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Calcium tartrate instability in wines has been a neglected topic for many years. However, it seems that this problem is gaining prominence, and the industry welcomes inputs to address this issue. Among the alternatives that winemakers use for tartrate salt stabilization, the addition of authorized protective colloids is one of the best choices because they are easy to apply and have a low energetic cost. In the present study, the same red wine was treated with five different commercially available protective colloids in triplicate. The effectiveness of such colloids on calcium tartrate potential instability was estimated, in addition to their side effects on the phenolic composition of the treated wines and their astringency perception, as assessed by sensory analyses of the treated wine. The results show that, under these trial conditions, carboxymethylcellulose is the best choice for reducing the risk of calcium tartrate precipitation in wine. Moreover, the application of protective colloids to the wines had little effect on their color, phenolic composition, or evolution during one year of bottle storage. Finally, the addition of protective colloids did not impact the astringency intensity, but it influenced the dynamic perception of astringency according to the temporal dominance of sensation analysis.
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Aedes mosquito-borne diseases remain a significant global health threat, necessitating effective control strategies. This study introduces monoterpenes-based nanohydrogels for potential use as repellents against Aedes aegypti, the primary dengue vector worldwide. We formulated hydrogels using cymene- and myrcene-based nanoemulsions with different polymers: chitosan, carboxymethylcellulose (CMC), and carbopol®. Our evaluations of rheological, texture, and bioadhesive properties identified CMC hydrogel as the most promising gelling agent for topical application, exhibiting sustained monoterpene release over 12 h with low skin permeation and high retention in the stratum corneum. Myrcene-loaded CMC hydrogel achieved a 57% feeding deterrence compared to 47% with cymene hydrogel in the mosquito membrane-feeding model. Molecular docking studies revealed interactions between myrcene and an essential amino acid (Ile116) in the Ae. aegypti odorant-binding protein 22 (AeOBP22), corroborating its higher repellent efficacy. These findings suggest that myrcene-loaded CMC hydrogels offer a promising, minimally invasive strategy for personal protection against Ae. aegypti and warrant further investigation to optimize monoterpene concentrations for vector control.
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BACKGROUND: Folic acid (FA), a synthetically produced compound analogous to vitamin B9, also referred to as vitamin folate, is an essential compound in human health and faces challenges in stability during food processing. This study explores the incorporation of FA into carboxymethylcellulose (CMC) nanofibers using electrospinning to enhance its stability. RESULTS: In this study, optimization of both electrospinning and solution parameters facilitated the fabrication of nanofibers. Furthermore, incorporating FA into CMC/polyethylene oxide (PEO) nanofibers resulted in thinner fibers, with an average diameter of 88 nm, characterized by a flat shape and smooth surface. Fourier transform infrared spectroscopic analysis demonstrated substantial hydrogen bonding interactions between FA and the polar groups present in CMC. This interaction contributed to an encapsulation efficiency of 94.5%, with a yield exceeding 87%. Thermal analysis highlighted mutual interference between CMC and PEO, with FA enhancing the thermal stability and reducing the melting temperatures and enthalpies of PEO, while also increasing the reaction heats of CMC. The encapsulated FA remained stable in acidic conditions, with only 6% degradation over 30 days, demonstrating the efficacy of CMC/PEO nanofibers in safeguarding FA against acidic environments. Moreover, the nanofibers provided a protective barrier against UV radiation, thereby preserving the stability of FA. CONCLUSION: This study emphasizes the efficacy of CMC/PEO nanofibers as a protective matrix against FA degradation. The findings indicate that this innovative approach could significantly diversify the applications of FA in food fortification, addressing concerns regarding its vulnerability to temperature and hydrolysis reactions during food processing. © 2024 Society of Chemical Industry.
