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1.
Molecules ; 26(7)2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33917359

RESUMEN

The aim of the study was to create a mathematical model useful for monitoring the release of bioactive aldehydes covalently bonded to the chitosan by reversible imine linkage, considered as a polymer-drug system. For this purpose, two hydrogels were prepared by the acid condensation reaction of chitosan with the antifungal 2-formyl-phenyl-boronic acid and their particularities; influencing the release of the antifungal aldehyde by shifting the imination equilibrium to the reagents was considered, i.e., the supramolecular nature of the hydrogels was highlighted by polarized light microscopy, while scanning electron microscopy showed their microporous morphology. Furthermore, the in vitro fungicidal activity was investigated on two fungal strains and the in vitro release curves of the antifungal aldehyde triggered by the pH stimulus were drawn. The theoretical model was developed starting from the hypothesis that the imine-chitosan system, both structurally and functionally, can be assimilated, from a mathematical point of view, with a multifractal object, and its dynamics were analyzed in the framework of the Scale Relativity Theory. Thus, through Riccati-type gauges, two synchronous dynamics, one in the scale space, associated with the fungicidal activity, and the other in the usual space, associated with the antifungal aldehyde release, become operational. Their synchronicity, reducible to the isomorphism of two SL(2R)-type groups, implies, by means of its joint invariant functions, bioactive aldehyde compound release dynamics in the form of "kink-antikink pairs" dynamics of a multifractal type. Finally, the theoretical model was validated through the experimental data.


Asunto(s)
Antifúngicos/farmacología , Quitosano/química , Liberación de Fármacos , Modelos Teóricos , Aldehídos/química , Fractales , Hidrogeles/química , Iminas/química
2.
Molecules ; 26(5)2021 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-33800798

RESUMEN

The adsorptive removal of trihalomethanes (THMs) from spiked water samples was evaluated with a series of modified polysaccharide adsorbents that contain ß-cylodextrin or chitosan. The uptake properties of these biodegradable polymer adsorbents were evaluated with a mixture of THMs in aqueous solution. Gas chromatography employing a direct aqueous injection (DAI) method with electrolytic conductivity detection enabled quantification of THMs in water at 295 K and at pH 6.5. The adsorption isotherms for the polymer-THMs was evaluated using the Sips model, where the monolayer adsorption capacities ranged between 0.04 and 1.07 mmol THMs/g for respective component THMs. Unique adsorption characteristics were observed that vary according to the polymer structure, composition, and surface chemical properties. The modified polysaccharide adsorbents display variable molecular recognition and selectivity toward component THMs in the mixed systems according to the molecular size and polarizability of the adsorbates.


Asunto(s)
Polímeros/química , Trihalometanos/análisis , Trihalometanos/aislamiento & purificación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Quitosano/química , Propiedades de Superficie , beta-Ciclodextrinas/química
3.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802469

RESUMEN

In this study, nanocomposite hydrogels composed of sodium carboxymethylated starch (CMS)-containing CuO nanoparticles (CMS@CuO) were synthesized and used as experimental wound healing materials. The hydrogels were fabricated by a solution-casting technique using citric acid as a crosslinking agent. They were characterized by Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and thermogravimetric analysis (TGA) to evaluate their physicochemical properties. In addition, swelling, antibacterial activities, antioxidant activities, cytotoxicity, and in vivo wound healing were investigated to evaluate the wound healing potential of the CMS@CuO nanocomposite hydrogels. Growth inhibition of the Gram-positive and Gram-negative pathogens, antioxidant activity, and swelling were observed in the CMS@CuO nanocomposite hydrogels containing 2 wt.% and 4 wt.% CuO nanoparticles. The hydrogel containing 2 wt.% CuO nanoparticles displayed low toxicity to human fibroblasts and exhibited good biocompatibility. Wounds created in rats and treated with the CMS@2%CuO nanocomposite hydrogel healed within 13 days, whereas wounds were still present when treated for the same time-period with CMS only. The impact of antibacterial and antioxidant activities on accelerating wound healing could be ascribed to the antibacterial and antioxidant activities of the nanocomposite hydrogel. Incorporation of CuO nanoparticles in the hydrogel improved its antibacterial properties, antioxidant activity, and degree of swelling. The present nanocomposite hydrogel has the potential to be used clinically as a novel wound healing material.


