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1.
J Agric Food Chem ; 72(20): 11295-11307, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38717296

RESUMO

The advancement of science and technology, coupled with the growing environmental consciousness among individuals, has led to a shift in pesticide development from traditional methods characterized by inefficiency and misuse toward a more sustainable and eco-friendly approach. Cellulose, as the most abundant natural renewable resource, has opened up a new avenue in the field of biobased drug carriers by developing cellulose-based drug delivery systems. These systems offer unique advantages in terms of deposition rate enhancement, modification facilitation, and environmental impact reduction when designing nanopesticides. Consequently, their application in the field of nanoscale pesticides has gained widespread recognition. The present study provides a comprehensive review of cellulose modification methods, carrier types for cellulose-based nanopesticides delivery systems (CPDS), and various stimulus-response factors influencing pesticide release. Additionally, the main challenges in the design and application of CPDS are summarized, highlighting the immense potential of cellulose-based materials in the field of nanopesticides.


Assuntos
Celulose , Sistemas de Liberação de Medicamentos , Praguicidas , Celulose/química , Praguicidas/química , Sistemas de Liberação de Medicamentos/instrumentação , Portadores de Fármacos/química , Nanopartículas/química
4.
Carbohydr Polym ; 334: 122068, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553197

RESUMO

The fabrication of highly elastic, fatigue-resistant and conductive hydrogels with antibacterial properties is highly desirable in the field of wearable devices. However, it remains challenging to simultaneously realize the above properties within one hydrogel without compromising excellent sensing ability. Herein, we fabricated a highly elastic, fatigue-resistant, conductive, antibacterial and cellulose nanocrystal (CNC) enhanced hydrogel as a sensitive strain sensor by the synergistic effect of biosynthesized selenium nanoparticles (BioSeNPs), MXene and nanocellulose. The structure and potential mechanism to generate biologically synthesized SeNPs (BioSeNPs) were systematically investigated, and the role of protease A (PrA) in enhancing the adsorption between proteins and SeNPs was demonstrated. Additionally, owing to the incorporation of BioSeNPs, CNC and MXene, the synthesized hydrogels showed high elasticity, excellent fatigue resistance and antibacterial properties. More importantly, the sensitivity of hydrogels determined by the gauge factor was as high as 6.24 when a high strain was applied (400-700 %). This study provides a new horizon to synthesize high-performance antibacterial and conductive hydrogels for soft electronics applications.


Assuntos
Nanopartículas , Nitritos , Selênio , Elementos de Transição , Antibacterianos/farmacologia , Celulose/farmacologia , Condutividade Elétrica , Hidrogéis/farmacologia
5.
J Agric Food Chem ; 72(13): 7279-7290, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38519413

RESUMO

PepXLcMY-3, an X-prolyl dipeptidyl aminopeptidase derived from Lactobacillus lactis MY-3, was screened and recombinantly expressed in Escherichia coli. The enzyme could exhibit about 40% activity within the pH range of 6.0-10. To further improve the pH robustness, site E396 located in the active pocket was discovered through alanine scanning. The mutant E396I displayed both developed activity and kcat/Km. The optimal pH of E396I shifted from 6.0 to 10 compared to WT, with the relative activity within the pH range of 6.0-10 significantly increased. The site K648 was then proposed by semirational design. The activity of mutant E396I/K648D reached 4.03 U/mg. The optimal pH was restored to 6.0, and the pH stability was further improved. E396I/K648D could totally hydrolyze ß-casomorphin 7 within 30 min. The hydrolysate showed 64.5% inhibition on angiotensin I converting enzyme, which was more efficient than those produced by E396I and WT, 23.2 and 44.7%, respectively.


Assuntos
Lactococcus lactis , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Sequência de Aminoácidos , Dipeptidil Peptidases e Tripeptidil Peptidases , Peptídeos/genética , Hidrolases , Aminopeptidases/genética , Aminopeptidases/química , Aminopeptidases/metabolismo , Concentração de Íons de Hidrogênio
6.
Int J Biol Macromol ; 264(Pt 1): 130633, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447835

RESUMO

Efficiently addressing the challenge of leakage is crucial in the advancement of solid-liquid phase change thermal storage composite materials; however, numerous existing preparation methods often entail complexity and high energy consumption. Herein, a straightforward blending approach was adopted to fabricate stable phase change nanocomposites capitalizing on the interaction between TEMPO-oxidized cellulose nanofibers (TOCNF) and polyethylene glycol (PEG) molecules. By adjusting the ratio of TOCNF to PEG and the molecular weights of PEG, TOCNF/PEG phase change composites (TPCC) with customizable phase transition temperature (40.3-59.1 °C) and high phase transition latent heat (126.3-172.1 J/g) were obtained. The TPCC of high-loaded PEG (80-95 wt%) ensured a leakage rate of less than 1.7 wt% after 100 heating-cooling cycles. Moreover, TPCC exhibits excellent optical properties with a transmittance of over 90 % at room temperature and up to 96 % after heating. The thermal response analysis of TPCC demonstrates exceptional thermal-induced flexibility and good thermal stability, as well as recyclability and reshaping ability. This study may inspire others to design bio-based phase change composites with potential applications in thermal energy storage and management of smart-energy buildings, photothermal response devices, and waste heat-generating electronics.