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Carboximetilcelulose Sódica , Ácido Fólico , Nanofibras , Polietilenoglicóis , Nanofibras/química , Ácido Fólico/química , Carboximetilcelulose Sódica/química , Polietilenoglicóis/química , Estabilidade de Medicamentos , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Composição de Medicamentos/métodosRESUMO
Erythrosine displays potential photodynamic activity against microorganisms and unhealthy cells. However, erythrosine has high hydrophilicity, negatively impacting on permeation through biological membranes. Combining biological macromolecules and thermoresponsive polymers may overcome these erythrosine-related issues, enhancing retention of topically applied drugs. The aim of this work was to investigate the performance of adhesive and thermoresponsive micellar polymeric systems, containing erythrosine in neutral (ERI) or disodium salt (ERIs) states. Optimized combinations of poloxamer 407 (polox407) and sodium carboxymethylcellulose (NaCMC) or hydroxypropyl methylcellulose (HPMC) were used as platforms for ERI/ERIs delivery. The rheological and mechanical properties of the systems was explored. Most of the formulations were plastic, thixotropic and viscoelastic at 37 °C, with suitable gelation temperature for in situ gelation. Mechanical parameters were reduced in the presence of the photosensitizer, improving the softness index. Bioadhesion was efficient for all hydrogels, with improved parameters for mucosa in contrast to skin. Formulations composed of 17.5 % polox407 and 3 % HPMC or 1 % NaCMC with 1 % (w/w) ERI/ERIs could release the photosensitizer, reaching different layers of the skin/mucosa, ensuring enough production of cytotoxic species for photodynamic therapy. Functional micelles could boost the photodynamic activity of ERI and ERIs, improving their delivery and contact time with the cells.
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Adesivos , Celulose , Eritrosina/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Poloxâmero , Polímeros , Derivados da HipromeloseRESUMO
Fats play multiple roles in determining the desirable characteristics of foods. However, there are health concerns about saturated and trans fats. Bigels have been proposed as a novel fat replacer in foods. This research evaluated the role of the type of hydrogel in the development of bigels to be used as fat replacers in cookies. Bigels were made with beeswax/canola oil oleogel and sodium alginate and carboxymethylcellulose hydrogels. The results showed that the peroxide value and binding capacity of bigels were affected by the type of hydrogel used. However, their fatty acid profile, p-anisidine value, oxidative stability, and texture remained unchanged. Using bigels as fat replacers, cookies were obtained with a hardness similar to those with original shortening, showing the potential of bigels for use in foods.
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Among the most lethal forms of cancer, malignant brain tumors persist as one of the greatest challenges faced by oncologists, where nanotechnology-driven theranostics can play a critical role in developing novel polymer-based supramolecular nanoarchitectures with multifunctional and multi-modal characteristics to fight cancer. However, it is virtually a consensus that, besides the complexity of active delivering anticancer drugs by the nanocarriers to the tumor site, the current evaluation methods primarily relying on in vitro assays and in vivo animal models have been accounted for the low translational effectiveness to clinical applications. In this view, the chick chorioallantoic membrane (CAM) assay has been increasingly recognized as one of the best preclinical models to study the effects of anticancer drugs on the tumor microenvironment (TME). Thus, in this study, we designed, characterized, and developed novel hybrid nanostructures encompassing chemically functionalized carboxymethylcellulose (CMC) with mitochondria-targeting pro-apoptotic peptide (KLA) and cell-penetrating moiety (cysteine, CYS) with fluorescent inorganic semiconductor (Ag-In-S, AIS) for simultaneously bioimaging and inducing glioblastoma cancer cell (U-87 MG, GBM) death. The results demonstrated that the CMC-peptide macromolecules produced supramolecular vesicle-like nanostructures with aqueous colloidal stability suitable as nanocarriers for passive and active targeting of cancer tumors. The optical properties and physicochemical features of the nanoconjugates confirmed their suitability as photoluminescent nanoprobes for cell bioimaging and intracellular tracking. Moreover, the results in vitro demonstrated a notable killing activity towards GBM cells of cysteine-bearing CMC conjugates coupled with pro-apoptotic KLA peptides. More importantly, compared to doxorubicin (DOX), a model anticancer drug in chemotherapy that is highly toxic, these innovative nanohybrids nanoconjugates displayed higher lethality against U-87 MG cancer cells. In vivo CAM assays validated these findings where the nanohybrids demonstrated a significant reduction of GBM tumor progression (41% area) and evidenced an antiangiogenic activity. These results pave the way for developing polymer-based hybrid nanoarchitectonics applied as targeted multifunctional theranostics for simultaneous imaging and therapy against glioblastoma while possibly reducing the systemic toxicity and side-effects of conventional anticancer chemotherapeutic agents.
