In order to manufacture environmentally friendly particle boards and enhance local resources, the lignins of Sorghum bicolor and Andropogon gayanus characterized using RMN 13C and MALDI TOF have the same structures. T...In order to manufacture environmentally friendly particle boards and enhance local resources, the lignins of Sorghum bicolor and Andropogon gayanus characterized using RMN 13C and MALDI TOF have the same structures. They contents Guaiacyl (G), Syringyl (S), p-hydroxyphenylpropane (H) and functional groups of phenols, flavonoids and secondary alcohols. The total phenol content determinated using Folin-Ciocalteu reagent is respectively 20.97 and 15.42 mg eqgallic acid/g of extract. The power of their adhesives is different. The Internal Bond (IB) of particleboards manufactured with these adhesives are respectively 0.37 MPa and 0.41 MPa. These lignins can be used as antioxydants.展开更多
Lignins were isolated and purified from alkali treated prehydrolysate of corn stover. The paper presents the structural features of lignins in a series purification processes. Fourier transform infrared spectroscopy, ...Lignins were isolated and purified from alkali treated prehydrolysate of corn stover. The paper presents the structural features of lignins in a series purification processes. Fourier transform infrared spectroscopy, ultraviolet-vis spectroscopy and proton nuclear magnetic resonance spectroscopy were used to analyze the chemical structure. Thermogravimetric analysis was applied to follow the thermal degradation, and wet chemical method was used to determine the sugar content. The results showed that the crude lignin from the prehydrolysate of corn stover was a heterogeneous material of syringyl, guaiacyl and p-hydroxyphenyl units, containing associated polysaccharides, lipids, and melted salts. Some of the crude lignin was chemically linked to hemicelluloses （mainly xylan）. The lipids in crude lignin were probably composed of saturated and/or unsaturated long carbon chains, fatty acids, tdterpenols, waxes, and derivatives of aromatic. The sugar content of purified lignin was less than 2.11%, mainly composed of guaiacyl units. DTGmax of purified lignin was 359 ℃. The majority of the hydroxyl groups were phenolic hydroxyl groups. The main type of linkages in purified lignin was β-O-4. Other types of linkages included β-5, β-β and α-O-4.展开更多
Brassica crops,which are of worldwide importance,provide various oil,vegetable and ornamental products,as well as feedstocks for animal husbandry and biofuel industry.Cinnamoyl-Co A reductase(CCR)is the entry point to...Brassica crops,which are of worldwide importance,provide various oil,vegetable and ornamental products,as well as feedstocks for animal husbandry and biofuel industry.Cinnamoyl-Co A reductase(CCR)is the entry point to the lignin pathway and a crucial locus in manipulation of associated traits,but CCRassociated metabolism and traits in Brassica crops have remained largely unstudied except in Arabidopsis thaliana.We report the identification of 16 CCR genes from Brassica napus and its parental species B.rapa and B.oleracea.The Bn CCR1 and Bn CCR2 subfamilies displayed divergent organ-specificity and participation in the yellow-seed trait.Their functions were dissected via overexpression of representative paralogs in B.napus.Bn CCR1 was expressed preferentially in G-and H-lignin biosynthesis and vascular development,while Bn CCR2 was expressed in S-lignin biosynthesis and interfascicular fiber development.Bn CCR1 showed stronger effects on lignification-related development,lodging resistance,phenylpropanoid flux control,and seed coat pigmentation,whereas Bn CCR2 showed a stronger effect on sinapate biosynthesis.Bn CCR1 upregulation delayed bolting and flowering time,while Bn CCR2 upregulation weakened the leaf vascular system in consequence of suppressed G-lignin accumulation.Bn CCR1 and Bn CCR2 were closely but almost oppositely linked with glucosinolate metabolism via inter-pathway crosstalk.We conclude that Bn CCR1 and Bn CCR2 subfamilies offer great but differing potential for manipulating traits associated with phenylpropanoids and glucosinolates.This study reveals the CCR1–CCR2 divergence in Brassicaceae and offers a resource for rapeseed breeding for lodging resistance,yellowseed traits,and glucosinolate traits.展开更多
In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were c...In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were characterized by Fourier transform infrared spectroscopy(FT-IR) and 1D and 2D Nuclear Magnetic Resonance(NMR).FT-IR spectra revealed that the "core" of the lignin structure did not significantly change during the treatment under the conditions given.The results of 1H and 13C NMR demonstrated that the lignin fraction L2,isolated with 70% ethanol containing 1% NaOH,was mainly composed of β-O-4 ether bonds together with G and S units and trace p-hydroxyphenyl unit.Based on the 2D HSQC NMR spectrum,the ethanol organosolv lignin fraction L1,extracted with 70% ethanol,presents a predominance of β-O-4′ aryl ether linkages(61% of total side chains),and a low abundance of condensed carbon-carbon linked structures(such as ββ′,β-1′,and β-5′) and a lower S/G ratio.Furthermore,a small percentage(ca.9%) of the linkage side chain was found to be acylated at the γ-carbon.展开更多
Pyrolytic lignin, the water-insoluble fraction in bio-oil, often shows a high content and has strong intermolecular interactions with other compounds in bio-oil. In order to obtain pure pyrolytic lignin and facilitate...Pyrolytic lignin, the water-insoluble fraction in bio-oil, often shows a high content and has strong intermolecular interactions with other compounds in bio-oil. In order to obtain pure pyrolytic lignin and facilitate the utilization of aqueous phase obtained from water extraction of bio-oil, methanol–water extraction method was employed to further separate the bio-oil water-insoluble phase in this paper. Different technologies, including Fourier transform infrared spectroscopy, gel permeation chromatography, and nuclear magnetic resonance, were adopted to characterize the structures of pyrolytic lignins with different activities obtained through this method. Both the heating value and the polymerization degree of high-molecular-weight pyrolytic lignin were higher than those of low-molecular-weight pyrolytic lignin. The molecular weight distribution of high-molecular-weight pyrolytic lignin was relatively wider, among which the contents of dimers to pentamers all accounted for 12% –18%,while the low-molecular-weight pyrolytic lignin mainly consisted of trimers(75.38%). The pyrolytic lignins had similar basic structures, both of which contained syringyl and guaiacyl units, whereas the low-molecular-weight pyrolytic lignin had more abundant syringyl units, reactive carbonyl groups and hydroxyl groups. Meanwhile,thermogravimetric study revealed that the final char residue yield of low-molecular-weight pyrolytic lignin was lower than that of high-molecular-weight pyrolytic lignin.展开更多
