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We report a facile fractionation strategy using choline hydroxide (ChOH) based alkaline deep eutectic solvents (DES) for whole-component upgrading of bagasse. Through selective lignin and xylan dissolution, along with extensive biomass swelling, high-value lignin-carbohydrate complexes (LCC, with high β-O-4 bond content of 68.9/100 Ar) and high-purity xylan were extracted without compromising cellulose recovery and hydrolysis. This work provided the key to solving the technical contradiction between cellulose availability and lignin structural integrity. [ABSTRACT FROM AUTHOR]

Composites used as particleboard have recently been developed using waste-paper fibers mixed with natural rubber compound at a weight ratio of 70/30 %. The effects of silica and aluminum hydroxide fillers were studied at 0, 15, 30, 45, and 60 phr. The results showed that the hardness of the waste-paper particleboard increased with the filler content. Both types of fillers led to a slight increase in the density of the composites. Moreover, the fillers reduced the hygroscopicity and swelling of the particleboard. The use of silica resulted in lower hygroscopicity, providing greater flexural resistance and elastic modulus compared to using aluminum hydroxide. Additionally, the minimum limiting oxygen index (LOI) required to ignite the sample was slightly higher with the addition of both fillers, with silica exhibiting a higher value than filled aluminum hydroxide. Furthermore, the thermal decomposition of the specimens from the TGA test was reduced as both fillers were added, especially at temperatures above 350°C. [ABSTRACT FROM AUTHOR]

With the global attention on plastic pollution, polylactic acid (PLA) is quickly becoming an alternative to traditional plastics. The current pressing challenge now is to enhance the degradation rate of PLA while simultaneously reducing costs. We investigated the influence of reed fibers on the biodegradation of PLA-based composites under various environmental conditions. The crystallization behavior, surface morphology, and functional group changes of the samples during enzymatic degradation were analyzed using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared spectrometer (FTIR). The results indicate that reed fibers significantly increased the hydrophilicity of the composites and reduced the crystallinity of PLA, thereby enhancing the degradation rate of the composites. This rate increased with the higher concentration of reed fibers. The research results will provide a theoretical reference for the design of PLA composites that are better aligned with market demand, which is used to balance the requirements for degradation performance during product use and after disposal and expand the application of PLA/RF composites in the construction, agriculture, and packaging. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) have attracted considerable interest due to their optical properties, though their nonlinear optical behavior remains largely unexplored. In this paper, we investigate the second-order nonlinear optical (SONLO) response of CNCs through both experimental and theoretical investigations. Hyper-Rayleigh scattering (HRS) experiments revealed values comparable to well-known nonlinear optical biomaterials, such as collagen, and on par with inorganic reference materials like KDP. The strong response in CNCs can be attributed to the well-ordered structure of the cellulose chains, which enhances the overall susceptibility of the nanoparticles. Quantum chemical modeling using density functional theory (DFT) was employed to simulate the molecular hyperpolarizability of CNCs. The study reduced the complex first hyperpolarizability tensor of the CNCs to two key components, βzzz and βzyy. An electrostatic model was applied to account for the CNCs' shape and dielectric properties, leading to strong agreement with the experimental data. Our findings highlight the potential of CNCs for optoelectronic applications and provide valuable insights for characterizing CNC-based mesomaterials through two-photon microscopy. [ABSTRACT FROM AUTHOR]

Transparent wood with high transmittance and versatility has attracted great attention as an energy-saving building material. Many studies have focused on luminescent transparent wood, while the research on organic afterglow transparent wood is an interesting combination. Here, we use luminescent difluoroboron β-diketonate (BF2bdk) compounds, methyl methacrylate (MMA), delignified wood, and initiators to prepare room-temperature phosphorescent transparent wood by thermal initiation polymerization. The resultant PMMA has been found to interact with BF2bdk via dipole-dipole interactions and consequently enhance the intersystem crossing of BF2bdk excited states. The transparent wood matrix can provide a rigid environment for BF2bdk triplets and serve as oxygen barrier to suppress non-radiative decay and oxygen quenching. The prepared afterglow material has the characteristics of diverse composition, long afterglow emission lifetimes, and high photoluminescence quantum yield. This afterglow transparent wood also demonstrates potential application value in areas such as high mechanical strength, good hydrophobicity, and high cost-effectiveness. Transparent wood has potential in building applications, and there is interest in this having additional functionality. Here, the authors report the development of transparent wood with room temperature phosphorescence. [ABSTRACT FROM AUTHOR]

