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1.
Carbohydr Polym ; 339: 122261, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823925

RESUMEN

Understanding the distribution and accessibility of polymers within plant cell walls is crucial for addressing biomass recalcitrance in lignocellulosic materials. In this work, Imaging Fourier Transform Infrared (FTIR) and Raman spectroscopy, coupled with targeted chemical treatments, were employed to investigate cell wall polymer distribution in two bamboo species at both tissue and cell wall levels. Tissue-level Imaging FTIR revealed significant disparities in the distribution and chemical activity of cell wall polymers between the fibrous sheath and fibrous strand. At the cell wall level, Imaging Raman spectroscopy delineated a distinct difference between the secondary wall and intercellular layer, with the latter containing higher levels of lignin, hydroxycinnamic acid (HCA), and xylan, and lower cellulose. Mild acidified sodium chlorite treatment led to partial removal of lignin, HCA, and xylan from the intercellular layer, albeit to a lesser extent than alkaline treatment, indicating susceptibility of these polymers to chemical treatment. In contrast, lignin in the secondary wall exhibited limited reactivity to acidified sodium chlorite but was slightly removed by alkaline treatment, suggesting stable chemical properties with slight alkaline intolerance. These findings provide valuable insights into the inherent design mechanism of plant cells and their efficient utilization.


Asunto(s)
Pared Celular , Celulosa , Ácidos Cumáricos , Lignina , Pared Celular/química , Lignina/química , Ácidos Cumáricos/química , Celulosa/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Xilanos/química , Espectrometría Raman/métodos , Sasa/química , Cloruros/química , Polímeros/química
2.
Carbohydr Polym ; 337: 122112, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38710545

RESUMEN

The growing concerns on environmental pollution and sustainability have raised the interest on the development of functional biobased materials for different applications, including food packaging, as an alternative to the fossil resources-based counterparts, currently available in the market. In this work, functional wood inspired biopolymeric nanocomposite films were prepared by solvent casting of suspensions containing commercial beechwood xylans, cellulose nanofibers (CNF) and lignosulfonates (magnesium or sodium), in a proportion of 2:5:3 wt%, respectively. All films presented good homogeneity, translucency, and thermal stability up to 153 °C. The incorporation of CNF into the xylan/lignosulfonates matrix provided good mechanical properties to the films (Young's modulus between 1.08 and 3.79 GPa and tensile strength between 12.75 and 14.02 MPa). The presence of lignosulfonates imparted the films with antioxidant capacity (DPPH radical scavenging activity from 71.6 to 82.4 %) and UV barrier properties (transmittance ≤19.1 % (200-400 nm)). Moreover, the films obtained are able to successfully delay the browning of packaged fruit stored over 7 days at 4 °C. Overall, the obtained results show the potential of using low-cost and eco-friendly resources for the development of sustainable active food packaging materials.


Asunto(s)
Celulosa , Embalaje de Alimentos , Lignina , Lignina/análogos & derivados , Nanocompuestos , Nanofibras , Resistencia a la Tracción , Madera , Xilanos , Embalaje de Alimentos/métodos , Lignina/química , Nanocompuestos/química , Celulosa/química , Celulosa/análogos & derivados , Madera/química , Nanofibras/química , Xilanos/química , Antioxidantes/química , Frutas/química
3.
Molecules ; 29(9)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38731545

