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1.
Int J Biol Macromol ; : 136187, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39357719

RESUMEN

Natural wood has been highly valued for thousands of years due to its excellent strength, low density, and ease of processing. However, its poor water stability, which leads to swelling and deformation, limits its competitiveness. In response, we designed a reconstructed wood through a process involving pretreatment, TEMPO oxidation, lignin self-assembly, lignin melting, and densification. In this material, cellulose serves as the skeleton, while lignin with a phenylpropyl structure acts as both a filler and binder. The resulting wood exhibits outstanding water stability, with no changes after 60 days of water immersion and a water absorption rate as low as 8.32 %. This stability is achieved through the densification of lignin, which is enhanced by lignin melting and pressure during self-assembly. The reconstructed wood not only offers excellent water stability but also boasts superior UV resistance and thermal stability. Additionally, it can be hot-pressed into straws within a mold, providing better water stability and tensile strength compared to paper straws. This reconstructed wood, made from natural wood and corncob, is biodegradable and environmentally friendly, offering a new approach to wood water stability strategies.

2.
MycoKeys ; 109: 31-48, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39359355

RESUMEN

Marasmiellus (Omphalotaceae, Agaricales) specimens collected in Thailand were investigated based on morphological characteristics and molecular phylogenetic analyses. In the present study, two species are introduced as new to science, namely Marasmiellusthailandicus and M.minutisporus. Phylogenetic analyses were carried out based on the internal transcribed spacer (nrITS) and nuclear ribosomal RNA large subunit (nrLSU) regions, and the results revealed that the two new taxa are distinct species within Marasmiellus. Another specimen was identified as M.scandens and is reported for the first time with morphology and molecular data from Thailand. Descriptions, illustrations, and phylogenetic results are provided. In addition, M.diaphanus and M.colocasiae are proposed as new combinations of Collybiopsisdiaphana and Paramarasmiuscolocasiae, respectively, based on the phylogenetic evidence.

3.
Cureus ; 16(8): e68308, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39350848

RESUMEN

Erythrasma is a common chronic superficial bacterial infection caused by Corynebacterium minutissimum, a lipophilic, diphtheroid, filamentous, gram-positive bacillus and normal inhabitant of the skin flora. Commonly found in intertriginous spaces, this bacterium releases a porphyrin that causes lesions to fluoresce under a Wood's lamp, aiding diagnosis. Despite its clinical relevance, the pathogenesis remains understudied. We present a case of a 43-year-old woman with a history of hypertension, type 2 diabetes mellitus, and obesity who exhibited an erythematous eczematous plaque with characteristic coral-red fluorescence under Wood's lamp. The diagnosis was confirmed through negative skin scrapings for candidiasis and dermatophytosis. A two-week course of topical clindamycin resulted in complete resolution. Given the condition's frequent coexistence with other pathologies, accurate diagnosis and effective treatment are essential. Topical treatments are usually more convenient. The hypothesis that hydrophobic and lipophilic interactions in intertriginous areas contribute to the pathogenesis of erythrasma requires further experimental validation.

4.
Ecol Lett ; 27(9): e14527, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39354905

RESUMEN

In tropical forests, trees strategically balance growth patterns to optimise fitness amid multiple environmental stressors. Wind poses the primary risk to a tree's mechanical stability, prompting developments such as thicker trunks to withstand the bending forces. Therefore, a trade-off in resource allocation exists between diameter growth and vertical growth to compete for light. We explore this trade-off by measuring the relative wind mortality risk for 95 trees in a tropical forest in Panama and testing how it varies with tree size, species and wind exposure. Surprisingly, local wind exposure and tree size had minimal impact on wind mortality risk; instead, species wood density emerged as the crucial factor. Low wood density species exhibited a significantly greater wind mortality risk, suggesting a prioritisation of competition for light over biomechanical stability. Our study highlights the pivotal role of wind safety in shaping the life-history strategy of trees and structuring diverse tropical forests.