<span style="line-height:1.5;font-family:Verdana;">In the present work</span><span style="line-height:1.5;font-family:Verdana;">,</span><span "="" style=&q...<span style="line-height:1.5;font-family:Verdana;">In the present work</span><span style="line-height:1.5;font-family:Verdana;">,</span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;"> lignin is isolated from three different agro-industrial waste, sweet sorghum, rice straw and sugarcane bagasse using </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;"> sodium hydroxide-sodium bisulfate methodology. Characterization was performed using fourier transform infrared analysis (FTIR), scan electron microscopy (SEM), thermo gravimetric analysis (TGA). The SEM micrographs showed sponge-like structure except for sugarcane bagasse lignin reveals rock-like structure. The FTIR indicates the presence of hydroxyl, carbonyl and methoxyl groups in the lignin structure. TGA thermograms were relatively same and sugarcane bagasse lignin was found the most thermally stable up to 201<span style="white-space:nowrap;">˚</span>C as compared to both of soda and kraft sugarcane bagasse lignin and its maximal temperature degradation rate DTG</span><sub><span style="font-family:Verdana;">max</span></sub><span style="font-family:Verdana;"> was found at 494<span style="white-space:nowrap;">˚</span>C while 450<span style="white-space:nowrap;">˚</span>C, 464<span style="white-space:nowrap;">˚</span>C in addition to thermal stabilities up to 173<span style="white-space:nowrap;">˚</span>C and 180<span style="white-space:nowrap;">˚</span>C for sweet sorghum and rice straw lignins respectively. All lignins exhibited low percentage of bio-char less than 10% remained unvalotilized at the end of the thermogravimetric analysis at 800<span style="white-space:nowrap;">˚</span>C in nitrogen atmosphere</span></span><span style="line-height:1.5;font-family:Verdana;">,</span><span style="line-height:1.5;font-family:Verdana;"> reveal</span><span style="line-height:1.5;font-family:Verdana;">ing</span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;"> a high conversion yield into volatiles. Moreover, all lignin samples depicted higher cytotoxic potential towards lung cancer cell line (A549), IC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;">: 12</span></span><span "="" style="line-height:1.5;"> </span><span style="line-height:1.5;font-family:Verdana;">-</span><span "="" style="line-height:1.5;"> </span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;">17 μg/ml. These findings suggest that the </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;"> separated lignins would be good candidates for pyrolysis, polymer composites preparations and seem to be promising natural anti-cancer agents despite its main utilization as </span></span><span style="line-height:1.5;font-family:Verdana;">the</span><span style="line-height:1.5;font-family:Verdana;"> caner drug delivery substrates.展开更多
Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a ...Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a hydrothermal method.The HDO performance of the catalysts was evaluated using 4-ethylguaiacol as a model compound at 340℃ under 3 MPa H2.The MoS_(2)/NC catalyst exhibited a deoxygenation degree of 83.4%,whereas the Fe-modified catalyst(Fe_(0.3)MoS/NC)attained complete deoxygenation(100%)with an arenes selectivity of 78.6%.Beyond the optimal ratio,the deoxygenation degree is inversely proportional to the Fe/Mo molar ratio.The catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),low-temperature nitrogen adsorption(BET method)and X-ray photoelectron spectroscopy(XPS).The characterization results indicated that the introduction of Fe enhanced the uniform dispersion of MoS_(2)on the NC support surface.This modification further increased the acidity of the catalyst surface and raised the concentration of sulfur vacancies,thereby promoting the adsorption of oxygencontaining compounds.Furthermore,the HDO performance of the Fe_(0.3)MoS/NC catalyst was evaluated using actual lignin as a feedstock under the conditions of 340℃,3 MPa H2 and 12 h.The results showed a green hydrocarbon yield of 65.5%,of which the C_(8)-C_(16)fraction accounted for 54.4%of the total hydrocarbons.Within this fraction,aromatic compounds constituted 63.4%,suggesting its potential use as green aviation fuel-range arenes.This work thus establishes a viable catalytic pathway for efficient conversion of lignin to arenes.展开更多
The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different cont...The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different contents(20%,30%,and 40%)were used to prepare the starch-urea-lignin(SUL)and starch-urea-oxidized lignin(SUOL)resin.Sodium persulfate(SPS)as oxidizer was employed to oxidize both starch and lignin.Urea was just used as a low cost and effective crosslinker in the resin composition.The properties of the synthesized resins and the plywood panels bonded with themweremeasured according to relevant standards.The viscosity and gel time of the SUOL resins containing oxidized lignin are respectively higher and faster than for non-modified lignin(SUL).The lignin phenolic hydroxyl groups(-OH)proportion was markedly increased by oxidation as shown by Fourier Transform Infrared(FTIR)spectrometry.The molecular mass and the polydispersity of the lignin did also decrease by its oxidization pretreatment.DSC analysis showed a decrease of the glass transition temperature of the lignin(Tg)due to its oxidation.The thermal analysis of the oxidized lignin SUOL resin also showed that it had a lower peak temperature than the SUL equivalent non-modified lignin resin.The plywood panels bonded with oxidized lignin gave acceptable bending modulus,bending strength,peak temperature by thermal analysis and dry shear strength as well as a better plywood dimensional stability when used in the SUOL formulation.The synthesized SUOL adhesive is a lignin-derived,totally bio,no-aldehyde added,inexpensive resin applicable to bond plywood.展开更多
The increasing scarcity of freshwater resources has driven the rapid emergence of solar-driven interfacial evaporators(SDIEs)as a sustainable approach to harvest fresh water by utilizing solar energy.Lignocellulosic b...The increasing scarcity of freshwater resources has driven the rapid emergence of solar-driven interfacial evaporators(SDIEs)as a sustainable approach to harvest fresh water by utilizing solar energy.Lignocellulosic biomass,featuring natural abundance,excellent renewability,unique natural structures,and superior biodegradability compared to the synthetic polymers,is highly attractive for constructing solar steam generators.This review aims to offer an innovative and in-depth insight into designing and optimizing highperformance integrated solar interfacial evaporators derived from renewable lignocellulosic biomass.First,the structural characteristics of lignocellulosic biomass are briefly introduced,serving as photothermal layer or supporting substrates in SDIEs.Secondly,the fabrication methods and processing technologies of lignocellulosic biomass-based evaporators are summarized from the perspective of photothermal layer and supporting substrates.Next,the most recent advances of regulation and optimization strategies are proposed to improve evaporation efficiency.Subsequently,this review summarizes the diverse functionalities of SDIEs,including desalination,power generation,wastewater treatment and antimicrobial,atmospheric water harvesting,and photocatalytic hydrogen production.Finally,the challenges in this field and outlook on the future development are discussed,which are anticipated to provide new opportunities for the advancement of lignocellulosic biomass-based SDIEs.展开更多
Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent resea...Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.展开更多
Optically pure chiral chemicals are important building blocks with widespread applications across mul-tiple scientific and industrial do-mains such as in pharmaceuticals,agrochemicals,and food,especially acting as pre...Optically pure chiral chemicals are important building blocks with widespread applications across mul-tiple scientific and industrial do-mains such as in pharmaceuticals,agrochemicals,and food,especially acting as precursors to synthesize biodegradable polymers.As an al-ternative to fossil resources,renew-able lignocellulosic biomass has been used to access chiral chemicals,due to the versatile inherent stere-ostructures and multiple functional groups,such as hydroxyl,carbonyl,and phenyl ether groups.Typically,as the two main units of(hemi)cel-lulose components in lignocellulosic biomass,D-xylose and D-glucose bear multiple chiral centers(e.g.,2R-3S-4R for D-xylose and 2R-3S-4R-5R for D-glucose).Lignin bearsβ-O-4 linkages,exhibiting(R,S/S,R)or(R,R/S,S)stereocenters at the side-chainαandβcarbon atoms.The valorization of biomass into optical-ly pure chiral chemicals is vital for developing a more sustainable future.This review discuss-es the production of typical chiral chemicals derived from biomass through chemocatalysis,including lactones(e.g.,R/S-valerolactone),carboxylic acids(e.g.,D/L-glyceric acid,D/L-lactic acid),polyols(e.g.,tetrose),furans,oligosaccharides,and others.Two strategies are generally employed.One approach involves first producing achiral platform chemicals from biomass,followed by the introduction of asymmetric catalysts to reconstruct stereocenters.The second relates to selectively preserving one or more inherent stereocenters in the natural biomass structure during complex cascade reactions in which biomass feedstock acts as a“chi-ral pool",thus eliminating the establishment of stereocenter.The feedstock,methods em-ployed,and enantioselectivity and applications of the target chiral chemicals are discussed.Despite these advances,the synthesis of optically pure chemicals from biomass is still in its in-fancy.The coming decade presents both extraordinary challenges and opportunities in biomass-derived chiral chemistry.Future research should be focused on:(1)integrating well-established asymmetric catalysis techniques and methods with biomass’s inherent chiral pools,presenting an unprecedented opportunity to expand the chemical space of sustainable chiral compounds;(2)mastering polyfunctional complexity of chiral chemicals through holis-tic utilization of biomass’multichiral centers;(3)unlocking lignin’s stereochemical treasury that represents the next frontier in biomass valorization.展开更多
This study evaluates the stabilizing effect of lignin, extracted from Eucalyptus globulus, on an energetic composite of nitrated cellulose carbamate (NCC) plasticized with diethylene glycol dinitrate (DEGDN), compared...This study evaluates the stabilizing effect of lignin, extracted from Eucalyptus globulus, on an energetic composite of nitrated cellulose carbamate (NCC) plasticized with diethylene glycol dinitrate (DEGDN), compared to conventional stabilizers 2-nitrodiphenylamine (2-NDPA) and 1,3-dimethyl-1,3-diphenylurea (C-II). FTIR analysis confirms lignin's capacity to scavenge nitroxyl radicals formed during thermolysis of nitrocarbamate and nitrate ester bonds, thereby inhibiting decomposition. Moreover, the incorporation of C-II, 2-NDPA, and lignin significantly raised the peak temperature of the main thermolysis, as confirmed by DSC and TGA, indicating a progressive stability enhancement in the order: NCC/DEGDN < NCC/DEGDN/C-II < NCC/DEGDN/lignin < NCC/DEGDN/2-NDPA. Additionally, the effect of each stabilizer on the decomposition pathway was characterized by TGA-FTIR. The findings show that stabilizer type significantly affects the intensity of gaseous products released during decomposition without altering their nature. Notably, NH2 groups formed during NCC degradation play a key role in nitrogen conversion, particularly by reducing toxic NO emissions.展开更多
Plant-related organic compound(PROC) may interact with redox-active metals like iron while they are present in soil or aquatic environment, but their effects on the photoreduction of Fe(Ⅲ) remain largely unexplored. ...Plant-related organic compound(PROC) may interact with redox-active metals like iron while they are present in soil or aquatic environment, but their effects on the photoreduction of Fe(Ⅲ) remain largely unexplored. This study investigates the photochemical behavior of Fe(Ⅲ)-PROC complexes using alkaline lignin(AL), betaine hydrochloride(BH), and phytic acid(PA) as representative proxies for PROC. The reductive agent AL demonstrated the ability to directly reduce Fe(Ⅲ) to Fe(Ⅱ). In contrast, BH, being unable to form strong complexes with Fe(Ⅲ), was able to quench·OH, thereby resulting in a shift of the redox equilibrium towards Fe(Ⅱ). PA exhibited a strong binding affinity for Fe(Ⅲ), effectively inhibiting its photoreduction. Electron paramagnetic resonance(EPR) analysis, utilizing 5,5-dimethyl-1-pyrroline-N-oxide(DMPO) as a spin trap, revealed that the DMPO-OH signal detected in photolyzed Fe(Ⅲ)-PROC solutions originated from various pathways. Specifically, uncomplexed Fe(Ⅲ) in AL or BH solutions was shown to oxidize DMPO directly, leading to the formation of a false DMPO-OH adduct. The addition of ethanol to the photolyzed Fe(Ⅲ)-AL and Fe(Ⅲ)-BH systems resulted in the generation of the DMPO-CH(CH_(3))OH adduct, thereby confirming the presence of authentic·OH in these systems. The photolysis of the Fe(Ⅲ)-PA complex may proceed via a photodissociation mechanism, where the resulting loosely bound Fe(Ⅲ)can oxidize DMPO, followed by a nucleophilic attack from water. This research highlights the multifaceted roles of PROC in facilitating the redox cycling of iron within soil and aquatic ecosystems.展开更多
Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmn...Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.展开更多
Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,whil...Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential.展开更多
Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional w...Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional water purification remains elusive.Herein,we report a versatile solvent-fractionation to construct heteroatom-doped multicolor lignin carbon quantum dots(CQDs)with the functions of bimodal pollutant sensing,metal-ionic visualization,and photocatalytic antibiotic dissociation.With the aid of oxidation cleavage and biphasic extraction,the underlying lignin features of molecular weight and functional linkages influence the quantum size and core-surface state of CQDs conferring the unique optical-structure-performance.The N,S co-doped blue-emitting CQDs via light-quenching offer the selective identification of Fe^(3+)-ions in a broad response range with an acceptable limit of detection.The addition of L-cysteine can efficiently restore the fluorescence of CQDs by forming a stable Fe^(3+)-L-cys complex.The green-emissive CQDs are facilely embedded into cellulose hydrogel to directly visualize the presence of metal-ions.A red-CQDs modified ternary ZnIn2S4(ZIS)composite is fabricated to achieve photocatalytic antibiotic removal with an efficiency of~85%.The excellent photo-generated electron and storage capabilities of CQDs improve the light-capturing,electron conduction,and charge carrier separation of ZIS.The reactive species are of importance to photocatalytic tetracycline oxidation,wherein the electron holes(h+)function as the main contributor followed by∙O_(2)^(-),1O2 and∙OH.The directly interfacial electron escaping-shuttling with the help of optimized electronic and energy-band structures is confirmed via electrochemical test and theoretical computation.We anticipate that the present work not only sheds substantial light to manipulate polychromatic lignin-based CQDs via a tailored solvent-engineering,but also presents an emerging green route of emphasizing biomass-water nexus.展开更多
Hydrodeoxygenation represents a promising route for upgrading lignin-derived bio-oil into value-added fine chemicals,but it is challenging to obtain high yield and selectivity due to the varying dissociation energy of...Hydrodeoxygenation represents a promising route for upgrading lignin-derived bio-oil into value-added fine chemicals,but it is challenging to obtain high yield and selectivity due to the varying dissociation energy of different oxygen-containing functional groups.Here,we strategically engineered a robust Cu-based catalyst for catalyzing vanillin to 4-methylguaiacol in a H-donor solvent under an inert N_(2) atmosphere,achieving simultaneously>99.9%conversion and near-theoretical selectivity(99.6%),as well as excellent cycling durability.First-principles calculations and control catalytic experiments confirmed the enhanced performance originated from(i)the downshifted d-band center of in situ generated Cu^(0) species induced by Al Lewis acid sites and(ii)the synergistic interplay between these Cu^(0) centers and adjacent Al Lewis acid sites,facilitated by isopropanol-mediated hydrogen transfer.This study demonstrates the feasibility of rationally designing high-performance catalysts featuring synergistic nonnoble metals with Lewis acid sites,enabling efficient and selective upgrade of renewable peroxidized compounds into value-added products with enhanced cost-effectiveness and process safety.展开更多
Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassi...Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassium fertilization interactively influence lignin biosynthesis in oil flax stems require further investigation.Therefore,this study aimed to enhance lodging resistance and increase grain yield in oil flax.We examined the interactive effects of different nitrogen (75,150,and 225 kg N ha^(–1)) and potassium (60 and 90 kg K_(2)O ha^(–1)) fertilizer rates on lignin metabolism,lodging resistance,and grain yield during the 2022 and 2023 growing seasons.Results indicated that nitrogen and potassium fertilizer levels and their interactions promoted lignin accumulation,improved lodging resistance,and increased grain yield.Compared to the control (CK),the75–150 kg N ha^(–1) combined with 60 kg K_(2)O ha^(–1) treatments significantly enhanced the activities of key lignin-synthesizing enzymes (tyrosine ammonia-lyase (TAL),phenylalanine ammonia-lyase (PAL),cinnamyl alcohol dehydrogenase (CAD),and peroxidase (POD)) and upregulated the expression of 4CL1 and F5H3 genes,leading to a 29.63–43.30%increase in lignin content,improved stem bending strength and lodging resistance index,and a 23.27–32.34%increase in grain yield.Correlation analysis revealed that nitrogen and potassium fertilizers positively regulated enzyme activities and gene expression related to lignin biosynthesis,thereby facilitating lignin accumulation and enhancing stem mechanical strength and lodging resistance.Positive correlations were observed among lignin-related enzyme activities,gene expression,lodging resistance traits,and grain yield.In summary,the application of 75–150 kg N ha^(–1) in conjunction with 60 kg K_(2)O ha^(–1)promoted lignin biosynthesis and accumulation,enhanced lodging resistance,and increased grain yield in oil flax grown in the dryland farming region of central Gansu,China.Furthermore,this treatment provides a technical basis for cultivating stress-tolerant and high-yield oil flax in arid regions.展开更多
With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin...With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.展开更多
The emission of organic pollutants from the dye industry and medical treatment represents a significant threat to the quality of water resources and human health.The development of green,environmentally friendly and e...The emission of organic pollutants from the dye industry and medical treatment represents a significant threat to the quality of water resources and human health.The development of green,environmentally friendly and efficient photocatalysts for the removal of organic pollutants from the environment is of paramount importance in addressing these issues.Flower-like lignin-derived carbon(LC)/zinc oxide(ZnO)composites with controllable morphology were synthesized via a direct precipitation method.In this study,alkali lignin was employed as an anionic active agent to alter the molecular arrangement on the liquid surface during the synthesis reaction and to reduce the surface tension between mixtures,thereby forming a special stacked morphology,which was then used for the highly efficient removal of methylidene blue(MB)and tetracycline hydrochloride(TCH)in water under different light conditions.The formation mechanism of LC/ZnO and the degradation characteristics under different reaction conditions were investigated.The loading of LC can form composites with large specific surface area and rich porous structure.In addition,with the help of lignin,the morphology of ZnO was changed from a rod-like structure to a lamellar structure,and LC could effectively reduce the band gap of ZnO,which could improve the electron transfer rate in the photocatalytic process.The·O_(2)^(-)and·OH radicals generated under photoexcitation promoted the decomposition of pollutants.This study presents a simple,economical,and scalable method for the application of photocatalysts and explores new ways for the high-value application of industrial lignin.展开更多
文摘In order to manufacture environmentally friendly particle boards and enhance local resources, the lignins of Sorghum bicolor and Andropogon gayanus characterized using RMN 13C and MALDI TOF have the same structures. They contents Guaiacyl (G), Syringyl (S), p-hydroxyphenylpropane (H) and functional groups of phenols, flavonoids and secondary alcohols. The total phenol content determinated using Folin-Ciocalteu reagent is respectively 20.97 and 15.42 mg eqgallic acid/g of extract. The power of their adhesives is different. The Internal Bond (IB) of particleboards manufactured with these adhesives are respectively 0.37 MPa and 0.41 MPa. These lignins can be used as antioxydants.
