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Solid lipid nanoparticles (SLN) based on candelilla wax were prepared using the hot homogenization technique. The resulting suspension had monomodal behavior with a particle size of 809-885 nm; polydispersity index < 0.31, and zeta potential of -3.5 mV 5 weeks after monitoring. The films were prepared with SLN concentrations of 20 and 60 g/L, each with a plasticizer concentration of 10 and 30 g/L; the polysaccharide stabilizers used were either xanthan gum (XG) or carboxymethyl cellulose (CMC) at 3 g/L. The effects of temperature, film composition, and relative humidity on the microstructural, thermal, mechanical, and optical properties, as well as the water vapor barrier, were evaluated. Higher amounts of SLN and plasticizer gave the films greater strength and flexibility due to the influence of temperature and relative humidity. The water vapor permeability (WVP) was lower when 60 g/L of SLN was added to the films. The arrangement of the SLN in the polymeric networks showed changes in the distribution as a function of the concentrations of the SLN and plasticizer. The total color difference (ΔE) was greater when the content of the SLN was increased, with values of 3.34-7.93. Thermal analysis showed an increase in the melting temperature when a higher SLN content was used, whereas a higher plasticizer content reduced it. Edible films with the most appropriate physical properties for the packaging, shelf-life extension, and improved quality conservation of fresh foods were those made with 20 g/L of SLN, 30 g/L of glycerol, and 3 g/L of XG.

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The burden of chronic wounds is growing due to the increasing incidence of trauma, aging, and diabetes, resulting in therapeutic problems and increased medical costs. Thus, this study reports the synthesis and comprehensive characterization of water-responsive hybrid hydrogels based on carboxymethyl cellulose (CMC) and poly(vinyl alcohol) (PVA) using citric acid (CA) as the chemical crosslinking agent, with tunable physicochemical properties suitable to be applied as a wound dressing for soft tissue engineering applications. They were produced through an eco-friendly process under mild conditions. The hydrogels were designed and produced with flexible swelling degree properties through the selection of CMC molecular mass (Mw = 250 and 700 kDa) and degree of functionalization (DS = 0.81), degree of hydrolysis of PVA (DH > 99%, Mw = 84-150 kDa) associated with synthesis parameters, CMC/PVA ratio and extension of chemical crosslinking (CA/CMC:PVA ratio), for building engineered hybrid networks. The results demonstrated that highly absorbent hydrogels were produced with swelling degrees ranging from 100% to 5000%, and gel fraction from 40% to 80%, which significantly depended on the concentration of CA crosslinker and the presence of PVA as the CMC-based network modifier. The characterizations indicated that the crosslinking mechanism was mostly associated with the chemical reaction of CA carboxylic groups with hydroxyl groups of CMC and PVA polymers forming ester bonds, rendering a hybrid polymeric network. These hybrid hydrogels also presented hydrophilicity, permeability, and structural features dependent on the degree of crosslinking and composition. The hydrogels were cytocompatible with in vitro cell viability responses of over 90% towards model cell lines. Hence, it is envisioned that this research provides a simple strategy for producing biocompatible hydrogels with tailored properties as wound dressings for assisting chronic wound healing and skin tissue engineering applications.

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Diabetic foot ulcers (DFUs) are considered one of the most severe chronic complications of diabetes and can lead to amputation in severe cases. In addition, bacterial infections in diabetic chronic wounds aggravate this scenario by threatening human health. Wound dressings made of polymer matrices with embedded metal nanoparticles can inhibit microorganism growth and promote wound healing, although the current clinical treatments for diabetic chronic wounds remain unsatisfactory. In this view, this research reports the synthesis and characterization of innovative hybrid hydrogels made of carboxymethyl cellulose (CMC) and poly(vinyl alcohol) (PVA) chemically crosslinked by citric acid (CA) functionalized with silver nanoparticles (AgNPs) generated in situ using an eco-friendly aqueous process. The results assessed through comprehensive in vitro and in vivo assays demonstrated that these hybrid polymer hydrogels functionalized with AgNPs possess physicochemical properties, cytocompatibility, hemocompatibility, bioadhesion, antibacterial activity, and biocompatibility suitable for wound dressings to support chronic wound healing process as well as preventing and treating bacterial infections. Hence, it can be envisioned that, with further research and development, these polymer-based hybrid nanoplatforms hold great potential as an important tool for creating a new generation of smart dressings for treating chronic diabetic wounds and opportunistic bacterial infections.

