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1.
Microb Cell Fact ; 22(1): 93, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37143012

RESUMO

BACKGROUND: Prolyl endopeptidase from Aspergillus niger (AN-PEP) is a prominent serine proteinase with various potential applications in the food and pharmaceutical industries. However, the availability of efficient and low-cost AN-PEP remains a challenge owing to its low yield and high fermentation cost. RESULTS: Here, AN-PEP was recombinantly expressed in Trichoderma reesei (rAN-PEP) under the control of the cbh1 promoter and its secretion signal. After 4 days of shaking flask cultivation with the model cellulose Avicel PH101 as the sole carbon source, the extracellular prolyl endopeptidase activity reached up to 16.148 U/mL, which is the highest titer reported to date and the secretion of the enzyme is faster in T. reesei than in other eukaryotic expression systems including A. niger and Komagataella phaffii. Most importantly, when cultivated on the low-cost agricultural residue corn cob, the recombinant strain was found to secret a remarkable amount of rAN-PEP (37.125 U/mL) that is twice the activity under the pure cellulose condition. Furthermore, treatment with rAN-PEP during beer brewing lowered the content of gluten below the ELISA kit detection limit (< 10 mg/kg) and thereby, reduced turbidity, which would be beneficial for improving the non-biological stability of beer. CONCLUSION: Our research provides a promising approach for industrial production of AN-PEP and other enzymes (proteins) from renewable lignocellulosic biomass, which provides a new idea with relevant researchers for the utilization of agricultural residues.


Assuntos
Prolil Oligopeptidases , Trichoderma , Prolil Oligopeptidases/metabolismo , Aspergillus niger/metabolismo , Cerveja , Celulose/metabolismo , Fermentação , Trichoderma/metabolismo
2.
World J Microbiol Biotechnol ; 39(7): 184, 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37147463

RESUMO

Biogas, produced in anaerobic digestion, is a sustainable alternative for generating energy from agro-industrial and municipal waste. Information from the microbiota active in the process expands the possibilities for technological innovation. In this study, taxonomic annotations, and functional prediction of the microbial community of the inoculum of two processes were carried out: an industrial unit (pilot-scale urban solid waste plant-IU) and a laboratory-scale reactor fed with swine and cattle waste (LS). The biochemical potential of biogas was obtained using tested inoculum with microcrystalline cellulose, obtaining 682 LN/kgVS (LSC-laboratory scale inoculum and microcrystalline cellulose), and 583 LN/kgVS (IUC-industrial unit inoculum and microcrystalline cellulose), which is equivalent to a recovery of 91.5% of total biogas to LSC. The phyla Synergistota and Firmicutes were more abundant in LS/LSC. In the IU/IUC (treatment of restaurant waste and customs seizures), there was a greater microbiological variety and a predominance of the Bacteroidota, Cloacimonadota, Firmicutes and Caldatribacteriota. The genus Methanosaeta predominated in the process, and it was possible to infer the genes (K01895, K00193 and K00625) related to acetoclastic pathway, as well as endoglucanases that are involved in the metabolism of cellulose (LSC). Terpenoids, polyketides, cofactors, and vitamin metabolism were higher in reactors that received different substrates (IU; IUC). The taxonomic and functional differences revealed the importance of determining the microbiota in the analysis of the potential of an inoculum, combined with the use of microcrystalline cellulose, which can provide optimization information in the production of clean energy.


Assuntos
Biocombustíveis , Microbiota , Animais , Bovinos , Suínos , Anaerobiose , Reatores Biológicos/microbiologia , Microbiota/genética , Celulose/metabolismo , Firmicutes/metabolismo , Metano/metabolismo
3.
Int J Mol Sci ; 24(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37175771

RESUMO

The weak point of ionic liquids is their high viscosity, limiting the maximum polymer concentration in the forming solutions. A low-viscous co-solvent can reduce viscosity, but cellulose has none. This study demonstrates that dimethyl sulfoxide (DMSO), being non-solvent for cellulose, can act as a nominal co-solvent to improve its processing into a nanofiltration membrane by phase inversion. A study of the rheology of cellulose solutions in diluted ionic liquids ([EMIM]Ac, [EMIM]Cl, and [BMIM]Ac) containing up to 75% DMSO showed the possibility of decreasing the viscosity by up to 50 times while keeping the same cellulose concentration. Surprisingly, typical cellulose non-solvents (water, methanol, ethanol, and isopropanol) behave similarly, reducing the viscosity at low doses but causing structuring of the cellulose solution and its phase separation at high concentrations. According to laser interferometry, the nature of these non-solvents affects the mass transfer direction relative to the forming membrane and the substance interdiffusion rate, which increases by four-fold when passing from isopropanol to methanol or water. Examination of the nanofiltration characteristics of the obtained membranes showed that the dilution of ionic liquid enhances the rejection without changing the permeability, while the transition to alcohols increases the permeability while maintaining the rejection.