基金Supported by the National Natural Science Foundation of China （20876078, 21176124）, the National High Technology Research and Development Program of China （2011AA02A207）, the National Basic Research Program of China （2009CB724700）, the Key Program of the National Natural Science Foundation of China （20936002）, and the Independent Innovation Project of Jiangsu Province （CX（11）2051）.
文摘Lignins were isolated and purified from alkali treated prehydrolysate of corn stover. The paper presents the structural features of lignins in a series purification processes. Fourier transform infrared spectroscopy, ultraviolet-vis spectroscopy and proton nuclear magnetic resonance spectroscopy were used to analyze the chemical structure. Thermogravimetric analysis was applied to follow the thermal degradation, and wet chemical method was used to determine the sugar content. The results showed that the crude lignin from the prehydrolysate of corn stover was a heterogeneous material of syringyl, guaiacyl and p-hydroxyphenyl units, containing associated polysaccharides, lipids, and melted salts. Some of the crude lignin was chemically linked to hemicelluloses （mainly xylan）. The lipids in crude lignin were probably composed of saturated and/or unsaturated long carbon chains, fatty acids, tdterpenols, waxes, and derivatives of aromatic. The sugar content of purified lignin was less than 2.11%, mainly composed of guaiacyl units. DTGmax of purified lignin was 359 ℃. The majority of the hydroxyl groups were phenolic hydroxyl groups. The main type of linkages in purified lignin was β-O-4. Other types of linkages included β-5, β-β and α-O-4.
基金National Natural Science Foundation of China(31871549,32001579,31830067and 31171177)National Key Research and Development Program of China(2016YFD0100506)+2 种基金Special Financial Aid to Post-doctor Research Fellow of Chongqing(Xm T2018057)“111”Project(B12006)Young Eagles Program of Chongqing Municipal Commission of Education(CY200215)。
文摘Brassica crops,which are of worldwide importance,provide various oil,vegetable and ornamental products,as well as feedstocks for animal husbandry and biofuel industry.Cinnamoyl-Co A reductase(CCR)is the entry point to the lignin pathway and a crucial locus in manipulation of associated traits,but CCRassociated metabolism and traits in Brassica crops have remained largely unstudied except in Arabidopsis thaliana.We report the identification of 16 CCR genes from Brassica napus and its parental species B.rapa and B.oleracea.The Bn CCR1 and Bn CCR2 subfamilies displayed divergent organ-specificity and participation in the yellow-seed trait.Their functions were dissected via overexpression of representative paralogs in B.napus.Bn CCR1 was expressed preferentially in G-and H-lignin biosynthesis and vascular development,while Bn CCR2 was expressed in S-lignin biosynthesis and interfascicular fiber development.Bn CCR1 showed stronger effects on lignification-related development,lodging resistance,phenylpropanoid flux control,and seed coat pigmentation,whereas Bn CCR2 showed a stronger effect on sinapate biosynthesis.Bn CCR1 upregulation delayed bolting and flowering time,while Bn CCR2 upregulation weakened the leaf vascular system in consequence of suppressed G-lignin accumulation.Bn CCR1 and Bn CCR2 were closely but almost oppositely linked with glucosinolate metabolism via inter-pathway crosstalk.We conclude that Bn CCR1 and Bn CCR2 subfamilies offer great but differing potential for manipulating traits associated with phenylpropanoids and glucosinolates.This study reveals the CCR1–CCR2 divergence in Brassicaceae and offers a resource for rapeseed breeding for lodging resistance,yellowseed traits,and glucosinolate traits.
基金Major State Basic Research Projects of China(973-2010CB732204)Specific Programs in Graduate Science and Technology Innovation of Beijing Forestry University(BLYJ201110)
文摘In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were characterized by Fourier transform infrared spectroscopy(FT-IR) and 1D and 2D Nuclear Magnetic Resonance(NMR).FT-IR spectra revealed that the "core" of the lignin structure did not significantly change during the treatment under the conditions given.The results of 1H and 13C NMR demonstrated that the lignin fraction L2,isolated with 70% ethanol containing 1% NaOH,was mainly composed of β-O-4 ether bonds together with G and S units and trace p-hydroxyphenyl unit.Based on the 2D HSQC NMR spectrum,the ethanol organosolv lignin fraction L1,extracted with 70% ethanol,presents a predominance of β-O-4′ aryl ether linkages(61% of total side chains),and a low abundance of condensed carbon-carbon linked structures(such as ββ′,β-1′,and β-5′) and a lower S/G ratio.Furthermore,a small percentage(ca.9%) of the linkage side chain was found to be acylated at the γ-carbon.
基金Supported by the National Science and Technology Supporting Plan Through Contract(2015BAD15B06)the National Natural Science Foundation of China(51276166)+1 种基金the National Basic Research Program of China(2013CB228101)Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization(2013A061401005)
文摘Pyrolytic lignin, the water-insoluble fraction in bio-oil, often shows a high content and has strong intermolecular interactions with other compounds in bio-oil. In order to obtain pure pyrolytic lignin and facilitate the utilization of aqueous phase obtained from water extraction of bio-oil, methanol–water extraction method was employed to further separate the bio-oil water-insoluble phase in this paper. Different technologies, including Fourier transform infrared spectroscopy, gel permeation chromatography, and nuclear magnetic resonance, were adopted to characterize the structures of pyrolytic lignins with different activities obtained through this method. Both the heating value and the polymerization degree of high-molecular-weight pyrolytic lignin were higher than those of low-molecular-weight pyrolytic lignin. The molecular weight distribution of high-molecular-weight pyrolytic lignin was relatively wider, among which the contents of dimers to pentamers all accounted for 12% –18%,while the low-molecular-weight pyrolytic lignin mainly consisted of trimers(75.38%). The pyrolytic lignins had similar basic structures, both of which contained syringyl and guaiacyl units, whereas the low-molecular-weight pyrolytic lignin had more abundant syringyl units, reactive carbonyl groups and hydroxyl groups. Meanwhile,thermogravimetric study revealed that the final char residue yield of low-molecular-weight pyrolytic lignin was lower than that of high-molecular-weight pyrolytic lignin.