Environmental pollution, stemming from the disposal of contaminants, poses severe threats to ecosystems and human health. The emergence of a new class of pollutants, termed emerging contaminants (ECs), in soil, water, and air has raised global concerns, aligning with the UN 2030 Agenda's Sustainable Development Goals. Aerogels, three-dimensional structures with high porosity and low density, offer promise in addressing this issue. Cellulose-based aerogels, derived from abundant, renewable, and biodegradable sources, particularly stand out for their potential in adsorption applications. However, challenges arise in water and wastewater treatment due to cellulose aerogel's inherent hydrophilicity. To overcome this limitation, incorporating new components and employing modification processes becomes essential. This article explores the production phases and diverse modifications of cellulose aerogels, aiming to enhance their adsorption capabilities for various environmental contaminants. By addressing hydrophilicity issues and developing stable composites, cellulose aerogels can contribute significantly to efficient and sustainable solutions in the quest for cleaner ecosystems and improved human health. [ABSTRACT FROM AUTHOR]

Probiotics are an essential dietary supplement for intestinal flora balance, inhibition of pathogenic bacteria and immune regulation. However, probiotic inactivation during gastrointestinal transportation remains a big challenge for oral administration. Hence, oral delivery systems (ODSs) based on polysaccharides have been constructed to protect probiotics from harsh environments. Cellulose, chitosan, alginate and their derivates have been used to form a protective layer for probiotics. This review summarizes the superiority and application of polysaccharides in forming protective layers for probiotics. Meanwhile, ODS processes including extrusion, emulsion and spray drying are also summarized. The preparation technique mechanism, the microparticle formation process and especially the role polysaccharides serve in the preparation process are overviewed. Lastly, the need for cell viability retention during the dehydration and construction of core-shell ODS microparticles is emphasized in this review. [ABSTRACT FROM AUTHOR]

Almond shells (ASs) are a potential source of cellulose that could be obtained through sustainable methods for their valorisation. Biocomposites (BCs) from polyvinyl alcohol (PVA) and cellulose are interesting materials for developing sustainable packaging materials. BC based on PVA and AS cellulose were obtained by melt blending and compression moulding, by using subcritical water extraction at 160 or 180 °C, and subsequent bleaching with sodium chlorite (C) or hydrogen peroxide (P) to purify cellulose. The influence of the purification method on the properties of BC was analysed. Fibres treated with C were better dispersed in composites than those bleached with P. Residual phenolic compounds in the fibres provide the composite with ABTS∙+ scavenging capacity in line with the residual lignin content of the fibres. Both the presence of phenols and dispersed fibres reduced the film transparency, mainly in the UV range. Fibres enhanced the oxygen barrier capacity of composites, and those treated with HP also improved the water vapour barrier capacity. Fibres treated with C better promoted the increase in the elastic modulus of the composites, due to their highest crystallinity and dispersibility, while favoured the PVA crystallisation. Therefore, the obtained AS cellulose fibres could be used to obtain thermoprocessed PVA biocomposites for food packaging applications. [ABSTRACT FROM AUTHOR]

Food commodities, including mycotoxins naturally produced from toxigenic fungi (pre- or post-harvest), are particularly vulnerable to contamination. The study intended to use unique bioactive composites loaded with antimicrobial constituents for food packaging. Three composite types are based on carboxymethyl cellulose/shellac (CMC/SH) and loaded with pomegranate extract (POE) with or without jojoba oil (JOE) at various concentrations. An enhancement was recorded for tensile strength and elongation at break and burst properties of the composites, where the results point out the amelioration of flexibility and elasticity with E9 (0.3/3 mg/mL of POE/JO). Moreover, E10 (0.3/1 of POE/JOE) content had higher phenolic and flavonoids, with significant antioxidants and the best antimicrobial and anti-mycotoxigenic activity. Six higher antimicrobial composites were chosen for corn seed coating applications in a simulated experiment of toxigenic fungal contamination, where the results recommend E10 as the best formula for packaging application. The E10 was characterized for emulsion stability, particle size, zeta potential, pH, PDI, and acidity that were recorded at 88.16 ± 2.87%, 54.81 nm, 38.74 mV, 6.34 ± 0.54, 31.12 ± 1.02, and 6.02 ± 0.34 mg/L, respectively. The in-silico study revealed that ellagic acid and hesperidin in POE extract, erucic and oleic acids in JOE, and shellac had the highest binding free energies against the vital enzymes involved in bactericidal/bacteriostatic effects and the aflatoxin bio synthetic mechanism. [ABSTRACT FROM AUTHOR]