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Chitosan (CHI) and carboxymethyl cellulose (CMC) are naturally sourced materials with excellent physical, chemical, and biological properties, which make them a promising tool for the development of different medical devices. In this research, CHI-CMC wound dressings were manufactured, by using different colloidal suspensions of silver nanoparticles (AgNPs) synthesized from the ligninolytic fungus Anamorphous Bjerkandera sp. R1, called CS and SN. Transmission electron microscopy (TEM), UV-Vis spectroscopy, and dynamic light scattering (DLS) analysis were used to characterize AgNPs. The wound dressings were characterized, by scanning electron microscopy (SEM), optical microscopy and their mechanical, antimicrobial, and biological properties were evaluated. The results of the different characterizations revealed the formation of spherical AgNPs with a mean size between 10 and 70 nm for the different mixtures worked. The mechanical properties of CHI-CMS-AgNPs doped with CS and SN suspensions showed superior mechanical properties with respect to CHI-CMC wound dressings. Compared to the latter, CHI-CMC-AgNPs wound dressings yielded better antibacterial activity against the pathogen Escherichia coli. In biological assays, it was observed that manufactured CHI-CMC-AgNPs wound dressings were not toxic when in contact with human skin fibroblasts (Detroit). This study, then, suggests that this type of wound dressings with a chitosan matrix and carboxymethyl cellulose doped with biologically synthesized nanoparticles from the fungus Bjerkandera sp., may be an ideal alternative for the manufacture of new wound dressings.

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This study proposes the use of green matrices of cellulose nanocrystals (CNC) and a nanocomposite of CNC with carboxymethyl cellulose (CMC) for efficiently encapsulating the plant biocontrol agent Trichoderma harzianum. Beads containing spores of the microorganism were produced by dripping dispersions of the polymers into a CaCl2 coagulation bath, resulting in the crosslinking of CNC chains by Ca2+ ions. SEM micrographs evidenced the T. harzianum spores in the encapsulation matrices. X-ray microtomography confirmed the random distribution of the microorganism within the polymeric matrix and the presence of internal pores in the CNC:CMC:spores beads. Encapsulation in the CNC:CMC nanocomposite favored growth of the fungus after 10 days of storage at room temperature, which could be attributed to the presence of internal pores and to the extra carbon source provided by the CMC. The results indicated that CNC:CMC nanocomposites are promising materials for protecting and delivering microbial inoculants for agricultural applications.

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Intensive research on biodegradable films based on natural raw materials such as carboxymethyl cellulose (CMC) has been performed because it enables the production of transparent films with suitable barrier properties against oxygen and fats. Considering the importance of the production of this type of film at the industrial level, a scalable and continuous drying method is required. Refractance window-conductive hydro drying (RW-CHD) is a sustainable and energy-efficient method with high potential in drying this kind of compound. The objective of this study was to evaluate the factors (CMC thickness, heating water temperature, and film type) and radiation penetration depth that affect drying time and energy consumption. It was found that drying time decreased with increasing temperature and decreasing thickness. Similarly, energy consumption decreased with decreasing temperature and thickness. However, the drying time and energy consumed per unit weight of product obtained were equivalent when drying at any of the thicknesses evaluated. Film type had little effect on time and energy consumption compared to the effects of temperature and CMC thickness. The radiation penetration depth into the CMC was determined to be 1.20 ± 0.19 mm. When the thickness was close to this value, the radiation energy was better utilized, which was reflected in a higher heating rate at the beginning of drying.