文摘<span style="line-height:1.5;font-family:Verdana;">In the present work</span><span style="line-height:1.5;font-family:Verdana;">,</span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;"> lignin is isolated from three different agro-industrial waste, sweet sorghum, rice straw and sugarcane bagasse using </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;"> sodium hydroxide-sodium bisulfate methodology. Characterization was performed using fourier transform infrared analysis (FTIR), scan electron microscopy (SEM), thermo gravimetric analysis (TGA). The SEM micrographs showed sponge-like structure except for sugarcane bagasse lignin reveals rock-like structure. The FTIR indicates the presence of hydroxyl, carbonyl and methoxyl groups in the lignin structure. TGA thermograms were relatively same and sugarcane bagasse lignin was found the most thermally stable up to 201<span style="white-space:nowrap;">˚</span>C as compared to both of soda and kraft sugarcane bagasse lignin and its maximal temperature degradation rate DTG</span><sub><span style="font-family:Verdana;">max</span></sub><span style="font-family:Verdana;"> was found at 494<span style="white-space:nowrap;">˚</span>C while 450<span style="white-space:nowrap;">˚</span>C, 464<span style="white-space:nowrap;">˚</span>C in addition to thermal stabilities up to 173<span style="white-space:nowrap;">˚</span>C and 180<span style="white-space:nowrap;">˚</span>C for sweet sorghum and rice straw lignins respectively. All lignins exhibited low percentage of bio-char less than 10% remained unvalotilized at the end of the thermogravimetric analysis at 800<span style="white-space:nowrap;">˚</span>C in nitrogen atmosphere</span></span><span style="line-height:1.5;font-family:Verdana;">,</span><span style="line-height:1.5;font-family:Verdana;"> reveal</span><span style="line-height:1.5;font-family:Verdana;">ing</span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;"> a high conversion yield into volatiles. Moreover, all lignin samples depicted higher cytotoxic potential towards lung cancer cell line (A549), IC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;">: 12</span></span><span "="" style="line-height:1.5;"> </span><span style="line-height:1.5;font-family:Verdana;">-</span><span "="" style="line-height:1.5;"> </span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;">17 μg/ml. These findings suggest that the </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;"> separated lignins would be good candidates for pyrolysis, polymer composites preparations and seem to be promising natural anti-cancer agents despite its main utilization as </span></span><span style="line-height:1.5;font-family:Verdana;">the</span><span style="line-height:1.5;font-family:Verdana;"> caner drug delivery substrates.
基金Supported by grants from National Key Research and Development Program of China(2024YFB4205903)the National Natural Science Foundation of China(52274308,U22B20144,22278440 and 22078362)Shandong Provincial Technology Innovation Guidance Plan(YDZX2023060)。
文摘Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a hydrothermal method.The HDO performance of the catalysts was evaluated using 4-ethylguaiacol as a model compound at 340℃ under 3 MPa H2.The MoS_(2)/NC catalyst exhibited a deoxygenation degree of 83.4%,whereas the Fe-modified catalyst(Fe_(0.3)MoS/NC)attained complete deoxygenation(100%)with an arenes selectivity of 78.6%.Beyond the optimal ratio,the deoxygenation degree is inversely proportional to the Fe/Mo molar ratio.The catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),low-temperature nitrogen adsorption(BET method)and X-ray photoelectron spectroscopy(XPS).The characterization results indicated that the introduction of Fe enhanced the uniform dispersion of MoS_(2)on the NC support surface.This modification further increased the acidity of the catalyst surface and raised the concentration of sulfur vacancies,thereby promoting the adsorption of oxygencontaining compounds.Furthermore,the HDO performance of the Fe_(0.3)MoS/NC catalyst was evaluated using actual lignin as a feedstock under the conditions of 340℃,3 MPa H2 and 12 h.The results showed a green hydrocarbon yield of 65.5%,of which the C_(8)-C_(16)fraction accounted for 54.4%of the total hydrocarbons.Within this fraction,aromatic compounds constituted 63.4%,suggesting its potential use as green aviation fuel-range arenes.This work thus establishes a viable catalytic pathway for efficient conversion of lignin to arenes.
基金funded by Semnan University,research grant No.226/1403/T140211.
文摘The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different contents(20%,30%,and 40%)were used to prepare the starch-urea-lignin(SUL)and starch-urea-oxidized lignin(SUOL)resin.Sodium persulfate(SPS)as oxidizer was employed to oxidize both starch and lignin.Urea was just used as a low cost and effective crosslinker in the resin composition.The properties of the synthesized resins and the plywood panels bonded with themweremeasured according to relevant standards.The viscosity and gel time of the SUOL resins containing oxidized lignin are respectively higher and faster than for non-modified lignin(SUL).The lignin phenolic hydroxyl groups(-OH)proportion was markedly increased by oxidation as shown by Fourier Transform Infrared(FTIR)spectrometry.The molecular mass and the polydispersity of the lignin did also decrease by its oxidization pretreatment.DSC analysis showed a decrease of the glass transition temperature of the lignin(Tg)due to its oxidation.The thermal analysis of the oxidized lignin SUOL resin also showed that it had a lower peak temperature than the SUL equivalent non-modified lignin resin.The plywood panels bonded with oxidized lignin gave acceptable bending modulus,bending strength,peak temperature by thermal analysis and dry shear strength as well as a better plywood dimensional stability when used in the SUOL formulation.The synthesized SUOL adhesive is a lignin-derived,totally bio,no-aldehyde added,inexpensive resin applicable to bond plywood.
基金supported by grants from National Natural Science Foundation of China(224708046,22508229,22278049)Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)+1 种基金Xingliao Talent Program-Young Top Talent(XLYC2403126)Liaoning Provincial Basic Scientific Research Project for Higher Education(LJ212510152013)。
文摘The increasing scarcity of freshwater resources has driven the rapid emergence of solar-driven interfacial evaporators(SDIEs)as a sustainable approach to harvest fresh water by utilizing solar energy.Lignocellulosic biomass,featuring natural abundance,excellent renewability,unique natural structures,and superior biodegradability compared to the synthetic polymers,is highly attractive for constructing solar steam generators.This review aims to offer an innovative and in-depth insight into designing and optimizing highperformance integrated solar interfacial evaporators derived from renewable lignocellulosic biomass.First,the structural characteristics of lignocellulosic biomass are briefly introduced,serving as photothermal layer or supporting substrates in SDIEs.Secondly,the fabrication methods and processing technologies of lignocellulosic biomass-based evaporators are summarized from the perspective of photothermal layer and supporting substrates.Next,the most recent advances of regulation and optimization strategies are proposed to improve evaporation efficiency.Subsequently,this review summarizes the diverse functionalities of SDIEs,including desalination,power generation,wastewater treatment and antimicrobial,atmospheric water harvesting,and photocatalytic hydrogen production.Finally,the challenges in this field and outlook on the future development are discussed,which are anticipated to provide new opportunities for the advancement of lignocellulosic biomass-based SDIEs.