RESUMEN

Functional Lyocell fibers gain interest in garments and technical textiles, especially when equipped with inherently bioactive features. In this study, Lyocell fibers are modified with an ion exchange resin and subsequently loaded with copper (Cu) ions. The modified Lyocell process enables high amounts of the resin additive (>10%) through intensive dispersion and subsequently, high uptake of 2.7% Cu throughout the whole cross-section of the fiber. Fixation by Na2CO3 increases the washing and dyeing resistance considerably. Cu content after dyeing compared to the original fiber value amounts to approx. 65% for reactive, 75% for direct, and 77% for HT dyeing, respectively. Even after 50 household washes, a recovery of 43% for reactive, 47% for direct and 26% for HT dyeing is proved. XRD measurements reveal ionic bonding of Cu fixation inside the cellulose/ion exchange resin composite. A combination of the fixation process with a change in Cu valence state by glucose/NaOH leads to the formation of Cu2O crystallites, which is proved by XRD. Cu fiber shows a strong antibacterial effect against Staphylococcus aureus and Klebsiella pneumonia bacteria, even after 50 household washing cycles of both >5 log CFU. In nonwoven blends with a share of only 6% Cu fiber, a strong antimicrobial (CFU > log 5) and full antiviral effectiveness (>log 4) was received even after 50 washing cycles. Time-dependent measurements already show strong antiviral behavior after 30 s. Further, the fibers show an increased die off of the fungal isolate Candida auris with CFU log 4.4, and nonwovens made from 6% Cu fiber share a CFU log of 1.7. Findings of the study predestines the fiber for advanced textile processing and applications in areas with high germ loads.


Asunto(s)
Antibacterianos , Antifúngicos , Antivirales , Cobre , Antifúngicos/farmacología , Antifúngicos/química , Antibacterianos/farmacología , Antibacterianos/química , Antivirales/farmacología , Antivirales/química , Cobre/química , Cobre/farmacología , Celulosa/química , Celulosa/farmacología , Staphylococcus aureus/efectos de los fármacos , Textiles , Pruebas de Sensibilidad Microbiana , Klebsiella pneumoniae/efectos de los fármacos , Lignina/química , Lignina/farmacología , Humanos
4.
Anal Methods ; 16(19): 2983-2996, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38717259

RESUMEN

We have successfully developed a validated high-throughput analysis method for the identification and quantification of native and oxifunctionalized monolignols using direct infusion electrospray ionization tandem mass spectrometry (DI-ESI-MS/MS). Oxifunctionalized monolignols generated through unspecific peroxygenase catalysis present a sustainable alternative to fossil aromatic hydrocarbons. This study emphasizes a sustainable analytical approach for these renewable biocatalytic precursors, addressing challenges such as matrix effects, accuracy, precision, and sensitivity of the method. Our findings demonstrate the potential of overcoming quantification difficulties using DI-ESI-MS. Notably, this analytical methodology represents a novel utilization of DI-ESI-MS/MS in examining monolignols and their functionalization, thereby advancing the exploration of lignin as a valuable and sustainable bioresource.


Asunto(s)
Lignina , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Lignina/química
5.
Bioresour Technol ; 402: 130840, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38750829

RESUMEN

The constant ammonia gas (NH3) and greenhouse gases (GHG) emissions were considered as a deep-rooted problem in composting which caused air pollution and global climate change. To achieve the mitigation of NH3 and GHG, a novel additive derived from wasted straw, with modified structure and functional groups, has been developed. Results showed that the adsorption capacity of modified lignin (ML) for both ammonium and nitrate was significantly increased by 132.5-360.8 % and 313.7-454.3 % comparing with biochar (BC) and phosphogypsum (PG) after reconstructing porous structure and grafting R-COOH, R-SO3H functional groups. The application of ML could reduce 36.3 % NH3 emission during composting compared with control. Furthermore, the synergetic mitigation NH3 and GHG in ML treatment resulted in a reduction of global warming potential (GWP) by 31.0-64.6 % compared with BC and PG. These findings provide evidence that ML can be a feasible strategy to effectively alleviate NH3 and GHG emissions in composting.