Assuntos
Líquidos Iônicos , Solventes , Celulose , Dimetil Sulfóxido , 2-Propanol , Metanol , Água , Reologia , Viscosidade
4.
Int J Mol Sci ; 24(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37176008

RESUMO

AA9 lytic polysaccharide monooxygenases (LPMOs) are copper-dependent metalloenzymes that play a major role in cellulose degradation and plant infection. Understanding the AA9 LPMO mechanism would facilitate the improvement of plant pathogen control and the industrial application of LPMOs. Herein, via point mutation, we investigated the role of glycine 2 residue in cellulose degradation by Thermoascus aurantiacus AA9 LPMOs (TaAA9). A computational simulation showed that increasing the steric properties of this residue by replacing glycine with threonine or tyrosine altered the H-bonding network of the copper center and copper coordination geometry, decreased the surface charge of the catalytic center, weakened the TaAA9-substrate interaction, and enhanced TaAA9-product binding. Compared with wild-type TaAA9, G2T-TaAA9 and G2Y-TaAA9 variants showed attenuated copper affinity, reduced oxidative product diversity and decreased substrate Avicel binding, as determined using ITC, MALDI-TOF/TOF MS and cellulose binding analyses, respectively. Consistently, the enzymatic activity and synergy with cellulase of the G2T-TaAA9 and G2Y-TaAA9 variants were lower than those of TaAA9. Hence, the investigated residue crucially affects the catalytic activity of AA9 LPMOs, and we propose that the electropositivity of copper may correlate with AA9 LPMO activity. Thus, the relationship among the amino acid at position 2, surface charge and catalytic activity may facilitate an understanding of the proteins in AA9 LPMOs.


Assuntos
Cobre , Oxigenases de Função Mista , Oxigenases de Função Mista/metabolismo , Cobre/metabolismo , Polissacarídeos/metabolismo , Celulose/metabolismo , Oxirredução
5.
Microb Cell Fact ; 22(1): 103, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208691

RESUMO

BACKGROUND: The filamentous fungus Trichoderma reesei has been used as a host organism for the production of lignocellulosic biomass-degrading enzymes. Although this microorganism has high potential for protein production, it has not yet been widely used for heterologous recombinant protein production. Transcriptional induction of the cellulase genes is essential for high-level protein production in T. reesei; however, glucose represses this transcriptional induction. Therefore, cellulose is commonly used as a carbon source for providing its degraded sugars such as cellobiose, which act as inducers to activate the strong promoters of the major cellulase (cellobiohydrolase 1 and 2 (cbh1 and cbh2) genes. However, replacement of cbh1 and/or cbh2 with a gene encoding the protein of interest (POI) for high productivity and occupancy of recombinant proteins remarkably impairs the ability to release soluble inducers from cellulose, consequently reducing the production of POI. To overcome this challenge, we first used an inducer-free biomass-degrading enzyme expression system, previously developed to produce cellulases and hemicellulases using glucose as the sole carbon source, for recombinant protein production using T. reesei. RESULTS: We chose endogenous secretory enzymes and heterologous camelid small antibodies (nanobody) as model proteins. By using the inducer-free strain as a parent, replacement of cbh1 with genes encoding two intrinsic enzymes (aspartic protease and glucoamylase) and three different nanobodies (1ZVH, caplacizumab, and ozoralizumab) resulted in their high secretory productions using glucose medium without inducers such as cellulose. Based on signal sequences (carrier polypeptides) and protease inhibitors, additional replacement of cbh2 with the nanobody gene increased the percentage of POI to about 20% of total secreted proteins in T. reesei. This allowed the production of caplacizumab, a bivalent nanobody, to be increased to 9.49-fold (508 mg/L) compared to the initial inducer-free strain. CONCLUSIONS: In general, whereas the replacement of major cellulase genes leads to extreme decrease in the degradation capacity of cellulose, our inducer-free system enabled it and achieved high secretory production of POI with increased occupancy in glucose medium. This system would be a novel platform for heterologous recombinant protein production in T. reesei.


