ACS Sustainable Chemistry & Engineering最新文献

The application of plant-growth-promoting rhizobacteria in open-field agriculture is challenged by the lack of adequate technologies to preserve them in anhydrous conditions and deliver them to the rhizosphere. Here, the transacetalization of chitosan with trehalose allows the synthesis of a new biopolymer, namely chito_tre, that can support the encapsulation, storage, and delivery of plant growth-promoting rhizobacteria (PGPRs) in a seed-coating format. In the liquid phase, chito_tre preserves largely used PGPRs such as Rhizobium tropici, Azorhizobium caulinodans, Bradyrhizobium japonicum, Klebsiella variicola, and Pseudomonas fluorescens, with a log reduction <1 at 48 h and at room temperature. In the solid phase, chito_tre enables the preservation of PGPRs up to 28 days, with a log reduction at room temperature circa equal to 2 (K. variicola), 4 (B. japonicum, A. caulinodans, P. fluorescens), and 5 (R. tropici), depending on the microorganism considered. When applied as a seed coating, chito_tre loaded with PGPRs facilitates root colonization in Cicer arietinum (chickpea), Glycine max (soybean), Sesbania sesban (Egyptian riverhemp), and Zea mays (corn), boosts root development, and enables a synergistic strategy to enhance plant growth. Together, these results demonstrate the functionalization of largely available biopolymers with osmoprotectants to establish a new class of seed-coating materials that can enhance plant growth.

Since the demand for sustainable and renewable fuels has increased, the use of side products and especially industrial waste byproducts has become crucial. Therefore, the application of crude glycerol from the biorefinery to Pichia pastoris (Komagataella phaffii) cultivation and recombinant Sugiyamaella lignohabitans xylanase production was investigated as one of its potential further applications. This enzyme cleaves the xylan backbone into xylooligosaccharides (XOs), which are easier to hydrolyze to xylose. High cell-density cultivation (HCDC) with pure glycerol resulted in the xylanase activity of 0.89 U/mL of extracellularly produced enzyme and the productivity of 6.28 U/L/h. The xylanase expression was positively influenced by crude glycerol impurities in all cases. The highest increase in enzyme activity and productivity was achieved when partially purified (1.50 U/mL and 7.34 U/L/h) and even when nonpurified crude glycerol (1.59 U/mL and 9.13 U/L/h) were used. These findings suggest the potential valorization of biodiesel byproduct application for more sustainable biofuel production and its application in biorefineries.

2,5-Furandicarboxylic acid (FDCA), a pivotal oxidation product derived from the biomass platform molecule 5-hydroxymethylfurfural (HMF), has garnered considerable attention for its extensive potential applications across a wide array of industries, including food packaging, electronics, automotive manufacturing, and textiles. Currently, the production of FDCA relies heavily on high-purity HMF, which facilitates excellent product yields. However, the inherent sensitivity of HMF to pH fluctuations and environmental factors such as light, heat, and oxygen posed considerable challenges, as these conditions could readily lead to its degradation. Additionally, the high costs associated with HMF production and purification further complicated the synthesis process. In light of these issues, there is growing research interest and practical value in developing processes that enable the direct synthesis of FDCA from carbohydrates without the need for intermediate purification steps. Nevertheless, the inevitable formation of humins during the reaction process posed substantial obstacles to achieving this goal. This review systematically summarizes recent advances in the direct conversion of carbohydrates, such as fructose, glucose, polysaccharides, and aldaric acids, into FDCA without requiring highly purified intermediates. The review delves into various catalytic systems, elucidating the reaction mechanisms and pathways involving key intermediates such as HMF, 2,5-diformylfuran (DFF), 5-acetoxymethylfurfural (AMF), 5-chloromethylfurfural (CMF), and 5-alkoxymethylfurfural (RMF). Additionally, this review highlights the advantages of these catalytic systems while also considering their optimization potential. Furthermore, the review incorporates sustainability assessments and technical–economic analyses of FDCA production, emphasizing the importance of evaluating both environmental impacts and economic viability. By integrating these analyses, the review aims to identify pathways that not only enhance the efficiency and cost-effectiveness of FDCA production but also align with sustainability goals. Ultimately, this review provides innovative solutions and insights designed to advance highly selective synthetic pathways and develop cost-effective purification methods for FDCA, thereby paving the way for more sustainable and efficient industrial applications. This comprehensive approach ensures that the production processes are not only economically feasible but also environmentally responsible, promoting a shift toward greener industrial practices.