Asunto(s)
Amoníaco , Compostaje , Gases de Efecto Invernadero , Lignina , Compostaje/métodos , Lignina/química , Carbón Orgánico/química , Adsorción , Suelo/química , Efecto Invernadero
6.
Molecules ; 29(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38792198

RESUMEN

Supercritical water gasification (SCWG) of lignocellulosic biomass is a promising pathway for the production of hydrogen. However, SCWG is a complex thermochemical process, the modeling of which is challenging via conventional methodologies. Therefore, eight machine learning models (linear regression (LR), Gaussian process regression (GPR), artificial neural network (ANN), support vector machine (SVM), decision tree (DT), random forest (RF), extreme gradient boosting (XGB), and categorical boosting regressor (CatBoost)) with particle swarm optimization (PSO) and a genetic algorithm (GA) optimizer were developed and evaluated for prediction of H2, CO, CO2, and CH4 gas yields from SCWG of lignocellulosic biomass. A total of 12 input features of SCWG process conditions (temperature, time, concentration, pressure) and biomass properties (C, H, N, S, VM, moisture, ash, real feed) were utilized for the prediction of gas yields using 166 data points. Among machine learning models, boosting ensemble tree models such as XGB and CatBoost demonstrated the highest power for the prediction of gas yields. PSO-optimized XGB was the best performing model for H2 yield with a test R2 of 0.84 and PSO-optimized CatBoost was best for prediction of yields of CH4, CO, and CO2, with test R2 values of 0.83, 0.94, and 0.92, respectively. The effectiveness of the PSO optimizer in improving the prediction ability of the unoptimized machine learning model was higher compared to the GA optimizer for all gas yields. Feature analysis using Shapley additive explanation (SHAP) based on best performing models showed that (21.93%) temperature, (24.85%) C, (16.93%) ash, and (29.73%) C were the most dominant features for the prediction of H2, CH4, CO, and CO2 gas yields, respectively. Even though temperature was the most dominant feature, the cumulative feature importance of biomass characteristics variables (C, H, N, S, VM, moisture, ash, real feed) as a group was higher than that of the SCWG process condition variables (temperature, time, concentration, pressure) for the prediction of all gas yields. SHAP two-way analysis confirmed the strong interactive behavior of input features on the prediction of gas yields.


Asunto(s)
Biomasa , Hidrógeno , Lignina , Aprendizaje Automático , Agua , Lignina/química , Agua/química , Hidrógeno/química , Hidrógeno/análisis , Gases/química , Gases/análisis , Algoritmos , Redes Neurales de la Computación , Dióxido de Carbono/química , Dióxido de Carbono/análisis , Máquina de Vectores de Soporte , Metano/química , Metano/análisis
7.
Molecules ; 29(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38792212

RESUMEN

Lignanoids are an active ingredient exerting powerful antioxidant and anti-inflammatory effects in the treatment of many diseases. In order to improve the efficiency of the resource utilization of traditional Chinese medicine waste, Magnolia officinalis Rehder & E.H.Wilson residue (MOR) waste biomass was used as raw material in this study, and a series of deep eutectic solvents (ChUre, ChAce, ChPro, ChCit, ChOxa, ChMal, ChLac, ChLev, ChGly and ChEG) were selected to evaluate the extraction efficiency of lignanoids from MORs. The results showed that the best conditions for lignanoid extraction were a liquid-solid ratio of 40.50 mL/g, an HBD-HBA ratio of 2.06, a water percentage of 29.3%, an extract temperature of 337.65 K, and a time of 107 min. Under these conditions, the maximum lignanoid amount was 39.18 mg/g. In addition, the kinetics of the extraction process were investigated by mathematic modeling. In our antioxidant activity study, high antioxidant activity of the lignanoid extract was shown in scavenging four different types of free radicals (DPPH, ·OH, ABTS, and superoxide anions). At a concentration of 3 mg/mL, the total antioxidant capacity of the lignanoid extract was 1.795 U/mL, which was equal to 0.12 mg/mL of Vc solution. Furthermore, the antibacterial activity study found that the lignanoid extract exhibited good antibacterial effects against six tested pathogens. Among them, Staphylococcus aureus exerted the strongest antibacterial activity. Eventually, the correlation of the lignanoid extract with the biological activity and physicochemical properties of DESs is described using a heatmap, along with the evaluation of the in vitro hypoglycemic, in vitro hypolipidemic, immunomodulatory, and anti-inflammatory activity of the lignanoid extract. These findings can provide a theoretical foundation for the extraction of high-value components from waste biomass by deep eutectic solvents, as well as highlighting its specific significance in natural product development and utilization.