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OBJECTIVE: To evaluate the antimicrobial activity of a silver nanoparticles/carboxymethyl-cellulose (AgNPs/CMC) composite on in vitro and dentine disc heterogeneous biofilms. DESIGN: AgNPs/CMC composite effect on normal human gingival fibroblast cells (HGF) viability was determined by the MTT reduction assay. In addition, we evaluated the antimicrobial effect of AgNPs/CMC composite on Candida albicans, Enterococcus faecalis, and Fusobacterium nucleatum growth in vitro and heterogeneous biofilms, as well as dentine disc biofilms. RESULTS: Quasi-spherical AgNPs/CMC composites, with a mean 22.3 nm particle-size were synthesized. They were not toxic to HGF cells at concentrations tested that were antimicrobial, however they caused significant cytotoxicity (89 %, p <  0.05) at concentrations > 15 µg/mL. In vitro, they inhibited up to 67 %, 66 %, and 96 % C. albicans, E. faecalis, and F. nucleatum growth at concentrations ranging from 1.2 µg/mL to 9.6 µg/mL, as compared with untreated control. We also demonstrated significant (p <  0.05) 58 % biofilm reduction by 4.8 µg/mL AgNPs/CMC composite on human dentine discs. CONCLUSION: AgNPs/CMC composite showed anti biofilm activity on monocultures, heterogenous cultures, and dentine discs, resulting a potentially effective alternative to prevent and eliminate infections after endodontic treatment.

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In this paper we report on the influence of polysaccharides' molecular structure on the antibacterial activity and cytotoxicity of composites based on silver nanoparticles (AgNPs) immobilized into carboxymethyl-cellulose (CMC). These composites were green synthesized from the reduction of silver ions into aqueous solutions of the polysaccharide, using CMC with different degree of substitution (DS) and molecular weight (Mw). The composites were characterized by transmission electron microscopy (TEM), as well as infrared (ATR-FTIR), ultraviolet (UV-Vis), Raman, and X-ray photo-electron (XPS) spectroscopic techniques. The antibacterial activity was evaluated with minimum inhibitory concentration against Enterococcus faecalis. The cytotoxicity of composites was assessed against human gingival fibroblast. Experimental evidence suggests that particle size distribution and morphology of AgNPs change according to the quantity of silver precursor added to the reaction, as well as the DS and Mw of CMC used for composites preparation. This is related to the dispersion of silver precursor into aqueous solutions of the polysaccharide and the formation of Ag-O coordination bonds among AgNPs and COO- moieties of CMC. Moreover, these coordination bonds modify the ability of nanoparticles to produce and release Ag+ into aqueous dispersion, adjusting their antibacterial activity and the induction of cytotoxicity into the tested biological environments.

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Thirty-seven different colonies were isolated from decomposing logs of textile industries. From among these, a thermotolerant, gram-positive, filamentous soil bacteria Streptomyces durhamensis vs15 was selected and screened for cellulase production. The strain showed clear zone formation on the CMC agar plate after Gram's iodine staining. Streptomyces durhamensis vs15 was further confirmed for cellulase production by estimating the reducing sugars through the dinitrosalicylic acid (DNS) method. The activity was enhanced by sequential mutagenesis using three mutagens of ultraviolet irradiation (UV), N methyl-N'-nitro-N-nitrosoguanidine (NTG), and Ethyl methanesulfonate (EMS). After mutagenesis, the cellulase activity of GC23 (mutant) was improved to 1.86-fold compared to the wild strain (vs15). Optimal conditions for the production of cellulase by the GC 23 strain were evaluated using Response Surface Methodology (RSM) and Artificial Neural Network (ANN). The effects of pH, temperature, duration of incubation, and substrate concentration on cellulase production were evaluated. Optimal conditions for the production of cellulase enzyme using Carboxymethyl cellulose as a substrate are 55 ºC of temperature, pH of 5.0, and incubation for 40 h. The cellulase activity of the mutant Streptomyces durhamensis GC23 was further optimized to 2-fold of the activity of the wild type by RSM and ANN