Asunto(s)
Bosques , Árboles , Clima Tropical , Viento , Árboles/crecimiento & desarrollo , Panamá , Madera
5.
J Wood Sci ; 70(1): 35, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39257695

RESUMEN

Wood constantly interacts with the surrounding, locally varying climate, leading to changes in the moisture content. Advanced simulation tools can predict the two-dimensional moisture distributions caused by these changing climate conditions within wood cross sections over time. However, there is a notable absence of systematic simulation results for diverse climatic conditions and various wood cross sections. This study seeks to bridge this gap in research. Here, we present moisture fields in three solid timber and three glued laminated timber cross sections in Austria and show the effect of the location and the altitude on the moisture content distribution. The results reveal decreasing influence of the location on the moisture content development with increasing cross section size, and primarily the altitude affecting the moisture content. In addition, the results are compared with the standard for the design of timber-concrete composite structures (ONR CEN/TS 19103), revealing appropriate values in most of the cases. Only for cross sections with a width of 14 cm and larger, assigned to a specific region, the standard value is assumed underestimated. Furthermore, the distribution of moisture gradients, which are related to the crack depth development, are analyzed for Austria, demonstrating the influence of mountain areas in the moisture gradient development. Supplementary Information: The online version contains supplementary material available at 10.1186/s10086-024-02147-z.

6.
Sci Rep ; 14(1): 20918, 2024 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251732

RESUMEN

Halophilic archaea are a unique group of microorganisms that thrive in high-salt environments, exhibiting remarkable adaptations to survive extreme conditions. Archaeological wood and El-Hamra Lake serve as a substrate for a diverse range of microorganisms, including archaea, although the exact role of archaea in archaeological wood biodeterioration remains unclear. The morphological and chemical characterizations of archaeological wood were evaluated using FTIR, SEM, and EDX. The degradation of polysaccharides was identified in Fourier transform infrared analysis (FTIR). The degradation of wood was observed through scanning electron microscopy (SEM). The energy dispersive X-ray spectroscopy (EDX) revealed the inclusion of minerals, such as calcium, silicon, iron, and sulfur, into archaeological wood structure during burial and subsequent interaction with the surrounding environment. Archaea may also be associated with detected silica in archaeological wood since several organosilicon compounds have been found in the crude extracts of archaeal cells. Archaeal species were isolated from water and sediment samples from various sites in El-Hamra Lake and identified as Natronococcus sp. strain WNHS2, Natrialba hulunbeirensisstrain WNHS14, Natrialba chahannaoensis strain WNHS9, and Natronococcus occultus strain WNHS5. Additionally, three archaeal isolates were obtained from archaeological wood samples and identified as Natrialba chahannaoensisstrain W15, Natrialba chahannaoensisstrain W22, and Natrialba chahannaoensisstrain W24. These archaeal isolates exhibited haloalkaliphilic characteristics since they could thrive in environments with high salinity and alkalinity. Crude extracts of archaeal cells were analyzed for the organic compounds using gas chromatography-mass spectrometry (GC-MS). A total of 59 compounds were identified, including free saturated and unsaturated fatty acids, saturated fatty acid esters, ethyl and methyl esters of unsaturated fatty acids, glycerides, phthalic acid esters, organosiloxane, terpene, alkane, alcohol, ketone, aldehyde, ester, ether, and aromatic compounds. Several organic compounds exhibited promising biological activities. FTIR spectroscopy revealed the presence of various functional groups, such as hydroxyl, carboxylate, siloxane, trimethylsilyl, and long acyl chains in the archaeal extracts. Furthermore, the archaeal extracts exhibited antioxidant effects. This study demonstrates the potential of archaeal extracts as a valuable source of bioactive compounds with pharmaceutical and biomedical applications.