Asunto(s)
Antioxidantes , Biomasa , Magnolia , Magnolia/química , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Disolventes Eutécticos Profundos/química , Lignina/química , Lignina/farmacología , Lignina/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Animales
8.
Molecules ; 29(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38792135

RESUMEN

The hydrolysis and biotransformation of lignocellulose, i.e., biorefinery, can provide human beings with biofuels, bio-based chemicals, and materials, and is an important technology to solve the fossil energy crisis and promote global sustainable development. Biorefinery involves steps such as pretreatment, saccharification, and fermentation, and researchers have developed a variety of biorefinery strategies to optimize the process and reduce process costs in recent years. Lignocellulosic hydrolysates are platforms that connect the saccharification process and downstream fermentation. The hydrolysate composition is closely related to biomass raw materials, the pretreatment process, and the choice of biorefining strategies, and provides not only nutrients but also possible inhibitors for downstream fermentation. In this review, we summarized the effects of each stage of lignocellulosic biorefinery on nutrients and possible inhibitors, analyzed the huge differences in nutrient retention and inhibitor generation among various biorefinery strategies, and emphasized that all steps in lignocellulose biorefinery need to be considered comprehensively to achieve maximum nutrient retention and optimal control of inhibitors at low cost, to provide a reference for the development of biomass energy and chemicals.


Asunto(s)
Biomasa , Lignina , Lignina/química , Hidrólisis , Fermentación , Biocombustibles , Nutrientes/metabolismo
9.
J Biotechnol ; 389: 78-85, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38718873

RESUMEN

In a bid to explore the on-site biorefinery approach for conversion of forestry residues, lignocellulosic biomass into value-added products was studied. The bark white pine wood was subjected to the microwave technique of fast and slow hydrolysis under varying acid and biomass concentrations to produce levulinic acid (LA). The HCl (2% v/v) and plant biomass (1% w/v) were identified as the optimum conditions for fast wood hydrolysis (270 ºC for 12 sec), which led to maximum LA yield of 446.68 g/kgPB. The proposed sustainable approach is mild, quick, and utilized a very low concentration of the HCl for the production of LA. The hydrolysate was used as a medium for Kluyveromyces marxianus growth to produce 2-phenylethanol (2-PE). K. marxianus used 74-95% of furfural from hydrolysate as a co-substrate to grow. The proposed model of the integrated biorefinery is an affordable on-site approach of using forest waste into localized solutions to produce LA and 2-PE.


Asunto(s)
Biomasa , Ácidos Levulínicos , Alcohol Feniletílico , Madera , Ácidos Levulínicos/metabolismo , Madera/química , Madera/metabolismo , Hidrólisis , Alcohol Feniletílico/metabolismo , Kluyveromyces/metabolismo , Kluyveromyces/crecimiento & desarrollo , Lignina/metabolismo , Lignina/química , Pinus/metabolismo , Pinus/química
10.
Bioresour Technol ; 402: 130804, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718904

RESUMEN

Lignin, a complex phenolic polymer crucial for plant structure, is mostly used as fuel but it can be harnessed for environmentally friendly applications. This article explores ozonation as a green method for lignin extraction from lignocellulosic biomass, aiming to uncover the benefits of the extracted lignin. A pilot-scale ozonation reactor was employed to extract lignin from Miscanthus giganteus (a grass variety) and vine shoots (a woody biomass). The study examined the lignin extraction and modification of the fractions and identified the generation of phenolic and organic acids. About 48 % of lignin was successfully extracted from both biomass types. Phenolic monomers were produced, vine shoots yielding fewer monomers than Miscanthus giganteus. Ozonation generated homogeneous lignin oligomers, although their molecular weight decreased during ozonation, with vine shoot oligomers exhibiting greater resistance to ozone. Extracted fractions were stable at 200 °C, despite the low molecular weight, outlining the potential of these phenolic fractions.