Asunto(s)
Antibacterianos/química , Antioxidantes/química , Cobre/química , Hidrogeles/química , Nanopartículas/química , Almidón/análogos & derivados , Cicatrización de Heridas/efectos de los fármacos , Animales , Antibacterianos/farmacología , Antioxidantes/farmacología , Células Cultivadas , Quitosano/química , Fibroblastos/efectos de los fármacos , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Nanocompuestos/química , Ratas , Ratas Wistar , Almidón/química , Difracción de Rayos X
4.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807862

RESUMEN

Chitosan-based edible coatings represent an eco-friendly and biologically safe preservative tool to reduce qualitative decay of fresh and ready-to-eat fruits during post-harvest life due to their lack of toxicity, biodegradability, film-forming properties, and antimicrobial actions. Chitosan-based coatings modulate or control oxidative stress maintaining in different manner the appropriate balance of reactive oxygen species (ROS) in fruit cells, by the interplay of pathways and enzymes involved in ROS production and the scavenging mechanisms which essentially constitute the basic ROS cycle. This review is carried out with the aim to provide comprehensive and updated over-view of the state of the art related to the effects of chitosan-based edible coatings on anti-oxidant systems, enzymatic and non-enzymatic, evaluating the induced oxidative damages during storage in whole and ready-to-eat fruits. All these aspects are broadly reviewed in this review, with particular emphasis on the literature published during the last five years.


Asunto(s)
Antioxidantes/química , Quitosano/química , Productos Agrícolas , Películas Comestibles , Conservación de Alimentos , Conservantes de Alimentos/química , Frutas
5.
Int J Nanomedicine ; 16: 2405-2417, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33814907

RESUMEN

Purpose: Ciprofloxacin (CIP) has poor lung targeting after oral inhalation. This study developed optimized inhalable nanostructured lipid carriers (NLCs) for CIP to enhance deposition and accumulation in deeper parts of the lungs for treatment of noncystic fibrosis bronchiectasis (NCFB). Methods: NLC formulations based on stearic acid and oleic acid were successfully prepared by hot homogenization and in vitro-characterized. CIP-NLCs were formulated into nanocomposite micro particles (NCMPs) for administration in dry powder inhalation (DPI) formulations by spray-drying (SD) using different ratios of chitosan (CH) as a carrier. DPI formulations were evaluated for drug content and in vitro deposition, and their mass median aerodynamic diameter (MMAD), fine particle fraction (FPF), fine particle dose (FPD), and emitted dose (ED) were determined. Results: The CIP-NLCs were in the nanometric size range (102.3 ± 4.6 nm), had a low polydispersity index (0.267 ± 0.12), and efficient CIP encapsulation (98.75% ± 0.048%), in addition to a spherical and smooth shape with superior antibacterial activity. The in vitro drug release profile of CIP from CIP-NLCs showed 80% release in 10 h. SD of CIP-NLCs with different ratios of CH generated NCMPs with good yield (>65%). The NCMPs had a corrugated surface, but with increasing lipid:CH ratios, more spherical, smooth, and homogenous NCMPs were obtained. In addition, there was a significant change in the FPF with increasing lipid:CH ratios (P ˂ 0.05). NCMP-1 (lipid:CH = 1:0.5) had the highest FPD (45.0 µg) and FPF (49.2%), while NCMP-3 (lipid:CH = 1:1.5) had the lowest FPF (37.4%). All NCMP powders had an MMAD in the optimum size range of 3.9-5.1 µm. Conclusion: Novel inhalable CIP NCMP powders are a potential new approach to improved target ability and delivery of CIP for NCFB treatment.


Asunto(s)
Bronquiectasia/tratamiento farmacológico , Ciprofloxacino/uso terapéutico , Portadores de Fármacos/química , Lípidos/química , Nanoestructuras/química , Administración por Inhalación , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Quitosano/química , Ciprofloxacino/administración & dosificación , Portadores de Fármacos/administración & dosificación , Liberación de Fármacos , Inhaladores de Polvo Seco , Fibrosis , Cinética , Liposomas , Pulmón , Pruebas de Sensibilidad Microbiana , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Electricidad Estática
6.
Int J Nanomedicine ; 16: 2533-2553, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33824590