Assuntos
Celulase , Anticorpos de Domínio Único , Trichoderma , Celulase/genética , Celulase/metabolismo , Glucose/metabolismo , Anticorpos de Domínio Único/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Celulose/metabolismo , Trichoderma/metabolismo
6.
Sci Rep ; 13(1): 7827, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37188729

RESUMO

Fast-growing trees like Capirona, Bolaina, and Pashaco have the potential to reduce forest degradation because of their ecological features, the economic importance in the Amazon Forest, and an industry based on wood-polymer composites. Therefore, a practical method to discriminate specie (to avoid illegal logging) and determine chemical composition (tree breeding programs) is needed. This study aimed to validate a model for the classification of wood species and a universal model for the rapid determination of cellulose, hemicellulose, and lignin using FTIR spectroscopy coupled with chemometrics. Our results showed that PLS-DA models for the classification of wood species (0.84 ≤ R2 ≤ 0.91, 0.12 ≤ RMSEP ≤ 0.20, accuracy, specificity, and sensibility between 95.2 and 100%) were satisfied with the full spectra and the differentiation among these species based on IR peaks related to cellulose, lignin, and hemicellulose. Besides, the full spectra helped build a three-species universal PLS model to quantify the principal wood chemical components. Lignin (RPD = 2.27, [Formula: see text] = 0.84) and hemicellulose (RPD = 2.46, [Formula: see text] = 0.83) models showed a good prediction, while cellulose model (RPD = 3.43, [Formula: see text] = 0.91) classified as efficient. This study showed that FTIR-ATR, together with chemometrics, is a reliable method to discriminate wood species and to determine the wood chemical composition in juvenile trees of Pashaco, Capirona, and Bolaina.


Assuntos
Lignina , Madeira , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Lignina/análise , Madeira/química , Árvores , Melhoramento Vegetal , Celulose/análise , Análise Multivariada , Análise dos Mínimos Quadrados
7.
BMC Plant Biol ; 23(1): 259, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37189063

RESUMO

BACKGROUND: Human-guided crop domestication has lasted for more than 10,000 years. In terms of the domestication and breeding of vegetables, cellulose content in edible tissues is one of the most important traits. Primulina eburnea is a recently developed calcium-rich vegetable with a high soluble and bioavailable calcium content in its leaves. However, the high cellulose content in the leaves hampers the taste, and no research has been reported on the genetic basis of cellulose biosynthesis in this calcium-rich vegetable. RESULTS: We identified 36 cellulose biosynthesis-involved genes belonging to eight gene families in the P. eburnea genome. The cellulose accumulated decreasingly throughout leaf development. Nineteen genes were considered core genes in cellulose biosynthesis, which were highly expressed in buds but lowly expressed in mature leaves. In the nitrogen fertilization experiment, exogenous nitrogen decreased the cellulose content in the buds. The expressing pattern of 14 genes were consistent with phenotypic variation in the nitrogen fertilization experiment, and thus they were proposed as cellulose toolbox genes. CONCLUSIONS: The present study provides a strong basis for the subsequent functional research of cellulose biosynthesis-involved genes in P. eburnea, and provides a reference for breeding and/or engineering this calcium-rich vegetable with decreased leaf cellulose content to improve the taste.


Assuntos
Cálcio , Celulose , Humanos , Verduras , Melhoramento Vegetal , Nitrogênio
8.
Int J Hyperthermia ; 40(1): 2207797, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37196995