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Antineoplásicos , Neoplasias Encefálicas , Glioblastoma , Pontos Quânticos , Animais , Antineoplásicos/química , Neoplasias Encefálicas/tratamento farmacológico , Carboximetilcelulose Sódica/química , Linhagem Celular Tumoral , Cisteína , Doxorrubicina/química , Glioblastoma/tratamento farmacológico , Nanoconjugados/uso terapêutico , Polímeros/uso terapêutico , Pontos Quânticos/química , Nanomedicina Teranóstica , Microambiente TumoralRESUMO
Erythrosine is a dye approved for medical use that has shown promising photodynamic activity, allowing for the inactivation of microorganisms and activity against malignant cells. Despite the great photodynamic potential, erythrosine exhibits hydrophilicity, negatively impacting its action in biological membranes. Therefore, the incorporation of erythrosine in micellar polymeric systems, such as poloxamers, may overcome this limitation. Moreover, using bioadhesive and thermoresponsive polymers to combine in situ gelation and bioadhesion may enhance retention of this topically applied drug. In this work, mucoadhesive and thermoresponsive micellar systems were prepared containing erythrosine in two states: the native form (ERI) and the disodium salt (ERIs). The systems were evaluated based on the effect of ERI/ERIs on the micellar structure of the binary polymer mixtures. Optimised combinations of poloxamer 407 (polox407) and mucoadhesive sodium carboxymethylcellulose (NaCMC) or hydroxypropyl methylcellulose (HPMC) were used as micellar systems for ERI or ERIs delivery. The systems were studied with respect to theoretical interactions, qualitative composition, morphology, and micellar properties. In silico modelling indicated a higher interaction of the drug with poly(ethylene oxide) (PEO) than poly(propylene oxide) (PPO) fragments of polox407. Systems containing NaCMC displayed a repulsive effect in the presence of erythrosine, due to the polymer's charge density. Both systems could convert the photosensitizer in its monomeric form, ensuring photodynamic activity. In these mixtures, crystallinity, critical micellar temperature and enthalpy of polox407 micellisation were reduced, and micellar size, evaluated by transmission electron microscopy (TEM), showed low impact of ERI/ERIs in HPMC preparations. Aiming toward photodynamic applications, the findings showed how ERI or ERIs can affect the micellar formation of gels composed of 17.5% (w/w) polox407 and 3% (w/w) HPMC or 1% (w/w) NaCMC, important for understating their behaviour and future utilisation as erythrosine delivery systems.
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Eritrosina , Poloxâmero , Celulose , Simulação por Computador , Derivados da HipromeloseRESUMO
Systems composed of bioadhesive and thermoresponsive polymers can combine in situ gelation with bio/mucoadhesion, enhancing retention of topically applied drugs. The effect of bioadhesive sodium carboxymethylcellulose (NaCMC) and hydroxypropyl methylcellulose cellulose (HPMC) on the properties of thermoresponsive Pluronic® F127 (F127) was explored, including micellization and the mucoadhesion. A computational analysis between these polymers and their molecular interactions were also studied, rationalising the design of improved binary polymeric systems for pharmaceutical and biomedical applications. The morphological characterization of polymeric systems was conducted by SEM. DSC analysis was used to investigate the crystallization and micellization enthalpy of F127 and the mixed systems. Micelle size measurements and TEM micrographs allowed for investigation into the interference of cellulose derivatives on F127 micellization. Both cellulose derivatives reduced the critical micellar concentration and enthalpy of micellization of F127, altering hydrodynamic diameters of the aggregates. Mucoadhesion performance was useful to select the best systems for mucosal application. The systems composed of 17.5% (w/w) F127 and 3% (w/w) HPMC or 1% (w/w) NaCMC are promising as topical drug delivery systems, mainly on mucosal surfaces. They were biocompatible when tested against Artemia salina, and also able to release a model of hydrophilic drug in a controlled manner.