Asunto(s)
Arqueología , Lagos , Madera , Madera/química , Madera/microbiología , Lagos/microbiología , Egipto , Archaea , Espectroscopía Infrarroja por Transformada de Fourier , Filogenia , Espectrometría por Rayos X
7.
Heliyon ; 10(18): e37433, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39309879

RESUMEN

Natural fiber-reinforced composites are becoming popular day by day because of their low cost and renewable nature. However, a major concern of these composites is water absorption. To minimize the water absorption in natural fiber-reinforced composites, wood varnish coating was used in this paper to investigate the effect of this coating on water absorption and mechanical properties of jute fiber-reinforced composites. Four types of composites were fabricated using the hand lay-up technique, among them on Type 1 no coating was used, Type 2 was surface coated, Type 3 was fiber coated and Type 4 was both fiber and composite surface coated. Water absorption, tensile, bending, short beam shear, and impact tests were performed on the composite specimens according to their respective ASTM standards to see the effect of coating. Both fiber and fracture surface morphology were observed using Scanning Electron Microscope. It was found that the water absorption was significantly reduced for Type 2 (50.31 %) and Type 4 (56.01 %) specimens. However, the tensile strength and bending strength were reduced by 74.17 %, and 72.71 % for Type 3 and 77.07 % and 84.24 % for Type 4 composites while for Type 2, they were slightly increased (7.26 % and 1.13 %). The ILSS of Type 3 and Type 4 were reduced by 69.34 % and 58.07 % respectively while it was reduced by only 4.49 % for Type 2 composite. On the other hand, the impact energy absorption was increased by 85.32 % for Type 4 composite. The findings of this study suggest that Type 2 composite (only composite surface coating) has the overall best performance and wood varnish coating has the potential to reduce the water absorption on natural fiber-reinforced composites.

8.
Small ; : e2404420, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39308234

RESUMEN

Wood, as a renewable material, has been regarded as an emerging substrate for self-supporting electrodes in large-scale water electrolysis due to numerous merits such as rich pore structure, abundant hydroxyl groups, etc. However, poor conductivity of wood can greatly suppress the performance of wood-based electrodes. Carbonization process can improve wood's conductivity, but the loss of hydroxyl groups and the required high energy consumption are the drawbacks of such a process. Here, a facile strategy is developed to prepare pristine wood-supported electrode (Ni-NiP/W) for enhanced hydrogen evolution reaction (HER); this improves electrical conductivity of wood while retaining its excellent intrinsic properties. The preparation process involves the deposition of copper on the untreated wood followed with the loading of Ni-NiP catalyst at room temperature. Encouragingly, the Ni-NiP/W exhibits conductive and inherited pristine wood's superhydrophilic and superaerophobic properties, that effectively boost mass and charge transfer. It demonstrates high activity and excellent stability in acidic, alkali, and seawater conditions as well as high current densities of up to 2000 mA cm-2; particularly a record-low HER overpotential of 206 mV in acidic conditions at 1000 mA cm-2. This work fully unlocks the admiring potential of pristine wood as superior substrate for high-performance electrochemical electrodes.

9.
Heliyon ; 10(18): e37599, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39315190

RESUMEN

In this work, we report the investigation of the effect of exposure of apple trees to the bioeffector wood distillate (WD), a plant biostimulant used for improving the nutritional profiling of crop plants. We measured the effect by evaluating the biochemical and nutritional profile of both pulps and skin of fruits. WD (0.2 %, v/v) was applied once a week by foliar application, from May 2023 until September 2023. The results indicate that the WD-treated apples have a significant increase in several analyzed parameters (i.e., phenols, flavonoids, tannins, total antioxidant power, sugars, pectin, free amino acids, and mineral element content), especially in the pulp. These data were also confirmed by NMR and LC-ESI-MS techniques. This study pointed out that WD could be a handy tool for the cultivation of fruit trees.