Asunto(s)
Lignina , Ozono , Brotes de la Planta , Poaceae , Lignina/química , Poaceae/química , Ozono/química , Ozono/farmacología , Proyectos Piloto , Brotes de la Planta/química , Biomasa , Reactores Biológicos , Peso Molecular , Fenoles
11.
Bioresour Technol ; 402: 130802, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718902

RESUMEN

A cost-effective, and low-energy room-temperature cascade catalytic carbonization strategy is demonstrated for converting lignin into graphite with a high yield of 87 %, a high surface potential of -37 eV and super-hydrophilicity. This super-hydrophilic feature endows the lignin-derived graphite to be dispersed in a variety of polar solvents, which is important for its future applications. Encapsulating of liquid metals with the graphite for electrical circuit patterning on flexible substrates is also advocated. These written patterns show superb conductivity of 4.9 × 106 S/m, offering good performance stability and reliability while being repeatedly stretched, folded, twisted, and bent. This will offer new designs for flexible electronic devices, sensors, and biomedical devices.


Asunto(s)
Grafito , Interacciones Hidrofóbicas e Hidrofílicas , Lignina , Temperatura , Lignina/química , Grafito/química , Catálisis , Carbono/química , Conductividad Eléctrica
12.
Food Chem ; 451: 139479, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38696939

RESUMEN

Lignocellulose constitutes the primary component of dietary fiber. We assessed how fermenting bamboo shoot residue with the medicinal white-rot fungus Inonotus obliquus affected the yield, composition, and functional attributes of dietary fiber by altering bamboo shoot residue lignocellulose's spatial structure and composition. I. obliquus secretes lignocellulolytic enzymes, which effectively enhance the degradation of holocellulose and lignin by 87.8% and 25.5%, respectively. Fermentation led to a more porous structure and reduced crystallinity. The yield of soluble dietary fiber increased from 5.1 g/100 g raw BSR to 7.1 g/100 g 9-day-fermented bamboo shoot residue. The total soluble sugar content of dietary fiber significantly increased from 9.2% to 13.8%, which improved the hydration, oil holding capacity, in vitro cholesterol, sodium cholate, and nitrite adsorption properties of dietary fiber from bamboo shoot residue. These findings confirm that I. obliquus biotransformation is promising for enhancing dietary fiber yield and quality.


Asunto(s)
Fibras de la Dieta , Fermentación , Inonotus , Lignina , Lignina/metabolismo , Lignina/química , Fibras de la Dieta/metabolismo , Fibras de la Dieta/análisis , Inonotus/metabolismo , Inonotus/química , Brotes de la Planta/química , Brotes de la Planta/metabolismo , Sasa/química , Sasa/metabolismo
13.
Int J Biol Macromol ; 268(Pt 1): 131619, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692998

RESUMEN

The plant cell wall is a complex, heterogeneous structure primarily composed of cellulose, hemicelluloses, and lignin. Exploring the variations in these three macromolecules over time is crucial for understanding wood formation to enhance chemical processing and utilization. Here, we comprehensively analyzed the chemical composition of cell walls in the trunks of Pinus tabulaeformis using multiple techniques. In situ analysis showed that macromolecules accumulated gradually in the cell wall as the plant aged, and the distribution pattern of lignin was opposite that of polysaccharides, and both showed heterogenous distribution patterns. In addition, gel permeation chromatography (GPC) results revealed that the molecular weights of hemicelluloses decreased while that of lignin increased with age. Two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance (2D-HSQC NMR) analysis indicated that hemicelluloses mainly comprised galactoglucomannan and arabinoglucuronoxylan, and the lignin types were mainly comprised guaiacyl (G) and p-hydroxyphenyl (H) units with three main linkage types: ß-O-4, ß-ß, and ß-5. Furthermore, the C-O bond (ß-O-4) signals of lignin decreased while the C-C bonds (ß-ß and ß-5) signals increased over time. Taken together, these findings shed light on wood formation in P. tabulaeformis and lay the foundation for enhancing the processing and use of wood and timber products.