RESUMEN

Purpose: The present study was intended to fabricate chitosan (Ch)-tamarind gum polysaccharide (TGP) polyelectrolyte complex stabilized cubic nanoparticles of simvastatin and evaluate their potential against human breast cancer cell lines. Materials and Methods: The antisolvent precipitation method was used for formulation of nanoparticles. Factorial design (32) was utilized as a tool to analyze the effect of Ch and TGP concentration on particle size and entrapment efficiency of nanoparticles. Results: Formulated nanoparticles showed high entrapment efficiency (67.19±0.42-83.36±0.23%) and small size (53.3-383.1 nm). The present investigation involved utilization of two biological membranes (egg and tomato) as biological barriers for drug release. The study revealed that drug release from tomato membranes was retarded (as compared to egg membranes) but the release pattern matched that of egg membranes. All formulations followed the Baker-Lansdale model of drug release irrespective of the two different biological barriers. Stability studies were carried out for 45 days and exhibited less variation in particle size as well as a reduction in entrapment efficiency. Simvastatin loaded PEC stabilized nanoparticles exhibited better control on growth of human breast cancer cell lines than simple simvastatin. An unusual anticancer effect of simvastatin nanoparticles is also supported by several other research studies. Conclusion: The present study involves first-time synthesis of Ch-TGP polyelectrolyte complex stabilized nanoparticles of simvastatin against MCF-7 cells. It recommends that, in future, theoretical modeling and IVIVC should be carried out for perfect designing of delivery systems.


Asunto(s)
Quitosano/química , Nanopartículas/química , Gomas de Plantas/química , Polielectrolitos/química , Polisacáridos/química , Simvastatina/farmacología , Tamarindus/química , Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Humanos , Células MCF-7 , Nanopartículas/ultraestructura , Tamaño de la Partícula , Espectrofotometría Infrarroja , Electricidad Estática
7.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33801871

RESUMEN

Recently, nano- and micro-particulate systems have been widely utilized to deliver pharmaceutical compounds to achieve enhanced therapeutic effects and reduced side effects. Poly (DL-lactide-co-glycolide) (PLGA), as one of the biodegradable polyesters, has been widely used to fabricate particulate systems because of advantages including controlled and sustained release, biodegradability, and biocompatibility. However, PLGA is known for low encapsulation efficiency (%) and insufficient controlled release of water-soluble drugs. It would result in fluctuation in the plasma levels and unexpected side effects of drugs. Therefore, the purpose of this work was to develop microcapsules loaded with alginate-coated chitosan that can increase the encapsulation efficiency of the hydrophilic drug while exhibiting a controlled and sustained release profile with reduced initial burst release. The encapsulation of nanoparticles in PLGA microcapsules was done by the emulsion solvent evaporation method. The encapsulation of nanoparticles in PLGA microcapsules was confirmed by scanning electron microscopy and confocal microscopy. The release profile of hydrophilic drugs can further be altered by the chitosan coating. The chitosan coating onto alginate exhibited a less initial burst release and sustained release of the hydrophilic drug. In addition, the encapsulation of alginate nanoparticles and alginate nanoparticles coated with chitosan in PLGA microcapsules was shown to enhance the encapsulation efficiency of a hydrophilic drug. Based on the results, this delivery system could be a promising platform for the high encapsulation efficiency and sustained release with reduced initial burst release of the hydrophilic drug.


Asunto(s)
Preparaciones de Acción Retardada/farmacocinética , Nanopartículas/química , Preparaciones Farmacéuticas/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacocinética , Alginatos/química , Biodegradación Ambiental , Cápsulas , Quitosano/química , Preparaciones de Acción Retardada/química , Portadores de Fármacos , Liberación de Fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo , Microesferas , Nanopartículas/ultraestructura , Tamaño de la Partícula , Preparaciones Farmacéuticas/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química
8.
J Chromatogr A ; 1643: 462072, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33789194

RESUMEN

Chemical modification of biological materials is indispensable for enrichment of phosphorylated peptides. In this work, we synthesized a biomimetic honeycombed affinity chromatography (IMAC) adsorbent by preparing Crosslinked Chitosan, chelating aminomethyl phosphate decorated with Ti (IV) cation. The as-prepared CTSM@AMPA-Ti4+ composites with stable structure, low steric hindrance, and high Ti4+ loading amount were used as a promising adsorbent for enrichment of phosphopeptides. CTSM@AMPA-Ti4+ showed extremely high sensitivity (0.4 fmol) and selectivity at a low composition molar ratio of ß-casein/BSA (1:1000). What's more, it can keep its performance in the case that used to capture phosphorylated peptides from standard protein ten times or soaking in the acid/base solution for a long time. In addition, CTSM@AMPA-Ti4+ successfully captured 35 phosphorylated peptides from human saliva. This study offers a way about diversiform functionalization of CTSM in phosphoproteome analysis and disease research.