Assuntos
Celulose Oxidada , Nanofibras , Celulose , Temperatura Alta , Temperatura , Polietilenoglicóis
7.
J Agric Food Chem ; 72(8): 4257-4266, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38354318

RESUMO

Selenium nanoparticles (SeNPs) are important and safe food and feed additives that can be used for dietary supplementation. In this study, a mutagenic strain of Saccharomyces boulardii was employed to obtain biologically synthesized SeNPs (BioSeNPs) with the desired particle size by controlling the dosage and duration of sodium selenite addition, and the average particle size achieved was 55.8 nm with protease A encapsulation. Transcriptomic analysis revealed that increased expression of superoxide dismutase 1 (SOD1) in the mutant strain effectively promoted the synthesis of BioSeNPs and the formation of smaller nanoparticles. Under sodium selenite stress, the mutant strain exhibited significantly increased expression of glutathione peroxidase 2 (GPx2), which was significantly greater in the mutant strain than in the wild type, facilitating the synthesis of glutathione selenol and providing abundant substrates for the production of BioSeNPs. Furthermore, based on the experimental results and transcriptomic analysis of relevant genes such as sod1, gpx2, the thioredoxin reductase 1 gene (trr1) and the thioredoxin reductase 2 gene (trr2), a yeast model for the size-controlled synthesis of BioSeNPs was constructed. This study provides an important theoretical and practical foundation for the green synthesis of controllable-sized BioSeNPs or other metal nanoparticles with potential applications in the fields of food, feed, and biomedicine.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Saccharomyces boulardii , Selênio , Catálise , Saccharomyces boulardii/metabolismo , Selênio/metabolismo , Selenito de Sódio , Superóxido Dismutase/genética , Superóxido Dismutase-1
8.
Bioresour Technol ; 393: 130056, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37993070

RESUMO

In this study, a combined pretreatment involving autohydrolysis and p-toluenesulfonic acid (p-TsOH) was performed on poplar to coproduce xylooligosaccharides (XOSs) and monosaccharides. The autohydrolysis (180 °C, 30 min) yielded 53.2 % XOS and enhanced the delignification efficiency in the subsequent p-TsOH treatment. Furthermore, considerably high glucan contents (64.1 %∼83.1 %) were achieved in the combined pretreated substrates. However, their enzymatic digestibilities were found to be extremely poor (9.6 %∼14.2 %), which were even lower than the single p-TsOH pretreated substrates (10.2 %∼35.8 %). The underlying reasons were revealed by systematically investigating the effects of the single and combined pretreatment strategies on substrate properties. Moreover, the Tween 80 addition successfully reversed the adverse effects of combined pretreatment on the enzymatic hydrolysis, achieving a high glucose yield of 99.3 % at an enzyme loading of 10 filter paper units/g (FPU/g) glucan. These results deepen the understanding of the synergy of combined pretreatment on biomass fractionation and enzymatic saccharification.


Assuntos
Benzenossulfonatos , Lignina , Populus , Lignina/química , Polissorbatos , Hidrólise , Glucanos , Populus/química
9.
Int J Biol Macromol ; 257(Pt 2): 128712, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38081482

RESUMO

Wheat gluten (WG) shows great promise to synthesize environment-friendly wood adhesives. However, their weak bonding strength and poor water resistance have limited its application in the commercial wood-based panel industry. In this study, a novel WG-based adhesive was developed by constructing a multiple cross-linking network generated by covalent and non-covalent bonds. The potential mechanism was revealed by FT-IR analysis. Furthermore, their surface morphology, thermal stability, viscosity, and residual rate of adhesives with different compositions were systematically characterized and compared. The results showed that the hydrogen bonding, reactions between amine groups and tannin, and ring opening reaction of epoxy, synergistically contributed to generate a highly crosslinked network. The wet/boil water strength of the plywood prepared from WG/tannin/ethylene imine polymer (PEI)-glycerol triglycidyl ether (GTE) adhesive with the addition of 15 % GTE could reach 1.21 MPa and 1.20 MPa, respectively, and a mildew resistance ability was observed. This study provides a facile strategy to fabricate high-performance plant protein-based adhesives with desirable water resistance for practical application.


