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Excessive usage of biologically toxic fungicides and their matrix materials poses a serious threat to public health. Leveraging fungicide carriers with inherent pathogen inhibition properties is highly promising for enhancing fungicide efficacy and reducing required dosage. Herein, a series of coacervates have been crafted with lignin and surfactin, both of which are naturally derived and demonstrate substantial antifungal properties. This hierarchically assembled carrier not only effectively loads fungicides with a maximum encapsulation efficiency of 95% but also stably deposits on hydrophobic leaves for high-speed impacting droplets. Intriguingly, these coacervates exhibit broad spectrum fungicidal activity against eight ubiquitous phytopathogens and even act as a standalone biofungicide to replace fungicides. This performance can significantly reduce the fungicide usage and be further strengthened by an encapsulated fungicide. The inhibition rate reaches 87.0% when 0.30 mM pyraclostrobin (Pyr) is encapsulated within this coacervate, comparable to the effectiveness of 0.80 mM Pyr alone. Additionally, the preventive effects against tomato gray mold reached 53%, significantly surpassing those of commercial adjuvants. Thus, it demonstrates that utilizing biosurfactants and biomass with intrinsic antifungal activity to fabricate fully biobased coacervates can synergistically combine the functions of a fungicide carrier and antifungal agent against phytopathogens and guarantee environmental friendliness. This pioneering approach provides deeper insights into synergistically enhancing the effectiveness of agrochemicals from multiple aspects, including fungicide encapsulation, cooperative antifungal action, and droplet deposition.

The fermented corn stover residues are abundant renewable lignin-rich bioresources that show great potential to produce aromatic phenols. However, selective catalytic hydrogenolysis of this residual material still remains challenge to obtain high yields. Herein, a novel strategy to produce monophenolic compounds from the fermented stover over a commercial Pd/C catalyst was proposed. Taking the reaction temperature as the key variable, the highest monomer yield was 28.5 wt% at 220 °C in compaction with that of the pristine corn stover (22.8 wt%). The enhanced monophenol yield was due to the higher contents of lignin and less recalcitrance in the fermented stover. Moreover, the van Krevelen diagram revealed a slight selective CO bond scission of lignin macromolecular during fermentation as well as the dehydration and deoxygenation in hydrogenolysis reaction. Overall, this work opens a new avenue for the valorization of lignin through reductive catalytic fractionation of agricultural wastes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Lignin-carbohydrate complexes (LCCs) are emerging as a new and natural product with pharmacological and nutraceutical potential. It is uncertain, however, whether LCCs have a positive effect on the microbiota of the gut based on the current evidence. Here, the LCC extracted from beechwood (BW-LCC) was used as a substrate for in vitro fermentation. The lignin in BW-LCC consisted of guaiacyl (G) and syringyl (S) units, which are mainly linked by β-O-4 bonds. After 24 h of in vitro fermentation, the pH had evidently declined. The concentrations of acetic acid and propionic acid, the two main short-chain fatty acids (SCFAs), were significantly higher than in the control group (CK). In addition, BW-LCC altered the microbial diversity and composition of gut microbes, including a reduction in the relative abundance of Firmicutes and an increase in the relative abundance of Proteobacteria and Bacteroidetes. The relative abundance of Escherichia coli-Shigella and Bacteroides were the most variable at the genus level. The genes of carbohydrate-active enzymes (CAZymes) also changed significantly with the fermentation and were related to the changes in microbes. Notably, the auxiliary actives (AAs), especially AA1, AA2, and AA3_2, play important roles in lignin degradation and were significantly enriched and concentrated in Proteobacteria. From this study, we are able to provide new perspectives on how gut microbes utilize LCC.