Asunto(s)
Quitosano/química , Cromatografía de Afinidad/métodos , Fosfopéptidos/análisis , Materiales Biomiméticos/química , Caseínas/metabolismo , Humanos , Organofosfonatos/química , Fosfopéptidos/aislamiento & purificación , Saliva/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Titanio/química
9.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668995

RESUMEN

Chitosan and polyethylene glycol (PEG-600) membranes were synthesized and crosslinked with 3-aminopropyltriethoxysilane (APTES). The main purpose of this research work is to synthesize RO membranes which can be used to provide desalinated water for drinking, industrial and agricultural purposes. Hydrogen bonding between chitosan and PEG was confirmed by displacement of the hydroxyl absorption peak at 3237 cm-1 in pure chitosan to lower values in crosslinked membranes by using FTIR. Dynamic mechanical analysis revealed that PEG lowers Tg of the modified membranes vs. pure chitosan from 128.5 °C in control to 120 °C in CS-PEG5. SEM results highlighted porous and anisotropic structure of crosslinked membranes. As the amount of PEG was increased, hydrophilicity of membranes was increased and water absorption increased up to a maximum of 67.34%. Permeation data showed that flux and salt rejection value of the modified membranes was increased up to a maximum of 80% and 40.4%, respectively. Modified films have antibacterial properties against Escherichia coli as compared to control membranes.


Asunto(s)
Quitosano/química , Filtración/métodos , Membranas Artificiales , Polietilenglicoles/química , Propilaminas/química , Silanos/química , Antibacterianos/farmacología , Reactivos de Enlaces Cruzados/química , Escherichia coli/efectos de los fármacos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo , Ósmosis , Permeabilidad , Polímeros/química , Polímeros/farmacología , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Agua/química
10.
Food Chem ; 354: 129591, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33756315

RESUMEN

Recently, Pickering emulsions have been considered as an efficient method to maintain and protect the functional properties of essential oils against the harsh conditions. In this research, the encapsulation of d-limonene, as an aromatic component with several distinct properties, was conducted through optimizing the production of Pickering emulsions stabilized by chitosan nanoparticles (CSNPs) and using the response surface methodology; independent variables were different concentrations of CSNPs (0.43, 0.25, and 0.07% w/v) and ratio of d-limonene to Pickering emulsions (5, 15, and 25%). The stability of the emulsions increased at higher contents of the CSNPs. By increasing the concentration of CSNPs and ratio of d-limonene to Pickering emulsion, viscosity of Pickering emulsions was considerably increased. Considering the chemical interactions, thermal behaviors, and crystallinity of samples, CSNPs can be used as an appropriate stabilizer for d-limonene-loaded emulsions and a food grade delivery carrier for the bioactive compounds.


Asunto(s)
Quitosano/química , Limoneno/química , Nanopartículas/química , Portadores de Fármacos/química , Emulsiones , Tamaño de la Partícula , Temperatura , Viscosidad
11.
Food Chem ; 354: 129553, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33756316

RESUMEN

Aiming the simplification of the production of chitosan nanoparticles as an encapsulating material, the primary approach of this study was to investigate the extraction of active compounds from acerola-pulp by-products directly in chitosan solution by using tip sonication. The results have shown that chitosan solution can be used as a good solvent, mainly for total phenolic compounds (TPC) extraction (1792.7 mg/100 g of dry by-product). The extract was submitted to ionic gelation process using, as counter-ion, the sodium tripolyphosphate to form loaded nanoparticles with TPC. The suspension was applied as protective coatings on the guavas. The nanoengineered coatings provided an effective barrier that delayed the maturation and maintained the green pigmentation for longer periods along with good firmness. To the best of our knowledge, this was the first study that uses chitosan solution as extraction solvent of TPC from food byproducts in order to facilitate the encapsulation process.