Asunto(s)
Pared Celular , Celulosa , Lignina , Pinus , Polisacáridos , Lignina/química , Pinus/química , Pared Celular/química , Polisacáridos/química , Celulosa/química , Peso Molecular , Árboles/química , Espectroscopía de Resonancia Magnética/métodos , Madera/química
14.
Sci Rep ; 14(1): 12387, 2024 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811644

RESUMEN

Chemical processing is among the significant keys to tackle agro-residues utilization field, aiming to obtain value-added materials. Extraction of cellulose nanocrystals (CNCs) is an emerging route to valorize lignocellulosic wastes into high value particles. In this investigation, effect of acidic hydrolysis duration was monitored on size and morphology of obtained crystals; namely: CNCs from Nile roses fibers (NRFs) (Eichhornia crassipes). Different acidic hydrolysis duration range or different characterization techniques set this article apart from relevant literature, including our group research articles. The grinded NRFs were firstly subjected to alkaline and bleaching pretreatments, then acid hydrolysis process was carried out with varied durations ranging from 5 to 30 min. Microcrystalline cellulose (MCC) was used as reference for comparison with NRFs based samples. The extracted CNCs samples were investigated using various techniques such as scanning electron microscopy (SEM), Atomic force microscopy (AFM), Raman spectroscopy, and thermogravimetric (TGA) analysis. The figures gotten from SEM and AFM depicted that NRFs based CNCs appeared as fibril-like shapes, with reduced average size when the NRFs underwent pulping and bleaching processes. This was indicated that the elimination of hemicellulose and lignin components got achieved successfully. This outcome was proven by chemical composition measurements and TGA/DTG curves. On the other hand, AFM-3D images indicated that CNCs topology and surface roughness were mostly affected by increasing hydrolysis durations, besides smooth and homogeneous surfaces were noticed. Moreover, Raman spectra demonstrated that the particle size and crystallinity degree of NRFs based CNCs can be affected by acidic hydrolysis durations and optimum extraction time was found to be 10 min. Thermal stability of extracted CNCs-NRFs and CNCs-MCC was measured by TGA/DTG and the kinetic models were suggested to identify the kinetic parameters of the thermal decomposition of CNCs for each acid hydrolysis duration. Increasing hydrolysis duration promoted thermal stability, particularly for NRFs based CNCs. Results showcased in this article add new perspective to Nile rose nanocellulose and pave down the way to fabricate NRFs based humidity nano-sensors.


Asunto(s)
Celulosa , Eichhornia , Nanopartículas , Celulosa/química , Nanopartículas/química , Eichhornia/química , Eichhornia/metabolismo , Hidrólisis , Microscopía de Fuerza Atómica , Espectrometría Raman , Microscopía Electrónica de Rastreo , Termogravimetría , Lignina/química
15.
Biotechnol Adv ; 73: 108373, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38704106

RESUMEN

Biochemicals are widely used in the medicine and food industries and are more efficient and safer than synthetic chemicals. The amphipathic surfactants can interact with the microorganisms and embed the extracellular metabolites, which induce microbial metabolites secretion and biosynthesis, performing an attractive prospect of promoting the biochemical production. However, the commonness and differences of surfactant-mediated bio-manufacture in various fields are largely unexplored. Accordingly, this review comprehensively summarized the properties of surfactants, different application scenarios of surfactant-meditated bio-manufacture, and the mechanism of surfactants increasing metabolites production. Various biochemical productions such as pigments, amino acids, and alcohols could be enhanced using the cloud point and the micelles of surfactants. Besides, the amphiphilicity of surfactants also promoted the utilization of fermentation substrates, especially lignocellulose and waste sludge, by microorganisms, indirectly increasing the metabolites production. The increase in target metabolites production was attributed to the surfactants changing the permeability and composition of the cell membrane, hence improving the secretion ability of microorganisms. Moreover, surfactants could regulate the energy metabolism, the redox state and metabolic flow in microorganisms, which induced target metabolites synthesis. This review aimed to broaden the application fields of surfactants and provide novel insights into the production of microbial biochemicals.