Printed and flexible electronics hold the potential to revolutionize the world of electronic devices. A primary focus today is their circularity, which can be achieved by using biobased materials. In this study, electrically conductive bionanocomposite materials suitable for flexible electronics were fabricated using proteins from the black soldier fly (BSF, Hermetia illucens). The valorization of BSF biomacromolecules is currently being pursued in the framework of emerging circular economy models for the bioconversion of the Organic Fraction of Municipal Solid Waste (OFMSW), where BSF has been demonstrated to act as an extremely efficient bioconverter to provide lipids, chitin, and proteins. Here, the BSF protein extracts were characterized by proteomic techniques, revealing a pool of myofibrillar proteins able to interact through intermolecular β-sheet interactions. Flexible and electroconductive bionanocomposite materials were next formulated by combining BSF proteins with a conductive carbon black (CCB), either in its pristine form or functionalized with 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (serinol pyrrole, SP), using water as the only solvent and incorporating glycerol and carboxymethylcellulose (CMC) as additional green ingredients. A sustainable, low-pressure cold plasma (LPCP) technology was ultimately proposed to achieve high film surface hydrophobicity. Characterized by effective biodegradability, strain-sensing properties, high electrical conductivity (up to 0.9 × 10^–2 S/cm at a filler content of 8% v/v (15% w/w)), and high surface hydrophobicity, the bionanocomposites presented here may be well suited for disposable flexible electronics, as in wearable devices, electrostatic discharge fabrics, or packaging, hence offering new routes toward OFMSW valorization and the development of green flexible electronics.

Research on sustainable bionanocomposite films from insect proteins for the full valorization of the organic fraction of municipal solid waste.

Low conversion of enzymatic hydrolysis of crystalline poly(ethylene terephthalate) (PET) impacts its recycling and end-of-life persistence. Yet, the mechanistic insights into the heterogeneous enzymatic reaction process and the impact of crystallinity remain poorly understood. Here, we combined adsorption and Michaelis–Menten kinetic experiments to examine the influence of PET crystallinity and particle size on depolymerization by a commercial cutinase (HiC). Batch adsorption experiments and modeling revealed that HiC adsorption was unaffected by PET crystallinity. Conventional and inverse Michaelis–Menten kinetic experiments and modeling indicated that the low hydrolysis rates of crystalline PET were more due to slower kinetics rather than low reaction densities. Under the same crystallinity, intrinsic reactivity between different particle sizes was different for amorphous PET. Furthermore, the reaction densities of HiC exceeded adsorption densities by 3–10-fold across all PET, implying that solution phase hydrolysis of oligomers released by initially adsorbed enzyme yielded most monomer products. Finally, prephotoweathering increased initial hydrolysis rates up to an order of magnitude for amorphous PET, highlighting the potential role of UV in PET recycling and environmental persistence. Overall, quantitative insights from this work can guide the rational design of enzymes and recycling processes and inform the end-of-life fate of PET waste.

Natural biobased materials, which can be obtained from crustacean exoskeletons, angelica sinensis, vanilla beans, amino acids, etc., have significant potential as eco-friendly corrosion inhibitors. In this study, several eco-friendly materials (chitosan (CTS), ferulic acid (FA), cysteine (Cys), and methionine (Met)) were proposed as corrosion inhibitors to improve the corrosion resistance of steel. Their inhibition effects and mechanisms in simulated concrete pore (SCP) solution were evaluated by electrochemical, surface measurements, quantum chemical (QC) calculations, and molecular dynamics (MD) simulations. The results showed that these inhibitors effectively improved the corrosion resistance of steel, especially for CTS (with a maximum inhibition efficiency of 92.6%). The adsorption of these inhibitors followed Langmuir and Freundlich adsorption isotherms, revealing the physical–chemical mixed adsorption modes. Surface characterization techniques revealed that the protective layers formed by these inhibitors could effectively inhibit the corrosion of the steel. QC calculations and MD simulations further confirmed the experimental results. Performance of cement mortar measurements revealed that these four inhibitors exhibited no effect on the workability of fresh mortar and improved the strength of mortar specimens, with a maximum increase in the compressive strength of 11.18%. This study is of great significance to improving the durability of reinforced concrete in the future.

Pretreatment is critical to promote enzymatic hydrolysis for the production of lignocellulose-based biofuels. In this study, inspired by the lignin degradation through the mouthpart and symbiotic fungi of termite, a synergistic biomass pretreatment system using ball milling and Fenton-like reactions was first proposed. Ball milling can reduce the particle size, while Fenton-like reactions can modify the lignin and cause pore structures, leading to a 44.2% increment in total pore volume. In addition, lignin-based aromatic aldehydes can be produced with a 67.1% increase in yield over no-ball milling conditions, which can be used as natural mediators. More importantly, under the optimal pretreatment conditions (1.5% H₂O₂, 1 mg L^–1 Fe-TAML catalyst, 300 rpm, and 12 h), the highest initial glucose productivity was 2.83 g L^–1 h^–1, which is 2.4 times higher than untreated samples. The conversion of cellulose in 24 h is enhanced by 62.3% with half of the enzyme input when compared with untreated wheat straw. Thus, the synergy of ball milling and Fenton-like reactions helps to promote lignin depolymerization and enzymatic hydrolysis of lignocellulose.