RESUMO

BACKGROUND: Phantoms accurately mimicking the electromagnetic and thermal properties of human tissues are essential for the development, characterization, and quality assurance (QA) of clinically used equipment for Hyperthermia Treatment (HT). Currently, a viable recipe for a fat equivalent phantom is not available, mainly due to challenges in the fabrication process and fast deterioration. MATERIALS AND METHODS: We propose to employ a glycerol-in-oil emulsion stabilized with ethylcellulose to develop a fat-mimicking material. The dielectric, rheological, and thermal properties of the phantom have been assessed by state-of-the-art measurement techniques. The full-size phantom was then verified in compliance with QA guidelines for superficial HT, both numerically and experimentally, considering the properties variability. RESULTS: Dielectric and thermal properties were proven equivalent to fat tissue, with an acceptable variability, in the 8 MHz to 1 GHz range. The rheology measurements highlighted enhanced mechanical stability over a large temperature range. Both numerical and experimental evaluations proved the suitability of the phantom for QA procedures. The impact of the dielectric property variations on the temperature distribution has been numerically proven to be limited (around 5%), even if higher for capacitive devices (up to 20%). CONCLUSIONS: The proposed fat-mimicking phantom is a good candidate for hyperthermia technology assessment processes, adequately representing both dielectric and thermal properties of the human fat tissue while maintaining structural stability even at elevated temperatures. However, further experimental investigations on capacitive heating devices are necessary to better assess the impact of the low electrical conductivity values on the thermal distribution.


Assuntos
Hipertermia Induzida , Humanos , Hipertermia Induzida/métodos , Imagens de Fantasmas , Temperatura , Celulose
9.
Chemosphere ; 331: 138813, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37127202

RESUMO

The detection and quantification of p-Nitrophenol in environmental samples are important for understanding the extent and impact of environmental pollution, protecting human health, ensuring regulatory compliance, and guiding remediation efforts. The main objective of this work was to investigate the electrochemical performance of a graphene oxide/cellulose nanofibril composite (GO/CNF) modified carbon paste electrode (GO/CNF/CPE) for the sensitive and reliable detection of p-nitrophenol in water samples. The transmission electron microscopy (TEM) technique was employed to enlighten the structure of nanocomposites. The electrochemical behavior of the fabricated electrochemical sensor was characterized via differential pulse voltammetry (DPV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS). Under optimized analytical conditions, the peak current of the analyte showed a wide linear relationship with its concentration in a range of 3.0 nM-210 µM with a low amount of the limit of detection (LOD) value of 0.8 nM determined by the DPV method. The proposed electrochemical sensor demonstrated excellent sensitivity, selectivity, and accuracy metrics in real sample analysis of p-nitrophenol.


Assuntos
Grafite , Poluentes da Água , Humanos , Celulose , Poluentes da Água/análise , Nitrofenóis/análise , Grafite/química , Eletrodos , Técnicas Eletroquímicas/métodos
10.
Infect Immun ; 91(5): e0013523, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37129526

RESUMO

Non-typhoidal Salmonella (NTS) serovars have a broad host range and cause gastroenteritis in humans. However, invasive NTS (iNTS) bloodstream infections have increased in the last decade, causing 60,000 deaths annually. Human-specific typhoidal Salmonella colonizes and forms biofilms on gallstones, resulting in chronic, asymptomatic infection. iNTS lineages are undergoing genomic reduction and may have adapted to person-to-person transmission via mutations in virulence, bile resistance, and biofilm formation. As such, we sought to determine the capacity of iNTS lineages for biofilm formation and the development of chronic infections in the gallbladder in our mouse model. Of the lineages tested (L1, L2, L3 and UK), only L2 and UK were defective for the rough, dry and red (RDAR) morphotype, correlating with the known bcsG (cellulose) mutation but not with csgD (curli) gene mutations. Biofilm-forming ability was assessed in vitro, which revealed a biofilm formation hierarchy of L3 > ST19 > UK > L1 = L2, which did not correlate directly with either the bcsG or the csgD mutation. By confocal microscopy, biofilms of L2 and UK had significantly less curli and cellulose, while L1 biofilms had significantly lower cellulose. All iNTS strains were able to colonize the mouse gallbladder, liver, and spleen in a similar manner, while L3 had a significantly higher bacterial load in the gallbladder and increased lethality. While there was iNTS lineage variability in biofilm formation, gallbladder colonization, and virulence in a chronic mouse model, all tested lineages were capable of colonization despite possessing biofilm-related mutations. Thus, iNTS strains may be unrecognized chronic pathogens in endemic settings.