Pretreatment is the initial stage of lignocellulosic biorefinery process, but is limited by the time-consuming processes, harsh conditions and/or undesirable products. Herein, a mild (<60 °C) and highly efficient pretreatment strategy is developed. The novel mechanocatalytical reaction system driven by fluid shear force helps to exfoliate cellulose from lignocellulose, and the heat generated by the shear process can be used to precipitate and recover the dissolved cellulose from the precooled NaOH/urea solution. The regenerated cellulose shows satisfying crystal structure (cellulose II), significantly decreased crystallinity and nearly tripled enzymolysis glucose yield. Almost 90% of lignin and hemicellulose could be rapidly separated. The separated lignin shows a nearly native structure with 64% β-O-4 linkage, which is even higher than the ball-milling lignin (60%). This research provides a theoretical guidance for the mild pretreatment of lignocellulosic biomass, which will push the application of mechanocatalytical reaction system in biorefinery processes on a large scale., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

As an abundant aromatic biopolymer, lignin has the potential to produce various chemicals, biofuels of interest through biorefinery activities and is expected to benefit the future circular economy. However, lignin valorization is hindered by a series of constraints such as heterogeneous polymeric nature, intrinsic recalcitrance, strong smell, dark colour, challenges in lignocelluloses fractionation and the presence of high bond dissociation enthalpies in its functional groups etc. Nowadays, industrial lignin is mostly combusted for electricity production and the recycling of inorganic compounds involved in the pulping process. Given the research and development on lignin valorization in recent years, important applications such as lignin-based hydrogels, surfactants, three-dimensional printing materials, electrodes and production of fine chemicals have been systematically reviewed. Finally, this review highlights the main constraints affecting industrial lignin valorization, possible solutions and future perspectives, in the light of its abundance and its potential applications reported in the scientific literature., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Lignin is the most abundant, renewable aromatic resource on earth and holds great potential for the production of value-added chemicals. The efficient valorization of lignin requires to deal with several formidable challenges, especially to prevent it from re-condensation reactions during its depolymerization. Recently, a strategy involving the activation of lignin side chains by selective oxidation of the benzylic alcohol in β-O-4 linkages to facilitate lignin degradation to aromatic monomers has become very popular. This strategy provides great advantages for lignin selective degradation to high yields of aromatics under mild conditions, but requires an additional pre-oxidation step. The purpose of this review is to provide the latest cutting-edge innovations of this novel approach. Various catalytic systems, including those using chemo-catalytic methods, physio-chemo catalytic methods, and/or bio-catalytic methods, for the oxidative activation of lignin side chains are summarized. By analyzing the current situation of lignin depolymerization, certain promising directions are emphasized., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The exploration of effective approaches for the valorization of lignin to valuable products attracts broad interests of a growing scientific community. By fully unlocking the potential of the world's most abundant resource of bio-aromatics, it could improve the profitability and carbon efficiency of the entire biorefinery process, thus accelerate the replacement of fossil resources with bioresources in our society. The successful realization of this goal depends on the development of technologies to overcome the following challenges, including: 1) efficient biomass pretreatment and lignin separation technologies that overcomes its diverse structure and complex chemistry challenges to obtain high purity lignin; 2) advanced chemical analysis for precise quantitative characterization of the lignin in chemical transformation processes; 3) novel approaches for conversion of biomass-derived lignin to valuable products. This review summarizes the latest cutting-edge innovations of lignin chemical valorization with the focus on the aforementioned three key aspects., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Super Lewis acids containing the triflate anion [e.g., Hf(OTf) 4 , Ln(OTf) 3 , In(OTf) 3 , Al(OTf) 3 ] and noble metal catalysts (e.g., Ru/C, Ru/Al 2 O 3 ) formed efficient catalytic systems to generate saturated hydrocarbons from lignin in high yields. In such catalytic systems, the metal triflates mediated rapid ether bond cleavage through selective bonding to etheric oxygens while the noble metal catalyzed subsequent hydrodeoxygenation (HDO) reactions. Near theoretical yields of hydrocarbons were produced from lignin model compounds by the combined catalysis of