Asunto(s)
Tensoactivos , Tensoactivos/metabolismo , Tensoactivos/farmacología , Tensoactivos/química , Fermentación , Bacterias/metabolismo , Biotecnología/métodos , Lignina/metabolismo , Lignina/química , Microbiología Industrial/métodos , Aminoácidos/metabolismo
16.
Rapid Commun Mass Spectrom ; 38(14): e9716, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38738638

RESUMEN

RATIONALE: This study overcomes traditional biomass analysis limitations by introducing a pioneering matrix-free laser desorption/ionization (LDI) approach in mass spectrometry imaging (MSI) for efficient lignin evaluation in wood. The innovative acetic acid-peracetic acid (APA) treatment significantly enhances lignin detection, enabling high-throughput, on-site analysis. METHODS: Wood slices, softwood from a conifer tree (Japanese cypress) and hardwood from a broadleaf tree (Japanese beech), were analyzed using MSI with a Fourier transform ion cyclotron resonance mass spectrometer. The developed APA treatment demonstrated effectiveness for MSI analysis of biomass. RESULTS: Our imaging technique successfully distinguishes between earlywood and latewood and enables the distinct visualization of lignin in these and other wood tissues, such as the radial parenchyma. This approach reveals significant contrasts in MSI. It has identified intense ions from ß-O-4-type lignin, specifically in the radial parenchyma of hardwood, highlighting the method's precision and utility in wood tissue analysis. CONCLUSIONS: The benefits of matrix-free LDI include reduced peak overlap, consistent sample quality, preservation of natural sample properties, enhanced analytical accuracy, and reduced operational costs. This innovative approach is poised to become a standard method for rapid and precise biomass evaluation and has important applications in environmental research and sustainable resource management and is crucial for the effective management of diverse biomass, paving the way towards a sustainable, circular society.


Asunto(s)
Biomasa , Lignina , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Madera , Madera/química , Lignina/análisis , Lignina/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Fagus/química
17.
Int J Biol Macromol ; 269(Pt 2): 132147, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38719007

RESUMEN

Lignin in biomass plays significant role in substitution of synthetic polymer and reduction of energy expenditure, and the lignin content was usually determined by wet chemical methods. However, the methods' heavy workload, low efficiency, huge consumption of chemicals and use of toxic reagents render them unsuitable for sustainable development and environmental protection. Chinese fir, a prevalent angiosperm tree, holds immense importance for various industries. Since our previous work found that Raman spectroscopy could accurately predict the lignin content in poplar, we propose that the lignin content of Chinese fir can be estimated by similar strategy. The results suggested that the peak at 2895 cm-1 is the optimal choice of internal standard peak and algorithm of XGBoost demonstrates the highest accuracy among all algorithms. Furthermore, transfer learning was successfully introduced to enhance the accuracy and robustness of the model. Ultimately, we report that a machine learning algorithm, combining transfer learning with XGBoost or LightGBM, offers an accurate, high-efficiency and environmental friendly method for predicting the lignin content of Chinese fir using Raman spectra.


Asunto(s)
Algoritmos , Cunninghamia , Lignina , Aprendizaje Automático , Espectrometría Raman , Lignina/química , Lignina/análisis , Espectrometría Raman/métodos , Cunninghamia/química
18.
Int J Biol Macromol ; 269(Pt 2): 132141, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723809