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Micelas , Poloxâmero , Derivados da Hipromelose , Metilcelulose , ReologiaRESUMO
The main objectives of this study were to evaluate the chemical constitution and allergenic potential of red propolis extract (RPE). They were evaluated, using high performance liquid chromatography (HPLC) and the release of ß-hexosaminidase, respectively. A plethora of biologically active polyphenols and the absence of allergic responses were evinced. RPE inhibited the release of ß-hexosaminidase, suggesting that the extract does not stimulate allergic responses. Additionally, the physicochemical properties and antibacterial activity of hydrogel membranes loaded with RPE were analyzed. Bio-polymeric hydrogel membranes (M) were obtained using 5% carboxymethylcellulose (M1 and M2), 1.0% of citric acid (M3) and 10% RPE (for all). Their characterization was performed using thermal analysis, Fourier transform infrared (FTIR), total phenolic content, phenol release test and, antioxidant activity through 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and Ferric Reducing Antioxidant Power (FRAP). The latter appointed to the similar antioxidant capacity of the M1, M2 and M3. The degradation profiles showed higher thermostability to M3, followed by M2 and M1. The incorporation of RPE into the matrices and the crosslinking of M3 were evinced by FTIR. There were differences in the release of phenolic compounds, with a higher release related to M1 and lower in the strongly crosslinked M3. The degradation profiles showed higher thermostability to M3, followed by M2 and M1. The antibacterial activity of the membranes was determined using the disc diffusion assay, in comparison with controls, obtained in the same way, without RPE. The membranes elicited antibacterial activity against Staphylococcus aureus and Staphylococcus epidermidis, with superior performance over M3. The hydrogel membranes loaded with RPE promote a physical barrier against bacterial skin infections and may be applied in the wound healing process.
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Própole/química , Administração Tópica , Alérgenos/química , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/farmacologia , Bandagens , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biopolímeros/administração & dosagem , Biopolímeros/química , Biopolímeros/farmacologia , Brasil , Linhagem Celular , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Hidrogéis , Técnicas In Vitro , Mastócitos/efeitos dos fármacos , Mastócitos/enzimologia , Mastócitos/imunologia , Membranas Artificiais , Fenóis/química , Própole/administração & dosagem , Própole/farmacologia , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Termogravimetria , beta-N-Acetil-Hexosaminidases/metabolismoRESUMO
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 22.3â¯nm particle-size were synthesized. They were not toxic to HGF cells at concentrations tested that were antimicrobial, however they caused significant cytotoxicity (89 %, pâ¯<⯠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 (pâ¯<⯠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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Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Dentina/microbiologia , Nanopartículas Metálicas , Prata/farmacologia , Carboximetilcelulose Sódica/química , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Gengiva/citologia , Humanos , Testes de Sensibilidade MicrobianaRESUMO
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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BACKGROUND: Mathematical modeling in modified drug release is an important tool that allows predicting the release rate of drugs in their surrounding environment and elucidates the transport mechanisms involved in the process. OBJECTIVE: The aim of this work was to develop a mathematical model that allows evaluating the release profile of drugs from polymeric carriers in which the swelling phenomenon is present. METHODS: Swellable matrices based on ionic complexes of alginic acid or carboxymethylcellulose with ciprofloxacin were prepared and the effect of adding the polymer sodium salt on the swelling process and the drug release was evaluated. Experimental data from the ciprofloxacin release profiles were mathematically adjusted, considering the mechanisms involved in each stage of the release process. RESULTS: A proposed model, named "Dual Release" model, was able to properly fit the experimental data of matrices presenting the swelling phenomenon, characterized by an inflection point in their release profile. This entails applying the extended model of Korsmeyer-Peppas to estimate the percentage of drug released from the first experimental point up to the inflection point and then a model called Lumped until the final time, allowing to adequately represent the complete range of the drug release profile. Different parameters of pharmaceutical relevance were calculated using the proposed model to compare the profiles of the studied matrices. CONCLUSION: The "Dual Release" model proposed in this article can be used to predict the behavior of complex systems in which different mechanisms are involved in the release process.