Trinta e sete colônias diferentes foram isoladas de toras em decomposição das indústrias têxteis. Dentre estes, uma bactéria do solo filamentosa termotolerante, Gram-positiva, Streptomyces durhamensis vs15, foi selecionada e rastreada quanto à produção de celulase. A cepa mostrou uma formação de zona clara na placa de ágar CMC após a coloração com iodo Gram. Streptomyces durhamensis vs15 foi ainda confirmado para a produção de celulase, estimando os açúcares redutores pelo método do ácido dinitrosalicílico (DNS). A atividade foi aprimorada por mutagênese sequencial usando três mutagênicos de irradiação ultravioleta (UV), N metil-N'-nitro-N-nitrosoguanidina (NTG) e metanossulfonato de etil (EMS). Após a mutagênese, a atividade celulase do GC23 (mutante) foi melhorada para 1,86 vezes em comparação com a cepa selvagem (vs15). As condições ideais para a produção de celulase pela cepa GC 23 foram avaliadas usando a Metodologia de Superfície de Resposta (RSM) e a Rede Neural Artificial (RNA). Os efeitos do pH, temperatura, duração da incubação e concentração de substrato na produção de celulase foram avaliados. As condições ideais para a produção da enzima celulase usando Carboximetilcelulose como substrato são 55 ° C de temperatura, pH de 5,0 e incubação por 40 h. A atividade da celulase do mutante Streptomyces durhamensis GC23 foi ainda otimizada para 2 vezes a atividade do tipo selvagem por RSM e RNA.

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Biomimetic nanoparticles are hybrid nanostructures in which the uppermost layer is similar to a cell membrane. In these nanoparticles, lipids and biopolymers can be organized to improve drug incorporation and delivery. This report provides instructions for the preparation and physical characterization of four different biomimetic nanoparticles: (1) polystyrene sulphate (PSS) nanoparticles covered with one cationic dioctadecyl dimethylammonium bromide bilayer (DODAB), which incorporates dimeric channels of the antimicrobial peptide Gramicidin D; (2) silica nanoparticles covered with one single bilayer of the antimicrobial cationic lipid DODAB; (3) hybrid lipid/polymer indomethacin (IND) nanoparticles from injection of IND/DODAB ethanolic solution in a water solution of carboxymethyl cellulose (CMC); (4) bactericidal and fungicidal nanoparticles from DODAB bilayer fragments (BF) covered consecutively by a CMC and a poly(diallyl dimethyl ammonium chloride) (PDDA) layer. These examples provide the basis for the preparation and characterization of novel biomimetic nanoparticles with lipids and/or biopolymers in their composition. The polymers and lipids in the hybrid nanoparticle composition may impart stability and/or bioactivity and/or provide adequate microenvironments for carrying bioactive drugs and biomolecules.

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Carboxymethyl cellulose (CMC)-based films were developed by incorporating green coffee oil (GCO) obtained by cold pressing and hydroalcoholic extracts of its residues. The effect of cake (CE) and sediment extracts (SE) in different proportions (20-40%) and GCO on chemical, morphological, physical, mechanical, optical, and antioxidant properties of the films was investigated. Eight fatty acids and four major phenolic compounds were identified by High-Resolution Direct-Infusion Mass Spectrometry in GCO and residue extracts. FTIR indicated interactions among CMC, phenolic compounds, and fatty acids. Films enriched with residue extracts presented heterogeneous microstructure. The tensile strength of the films decreased from 58 to 3 MPa with the extracts concentration, while elongation increased from 28 to 156% (p < 0.05). The water vapor permeability (averaging 3.94 × 10-8 g mm/cm2 h Pa) was not significantly affected by the extracts and GCO. The surface color was influenced by the type and concentration of extracts (p < 0.05), the film with SE40% had remarkable UV-vis barrier properties. The incorporation of GCO residue extracts imparted high antioxidant capacity to the CMC-based films, especially with CE40% (643.8 µmol Trolox eq./g dried film; 51.3 mg GAE/g dried film). General observations indicated the potential of these films, mainly the ones containing CE, like active packaging material for food applications.

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Novel core-shell superparamagnetic nanofluids composed of magnetic iron oxide (Fe3O4, MION) and cobalt-doped (CoxFe3-xO4, Co-MION) nanoparticles functionalized with carboxymethyl cellulose (CMC) ligands were designed and produced via green colloidal aqueous process. The effect of the degree of substitution (DS = 0.7 and 1.2) and molecular mass (Mw) of CMC and cobalt doping concentration on the physicochemical and magnetic properties of these nanoconjugates were comprehensively investigated using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction, transmission electron microscopy (TEM) with selected area electron diffraction, X-ray fluorescence, dynamic light scattering (DLS), zeta potential (ZP) analysis, vibrating sample magnetometry (VSM) and electron paramagnetic resonance spectroscopy (EPR). The results demonstrated the effect of concentration of carboxylate groups and Mw of CMC on the hydrodynamic dimension, zeta potential, and generated heat by magnetic hyperthermia of MION nanoconjugates. Co-doping of MION showed significant alteration of the electrostatic balance of charges of the nanoconjugates interpreted as effect of surface interactions. Moreover, the VSM and EPR results proved the superparamagnetic properties of these nanocolloids, which were affected by the presence of CMC and Co-doping of iron oxide nanoparticles. These magnetic nanohybrids behaved as nanoheaters for killing brain cancer cells in vitro with prospective future applications in oncology and nanomedicine.