Hf(OTf) 4 and ruthenium-based catalysts. When a technical lignin derived from a pilot-scale biorefinery was used, more than 30 wt % of the hydrocarbons produced with this catalytic system were cyclohexane and alkylcyclohexanes in the jet fuel range. Super Lewis acids are postulated to strongly interact with lignin substrates by protonating hydroxyl groups and ether linkages, forming intermediate species that enhance hydrogenation catalysis by supported noble metal catalysts. Meanwhile, the hydrogenation of aromatic rings by the noble metal catalysts can promote deoxygenation reactions catalyzed by super Lewis acids., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synthesis of high-efficiency and low-cost catalysts for hydrodeoxygenation (HDO) of waste lignin to advanced biofuels is crucial for enhancing current biorefinery processes. Inexpensive transition metals, including Fe, Ni, Cu, and Zn, were severally co-loaded with Ru on HY zeolite to form bimetallic and bifunctional catalysts. These catalysts were subsequently tested for HDO conversion of softwood lignin and several lignin model compounds. Results indicated that the inexpensive earth-abundant metals could modulate the hydrogenolysis activity of Ru and decrease the yield of low-molecular-weight gaseous products. Among these catalysts, Ru-Cu/HY showed the best HDO performance, affording the highest selectivity to hydrocarbon products. The improved catalytic performance of Ru-Cu/HY was probably a result of the following three factors: (1) high total and strong acid sites, (2) good dispersion of metal species and limited segregation, and (3) high adsorption capacity for polar fractions, including hydroxyl groups and ether bonds. Moreover, all bifunctional catalysts proved to be superior over the combination catalysts of Ru/Al 2 O 3 and HY zeolite., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The extremely low utilization efficiency of pesticides has driven people to develop low‐cost, sustainable, and smart delivery systems. Pickering emulsion (PE) derived from biomass is an attractive candidate. However, the stability of PE is insufficient, and pesticide release from PE can be hardly tuned. Herein, a facile in situ PE modification strategy to construct a stable and high‐performance pesticide delivery system from biomass resources is reported. In this process, PE stabilized by alkali lignin nanoparticles is initially prepared, and subsequently, opposite‐charged chitosan (CH), and sodium lignosulfonate (SL) are alternatively deposited onto the PE interface through layer‐by‐layer assembly to form a microcapsule system (CH+SL)n@PE. The resulting biomass‐based microcapsules show improved stability, high encapsulation efficiency, and super UV protection to avermectin (AVM), a hydrophobic and photo‐sensitive pesticide. Furthermore, the shell thickness of microcapsules can be finely tuned by controlling the deposited CH+SL layers, which enable (CH+SL)n@PE to have adjustable release behaviors. (CH+SL)20@PE prolongs the half‐life of AVM under UV irradiation by 5.0‐fold. Moreover, (CH+SL)n@PE exhibits pH and laccase dual responsiveness, which is beneficial to the targeted release of AVM in vivo. Therefore, the current PE modification strategy can provide an eco‐friendly, low‐cost, and smart system for precise delivery of pesticides. [ABSTRACT FROM AUTHOR]

Lignin, an underutilized component of lignocellulosic biomass, is regarded as a rich reservoir for the production of aromatic chemicals and fuels. Despite extensive research in recent years, lignin's potential is far from being fully unlocked. Photocatalysis that uses sustainable solar energy to drive lignin conversion under mild conditions has been identified as a promising strategy and received growing research interest. This review aims to present a critical introduction to the photocatalytic conversion of lignin, including a summary of lignin conversion pathways and mechanisms, as well as the latest cutting‐edge innovations on photocatalyst design and reactor construction. Moreover, the screening of solvents and regulation of other key factors that are involved in photocatalytic lignin conversion are also elucidated and future perspectives and challenges for photocatalytic conversion of lignin into valuable products are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Hydrodeoxygenation of biorefinery lignin‐rich wastes to jet fuel hydrocarbons offers a significant opportunity for enhancing the overall operational efficiency, carbon conversion efficiency, economic viability, and sustainability of biofuels production. However, these wastes usually mainly contain lignin with sugars, furans, and their derivatives as “impurities”. Although several factors, including reactant structure, solvents, or the decreased ratio of catalyst to reactant, could be responsible for the jet fuel hydrocarbons yield loss, we found evidence that glucose, xylose, and 5‐hydroxymethylfurfural dramatically decreased conversion yields. For example, xylose and glucose lowered the final hydrocarbon yield by 78 and 63 %, respectively. The results revealed that these compounds could suppress metal catalysts and inhibit lignin depolymerization and hydrodeoxygenation (HDO) reactions thus decrease yields of jet fuel range hydrocarbons from biomass‐derived lignin. The first‐principles calculations and TGA results from spent catalysts validated these findings. [ABSTRACT FROM AUTHOR]