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Ácido Algínico/química , Ciprofloxacina/química , Preparações de Ação Retardada/química , Polieletrólitos/química , Liberação Controlada de Fármacos , Humanos , Modelos TeóricosRESUMO
Poincianella pluviosa has already been described as capable of healing skin wounds. In an attempt to prolong contact of the drug with the wound, it was proposed in this study to evaluate wound healing using a crude extract (CE) of P. pluviosa incorporated in carboxymethylcellulose polymer films. The chromatographic profile of the semipurified fraction of P. pluviosa was evaluated by ultra-high performance liquid chromatography (UHPLC), confirming the compounds gallic acid, geraniin, and ellagic acid. The films were evaluated for their physical and mechanical properties, water vapor permeability, moisture absorption capacity, and FTIR spectroscopy. For in vivo experiments, wounds were made on the back of rats and treated daily for 4, 7, 10, or 14 days with film containing CE or control film. At the end of each period, skin permeation analysis and histological analysis were made using re-epithelialisation, cell proliferation, and collagen formation. Statistical significance was determined by GraphPad Prism using t test and Mann-Whitney test. Anti-staphylococcal activity was evaluated with standard strains of Staphylococcus aureus, methicillin-resistant, and coagulase negative. It was demonstrated that the presence of CE in the films increased the capacity to absorb water and decreased resistance and permeability. The CE of the film permeated the skin, reaching the dermis and was able to influence re-epithelisation, cell proliferation, and collagen formation. Satisfactory results were observed against S. aureus strains, particularly coagulase negative. Films with CE of P. pluviosa can be an alternative in the wound healing, protecting against opportunistic infections and giving comfort to the patient.
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Antibacterianos/farmacologia , Fabaceae/química , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Cromatografia Líquida de Alta Pressão , Masculino , Casca de Planta/química , Polímeros , Ratos , Pele/efeitos dos fármacos , Pele/lesões , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
A robust and sustainable sensor for the detection of Al(III) ions in water was developed by immobilization of anthocyanin (AN) from black rice in a film formed by carboxymethylcellulose (CMC) and starch. Characterization of the films was performed using solubility, thickness, FTIR, and mechanical analysis. The film exhibited an irreversible color change from red to purple in response to the presence of Al(III). The best colorimetric response of the sensor was observed at pH 4.5 and a time of 60â¯min, achieving the detection of 3â¯mgâ¯L-1 of Al(III). For concentrations higher than 5â¯mgâ¯L-1, the sensor response time decreased to 20â¯min. The minimum Al(III) concentration detected with the naked eye was lower than the maximum permissible concentrations in aqueous effluents according to different legislations, indicating the potential of this study to develop sensors for the detection of Al(III).