Assuntos
Glutens , Triticum , Taninos/química , Adesivos/química , Madeira/química , Água/análise , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Eur J Nutr ; 63(3): 697-711, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38147149

RESUMO

PURPOSE: Probiotics have been reported to effectively alleviate hyperuricemia and regulate the gut microbiota. The aim of this work was to study the in vivo anti-hyperuricemic properties and the mechanism of a novel strain, Lactiplantibacillus plantarum X7022. METHODS: Purine content and mRNA expression of purine assimilation related enzymes were determined by HPLC and qPCR, respectively. Hyperuricemic mice were induced by potassium oxonate and hypoxanthine. Uric acid (UA), blood urea nitrogen, creatinine and renal inflammation were examined by kits. The expression of renal UA transporters was subjected to western blotting. Kidney tissues were sectioned for histological analysis. The fecal short-chain fatty acids (SCFAs) were determined by HPLC, and gut microbiota was investigated using the 16S rDNA metagenomic sequencing. RESULTS: L. plantarum X7022 possesses a complete purine assimilation pathway and can exhaust xanthine, guanine, and adenine by 82.1%, 33.1%, and 12.6%, respectively. The strain exhibited gastrointestinal viability as 44% at the dose of 109 CFU/mL in mice. After four-week administration of the strain, a significant decrease of 35.5% in the serum UA level in hyperuricemic mice was achieved. The diminished contents of fecal propionate and butyrate were dramatically boosted. The treatment also alleviated renal inflammation and restored renal damage. The above physiological changes may due to the inhibited xanthine oxidase (XO) activity, as well as the expressional regulation of UA transporters (GLUT9, URAT1 and OAT1) to the normal level. Notably, gut microbiota dysbiosis in hyperuricemic mice was improved with the inflammation and hyperuricemia related flora depressed, and SCFAs production related flora promoted. CONCLUSION: The strain is a promising probiotic strain for ameliorating hyperuricemia.


Assuntos
Microbioma Gastrointestinal , Hiperuricemia , Camundongos , Animais , Hiperuricemia/tratamento farmacológico , Hiperuricemia/induzido quimicamente , Hiperuricemia/metabolismo , Rim/metabolismo , Ácido Úrico , Inflamação/metabolismo
11.
Gels ; 9(9)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37754406

RESUMO

Hydrogels containing renewable resources, such as hemicellulose, have received a lot of attention owing to their softness and electrical conductivity which could be applied in soft devices and wearable equipment. However, traditional hemicellulose-based hydrogels generally exhibit poor electrical conductivity and suffer from freezing at lower temperatures owing to the presence of a lot of water. In this study, we dissolved hemicellulose by employing deep eutectic solvents (DESs), which were prepared by mixing choline chloride and imidazole. In addition, hemicellulose-based DES hydrogels were fabricated via photo-initiated reactions of acrylamide and hemicellulose with N, N'-Methylenebisacrylamide as a crosslinking agent. The produced hydrogels demonstrated high electrical conductivity and anti-freezing properties. The conductivity of the hydrogels was 2.13 S/m at room temperature and 1.97 S/m at -29 °C. The hydrogel's freezing point was measured by differential scanning calorimetry (DSC) to be -47.78 °C. Furthermore, the hemicellulose-based DES hydrogels can function as a dependable and sensitive strain sensor for monitoring a variety of human activities.

12.
Small ; 19(52): e2302335, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37661587

RESUMO

Strong, conductive, and flexible materials with improving ion accessibility have attracted significant attention in electromagnetic interference (EMI) and foldable wearable electronics. However, it still remains a great challenge to realize high performance at the same time for both properties. Herein, a microscale structural design combined with nanostructures strategy to fabricate TOCNF(F)/Ti3 C2 Tx (M)@AgNW(A) composite films via a facile vacuum filtration process followed by hot pressing (TOCNF = TEMPO-oxidized cellulose nanofibrils, NW = nanowires) is described. The comparison reveals that different microscale structures can significantly influence the properties of thin films, especially their electrochemical properties. Impressively, the ultrathin MA/F/MA film with enhanced layer in the middle exhibits an excellent tensile strength of 107.9 MPa, an outstanding electrical conductivity of 8.4 × 106 S m-1 , and a high SSE/t of 26 014.52 dB cm2 g-1 . The assembled asymmetric MA/F/MA//TOCNF@CNT (carbon nanotubes) supercapacitor leads to a significantly high areal energy density of 49.08 µWh cm-2 at a power density of 777.26 µW cm-2 . This study proposes an effective strategy to circumvent the trade-off between EMI performance and electrochemical properties, providing an inspiration for the fabrication of multifunctional films for a wide variety of applications in aerospace, national defense, precision instruments, and next-generation electronics.