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The combination of bismuth(III) citrate and the antibiotic furazolidone (FDZ) results in a synergetic effect on Helicobacter pylori eradication. However, the problems associated with their oral administration are challenges to overcome. Thus, in the present study, sodium alginate (SA)/carboxymethyl cellulose (CMC) blend hydrogels (SC) were developed for concomitant and controlled release of furazolidone and bismuth(III). The blank formulation (SCblank) and the three drug-loaded hydrogels (SCFDZ, SCBi, and SCFDZ-Bi) were prepared by casting method and characterized by infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, and X ray powder diffraction analyses. The swelling equilibrium and cumulative release amounts of FDZ and Bi3+ have indicated distinct behaviors of the hydrogels to different pH values. The bismuth-containing sample (SCFDZ-Bi) presents more resistance to degradation on a neutral solution and shows more suitable properties for controlled drug release than the sample without bismuth (SCFDZ). Microbiological studies, using Escherichia coli as a model, show bacteria viability reduction in presence of the drug-loaded samples. The developed system containing furazolidone and bismuth(III) appears to be promising for oral administration with concomitant and controlled release of these drugs aimed at the pharmacological treatment of gastrointestinal disorders.

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In this paper, the synthesis of magnetic nanofibrous materials with a soft ferromagnetic response based on magnetite nanoparticles (SMON) loaded to aqueous carboxymethyl-cellulose (CMC)/polyvinyl-alcohol (PVA) polymeric blends is reported. The nanofibrous materials were obtained from the electrospinning of SMON-CMC/PVA blends with different SMON content, applying a constant tension of 15 kV. The synthesized samples were analyzed by transmission electron microscopy, scanning electron microscopy, attenuated total reflectance Fourier transform infrared, Raman and X-Ray photoelectron spectroscopy, as well as static magnetic measuring. Our experimental findings indicate that nanofibers' diameter decreases as SMON content in the electrospun polymeric blends is increased, since these magnetic nanoparticles diminish the interactions between PVA and CMC molecules, which improves their spinnability. Moreover, the spatial distribution of SMON in the fibers provides to the synthesized nanofibrous materials a novel soft ferromagnetic response at room temperature. This phenomenon is attributed to the formation of nanoparticles' aggregates that are discretely distributed in the nanofibers.

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Municipal waste is rich in lignocellulosic compounds which contain cellulose, lignin and hemicellulose. Microorganisms can break down such compounds and convert them into glucose and other carbohydrates. The current study was performed to isolate and identify cellulolytic bacteria in municipal waste. Municipal waste samples were collected and plated on Carboxymethyl cellulose (CMC) agar. Preliminary identification of the isolates was performed using standard biochemical assays. The activity of carboxymethyl cellulose (CMCase) was specified through measuring the release of reducing sugars from CMC. Different nitrogen sources at various concentrations and initial pH values were evaluated for their effect on enzyme production. Further the enzyme production was determined at different fermentation times. Molecular identification was then performed using bacterial 16s rRNA gene amplification and sequencing. A cellulolytic bacterium was isolated from municipal waste samples and identified based on morphological, physiological and biochemical characteristics along with 16S rRNA analysis. The isolated bacterium was identified as Bacillus subtilis (accession number: KU681044). Whose growth characteristics showed that its growth curve entered the logarithmic phase following 10­18 h with the stable growth phase ranging from 23 to 37 h. The optimal carbon source for fermentation was 1% rice hull, with the nitrogen source comprised of 2% peptone and yeast extract. The the minimum CMCase activity was observed at an initial medium pH of 4.0, while the maximum was observed at pH 7. The strain grew vigorously and the cellulase yield was high at 6­24 h fermentation time period. The isolated bacteria showed the degrading potential of cellulose which could be employed in local industrial process.