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This study evaluated the removal of silver nanoparticles (AgNPs), coated with different stabilizers, from aqueous media using the electrocoagulation technique. The AgNPs dispersions were synthesized by chemical reduction with silver nitrate as precursor, sodium borohydride as reducing agent and sodium carboxymethylcellulose (CMC), polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) as stabilizers with initial concentrations of 1 and 3% (w/v). The dispersions were named AgNPs-CMC1, AgNPs-CMC3, AgNPs-PVA1, AgNPs-PVA3, AgNPs-PVP1, and AgNPs-PVP3. Electrocoagulation treatments of AgNPs-PVA1, AgNPs-PVP1 and AgNPs-PVP3 dispersions resulted in total silver removals above 99.90% in 10â min. For the AgNPs-PVP3 dispersion 99.98% of removal was obtained in 20â min. After 15â min of electrolysis, The AgNPs-CMC1 and AgNPs-CMC3 dispersions showed a reduction in total silver concentration of 71.72 and 52.15%, respectively. Therefore, these results showed that the removal of AgNPs from the aqueous medium by electrocoagulation is possible, but their efficiency and viability depends on the nature, the molecular structure and the concentration of stabilizers. Furthermore, the toxicity analysis using the Vibrio fischeri bacteria demonstrated that only the dispersions stabilized with PVP became suitable for disposal after the electrocoagulation treatment.
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Nanopartículas Metálicas , Eletrocoagulação , Álcool de Polivinil , Povidona , PrataRESUMO
In the present work the effect of three factors: pH, temperature and type of microorganism using a factorial design 32x2 was evaluated on: growth, total cellulases hydrolytic activity (FPases), endoglucanases hydrolytic activity (CMCases), free reducing sugars (FRS), glucose, sucrose, and alcohol production using a culture medium based on mineral salts added with cladodes flour of Opuntia ficus-indica at 20% as the unique carbon source. Two wild microorganisms were used, Acinetobacter pittii a bacteria isolated from decaying cladodes, and Kluyveromyces marxianus a yeast isolated from termite stomach. The maximum hydrolytic activities were obtained with Acinetobacter pittii at 37⯰C and pH 6.5 for total cellulases (0.67⯱â¯0.02 IU/ml) and for endoglucanases (0.23⯱â¯0.02 IU/ml) at 24 and 4â¯h. The maximum production of alcohol was 12.98⯱â¯0.06â¯g/L obtained with Kluyveromyces marxianus at 4â¯h with conditions of 40⯰C and pH 5.5.
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RESUMEN La creciente demanda de productos libres de gluten ha dado lugar al estudio y desarrollo de alimentos que suplan las necesidades de los consumidores. El objetivo de esta investigación fue elaborar productos libres de gluten tipo tallarín y evaluar sus propiedades fisicoquímicas. Para ello, se empleó plátano o yuca como fuentes alternativas a la harina de trigo. Se determinaron sus propiedades fisicoquímicas. Se extrajeron harina y almidones y, a partir de ellas, se evaluaron sus propiedades térmicas, empleando calorimetría de barrido diferencial y termogravimetría. Se formularon y elaboraron productos similares a los tallarines empleando las harinas y se analizaron sus propiedades fisicoquímicas, microbiológicas y sensoriales, usando, como control, un producto comercial de trigo. La yuca presentó mayor humedad que el plátano, lo que está relacionado con su susceptibilidad a la degradación. En el análisis termogravimétrico, los productos de yuca mostraron mayor reducción de peso en la zona de alta volatilidad, asociado a la pérdida de humedad. Las harinas y los almidones de plátano presentaron temperaturas de gelatinización mayores que las registradas para los productos de yuca. La humedad y acidez de los tallarines elaborados presentaron valores dentro de la norma (NTC 1055-2014). En ambos casos, su contenido de cenizas fue superior al fideo comercial. Los tallarines elaborados, se pueden considerar inocuos, con buenos parámetros de aceptación sensorial. Estos resultados constituyen un punto de partida en el estudio y aplicación de fuentes de harinas y almidones no tradicionales, permitiendo la generación de valor agregado a cultivos de importancia en la región.