13.
Neurologist ; 28(5): 304-309, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37146273

RESUMO

BACKGROUND: Dural arteriovenous fistulas (DAVFs) leading to oedema, primarily in the internal capsule, are extremely rare and, to our knowledge, have never been reported. We reported a case of DAVFs with oedema in bilateral internal capsule oedema and reviewed the literature. METHODS: The report describes a unique imaging presentation of cases of DAVFs as symmetric lesions, mainly in the bilateral internal capsule. It also reviews the literature for symmetric lesions in the internal capsule and central grey matter caused by DAVFs to further characterize this rare entity and differential diagnosis through imaging features. RESULTS: In cases of symmetric oedema caused by DAVFs, the most common artery involved in arterial supply was the middle meningeal artery (13/24; 54%). The main vein involved in the drainage was the Galen vein (18/29; 62%). Most cases were treated with transarterial embolization (23/29; 79%), and the probability of effective treatment or complete cure is 100%. On imaging, the vasogenic oedema signal caused by DAVFs is a symmetrical lesion of the bilateral internal capsule, that is, DWI MRI shows a high signal in the unrestricted diffusion area on the apparent diffusion coefficient map. CONCLUSIONS: MR has good diagnostic value in abnormal basal ganglia symmetric signals caused by DAVFs, and can quickly identify DAVFs early.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Embolização Terapêutica , Humanos , Cápsula Interna/patologia , Malformações Vasculares do Sistema Nervoso Central/complicações , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Resultado do Tratamento , Embolização Terapêutica/métodos , Angiografia Cerebral
14.
Heliyon ; 9(5): e15825, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37180921

RESUMO

To improve the flammability of foamed polyurethane/wood-flour composites (FWPC), ammonium polyphosphate (APP) was used as a flame retardant to modified FWPC. The effects of different flame treatment processes on flame performance, smoke suppression, thermal property, and surface micrographs of flame retardant FWPC were investigated. The results showed that FWPC with the addition or impregnation process both improved the combustion behaviors. Compared with the addition process, FWPC-impregnation (FWPC-I) had a lower total heat release (THR), lower peak heat release rate (PHRR), prolonged time to ignition (TTI), more residues, and better combustion safety. FWPC-I had the highest residual carbon rate reaching 39.98%. A flame-retardant layer containing the P-O group was formed in the residual carbon of FWPC-I. Although APP had negative effects on the physical properties of FWPC, it was an effective flame-retardant ability for foamed polyurethane/wood-flour composites.

15.
Carbohydr Polym ; 312: 120827, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37059554

RESUMO

Stretchable and tough polysaccharide-based functional hydrogels have gained popularity for various applications. However, it still remains a great challenge to simultaneously own satisfactory stretchability and toughness, particularly when incorporating renewable xylan to offer sustainability. Herein, we describe a novel stretchable and tough xylan-based conductive hydrogel utilizing the natural feature of rosin derivative. The effect of different compositions on the mechanical properties and the physicochemical properties of corresponding xylan-based hydrogels were systematically investigated. Owing to the multiple non-covalent interactions among different components to dissipate energies and the strain-induced orientation of rosin derivative during the stretching, the highest tensile strength, strain, and toughness of xylan-based hydrogels could reach 0.34 MPa, 2098.4 %, and 3.79 ± 0.95 MJ/m3, respectively. Furthermore, by incorporating MXene as the conductive fillers, the strength and toughness of hydrogels were further enhanced to 0.51 MPa and 5.95 ± 1.19 MJ/m3. Finally, the synthesized xylan-based hydrogels were able to serve as a reliable and sensitive strain sensor to monitor the movements of human beings. This study provides new insights to develop stretchable and tough conductive xylan-based hydrogel, especially utilizing the natural feature of bio-based resources.


Assuntos
Hidrogéis , Xilanos , Humanos , Condutividade Elétrica , Movimento
16.
Sci Total Environ ; 876: 162549, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-36871707

RESUMO

With rapid socioeconomic development, oil is widely used in all aspects of modern society. However, the extraction, transport, and processing of oil inevitably lead to the production of large quantities of oily wastewater. Traditional oil/water separation strategies are often inefficient, costly, and cumbersome to operate. Therefore, new green, low-cost, and high-efficiency materials must be developed for oil/water separation. As widely sourced and renewable natural biocomposites, wood-based materials have become a hot field recently. This review will focus on the application of several wood-based materials in oil/water separation. The state of research on wood sponges, cotton fibers, cellulose aerogels, cellulose membranes, and some other wood-based materials for oil/water separation over the last few years and provide an outlook on their future development are summarized and investigated. It is expected to provide some direction for future research on the use of wood-based materials in oil/water separation.