Asunto(s)
Quitosano/química , Almacenamiento de Alimentos , Malpighiaceae/química , Fenoles/aislamiento & purificación , Psidium/química , Ácido Ascórbico/química , Cápsulas , Nanopartículas/química , Fenoles/química , Soluciones
12.
Carbohydr Polym ; 259: 117762, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33674015

RESUMEN

Biopolymer-based nanomaterials have been developed as antimicrobial and anticancer agents due to their advanced physical, chemical and biomedical characteristics. Herein, chitosan-copper oxide nanomaterial was, successfully synthesized by a green method. In this process, copper salt was nucleated with Psidium guajava leaves extract in order to form the nanomaterial in the chitosan network. Attenuated total reflection-fourier transform, infrared spectroscopy, X-ray diffraction, Dynamic light scattering, Transmission electron microscope, Field emission scanning electron microscopy/Energy dispersive X-ray analysis, X-ray photoelectron spectroscopy and Photoluminescence spectroscopy techniques were, employed to characterize the synthesized nanomaterial. The average size of the nanomaterial was identified to be ∼52.49 nm with XRD. The antibacterial study of CCuO NM showed higher activity than the commercial amoxicillin against gram-positive (G + ve) (Staphylococcus aureus, Bacillus subtilis) and gram-negative (G-ve) bacteria (Klebsiella pneumonia, Escherichia coli). CCuO NM showed in-vitro anticancer potential against human cervical cancer cells (Hela) with an IC50 concentration of 34.69 µg/mL. Photoluminescence spectrum of CCuO NM showed a green emission (oxygen vacancies) observed at ∼516 nm, which is attributed to the generation of reactive oxygen species (ROS) by the nanomaterial, which is believed, to be responsible for the biocidal (cell death) effects. These results suggested that CCuO is a promising nanomaterial that could be suitable for advanced applications in the healthcare industries.


Asunto(s)
Antibacterianos/química , Antineoplásicos/química , Quitosano/química , Cobre/química , Nanoestructuras/química , Animales , Antibacterianos/farmacología , Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Células HeLa , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Nanoestructuras/toxicidad , Tamaño de la Partícula , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Psidium/química , Psidium/metabolismo , Especies Reactivas de Oxígeno/metabolismo
13.
Int J Mol Sci ; 22(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652598

RESUMEN

The search for the perfect bone graft material is an important topic in material science and medicine. Despite human bone being the ideal material, due to its composition, morphology, and familiarity with cells, autografts are widely considered demanding and cause additional stress to the patient because of bone harvesting. However, human bone from tissue banks can be used to prepare materials in eligible form for transplantation. Without proteins and fats, the bone becomes a non-immunogenic matrix for human cells to repopulate in the place of implantation. To repair bone losses, the granulate form of the material is easy to apply and forms an interconnected porous structure. A granulate composed of ß-tricalcium phosphate, pulverized human bone, and chitosan-a potent biopolymer applied in tissue engineering, regenerative medicine, and biotechnology-has been developed. A commercial encapsulator was used to obtain granulate, using chitosan gelation upon pH increase. The granulate has been proven in vitro to be non-cytotoxic, suitable for MG63 cell growth on its surface, and increasing alkaline phosphatase activity, an important biological marker of bone tissue growth. Moreover, the granulate is suitable for thermal sterilization without losing its form-increasing its convenience for application in surgery for guided bone regeneration in case of minor or non-load bearing voids in bone tissue.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Huesos/metabolismo , Fosfatos de Calcio , Quitosano , Ensayo de Materiales , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Línea Celular , Quitosano/química , Quitosano/farmacología , Humanos
14.
Molecules ; 26(4)2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33672365

RESUMEN

Chitosan is industrially acquired by the alkaline N-deacetylation of chitin. Chitin belongs to the ß-N-acetyl-glucosamine polymers, providing structure, contrary to α-polymers, which provide food and energy. Another ß-polymer providing structure is hyaluronan. A lot of studies have been performed on chitosan to explore its industrial use. Since chitosan is biodegradable, non-toxic, bacteriostatic, and fungistatic, it has numerous applications in medicine. Hyaluronan, one of the major structural components of the extracellular matrix in vertebrate tissues, is broadly exploited in medicine as well. This review summarizes the main areas where these two biopolymers have an impact. The reviewed areas mostly cover most medical applications, along with non-medical applications, such as cosmetics.