ABSTRACT The growing demand of free gluten products has shown the necessity to study and develop new products in order to supply the consumer request. The objective of this research was to elaborate gluten-free products similar to noodles and to evaluate their physicochemical properties. Plantain or cassava were employed to replace wheat flour. Physical and chemical properties were determined in plantain and cassava samples. Both, Plantain and Cassava Flour and their starches were extracted. Thermal characteristics of flour and starch were evaluated employing differential scanning calorimetry and thermal gravimetric analysis. Products similar to noodle were formulated and elaborated employing plantain or cassava flour. Noodle physicochemical, microbiological and sensorial characteristics were analyzed, employing a commercial product as a control. Cassava presented higher humidity values than plantain, it is related to their susceptibility to degradation. In thermogravimetric analysis, cassava products shown upper weight reduction in high volatility zone associated to humidity lost. Plantain flours and starches presented gelatinization temperatures higher than registered for cassava products. Both plantain and cassava noodles presented humidity and acidity values according to the legal legislation (NTC 1055-2014). Developed products showed ash content higher than commercial noodles. According to microbiological and sensorial analyses, the plantain and cassava products could be considered innocuous with good consumer acceptation. These results could constitute a starting point in the study and application of different flours and starches from non-traditional sources, which allow to increase the value of crops in the region.
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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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Bacterial cellulose/carboxymethylcelullose (BC/CMC) biocomposites with different DS-CMC (DS from 0.7 to 1.2) were developed in order to evaluate their impact as a drug delivery system. Biocomposites were loaded with methotrexate (MTX) as an alternative for the topical treatment of psoriasis. Scanning electron microscopy and atomic force microscopy showed that the CMC coated the cellulose nanofibers, leading to the decrease of the elastic modulus as the DS of CMC increased. BC/CMC0.9 exhibited the lower liquid uptake (up to 11 times lower), suggesting that the more linear structure of the intermediate substitute CMC grade (0.9) was able to interact more strongly with BC, resulting in a denser structure. All samples showed a typical burst release effect in the first 15min of test, however the BC/CMC0.9 biocomposite promoted a slight lowering of MTX release rates, suggesting that the DS of CMC can be considered the key factor to modulate the BC properties.
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Materiais Biocompatíveis/química , Carboximetilcelulose Sódica/química , Fármacos Dermatológicos/química , Liberação Controlada de Fármacos , Gluconacetobacter xylinus/metabolismo , Metotrexato/química , Nanofibras/química , Meios de Cultura/química , Sistemas de Liberação de Medicamentos , Módulo de Elasticidade , Gluconacetobacter xylinus/crescimento & desenvolvimento , Porosidade , Solubilidade , Engenharia TecidualRESUMO
In this study, new eco-friendly hydrogel adsorbents were synthesized based on carboxymethylcellulose (CMC, degree of substitution [DS] = 0.7) chemically cross-linked with citric acid (CA) using a green process in aqueous solution and applied for the adsorption of methylene blue (MB). Spectroscopic analyses demonstrated the mechanism of cross-linking through the reaction of hydroxyl functional groups from CMC with CA. These CMC hydrogels showed very distinct morphological features dependent on the extension of cross-linking and their nanomechanical properties were drastically increased by approximately 300% after cross-linking with 20% CA (e.g. elastic moduli from 80 ± 15 to 270 ± 50â MPa). Moreover, they were biocompatible using an in vitro cell viability assay in contact with human osteosarcoma-derived cells (SAOS) for 24â h. These CMC-based hydrogels exhibited adsorption efficiency above 90% (24â h) and maximum removal capacity of MB from 5 to 25â mgâ g-1 depending on the dye concentration (from 100 to 500â mgâ L-1), which was used as the model cationic organic pollutant. The adsorption of process of MB was well-fit to the pseudo-second-order kinetics model. The desorption of MB by immersion in KCl solution (3â molâ L-1, 24â h) showed a typical recovery efficiency of over 60% with conceivable reuse of these CMC-based hydrogels. Conversely, CMC hydrogels repelled methyl orange dye used as model anionic pollutant, proving the mechanism of adsorption by the formation of charged polyelectrolyte/dye complexes.