基金supported by the National Natural Science Foundation of China(21706052,22278114)Natural Science Foundation of Henan Province(242300421575).
文摘Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.
基金supported by the National Natural Sci-ence Foundation of China(Nos.22478263,22308230)Natural Science Foundation of Sichuan(No.2024NSF-SC1134)+2 种基金China Postdoctoral Science Foundation(No.2024T170612)111 center(B17030)the Fun-damental Research Funds for the Central Universities.
文摘Optically pure chiral chemicals are important building blocks with widespread applications across mul-tiple scientific and industrial do-mains such as in pharmaceuticals,agrochemicals,and food,especially acting as precursors to synthesize biodegradable polymers.As an al-ternative to fossil resources,renew-able lignocellulosic biomass has been used to access chiral chemicals,due to the versatile inherent stere-ostructures and multiple functional groups,such as hydroxyl,carbonyl,and phenyl ether groups.Typically,as the two main units of(hemi)cel-lulose components in lignocellulosic biomass,D-xylose and D-glucose bear multiple chiral centers(e.g.,2R-3S-4R for D-xylose and 2R-3S-4R-5R for D-glucose).Lignin bearsβ-O-4 linkages,exhibiting(R,S/S,R)or(R,R/S,S)stereocenters at the side-chainαandβcarbon atoms.The valorization of biomass into optical-ly pure chiral chemicals is vital for developing a more sustainable future.This review discuss-es the production of typical chiral chemicals derived from biomass through chemocatalysis,including lactones(e.g.,R/S-valerolactone),carboxylic acids(e.g.,D/L-glyceric acid,D/L-lactic acid),polyols(e.g.,tetrose),furans,oligosaccharides,and others.Two strategies are generally employed.One approach involves first producing achiral platform chemicals from biomass,followed by the introduction of asymmetric catalysts to reconstruct stereocenters.The second relates to selectively preserving one or more inherent stereocenters in the natural biomass structure during complex cascade reactions in which biomass feedstock acts as a“chi-ral pool",thus eliminating the establishment of stereocenter.The feedstock,methods em-ployed,and enantioselectivity and applications of the target chiral chemicals are discussed.Despite these advances,the synthesis of optically pure chemicals from biomass is still in its in-fancy.The coming decade presents both extraordinary challenges and opportunities in biomass-derived chiral chemistry.Future research should be focused on:(1)integrating well-established asymmetric catalysis techniques and methods with biomass’s inherent chiral pools,presenting an unprecedented opportunity to expand the chemical space of sustainable chiral compounds;(2)mastering polyfunctional complexity of chiral chemicals through holis-tic utilization of biomass’multichiral centers;(3)unlocking lignin’s stereochemical treasury that represents the next frontier in biomass valorization.
文摘This study evaluates the stabilizing effect of lignin, extracted from Eucalyptus globulus, on an energetic composite of nitrated cellulose carbamate (NCC) plasticized with diethylene glycol dinitrate (DEGDN), compared to conventional stabilizers 2-nitrodiphenylamine (2-NDPA) and 1,3-dimethyl-1,3-diphenylurea (C-II). FTIR analysis confirms lignin's capacity to scavenge nitroxyl radicals formed during thermolysis of nitrocarbamate and nitrate ester bonds, thereby inhibiting decomposition. Moreover, the incorporation of C-II, 2-NDPA, and lignin significantly raised the peak temperature of the main thermolysis, as confirmed by DSC and TGA, indicating a progressive stability enhancement in the order: NCC/DEGDN < NCC/DEGDN/C-II < NCC/DEGDN/lignin < NCC/DEGDN/2-NDPA. Additionally, the effect of each stabilizer on the decomposition pathway was characterized by TGA-FTIR. The findings show that stabilizer type significantly affects the intensity of gaseous products released during decomposition without altering their nature. Notably, NH2 groups formed during NCC degradation play a key role in nitrogen conversion, particularly by reducing toxic NO emissions.
基金supported by the Natural Science Foundation of Shanghai(No.24ZR1419600).
文摘Plant-related organic compound(PROC) may interact with redox-active metals like iron while they are present in soil or aquatic environment, but their effects on the photoreduction of Fe(Ⅲ) remain largely unexplored. This study investigates the photochemical behavior of Fe(Ⅲ)-PROC complexes using alkaline lignin(AL), betaine hydrochloride(BH), and phytic acid(PA) as representative proxies for PROC. The reductive agent AL demonstrated the ability to directly reduce Fe(Ⅲ) to Fe(Ⅱ). In contrast, BH, being unable to form strong complexes with Fe(Ⅲ), was able to quench·OH, thereby resulting in a shift of the redox equilibrium towards Fe(Ⅱ). PA exhibited a strong binding affinity for Fe(Ⅲ), effectively inhibiting its photoreduction. Electron paramagnetic resonance(EPR) analysis, utilizing 5,5-dimethyl-1-pyrroline-N-oxide(DMPO) as a spin trap, revealed that the DMPO-OH signal detected in photolyzed Fe(Ⅲ)-PROC solutions originated from various pathways. Specifically, uncomplexed Fe(Ⅲ) in AL or BH solutions was shown to oxidize DMPO directly, leading to the formation of a false DMPO-OH adduct. The addition of ethanol to the photolyzed Fe(Ⅲ)-AL and Fe(Ⅲ)-BH systems resulted in the generation of the DMPO-CH(CH_(3))OH adduct, thereby confirming the presence of authentic·OH in these systems. The photolysis of the Fe(Ⅲ)-PA complex may proceed via a photodissociation mechanism, where the resulting loosely bound Fe(Ⅲ)can oxidize DMPO, followed by a nucleophilic attack from water. This research highlights the multifaceted roles of PROC in facilitating the redox cycling of iron within soil and aquatic ecosystems.
文摘Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.
基金supported by the National Natural Science Foundation of China(Nos.51603005,52403186 and 52573150)Fujian Provincial Natural Science Foundation of China(No.2024J011447)+1 种基金Natural Science Foundation of Xiamen,China(No.3502Z20227305)the Postdoctoral Fellowship Program of CPSF(No.GZC20240095)。
文摘Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential.
基金the National Natural Science Foundation of China(32171728 and 22008159)Wuhan Knowledge Innovation Project(2022020801020312).