10.
Curr For Rep ; 10(5): 386-400, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39301227

RESUMEN

Purpose of Review: Conventional formaldehyde-based adhesives for wood-based composite panels are subject to significant concerns due to their formaldehyde emissions. Over the past decade, the wood adhesive industry has undergone a considerable transformation that is characterized by a major push in bio-adhesive development. Various bio-based materials have been explored to create alternatives to conventional formaldehyde-based adhesives. Moreover, growing interest in circularity has led to increasingly exploiting industrial coproducts and by-products to find innovative solutions. Recent Findings: Industrial production generates many coproducts that can serve as renewable resources to produce eco-friendly materials. These coproducts offer alternative supply sources for material production without encroaching on food production. Many bio-based compounds or coproducts, such as saccharides, proteins, tannins, and lignocellulosic biomass, can also be used to develop bio-based adhesives. As part of ongoing efforts to reduce formaldehyde emissions, new hardeners and crosslinkers are being developed to replace formaldehyde and bio-scavengers. Other alternatives, such as binderless panels, are also emerging. Summary: This review focuses on sources of bio-based material derived from by-products of various industries, which have many advantages and disadvantages when incorporated into adhesives. Modification methods to enhance their properties and performance in wood-based panels are also discussed. Additionally, alternatives for developing low-emission or formaldehyde-free adhesives are addressed, including hardeners, bio-scavengers, and binderless options. Finally, the environmental impact of bio-based adhesives compared to that of synthetic alternatives is detailed.

11.
Bull Environ Contam Toxicol ; 113(4): 40, 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39305385

RESUMEN

Coastal ecosystems are characterized by various human activities with potential adverse impacts. This study aimed to evaluate the potential oxidative stress effects in representative aquatic biota deployed in situ at a sawmill wastes dump (test site) and reference site in a coastal ecosystem for a short term (28 days) period. PAHs and OCPs were analysed using GC-FID and GC-MS respectively in surface water and sediments. Oxidative stress indices (malondialdehyde, glutathione-s-transferase, reduced glutathione, catalase and superoxide dismutase) were evaluated following standard methods in Coptodon guineensis (Guinean Tilapia) and Callinectes amnicola (Blue crab) over a period of 28 days. Sum PAHs in the test site sediments, oxidative stress indices in C. guineensis liver and C. amnicola haemolymph after 28 days exposure were significantly higher (p < 0.0.5) compared to the reference site. The results showed the adverse impacts to biota of sawmill wastes which are continuously burnt at the test site with potential for long-term effects. Sustainable sawmill wastes management at the test site are recommended to sustain life below water (UNSDG 14).


Asunto(s)
Braquiuros , Monitoreo del Ambiente , Estrés Oxidativo , Tilapia , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Ecosistema , Superóxido Dismutasa/metabolismo , Catalasa/metabolismo
12.
Environ Sci Pollut Res Int ; 31(44): 56091-56113, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39251537

RESUMEN

This study focused on investigating thermal degradation behaviors, kinetics, reaction mechanisms, synergistic effects, and thermodynamic parameters of wood sawdust (WSD), linear low-density polyethylene (LLDPE), and their blends (LW1:3, LW1:1, and LW3:1) during co-pyrolysis in a thermogravimetric analyzer (TGA). Thermal behavior exhibited a LW1:3 blend (25 wt.% LLDPE) showing significant mass loss at lower temperatures (150 to 300 °C) compared to the individual feedstocks, such as 150 to 400 °C and 300 to 520 °C for WSD and LLDPE, respectively. The iso-conversional methods (KAS, FWO, and FM) were used to determine the kinetic parameters (Ea and A), and the activation energy drop was highest for the LW1:3 blend. According to the master plots, the third-order reaction (O3), nucleation (P2/3), and diffusional model (D4) were the predominant reaction mechanisms for the co-pyrolysis of the LW1:3, LW1:1, and LW3:1 blend, respectively. The thermodynamic parameters demonstrate that a small amount of plastic addition into WSD can improve the reactivity of the blend, shorten the reaction time, and cause less energy-intensive reactions. The values of ΔH, ΔG, and ΔS also confirmed the co-pyrolysis process's spontaneity and endothermic nature. The Fourier transforms infrared spectrometer (FTIR) spectra of raw feedstock, blends, and their biochar revealed some of the peaks were shifted, the intensity was reduced, and disappearance can happen when the temperature was increased. Using the experimental and theoretical/predicted activation energies, the parity chart illustrates the synergistic effects of co-pyrolysis of different blends, and the LW1:3 blend has a favorable synergistic impact. These results could be helpful in process optimization and designing an effective reactor system for co-pyrolysis.