Assuntos
Vesícula Biliar , Febre Tifoide , Camundongos , Animais , Humanos , Vesícula Biliar/microbiologia , Salmonella , Biofilmes , Celulose , Mutação
11.
ACS Appl Mater Interfaces ; 15(19): 23653-23661, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37155934

RESUMO

An energy-saving scheme that can simultaneously realize electromagnetic interference (EMI) shielding, passive solar radiative heating, and active Joule heating in a single wearable device is still a huge challenge. Here, by combining the unique properties of Ti3C2Tx MXene and biocompatible cellulose nanofibers (CNFs), a flexible, degradable, and antibacterial multifunctional Ti3C2Tx/CNF paper (∼0.6 Ω/sq) is constructed through a facile vacuum filtration strategy. The resultant device not only exhibits an admirable EMI shielding effectiveness of ∼48.5 dB at the X-band and a superior heating property including dual-driven electrothermal and photothermal conversion without energy but also possesses wide temperature range regulation and long-time stability. More impressively, both high antibacterial efficiency (toward both gram-positive and gram-negative bacteria) and good degradability with low-concentration hydrogen peroxide solution can also be achieved in Ti3C2Tx/CNF papers. This study provides a promising platform for practical applications of multifunctional Ti3C2Tx/CNFs in EMI shielding, thermotherapy, heat preservation, and antibacterial protection in harsh environments, satisfying the demands for energy-saving, environmentally friendly, and sustainable development.


Assuntos
Antibacterianos , Bactérias Gram-Negativas , Antibacterianos/farmacologia , Bactérias Gram-Positivas , Titânio , Celulose , Fenômenos Eletromagnéticos
12.
Carbohydr Res ; 528: 108812, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37126971

RESUMO

Cellulose succinates (CSs) having degrees of substitution (DSs) ranging from 0.78 to 2.77 were successfully obtained by reacting cellulose with succinic anhydride (SA) in dimethyl sulfoxide at room temperature using a small amount of inexpensive solid potassium carbonate as a catalyst. Interestingly, CSs with higher DS values were obtained with a much smaller amount of catalyst than previously reported. Moreover, it is possible to control the DS by tailoring the reaction time and mass ratio of cellulose/SA. The hydroxyl groups at the C-6, C-2, and C-3 positions were the main esterification positions. In this process, most of the raw materials are either incorporated into the product or are recoverable. The E-factor, which reflects the sustainability of a given process, was demonstrated to be reduced by 93% by recovering the raw materials.


Assuntos
Celulose , Anidridos Succínicos , Dimetil Sulfóxido , Succinatos
13.
Methods Mol Biol ; 2657: 53-77, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37149522

RESUMO

Cellulosomes are multi-enzymatic nanomachines that have been fine-tuned through evolution to efficiently deconstruct plant biomass. Integration of cellulosomal components occurs via highly ordered protein-protein interactions between the various enzyme-borne dockerin modules and the multiple copies of the cohesin modules located on the scaffoldin subunit. Recently, designer cellulosome technology was established to provide insights into the architectural role of catalytic (enzymatic) and structural (scaffoldin) cellulosomal constituents for the efficient degradation of plant cell wall polysaccharides. Owing to advances in genomics and proteomics, highly structured cellulosome complexes have recently been unraveled, and the information gained has inspired the development of designer-cellulosome technology to new levels of complex organization. These higher-order designer cellulosomes have in turn fostered our capacity to enhance the catalytic potential of artificial cellulolytic complexes. In this chapter, methods to produce and employ such intricate cellulosomal complexes are reported.


Assuntos
Celulose , Celulossomas , Celulose/metabolismo , Parede Celular/metabolismo , Membrana Celular/metabolismo , Genômica , Celulossomas/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Ciclo Celular/metabolismo
14.
Methods Mol Biol ; 2657: 27-51, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37149521

RESUMO

Lytic polysaccharide monooxygenases perform oxidative cleavage of glycosidic bonds in various polysaccharides. The majority of LMPOs studied so far possess activity on either cellulose or chitin and analysis of these activities is therefore the main focus of this review. Notably, however, the number of LPMOs that are active on other polysaccharides is increasing. The products generated by LPMOs from cellulose are either oxidized in the downstream end (at C1) or upstream end (at C4), or at both ends. These modifications only result in small structural changes, which makes both chromatographic separation and product identification by mass spectrometry challenging. The changes in physicochemical properties that are associated with oxidation need to be considered when choosing analytical approaches. C1 oxidation leads to a sugar that is no longer reducing but instead has an acidic functionality, whereas C4 oxidation leads to products that are inherently labile at high and low pH and that exist in a keto-gemdiol equilibrium that is strongly shifted towards the gemdiol in aqueous solutions. Partial degradation of C4-oxidized products leads to the formation of native products, which could explain why some authors claim to have observed glycoside hydrolase activity for LPMOs. Notably, apparent glycoside hydrolase activity may also be due to small amounts of contaminating glycoside hydrolases since these normally have much higher catalytic rates than LPMOs. The low catalytic turnover rates of LPMOs necessitate the use of sensitive product detection methods, which limits the analytical possibilities considerably. Modern liquid chromatography and mass spectrometry have become essential tools for evaluating LPMO activity and this chapter provides an overview of available methods together with a few novel tools. The methods described constitute a suite of techniques for analyzing oxidized carbohydrate products, which can be applied to LPMOs as well as other carbohydrate-active redox enzymes.