The catalytic conversion of lignocellulosic biomass to aviation fuel is identified as a key strategy to alleviate high operating costs and serious environmental pollution caused by using petroleum-derived fuels. Aviation fuel with stringent end-use requirements consists of several specific hydrocarbon compositions, and the conversion of lignocellulose to aviation fuel is more challenging than that to other fuels. In this study, the latest cutting-edge innovations on the catalytic conversion of lignocellulose to aviation fuel was summarized. Promising routes for the catalytic conversion of cellulose, hemicellulose, lignin, and their derivatives were elaborated, with emphasis on those catalytic approaches including depolymerization of C–O bonds, formation/rearrangement of C–C bonds, and hydrodeoxygenation (HDO) removal of oxygen-containing functional groups. Innovations on reaction mechanism exploration, catalyst development, solvent screening, and reaction condition optimization were introduced. It revealed that a 100% biomass-derived aviation fuel could be produced by catalytic methods with the full utilization of all lignocellulosic compositions. Straight and branched paraffins in aviation-fuel range could be generated from cellulose and hemicellulose via various intermediates including 5-hydroxymethylfurfural (HMF), furfural, levulinic acid, and γ−valerolactone. The degradation and HDO conversion of lignin could yield aromatics and cycloparaffins in aviation range. The development of hydrothermal stable catalysts for the controllable formation of C–C bonds among platform chemicals from carbohydrates as well as for the efficient HDO conversion of fuel precursors is particularly important. Image 1 • All compositions in lignocellulose can be catalytically converted to aviation fuel. • A 100% biomass-derived aviation fuel can be produced by catalytic methods. • Paraffins for aviation fuel can be produced from cellulose and hemicellulose. • Cycloalkanes and aromatics for aviation fuel can be generated from lignin. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) reactions are extensively employed in the conversion of biomass to advanced fuels, which rely heavily on bifunctional catalysts that contain both a metal component and an acidic component. A significant challenge in the development of HDO catalysts is the need to reduce costs while simultaneously enhancing catalytic efficiency. Here, a series of Ru@W/ZrO 2 catalysts with an extremely low loading of Ru (0.5 wt%) were successfully synthesized using different Ru or W loading sequences and different Ru/W mass ratios. The catalysts were applied in the HDO reaction of lignin-derived phenols, and their physical and chemical characteristics were revealed by various characterization techniques, including XRD, H 2 -TPD, NH 3 -TPD, and XPS. The results suggest that the synthesis method with post-loading Ru leads to improved exposure and utilization of the low-loaded Ru, which effectively serves as the active sites for hydrogenation in catalytic reactions. Under the same reaction conditions, the bifunctional catalyst with post-loading of Ru achieved a complete conversion of phenol into cyclohexane, while the catalyst with simultaneous loading of Ru and W only yielded 42% of cyclohexane. In addition, the Ru/W ratios have also shown significant effects on the HDO performance of the catalyst. The catalyst exhibits the highest hydrogenation activity when the Ru/W ratio is 10, which is further supported by kinetic experiments. This study highlights the significance of the loading sequence of noble metals and the metal/acid ratio in the synthesis of highly active bifunctional catalysts, and also lays the groundwork for the efficient utilization of noble metals in biomass HDO conversion. • Bifunctional catalyst with extremely low loading of Ru was synthesized for bio-jet fuel production. • The post loading of Ru maximized the noble metal utilization, leading to superior catalytic performance. • The Ru/W ratios significantly affect the hydrodeoxygenation performance of the catalyst. • Lignin derived phenols were efficiently converted into cycloalkanes by the developed catalyst. [ABSTRACT FROM AUTHOR]