Asunto(s)
Polietileno , Pirólisis , Termodinámica , Termogravimetría , Madera , Madera/química , Cinética , Polietileno/química
13.
Sensors (Basel) ; 24(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39275484

RESUMEN

As a mature non-destructive testing technology, near-infrared (NIR) spectroscopy can effectively identify and distinguish the structural characteristics of wood. The Wood Defect One-Dimensional Visual Geometry Group 19-Finite Element Analysis (WD-1D-VGG19-FEA) algorithm is used in this study. 1D-VGG19 classifies the near-infrared spectroscopy data to determine the knot area, fiber deviation area, transition area, and net wood area of the solid wood board surface and generates a two-dimensional image of the board surface through inversion. Then, the nonlinear three-dimensional model of wood with defects was established by using the inverse image, and the finite element analysis was carried out to predict the elastic modulus of wood. In the experiment, 270 points were selected from each of the four regions of the wood, totaling 1080 sets of near-infrared data, and the 1D-VGG19 model was used for classification. The results showed that the identification accuracy of the knot area was 95.1%, the fiber deviation area was 92.7%, the transition area was 90.2%, the net wood area was 100%, and the average accuracy was 94.5%. The error range of the elastic modulus prediction of the three-dimensional model established by the VGG19 classification model in the finite element analysis is between 2% and 10%, the root mean square error (RMSE) is about 598. 2, and the coefficient of determination (R2) is 0. 91. This study shows that the combination of the VGG19 algorithm and finite element analysis can accurately describe the nonlinear defect morphology of wood, thus establishing a more accurate prediction model of wood mechanical properties to maximize the use of wood mechanical properties.

14.
Int J Biol Macromol ; 280(Pt 1): 135539, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39276893

RESUMEN

Lentinula edodes has the ability to grow and produce bioactive compounds on industrial by-products. This study aimed to produce B-glucan of cell wall Shiitake on Beechwood Sawdust (BWS) through a two-step procedure, which included fermentation and B-glucan extraction and purification. Shiitake mushrooms are cultivated by solid-state fermentation (SSF) using the Jamas method to increase the purity of B-glucan. The fermented substrate was first separated and then hydrolyzed by sodium hydroxide (NaOH) (10 M, 1 M), followed by acid hydrolysis extraction. The structure and purity of B-glucan were confirmed by FTIR, NMR, and AFM spectroscopy. The fungus used was molecularly identified by the 18 s rRNA method. Shiitake mushroom was produced by SSF using BWS and high purity ß-glucan was extracted from the produced polysaccharide in the amount of 67.33 mg/g. FTIR, NMR, and AFM analyses proved the production of beta-glucan, and based on molecular identification, it was determined that the mushroom used was Lentinula edodes. The results obtained show that SSF is a valuable technology for the production of biomass and polysaccharides by utilizing the strain of L. edodes. To the best of our knowledge, the yield reported is the highest by the strain of L. edodes using SSF.