Cellulose fibers are an abundant material that is well known for its biodegradability. Various forms of cellulose, such as cotton, paper pulp fibers, and microcrystalline cellulose can be regarded as benchmarks for biodegradability, when comparing other materials. However, as revealed by the literature, broad ranges of time and extent of biodegradation have been reported for cellulose. These large ranges can be attributed not only to environmental factors but also to the presence of lignin, the degree and perfection of crystallinity, the size and density of the physical specimens, and chemical modifications to the cellulose, if any. Studies also have shown differences in biodegradability associated with the selection of test methods. Although cellulose is subject to well-known enzyme-promoted mechanisms of biodegradation, the evolution of plant materials has favored development of some resistance to decay, i.e. recalcitrance. Cellulosic materials are clearly less biodegradable than starch. However, they are more biodegradable than various synthetic or bio-based plastics, as well as some cellulose derivatives, which persist in ocean water or soils for very long periods. This review indicates that cellulose biodegradability, while generally rapid and natural, has a rate and extent that depends on a complex and sometimes subtle set of environmental and chemical factors. [ABSTRACT FROM AUTHOR]

This study investigates the sustainable use of Eucalyptus spp. bark through different chemical (hydrothermal, acid, alkaline, and bleaching) and physical (milling) pretreatments in the production of sustainable films. Valorization of agro-industrial residues and the demand for sustainable materials pose challenges for environmentally responsible solutions. Eucalyptus spp. bark, rich in cellulose, hemicellulose, and lignin, is a promising source for creating sustainable materials like films. In this study, the use of chemical and physical treatments aims to optimize biomass extraction and improve the chemical, thermal, mechanical, and optical properties of the films. The films showed an excellent light barrier capacity, with a transmittance below 1%. Crystallinity indices varied with the pretreatment: 8.15% for hydrothermal, 7.01% for alkaline, 7.63% for acid, and 10.80% for bleaching. The highest crystallinity value was obtained through bleaching, by removing amorphous components like lignin and hemicellulose. The alkaline pretreatment yielded stronger films (maximum stress of 8.8 MPa, Young's modulus of 331.3 MPa) owing to the retained lignin and the hemicellulose reinforcing the material. This study contributes to the field of sustainable development by converting residues into valuable materials and by advancing the circular economy. The films' specific properties make them suitable for applications like sustainable packaging, addressing environmental and industrial challenges. [ABSTRACT FROM AUTHOR]

Palm Leaf Manuscripts represent a significant component of the world's cultural heritage. Investigating their primary chemical components and understanding the transformations these materials undergo under environmental influences are crucial for elucidating their material characteristics and aging mechanisms and developing effective strategies for preventive conservation. This study utilized infrared absorption spectroscopy and X-ray diffraction analysis to examine changes in the primary chemical components of Palm Leaf Manuscripts under varying relative humidity conditions over extended periods. The findings reveal that dry environments lead to surface cracking, while humid environments promote mold growth, both of which contribute to the degradation of the primary chemical components. These degradative processes reduce cellulose crystallinity and thermal stability. The deterioration is particularly severe under high humidity, with hemicellulose degrading faster and more extensively than cellulose under the same conditions. After 200 days of aging at 10% RH and 90% RH, cellulose degradation reached 19.82% and 54.40%, respectively, while hemicellulose degradation was 34.78% and 64.28%. Correspondingly, the relative crystallinity of cellulose decreased by 8.01% and 13.11%. In contrast, samples maintained at 50% RH exhibited minimal deterioration, with cellulose and hemicellulose degrading by only 4.08% and 13.55%, respectively, and a 6.61% reduction in cellulose crystallinity. These results suggest that a relative humidity of 50% is optimal for the preservation of Palm Leaf Manuscripts. This study offers significant insights into the ageing mechanisms and preventive conservation of Palm Leaf Manuscripts, as well as other cellulose-based organic heritage materials. [ABSTRACT FROM AUTHOR]