Assuntos
Oxigenases de Função Mista , Polissacarídeos , Oxigenases de Função Mista/metabolismo , Polissacarídeos/metabolismo , Cromatografia Líquida , Espectrometria de Massas , Oxirredução , Celulose/metabolismo , Glicosídeo Hidrolases/metabolismo
15.
Methods Mol Biol ; 2657: 103-114, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37149525

RESUMO

Microscale thermophoresis (MST) is an emerging technology for studying a broad range of biomolecular interactions with a high sensitivity. The affinity constant can be obtained for a wide range of molecules within minutes based on reactions in microliters. Here we describe the application of MST in quantifying protein-carbohydrate interactions. A CBM3a and a CBM4 are titrated with insoluble substrate (cellulose nanocrystal) and soluble oligosaccharide (xylohexaose), respectively.


Assuntos
Carboidratos , Celulose , Ligação Proteica
16.
J Mater Chem B ; 11(19): 4191-4202, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37128714

RESUMO

In this study, CNFs were provided by an efficient, unmodified, and clean biological method with enzymes and a small amount of alkali, compared to the CNCs with the chemical method involving a strong acid. To provide an accurate targeted selection for future applications, we made the following comparison by analyzing the differences in the preparation method, performance, and application performance of the two nanocelluloses. The result of this study indicated that CNFs and CNCs exhibited a crystallinity index of 58.2 and 83.5%, respectively. CNFs had a mean length (L) of 192.3 nm and a diameter (D) of 1.9 nm, and the average L and D of CNCs reached 123.6 nm and 3.7 nm, respectively. The solution viscosity of CNFs and CNCs reached 7.46 Pa s and 1.91 Pa s, respectively. CNFs and CNCs exhibited zeta potential values of -88.26 mV and -26.40 mV, respectively. The electrospun composite film of PLA-CNFs and PLA-CNCs achieved water contact angles of 138.7 and 34.5°, and the water-oil contact angle reached 24.7 and 30.5°, respectively. The breaking strength of PLA-CNFs and PLA-CNCs reached 96.07 cN and 163.23 cN, and the break elongation followed an order of PLA-CNCs (32.16%) < PLA-CNFs (34.70%). In brief, CNFs can make the composite membrane hydrophobic and with superior extension, and CNCs can make the composite membrane hydrophilic and enhance its strength. Both the composite films conformed to the non-toxic standard, and the PLA-CNFs film more significantly contributed to the cell growth, which is expected to serve as a medical material.


Assuntos
Cannabis , Nanopartículas , Celulose/química , Nanopartículas/química , Água , Poliésteres/química
17.
AAPS PharmSciTech ; 24(5): 113, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37127722

RESUMO

Microcrystalline cellulose (MCC) of different grades from different manufacturers differ in particulate and powder properties significantly. The choice of MCC is important to the development of a tablet formulation with satisfactory quality. In this study, the effects of five different MCCs (KG 802, Pharmacel 102, MC 302, M 200, and PH 112) that had different compactibility and tablet disintegration on the tablet quality of two different natural plant products (NPPs) were evaluated systematically, including Crataegi Folium ethanol extract (CF-E) and Sarcandrae Herba water extract (SH-W). The result of D-optimal mixture designs demonstrated that KG 802 showed the best ability to improve compression properties and tensile strength, followed by Pharmacel 102, MC 302, and M 200. PH 112 did the weakest. However, MCCs of different grades had no different influence on the disintegration of NPP tablets. Similar results were found in the experiments of the two different NPP powders, suggesting the generalization of the finding. Moreover, KG 802-containing CF-E formulations showed the largest optimum region size, that is, the lowest production risk. The design space sizes of SH-W were hardly sensitive to the change of MCCs, due to the better tabletability. In conclusion, the properties of MCCs could transfer to the high NPP loading (70%) formulations, leading to the variations on the compression properties and tablet quality. The poorer the tabletability of NPP, the more obvious the variation. The result is promising for the use of MCC and the manufacturing of high drug-loading NPP tablets by direct compression.


