopolymer characterization indicated the presence of type I cellulose, a high thermal stability, and a highly dense network made of cellulose nanofibrils for all BNC samples. The isolate IS22, showing the highest productivity, was selected for an optimization procedure using a full factorial design with date waste extract as a carbon source. The BNC yield increased to 6.59 g/L using 4% date waste extract and 2% ethanol after 10 days of incubation compared to the standard media (1.8 g/L). Two probiotic strains, including Bacillus subtilis (BS), and Lactobacillus plantarum (LP) were successfully encapsulated into BNC matrix through a co-culture approach. The BNC-LP and BNC-BS composites showed antibacterial activity against Pseudomonas aeruginosa. BNC–probiotic composites have emerged as a promising strategy for the effective delivery of viable probiotics in a wide range of applications. Overall, this study supports the use of date waste extract as a sustainable carbon source to enhance BNC productivity and reduce the environmental footprint using a high-yielding producer (IS22). Furthermore, the produced BNC demonstrated promising potential as an efficient carrier matrix for probiotic delivery. Full article

Carboxymethyl cellulose (CMC) films, derived from sugarcane bagasse agricultural waste (SCB) incorporated with Betalains-nitrogen-doped carbon dots (Betalains-N–CQDs), derived from beet root waste (BR), offer a sustainable, smart and naked-eye sensor for strawberry packaging due to their excellent fluorescent and shape memory properties. These CMC-Betalains-N–CQDs aim to enhance strawberry preservation and safety by enabling visual detection of common food contaminants such as bacteria, fungi and Pb(II). Crucially, the CMC-Betalains-N–CQD film also exhibits excellent shape memory properties, capable of fixing various shapes under alkaline conditions and recovering its original form in acidic environments, thereby offering enhanced physical protection for delicate produce like strawberries. Optical studies reveal the Betalains-N–CQDs’ pH-responsive fluorescence, with distinct emission patterns observed across various pH levels, highlighting their potential for sensing applications. Scanning Electron Microscopy (SEM) confirms the successful incorporation of Betalains-N–CQDs into the CMC matrix, revealing larger pores in the composite film that facilitate better interaction with analytes such as bacteria. Crucially, the CMC-Betalains-N–CQD film demonstrates significant antibacterial activity against common foodborne pathogens like Escherichia coli, Staphylococcus aureus, and Candida albicans, as evidenced by inhibition zones and supported by molecular docking simulations showing strong binding interactions with bacterial proteins. Furthermore, the film functions as a fluorescent sensor, exhibiting distinct color changes upon contact with different microorganisms and Pb(II) heavy metals, enabling rapid, naked-eye detection. The film also acts as a pH sensor, displaying color shifts (brown in alkaline, yellow in acidic) due to the betalains, useful for monitoring food spoilage. This research presents a promising, sustainable, and multifunctional intelligent packaging solution for enhanced food safety and extended shelf life. Full article

Developing advanced nuclear fuel technologies is critical for high-performance applications such as nuclear thermal propulsion (NTP). This study explores the feasibility of direct ink writing (DIW) for fabricating ceramic pellets for potential nuclear applications. Zirconium carbide (ZrC) is used as a matrix material and vanadium carbide (VC) is used as a surrogate for uranium carbide (UC) in this study. A series of ink formulations were developed with varying concentrations of VC and nanocrystalline cellulose (NCC) to optimize the rheological properties for DIW processing. Post-sintering analysis revealed that conventionally sintered samples at 1750 °C exhibited high porosity (>60%), significantly reducing the compressive strength compared to dense ZrC ceramics. However, increasing VC content improved densification and mechanical properties, albeit at the cost of increased shrinkage and ink flow challenges. Spark plasma sintering (SPS) achieved near-theoretical density (~97%) but introduced geometric distortions and microcracking. Despite these challenges, this study demonstrates that DIW offers a viable route for fabricating ZrC-based ceramic structures, provided that sintering strategies and ink rheology are further optimized. These findings establish a baseline for DIW of ZrC-based materials and offer valuable insights into the porosity control, mechanical stability, and processing limitations of DIW for future nuclear fuel applications. Full article