Resíduos urbanos são ricos em compostos lignocelulósicos que contêm celulose, lignina e hemicelulose. Microrganismos podem quebrar esses compostos e convertê-los em glicose e outros carboidratos. O presente estudo foi realizado para isolar e identificar bactérias celulolíticas em resíduos urbanos. Amostras de resíduos municipais foram coletadas e plaqueadas em ágar Carboximetilcelulose (CMC). A identificação preliminar dos isolados foi realizada utilizando ensaios bioquímicos padrão. A atividade da carboximetilcelulose (CMCase) foi especificada através da medição da liberação de açúcares redutores da CMC. Diferentes fontes de nitrogênio em várias concentrações e valores iniciais de pH foram avaliados quanto ao seu efeito na produção de enzimas. Além disso, a produção de enzima foi determinada em diferentes tempos de fermentação. A identificação molecular foi então realizada utilizando amplificação e sequenciamento do gene bacteriano 16s rRNA. Uma bactéria celulolítica foi isolada de amostras de resíduos urbanos e identificada com base em características morfológicas, fisiológicas e bioquímicas, juntamente com a análise 16S rRNA. A bactéria isolada foi identificada como Bacillus subtilis (número de acesso: KU681044). Cujas características de crescimento mostraram que sua curva de crescimento entrou na fase logarítmica após 10-18 h com a fase de crescimento estável variando de 23 a 37 h. A fonte de carbono ótima para a fermentação foi 1% de casca de arroz, com a fonte de nitrogênio composta de 2% de peptona e extrato de levedura. A atividade mínima de CMCase foi observada em um pH médio inicial de 4,0, enquanto a máxima foi observada em pH 7. A linhagem cresceu vigorosamente e o rendimento de celulase foi alto no período de 6 a 24 horas de fermentação. As bactérias isoladas mostraram o potencial de degradação da celulose que poderia ser empregada no processo industrial local.

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This study focused on the synthesis and comprehensive characterization of environmentally friendly hydrogel membranes based on carboxymethyl cellulose (CMC) for wound dressing and skin repair substitutes. These new CMC hydrogels were prepared with two degrees of functionalization (DS=0.77 and 1.22) and chemically crosslinked with citric acid (CA) for tuning their properties. Additionally, CMC-based hybrids were prepared by blending with polyethylene glycol (PEG, 10wt.%). The results demonstrated that superabsorbent hydrogels (SAP) were produced with swelling degree typically ranging from 100% to 5000%, which was significantly dependent on the concentration of CA crosslinker and the addition of PEG as network modifier. The spectroscopical characterizations indicated that the mechanism of CA crosslinking was mostly associated with the chemical reaction with CMC hydroxyl groups and that PEG played an important role on the formation of a hybrid polymeric network. These hydrogels presented very distinct morphological features depended on the degree of crosslinking and the surface nanomechanical properties (e.g., elastic moduli) were drastically affected (from approximately 0.08GPa to 2.0GPa) due to the formation of CMC-PEG hybrid nanostructures. These CMC-based hydrogels were cytocompatible considering the in vitro cell viability responses of over 95% towards human embryonic kidney cells (HEK293T) used as model cell line.

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Background: Endoglucanase plays a major role in initiating cellulose hydrolysis. Various wild-type strains were searched to produce this enzyme, but mostly low extracellular enzyme activities were obtained. To improve extracellular enzyme production for potential industrial applications, the endoglucanase gene of Bacillus subtilis M015, isolated from Thai higher termite, was expressed in a periplasmic-leaky Escherichia coli. Then, the crude recombinant endoglucanase (EglS) along with a commercial cellulase (Cel) was used for hydrolyzing celluloses and microbial hydrolysis using whole bacterial cells. Results: E. coli Glu5 expressing endoglucanase at high levels was successfully constructed. It produced EglS (55 kDa) with extracellular activity of 18.56 U/mg total protein at optimal hydrolytic conditions (pH 4.8 and 50°C). EglS was highly stable (over 80% activity retained) at 40­50°C after 100 h. The addition of EglS significantly improved the initial sugar production rates of Cel on the hydrolysis of carboxymethyl cellulose (CMC), microcrystalline cellulose, and corncob about 5.2-, 1.7-, and 4.0-folds, respectively, compared to those with Cel alone. E. coli Glu5 could secrete EglS with high activity in the presence of glucose (1% w/v) and Tween 80 (5% w/v) with low glucose consumption. Microbial hydrolysis of CMC using E. coli Glu5 yielded 26 mg reducing sugar/g CMC at pH 7.0 and 37°C after 48 h. Conclusions: The recombinant endoglucanase activity improved by 17 times compared with that of the native strain and could greatly enhance the enzymatic hydrolysis of all studied celluloses when combined with a commercial cellulase.