Assuntos
Celulose , Composição de Medicamentos/métodos , Celulose/química , Resistência à Tração , Comprimidos/química
18.
Rev Col Bras Cir ; 50: e20233536, 2023.
Artigo em Inglês, Português | MEDLINE | ID: mdl-37222383

RESUMO

Chronic ulcers of the lower limbs are common and recurrent, especially in the elderly population, they are disabling injuries that generate a great socioeconomic burden. This scenario encourages the development of new, low-cost therapeutic alternatives. The present study aims to describe the use of bacterial cellulose in the treatment of lower limb ulcers. This is an integrative literature review, carried out in the PubMed and Science Direct databases by associating the descriptors, with the inclusion criteria being clinical studies in the last 5 years, available in full in English, Portuguese and Spanish. Five clinical trials were analyzed and the main therapeutic effects obtained in the experimental groups that used bacterial cellulose dressings were a reduction in the area of the wounds, one of the studies showed a reduction of 44.18cm2 in the area of the wound, the initial lesions measured on average 89.46cm2 and at the end of the follow-up, they had an average of 45.28cm2, since the reduction in pain and the decrease in the number of exchanges were advantages described in all groups that used the BS. It is concluded that BC dressings are an alternative for the treatment of lower limb ulcers, their use also reduces operational costs related to the treatment of ulcers.


Assuntos
Úlcera da Perna , Úlcera , Idoso , Humanos , Extremidade Inferior , Materiais Biocompatíveis , Celulose
19.
Bioresour Technol ; 381: 129119, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37141998

RESUMO

Tetracycline (TC) and sugarcane bagasse had both exerted enormous strain on environmental security. In this work, new composite adsorbent designed by impregnating bio-waste bagasse with magnesium-aluminum layered double oxides (BC-MA) was innovatively brought forward for TC removal. Benefiting from the abundant adsorption sites supplied by developed pores structure (0.308 cm3·g-1), enlarged surface area (256.8 m2·g-1) and reinforced functional groups, the maximum adsorption amount of BC-MA for TC reached 250.6 mg g-1. Moreover, BC-MA displayed desirable adsorption capacity in diverse water environments coupled with excellent sustainable regeneration ability. The absorption process of TC by BC-MA was spontaneous and endothermic, and the pivotal rate-limiting stage pertained to intraparticle diffusion. The mechanisms proposed here mainly concerned π-π interactions, pore filling, complexation and hydrogen bonding. These findings suggested that the synthesis of modified biochar from bagasse would offer new opportunities for simultaneous waste resource reuse and water pollution control.


Assuntos
Saccharum , Poluentes Químicos da Água , Celulose , Água , Óxidos , Poluentes Químicos da Água/química , Cinética , Tetraciclina/química , Antibacterianos , Carvão Vegetal/química , Adsorção
20.
Bioresour Technol ; 381: 129132, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37149269

RESUMO

To excavate a complex co-degradation system for decomposing cellulose more efficiently, cellulose-degrading bacteria, including Bacillus subtilis WF-8, Bacillus licheniformis WF-11, Bacillus Cereus WS-1 and Streptomyces Nogalater WF-10 were added during maize straw and cattle manure aerobic composting. Bacillus and Streptomyces successfully colonized, which improve cellulose degrading ability. Continuous colonization of cellulose-degrading bacteria can promote the fungi to produce more precursors for humus and promote the negative correlation with Ascomycota. In the current study, the addition of cellulose-degrading bacteria has resulted in the rapid development of Mycothermus and Remersonia in the phylum Ascomycota as keystone fungal genera which constitute the foundation of the co-degradation system. Network analysis reveals the complex co-degradation system of efficient cellulose bacteria and mature fungi to treat cellulose in the process of straw aerobic composting mainly related to the influence of total carbon (TC) /total nitrogen (TN) and humic acid (HA)/fulvic acid (FA). This research offers a complex co-degradation system more efficiently to decompose cellulose aiming to maintain the long-term sustainability of agriculture.


Assuntos
Celulose , Compostagem , Animais , Bovinos , Celulose/metabolismo , Agricultura , Solo , Bacillus subtilis/metabolismo , Esterco/microbiologia
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