文摘Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional water purification remains elusive.Herein,we report a versatile solvent-fractionation to construct heteroatom-doped multicolor lignin carbon quantum dots(CQDs)with the functions of bimodal pollutant sensing,metal-ionic visualization,and photocatalytic antibiotic dissociation.With the aid of oxidation cleavage and biphasic extraction,the underlying lignin features of molecular weight and functional linkages influence the quantum size and core-surface state of CQDs conferring the unique optical-structure-performance.The N,S co-doped blue-emitting CQDs via light-quenching offer the selective identification of Fe^(3+)-ions in a broad response range with an acceptable limit of detection.The addition of L-cysteine can efficiently restore the fluorescence of CQDs by forming a stable Fe^(3+)-L-cys complex.The green-emissive CQDs are facilely embedded into cellulose hydrogel to directly visualize the presence of metal-ions.A red-CQDs modified ternary ZnIn2S4(ZIS)composite is fabricated to achieve photocatalytic antibiotic removal with an efficiency of~85%.The excellent photo-generated electron and storage capabilities of CQDs improve the light-capturing,electron conduction,and charge carrier separation of ZIS.The reactive species are of importance to photocatalytic tetracycline oxidation,wherein the electron holes(h+)function as the main contributor followed by∙O_(2)^(-),1O2 and∙OH.The directly interfacial electron escaping-shuttling with the help of optimized electronic and energy-band structures is confirmed via electrochemical test and theoretical computation.We anticipate that the present work not only sheds substantial light to manipulate polychromatic lignin-based CQDs via a tailored solvent-engineering,but also presents an emerging green route of emphasizing biomass-water nexus.
基金supported by the National Natural Science Foundation of China(No.22278047,No.22208038,No.22508030,and No.22208040)Fundamental Research Funds for the Universities of Liaoning Province(No.LJ212410152038,No.LJBKY2025057No.2025-BS-0463)。
文摘Hydrodeoxygenation represents a promising route for upgrading lignin-derived bio-oil into value-added fine chemicals,but it is challenging to obtain high yield and selectivity due to the varying dissociation energy of different oxygen-containing functional groups.Here,we strategically engineered a robust Cu-based catalyst for catalyzing vanillin to 4-methylguaiacol in a H-donor solvent under an inert N_(2) atmosphere,achieving simultaneously>99.9%conversion and near-theoretical selectivity(99.6%),as well as excellent cycling durability.First-principles calculations and control catalytic experiments confirmed the enhanced performance originated from(i)the downshifted d-band center of in situ generated Cu^(0) species induced by Al Lewis acid sites and(ii)the synergistic interplay between these Cu^(0) centers and adjacent Al Lewis acid sites,facilitated by isopropanol-mediated hydrogen transfer.This study demonstrates the feasibility of rationally designing high-performance catalysts featuring synergistic nonnoble metals with Lewis acid sites,enabling efficient and selective upgrade of renewable peroxidized compounds into value-added products with enhanced cost-effectiveness and process safety.
基金funded by the National Natural Science Foundation of China (31760363)the Earmarked Fund for CARS (CARS-14-1-16)+1 种基金the Gansu Education Science and Technology Innovation Industry Support Program,China (2021CYZC-38)the Gansu Provincial Key Laboratory of Arid Land Crop Science,Gansu Agricultural University,China (GSCS-2020-Z6)。
文摘Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassium fertilization interactively influence lignin biosynthesis in oil flax stems require further investigation.Therefore,this study aimed to enhance lodging resistance and increase grain yield in oil flax.We examined the interactive effects of different nitrogen (75,150,and 225 kg N ha^(–1)) and potassium (60 and 90 kg K_(2)O ha^(–1)) fertilizer rates on lignin metabolism,lodging resistance,and grain yield during the 2022 and 2023 growing seasons.Results indicated that nitrogen and potassium fertilizer levels and their interactions promoted lignin accumulation,improved lodging resistance,and increased grain yield.Compared to the control (CK),the75–150 kg N ha^(–1) combined with 60 kg K_(2)O ha^(–1) treatments significantly enhanced the activities of key lignin-synthesizing enzymes (tyrosine ammonia-lyase (TAL),phenylalanine ammonia-lyase (PAL),cinnamyl alcohol dehydrogenase (CAD),and peroxidase (POD)) and upregulated the expression of 4CL1 and F5H3 genes,leading to a 29.63–43.30%increase in lignin content,improved stem bending strength and lodging resistance index,and a 23.27–32.34%increase in grain yield.Correlation analysis revealed that nitrogen and potassium fertilizers positively regulated enzyme activities and gene expression related to lignin biosynthesis,thereby facilitating lignin accumulation and enhancing stem mechanical strength and lodging resistance.Positive correlations were observed among lignin-related enzyme activities,gene expression,lodging resistance traits,and grain yield.In summary,the application of 75–150 kg N ha^(–1) in conjunction with 60 kg K_(2)O ha^(–1)promoted lignin biosynthesis and accumulation,enhanced lodging resistance,and increased grain yield in oil flax grown in the dryland farming region of central Gansu,China.Furthermore,this treatment provides a technical basis for cultivating stress-tolerant and high-yield oil flax in arid regions.
基金supported by Natural Science and Engineering Research Council of Canada(RGPIN-2017-06737)Canada Research Chairs program,the National Key Research and Development Program of China(2017YFD0601005,2022YFD0904201)+1 种基金the National Natural Science Foundation of China(51203075)the China Scholarship Council(Grant No.CSC202208320361).
文摘With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.
基金financial support of the National Natural Science Foundation of China(U23A6005,22038004 and 22178069).
文摘The emission of organic pollutants from the dye industry and medical treatment represents a significant threat to the quality of water resources and human health.The development of green,environmentally friendly and efficient photocatalysts for the removal of organic pollutants from the environment is of paramount importance in addressing these issues.Flower-like lignin-derived carbon(LC)/zinc oxide(ZnO)composites with controllable morphology were synthesized via a direct precipitation method.In this study,alkali lignin was employed as an anionic active agent to alter the molecular arrangement on the liquid surface during the synthesis reaction and to reduce the surface tension between mixtures,thereby forming a special stacked morphology,which was then used for the highly efficient removal of methylidene blue(MB)and tetracycline hydrochloride(TCH)in water under different light conditions.The formation mechanism of LC/ZnO and the degradation characteristics under different reaction conditions were investigated.The loading of LC can form composites with large specific surface area and rich porous structure.In addition,with the help of lignin,the morphology of ZnO was changed from a rod-like structure to a lamellar structure,and LC could effectively reduce the band gap of ZnO,which could improve the electron transfer rate in the photocatalytic process.The·O_(2)^(-)and·OH radicals generated under photoexcitation promoted the decomposition of pollutants.This study presents a simple,economical,and scalable method for the application of photocatalysts and explores new ways for the high-value application of industrial lignin.