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In this study, it is reported the use of sodium carboxymethyl cellulose (CMCel) as a multifunctional biocompatible polysaccharide for the direct synthesis of fluorescent alloyed-ZnCdS quantum dot (QD) nanoconjugates via aqueous "green" process at room temperature. The nanoconjugates were extensively characterized by spectroscopical (NMR, FTIR, UV-vis, PL) and morphological techniques (DLS, TEM) for accessing their structural and physicochemical properties associated with X-ray photoelectron spectroscopy (XPS) for surface and interface analysis. The results proved the hypothesis of formation of core-shell nanostructures composed by the semiconductor ZnCdS QD core and the organic biocompatible ligand CMCel shell. Moreover, CMCel chemical functional groups played a pivotal role for controlling the size of water-soluble colloidal nanocrystals (2r=4-5nm) and hydrodynamic diameters (<15nm) evidenced by metal complexation and interactions at the nanointerfaces. Additionally, these nanoconjugates were cytocompatible and luminescent for bioimaging human osteosarcoma cancer cells. Thus, these novel polysaccharide-based fluorescent bioconjugates offer promising perspectives as nanoplatforms for cancer cell bioimaging and diagnosis purposes.

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In this contribution a novel green chemistry approach for the synthesis of nanofibrous materials based on blends of carboxymethyl-cellulose (CMC)-silver nanoparticles (AgNPs) composite and polyvinyl-alcohol (PVA) is proposed. These nanofibrous materials were obtained from the electrospinning of blends of aqueous solutions of CMC-AgNPs composite and PVA, which were prepared at different CMC/PVA weight ratios in order to electrospin nanofibers applying a constant tension of 15kV. The synthesized materials were characterized by means of transmission electron microscopy, scanning electron microscopy; as well as Fourier-transform infrared, ultraviolet and Raman spectroscopic techniques. Experimental evidence suggests that the diameter of the nanofibers is thinner than any other reported in the literature regarding the electrospinning of CMC. This feature is related to the interactions of AgNPs with carboxyl functional groups of the CMC, which diminish those between the later and acetyl groups of PVA.

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We aimed to evaluate the effects of the barrier agent sodium carboxymethyl cellulose (SCMC) with and without dexamethasone for the prevention of postoperative adhesion formation in a rat model of postoperative peritoneal adhesion. A total of 160 three-month old male and female Wistar rats underwent a laparotomy, and adhesions were induced by ileocecal abrasion. Rats were randomly assigned to 4 groups (n=40 each): group A, untreated; group B, treated with SCMC only; group C1, treated with SCMC + 3 mg dexamethasone, and group C2, treated with SCMC + 8 mg dexamethasone. After 12 days, adhesion formation and histopathological changes were compared. In groups A, B, C1, and C2, the mortality rates were 10, 5, 5, and 5%, respectively. In groups C1 and C2, the adhesions were filmy and easy to dissect and were milder compared with those in groups A and B. The total adhesion score in group C1 (3.38±0.49) was significantly lower than that of group B (6.01±0.57; P<0.01) or group A (8.01±0.67; P<0.05). There was no significant difference in adhesion formation between groups C1 and C2. Compared with groups A and B, groups C1 and C2 exhibited milder histopathological changes. SCMC in combination with dexamethasone can prevent adhesion formation and is a better barrier agent than SCMC alone. The safety and feasibility of SCMC in combination with dexamethasone to prevent adhesion formation after abdominal surgery warrants further clinical study.

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