Assuntos
Celulose , Lignina , Biomassa , Óleos
17.
Front Bioeng Biotechnol ; 11: 1167123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36994362

RESUMO

In recent years, microbial conversion of inorganic selenium into an efficient and low-toxic form of selenium has attracted much attention. With the improvement of scientific awareness and the continuous progress of nanotechnology, selenium nanoparticles can not only play the unique functions of organic selenium and inorganic selenium but also have higher safety, absorption and biological activity than other selenium forms. Therefore, the focus of attention has gradually shifted beyond the level of selenium enrichment in yeast to the combination of biosynthetic selenium nanoparticles (BioSeNPs). This paper primarily reviews inorganic selenium and its conversion to less toxic organic selenium and BioSeNPs by microbes. The synthesis method and potential mechanism of organic selenium and BioSeNPs are also introduced, which provide a basis for the production of specific forms of selenium. The methods to characterize selenium in different forms are discussed to understand the morphology, size and other characteristics of selenium. In general, to obtain safer and higher selenium content products, it is necessary to develop yeast resources with higher selenium conversion and accumulation.

19.
Molecules ; 28(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36771056

RESUMO

Soy protein isolate (SPI) is an attractive natural material for preparing wood adhesives that has found broad application. However, poor mechanical properties and unfavorable water resistance of wood composites with SPI adhesive bonds limit its more extensive utilization. The combination of lysine (Lys) with a small molecular structure as a curing agent for modified soy-based wood adhesive allows Lys to penetrate wood pores easily and can result in better mechanical strength of soy protein-based composites, leading to the formation of strong chemical bonds between the amino acid and wood interface. Scanning electron microscopy (SEM) results showed that the degree of penetration of the S/G/L-9% adhesive into the wood was significantly increased, the voids, such as ducts of wood at the bonding interface, were filled, and the interfacial bonding ability of the plywood was enhanced. Compared with the pure SPI adhesive, the corresponding wood breakage rate was boosted to 84%. The wet shear strength of the modified SPI adhesive was 0.64 MPa. When Lys and glycerol epoxy resin (GER) were added, the wet shear strength of plywood prepared by the S/G/L-9% adhesive reached 1.22 MPa, which increased by 29.8% compared with only GER (0.94 MPa). Furthermore, the resultant SPI adhesive displayed excellent thermostability. Water resistance of S/G/L-9% adhesive was further enhanced with respect to pure SPI and S/GER adhesives through curing with 9% Lys. In addition, this work provides a new and feasible strategy for the development and application of manufacturing low-cost, and renewable biobased adhesives with excellent mechanical properties, a promising alternative to traditional formaldehyde-free adhesives in the wood industry.


Assuntos
Lisina , Proteínas de Soja , Proteínas de Soja/química , Lisina/análise , Resinas Epóxi/análise , Adesivos/química , Madeira/química , Água/análise
20.
Int J Biol Macromol ; 227: 462-471, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521712

RESUMO

Conductive hydrogels have attracted increasing attention for applications in wearable and flexible strain sensors. However, owing to their relatively weak strength, poor elasticity, and lack of anti-freezing ability, their applications have been limited. Herein, we present a skin-mimicking strategy to fabricate cellulose-enhanced, strong, elastic, highly conductive, and anti-freezing hydrogels. Self-assembly of cellulose to fabricate a cellulose skeleton is essential for realizing a skin-mimicking design. Furthermore, two methods, in situ polymerization and solvent replacement, were compared and investigated to incorporate conductive and anti-freezing components into hydrogels. Consequently, when the same ratio of glycerol and lithium chloride was used, the anti-freezing hydrogels prepared by in situ polymerization showed relatively higher strength (1.0 MPa), while the solvent-replaced hydrogels exhibited higher elastic recovery properties (94.6 %) and conductivity (4.5 S/m). In addition, their potential as strain sensors for monitoring human behavior was analyzed. Both hydrogels produced reliable signals and exhibited high sensitivity. This study provides a new horizon for the fabrication of strain sensors that can be applied in various environments.


Assuntos
Celulose , Hidrogéis , Humanos , Elasticidade , Glicerol , Condutividade Elétrica , Solventes
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