15.
J Anim Ecol ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39295575

RESUMEN

Understanding the maintenance of genetic variation in reproductive strategies and polymorphisms in the wild requires a comprehensive examination of the complex interactions between genetic basis, behaviour and environmental factors. We tested the association between three colour genotypes and variation in female pheromone signalling and male antennal morphology in the wood tiger moth (Arctia plantaginis). These moths have genetically determined white (WW, Wy) and yellow (yy) hindwings that are linked to mating success and fitness, with heterozygotes (Wy) having an advantage. We hypothesized that attractiveness and reproductive success are correlated, with Wy females being more attractive than the other two genotypes which could contribute to maintaining the polymorphism. Female attractiveness was tested by baiting traps with females of the three colour genotypes both in low- (i.e. field set-up) and in high-population density (i.e. large enclosure set-up). Male's ability to reach females was correlated to their own colour genotype and antennal morphology (length, area and lamellae count). Contrary to our prediction, morph-related reproductive success and attractiveness were not correlated. Heavier Wy females attracted a lower proportion of males compared to WW and yy females. Specifically, an increase in weight corresponded to a decreased Wy but increased yy female attractiveness. yy females were generally more attractive than others likely due to earlier pheromone release. In males, lamellae count and genetic colour morph were linked to the male's ability to locate females. Furthermore, male traits affected their ability to reach females in a context-specific way. Males with denser antennae (i.e. higher lamellae count) and white males reached the females faster than yellows in the enclosure, while yellow males located females faster than whites in the field. Our results indicate that higher yy female attractiveness was likely affected by the combined effect of early pheromone release, female weight and higher population density. Males' searching success was affected by morph-specific behavioural strategies and local population density. Ultimately, the combined effect of genotype-related pheromone signalling strategies of females together with environment-dependent male behaviour affect male response and potentially contribute to maintaining variation in fitness-related traits.

16.
Sci Rep ; 14(1): 21515, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39277676

RESUMEN

Mortise and tenon joint is a key connecting component in timber-framed architecture. Accurately assessing the damage to joints is crucial for the structural design of wooden buildings. This study conducted fatigue tests at three stress levels (70%, 100%, and 130%) based on the maximum stress from static bending tests to analyze the impact of different stress levels on the fatigue performance of mortise and tenon joints. The results showed that the deformation increased as the stress level increased. The energy loss per cycle de-creased and then increased at 130% stress level, and remained essentially constant at 70% and 100% levels. Then, micro-CT scanning was performed on the specimens after fatigue testing. The ambient occlusion algorithm was used to identify the outer boundaries of the tenon, which can distinguish internal cracks from outside air. The sphericity index was used to differentiate between pores and cracks. Three-dimensional visualization analysis was performed on the specimens, and the obtained information on pores and cracks was quantitatively analyzed. The results indicated that deformation and fracture of the tenon were the primary causes of joint damage. The layer-by-layer porosity of the undeformed portion of the tenon remained essentially constant and was lower than that of the fractured region and higher than that of the deformed region. This study analyzed the damage behavior of mortise and tenon joints under different stress levels, contributing to the design and protection of wooden structure buildings.

17.
Int J Biol Macromol ; 279(Pt 4): 135490, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39255882

RESUMEN

Wastewater purification has evolved into a global problem in the face of increasing scarcity of freshwater resources. Photocatalysis technology possesses prominent advantages in treating pollutants in water because of its low cost and mild reaction conditions, which provides an effective way to treat multiple pollutants and reduce membrane fouling. Herein, we combine photocatalysis technology with filtration technology via in situ reduction Bi0 with Bi2SiO5 strategy incorporating a carbonized wood filter to synthesize carbon/Bi2SiO5@Bi bi-functional composite. Thus, simultaneous filtration and photocatalytic degradation of Rhodamine B and tetracycline were achieved. After filtrating for 30 min, the degradation rate of RhB and TC were 94.23 % and 81.39 %, respectively. Especially, the flux of RhB and TC were up to 2162.16 L m-2 h-1 and 1811.32 L m-2 h-1. In addition, the composite filter also has good recyclability and reusability, after 5 cycles, the degradation efficiency of RhB remains at 91 %. This study utilized photocatalytic technology combined with membrane filtration technology to successfully solve the contradiction between catalytic efficiency and water flux, which realized rapid and dynamic removal of organic pollutants from water. Besides, the use of carbonized wood-based materials provides a potential biomass technology for the preparation of bifunctional photocatalytic filters.