Nanocomposites based on metal nanoparticles (MNP) prepared with mangosteen (mgt) peel extract-mediated biosynthesis of Agmgt/Znmgt have attracted considerable interest due to their potential for various practical applications. In this study, their role in developing antibacterial protection for rubber cotton gloves is investigated. The process of mangosteen-peel-extract-mediated biosynthesis produced Agmgt/Znmgt nanocomposites with respective diameters of 23.84 ± 4.08 nm and 30.99 ± 5.73 nm, which were assessed in the context of antimicrobial rubber-coated gloves. The rubber glover surface exhibited a very dense deposition of the Ag+Znmgt nanocomposite, which subsequently demonstrated level 4 resistance to punctures under the ANSI-ISEA 105-2016 standard. This could be attributed to the Zn-cellulose double formation on the rubber surface. Notably, on testing the inhibition of bacterial growth, the extract with the Agmgt nanoparticles presented the least concentration capable of growth inhibition in comparison to the extracts with Znmgt and Ag+Znmgt nanoparticles. Each of the mangosteen extracts was shown to inhibit bacterial growth when tested against both Gram-positive cocci and Gram-negative bacilli, with MIC in the range 40–320 µg/mL. The growth of drug-resistant bacteria (MRSA) could also be inhibited with an MIC value of 160 µg/mL, and with 30 min of contact, gloves with respective coatings of Znmgt and Ag+Znmgt extract nanocomposites were shown to inhibit K. pneumoniae and MRSA. However, while effective bacterial inhibition occurred with the suspensions, the coatings on glove surfaces required a lengthy incubation period (contact time) of at least 30 min for efficacy. [ABSTRACT FROM AUTHOR]

The rapid growth of the textile industry has led to a sharp increase in dye-filled wastewater, posing a significant environmental concern. Adsorption is a promising method for dye removal, but traditional adsorbents often fall short due to limited capacity, lack of sustainability, and low selectivity. Nanocellulose-based materials have shown great potential, with some achieving high adsorption capacities, such as 3429.23 mg/g for Congo Red on cellulose-based aerogel and 2282.3 mg/g for malachite green on magnetic nanocellulose-based adsorbents. These adsorbents follow various adsorption models, including Langmuir and Freundlich isotherms, and kinetic models such as the pseudo-second-order model indicating strong interactions with target dyes. This review thoroughly examines nanocellulose-based adsorbents, exploring their types, properties, and preparation methods. This review analyses dye interactions, including factors influencing adsorption, and provides an in-depth look at adsorption kinetics, isotherms, and thermodynamics. Also, this review aims to clarify the true potential of nanocellulose-based adsorbents for dye removal, summarizing recent advancements while identifying research gaps and future directions to support further development in this field.Article Highlights: Nanocellulose adsorbents show strong potential for eco-friendly dye removal from wastewater Nanocellulose unique structure enhances dye adsorption via physisorption, hydrogen bonding, and electrostatic forces. Key factors influencing dye removal efficiency are explored, highlighting areas for future research [ABSTRACT FROM AUTHOR]

To address large volumetric expansion and low conductivity of bismuth-based anodes, an ion-replacement technique is proposed to prepare Bi/C composites, using 1,3,5-benzenetricarboxylicacid (H3BTC) based metal–organic framework as precursors. The characterizations reveal that the Bi/C composite derived from Cu-H3BTC is a sheet structure with the size of 150 nm, and Bi nanoparticles are uniformly dispersed in carbon sheets. When assessed as anode material for sodium ion batteries (SIBs), a sheet-like Bi/C anode exhibits superior sodium storage performance. It delivers a reversible capacity of 254.6 mAh g−1 at 1.0 A g−1 after 100 cycles, and the capacity retention is high at 91%. Even at 2.0 A g−1, the reversible capacity still reaches 242.8 mAh g−1. The efficient sodium storage performance benefits from the uniform dispersion of Bi nanoparticles in the carbon matrix, which not only provides abundant active sites but also alleviates the volume expansion. Meanwhile, porous carbon sheets can increase the electrical conductivity and accelerate the electrochemical reaction kinetics. [ABSTRACT FROM AUTHOR]