RESUMEN

To enhance the flame retardancy and mechanical performance of PLA, a polyelectrolyte complex predicated on lignin was obtained by electrostatic mutual adsorption of ammonium polyphosphate (APP), polyethyleneimine (PEI), and copper ions as raw materials. The FT-IR spectra and EDX analysis confirmed the successful synthesis of a lignin-based flame retardant hybrid (APL-Cu2+) containing copper, phosphorus, and nitrogen elements. The combustion test results showed that the peak heat release rate and total heat release of the PLA composite containing 12 wt% APL-Cu2+ were decreased by 15.1 % and 18.2 %, respectively, as compared to those of pure PLA. The char residue morphology observation revealed that the addition of APL-Cu2+ could promote the formation of a highly dense and stable graphitized char layer, while TG-MS detected the emission of refractory gases such as ammonia gas, carbon dioxide, and water during combustion. The strong hydrogen bonding between APL-Cu2+ and the PLA matrix kept the composite maintaining good strength and toughness. The tensile strength and impact strength of PLA/6APL-Cu2+ increased by 4.73 % and 65.71 %, respectively, due to its high crystallinity and good interfacial compatibility. This work provides a feasible method to develop biobased flame retardant hybrids for PLA composites with better fire safety and improved mechanical properties.


Asunto(s)
Cobre , Retardadores de Llama , Lignina , Poliésteres , Lignina/química , Cobre/química , Poliésteres/química , Incendios/prevención & control , Fenómenos Mecánicos , Resistencia a la Tracción , Espectroscopía Infrarroja por Transformada de Fourier , Polietileneimina/química
19.
Int J Biol Macromol ; 269(Pt 2): 132145, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723819

RESUMEN

Sulfonated lignin-based dye dispersants have intensively attracted attention due to their low cost, renewability and abundant sources. However, their utilization is limited by the low content of sulfonic groups and high content of hydroxyl groups in their complex lignin structure, which results in various problems such as high reducing rate of dye, severe staining of the fibers and uneven dyeing. Here, the multi-site sulfonated lignin-based dispersants were prepared with high sulfonic group content (2.20 mmol/g) and low hydroxyl content (2.43 mmol/g). When using it as the dispersant, the dye uptake rate was improved from 69.23 % to 98.55 %, the reducing rate was decreased from 20.82 % to 2.03 %, the K/S value was reduced from 0.69 to 0.02, and the particle sizes in dye system before and after high temperature treatment were stabilized below 0.5 µm. Besides, the dispersion effect was significantly improved because no obvious separation between dye and water was observed even if without the assistance of grinding process. In short, the multi-site sulfonation method proposed in this work could remarkably improve the performances of the lignin-based dye dispersants, which would facilitate the development of the dye dispersion and the high value utilization of lignin.


Asunto(s)
Colorantes , Lignina , Lignina/química , Colorantes/química , Ácidos Sulfónicos/química , Tamaño de la Partícula , Temperatura
20.
Int J Biol Macromol ; 269(Pt 2): 132144, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729476

RESUMEN

Herein, we investigated the synergistic effects of jet milling (JM) and deep eutectic solvent (DES) pretreatment on the fractionation of grapevine lignin and the consequent enhancement of enzymatic hydrolysis. Grapevine, a substantial byproduct of the wine industry, was subjected to JM pretreatment to produce finely powdered particles (median diameter D50 = 98.90), which were then further treated with acidic ChCl-LA and alkaline K2CO3-EG DESs. The results revealed that the combined JM + ChCl-LA pretreatment significantly increased the cellulose preservation under optimal conditions (110 °C, 4 h, and 20 % water content), achieving removal rates of 74.18 % xylan and 66.05 % lignin, respectively. The pretreatment temperature and inhibitor production were reduced, resulting in a remarkable threefold increase in glucose yield compared to untreated samples. Moreover, the structural analysis of the pretreated lignin indicated an enrichment of phenolic units, leading to enhanced antioxidant and antibacterial activities, particularly in the JM pretreated samples. These findings underscore the promising potential of the synergistic JM and DES pretreatment in facilitating the efficient utilization of grapevine lignocellulosic biomass for sustainable biorefinery technologies.


Asunto(s)
Disolventes Eutécticos Profundos , Lignina , Vitis , Lignina/química , Vitis/química , Hidrólisis , Disolventes Eutécticos Profundos/química , Fraccionamiento Químico/métodos , Antioxidantes/química , Antioxidantes/farmacología , Biomasa , Celulosa/química , Celulasa/química , Celulasa/metabolismo , Solventes/química , Temperatura
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