In pursuit of low-carbon development, the production of diverse functional materials from renewable resources, especially lignocellulosic biomass, is of vital importance. Lignin is a major component of lignocellulose, and it is nature's only true high-volume aromatic polymer, which has the advantages of biodegradability, biocompatibility, and low acquisition cost. After modification by a variety of physicochemical strategies, it can be applied as an alternative to basic industrial materials, including polyurethanes, phenolic, and epoxy resins, which stands comparably to conventional synthetic polymers in terms of both performance and reduced cost. To further unlock the potential of lignin, an alluring opportunity is the exploitation of lignin for high-value materials, especially nanomaterials, that find extensive applications in energy and environment areas. This review provides a systematic summary and perspective of research that has been devoted to lignin transformation to high-value materials, ranging from industrially well-established engineering materials to the recently emerged nanomaterials that were used for energy and environment applications. Latest cutting-edge innovations on lignin modification, controlled depolymerization, and assembly during the last five years are summarized. Structure-function relationships of lignin materials in terms of their specific applications are analyzed. Furthermore, challenges and future opportunities for lignin conversion to high-value materials are also provided. We wish this review will stimulate further advances in lignin based high-value materials, and promote "waste" into "wealth". • Lignin-based materials are the way of high-value utilization of biomass. • The development of lignin chemistry is reviewed in this paper. • The modification methods of lignin are summarized. • The application of lignin-based polymer materials is evaluated. • Lignin-based nanomaterials and lithium battery materials are summarized. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd NPs are highly dispersed on defective Al-metal organic framework via a facile method. • Missing linker defects produce coordinatively unsaturated metal sites (CUMSs) as catalytic sites. • Defects enhance the catalyst acidity and improve catalytic activity. • Defect engineering of MOFs opens up novel opportunities for lignin valorization. • DFT calculations revealed that the HDO of vanillin underwent a cascade of hydrogenation-hydrogenolysis routes. Designing highly active catalysts for selective hydrodeoxygenation (HDO) of lignin-derived oxygenates into well-defined compounds is of great importance for realizing high-value utilization of lignin. Defect engineering in metal–organic frameworks (MOFs) is an emerging concept for tailoring MOF properties, which might be a promising strategy in the synthesis of high-performance catalysts. Herein, we developed a facile synthetic strategy by adding trifluoroacetic acid as the modulator to prepare a bifunctional catalyst (Pd/NH 2 -MIL-53-d) consisting of Pd nanoparticles highly dispersed on defective NH 2 -MIL-53(Al). Characterizations, including TEM, XRD, IR, XPS and NH 3 -TPD, were employed to reveal the morphology and physicochemical properties of the catalysts. Results indicated that the introduction of defects leads to the generation of coordinatively unsaturated metal sites, which can act as anchor points for high-dispersion of Pd nanoparticles and as additional active acid sites for catalytic reactions. 100% conversion of vanillin and other 8 representative derivates of lignin into their decarbonyl products with yields over 99% has been achieved under mild conditions in the water. Density functional theory calculations revealed that the HDO of vanillin into 2-methoxy-4-methylphenol mainly underwent a cascade of hydrogenation-hydrogenolysis routes, and the synergistic interaction between Pd and defective NH 2 -MIL-53(Al) facilitated the novel bifunctional catalyst to exhibit outstanding catalytic performance. No apparent deactivation of the catalyst was noticed after it was reused 5 times. Therefore, engineering of defects in MOFs holds enormous potential in designing novel bifunctional catalysts for lignin valorization. [ABSTRACT FROM AUTHOR]

Lignin is a versatile bioaromatic polymer, with great potentials in the preparation of advanced materials due to its anti-UV and anti-oxidant properties. However, the high heterogeneity of lignin seriously hinders its practical applications. In this study, alkali lignin with limited content of hydroxyl groups and a wide distribution of molecular weight was modified by selective phenolation, which not only resulted in a dramatical increase in the content of phenolic hydroxyl groups but also led to a more uniform structure of lignin. Catechol, as compared with phenol and pyrogallol, was the most suitable phenolation reagent to reacted with lignin, and the phenolic hydroxyl content of the catechol modified lignin increased by 318.89%. Besides, the molecular weight and polydispersity index of lignin after the modification decreased, which led to a small and regular size of lignin particles prepared by acid precipitation. Subseqently, lignin particles were used to prepare Pickering emulsions for avermectin (AVM) encapsulation, and the stability as well as the anti-UV and anti-oxidant capacities of Pickering emulsions prepared by using phenolated lignins as solid surfactants were obviously enhanced. The encapsulation efficiency of AVM in Pickering emulsions was also improved, which could reach high above 90%. Moreover, AVM protected by lignin-based Pickering emulsion could be controllably released in line with actual application demands, and the relatively high viscosity of emulsion could effectively avoid the loss of pesticide during spraying to the target. [Display omitted] [ABSTRACT FROM AUTHOR]