18.
J Agric Food Chem ; 72(37): 20592-20602, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39233330

RESUMEN

Barrel aging is a crucial stage that influences the taste of wines and spirits, particularly increasing their sweetness and bitterness. This increase is caused by nonvolatile compounds released from oak wood. To search for such molecules, we performed a taste-guided inductive fractionation protocol using several analytical techniques. By using HRMS and NMR, two new galloylated derivatives were elucidated. Their enzymatic hydrolysis revealed the formation of ß-methyl-γ-octalactone, indicating that they are potential precursors. The taste properties of these isomers revealed a sweet and bitter taste for P-WL-1 and P-WL-2, respectively. An LC-HRMS quantification method was performed to evaluate the influence of aging parameters such as botanical origin and toasting process on their concentrations. Several spirits were also analyzed to confirm their presence in this matrix. These results improve the understanding of the molecular markers responsible for the taste of beverages.


Asunto(s)
Bebidas Alcohólicas , Aromatizantes , Quercus , Gusto , Madera , Quercus/química , Madera/química , Bebidas Alcohólicas/análisis , Aromatizantes/química , Humanos , Lactonas/química , Lactonas/análisis , Estructura Molecular , Espectrometría de Masas , Vino/análisis
19.
Macromol Rapid Commun ; : e2400560, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39319687

RESUMEN

Current wood identification struggles to differentiate white and red oak (Quercus alba and Quercus rubra) due to highly similar microstructures, as demonstrated by morphological microscope analysis. The present research explores lignin composition as a potential discriminating factor. Here, a rapid and sustainable method for extracting high-quality lignin from oak samples using acidic γ-valerolactone (GVL) under mild conditions is described. As-extracted lignin is thoroughly characterized using various analytical methods, and results reveal a distinct structural difference between the lignin from the two species. White oak lignin possesses a unique "Hibbert ketone" unit detectable by nuclear magnetic resonance spectroscopy (NMR), which is absent in red oak lignin. In addition, infrared spectroscopy differentiates the species based on specific carbonyl groups present in their lignin. These findings suggest that identifying the presence of the Hibbert ketone unit in lignin may offer a highly efficient and reliable method for differentiating white and red oak, opening new avenues for wood identification.

20.
Antioxidants (Basel) ; 13(9)2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39334774

RESUMEN

From a circular bio-economy perspective, biomass valorization requires the implementation of increasingly efficient extraction techniques to ensure the environmental and economic sustainability of biorefining processes. This research focuses on optimizing the specialized metabolite extraction of Turkey oak chips from Quercus cerris L. by applying a 3 levels Full Factorial Design (FFD). The goal is to obtain an extract with the highest antioxidant activity [evaluated by 1,1-diphenyl-2-picryl hydrazyl (DPPH) scavenging activity and ferric reducing antioxidant power (FRAP) assays] and specialized metabolites content [measured as total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC), and hydrolysable tannins content (THC)]. With this objective, three different variables were investigated and compared: temperature (20 °C, 50 °C, 80 °C), solvents EtOH/H2O (0%, 20%, 40%), and time (3 h, 6 h, 24 h), resulting in 27 different extracts. Following the FFD analysis, the optimal extractive conditions were determined to be 80 °C, 40% EtOH/H2O, and 19.8 h. Finally, the prediction ability of FFD was compared with that of artificial neural network (ANN) for DPPH scavenging activity, FRAP, and TPC data based on the coefficient of determination (R2), mean absolute error (MAE), and root mean square error (RMSE). The results indicated that ANN predictions were more precise than FFD ones; however, both methods were useful in optimizing the extraction process as they returned comparable optimized extraction parameters.

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