Asunto(s)
Quitosano/química , Ácido Hialurónico/química , Humanos , Medicina
15.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672446

RESUMEN

Over the past decade, reckless usage of synthetic pesticides and fertilizers in agriculture has made the environment and human health progressively vulnerable. This setting leads to the pursuit of other environmentally friendly interventions. Amongst the suggested solutions, the use of chitin and chitosan came about, whether alone or in combination with endophytic bacterial strains. In the framework of this research, we reported an assortment of studies on the physico-chemical properties and potential applications in the agricultural field of two biopolymers extracted from shrimp shells (chitin and chitosan), in addition to their uses as biofertilizers and biostimulators in combination with bacterial strains of the genus Bacillus sp. (having biochemical and enzymatic properties).


Asunto(s)
Bacillus/metabolismo , Quitina/metabolismo , Quitosano/metabolismo , Productos Agrícolas/metabolismo , Exoesqueleto/química , Animales , Conformación de Carbohidratos , Quitina/química , Quitina/aislamiento & purificación , Quitosano/química , Quitosano/aislamiento & purificación , Crustáceos
16.
Carbohydr Polym ; 260: 117799, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712147

RESUMEN

Bacillus amyloliquefaciens strain PPL shows a potential for the control of phytopathogenic fungi. In the present study, upon growing the strain PPL on various forms of chitosan (0.5 % powder, 0.1 % soluble, and 0.15 % colloidal) as the carbon source, the antifungal activity on tomato Fusarium wilt correlated with the activity of chitosanase and ß-1,3-glucanase. The colloidal substrate-based strain PPL fermentation displayed the highest degree of spore germination inhibition (79.5 %) and biocontrol efficiency (76.0 %) in tomato by increased biofilm formation. The colloidal culture upregulated the expression of chitosanase gene (5.9-fold), and the powder attributed to the expression of cyclic lipopeptides-genes (2.5-5.7 fold). Moreover, the three chitosan cultures induced the morphological changes of Fusarium oxysporum. These results suggest that the choice of growth substrate synergistically affects the production of secondary metabolites by PPL strain, and consequently its antifungal activity.


Asunto(s)
Quitosano/química , Polímeros/química , Antifúngicos/metabolismo , Antifúngicos/farmacología , Bacillus amyloliquefaciens/enzimología , Bacillus amyloliquefaciens/crecimiento & desarrollo , Bacillus amyloliquefaciens/fisiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Técnicas de Cultivo Celular por Lotes , Biopelículas , Fusarium/efectos de los fármacos , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Lipopéptidos/metabolismo , Lycopersicon esculentum/microbiología
17.
Carbohydr Polym ; 260: 117808, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712154

RESUMEN

In the present study, a novel synthetic tissue adhesive material capable of sealing wounds without the use of any crosslinking agent was developed by conjugating thermosensitive hexanoyl glycol chitosan (HGC) with gallic acid (GA). The degree of N-gallylation was manipulated to prepare GA-HGCs with different GA contents. GA-HGCs demonstrated thermosensitive sol-gel transition behavior and formed irreversible hydrogels upon natural oxidation of the pyrogallol moieties in GA, possibly leading to GA-HGC crosslinks through intra/intermolecular hydrogen bonding and chemical bonds. The GA-HGC hydrogels exhibited self-healing properties, high compressive strength, strong tissue adhesive strength and biodegradability that were adjustable according to the GA content. GA-HGCs also presented excellent biocompatibility and wound healing effects. The results of in vivo wound healing efficacy studies on GA-HGC hydrogels indicated that they significantly promote wound closure and tissue regeneration by upregulating growth factors and recruiting fibroblasts compared to the untreated control group.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Ácido Gálico/química , Animales , Materiales Biocompatibles/farmacología , Fuerza Compresiva , Hidrogeles/química , Hidrogeles/farmacología , Reología , Porcinos , Adhesivos Tisulares/química , Cicatrización de Heridas/efectos de los fármacos
18.
Carbohydr Polym ; 260: 117809, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712155

RESUMEN

Gene therapy is an emerging and promising strategy in cancer therapy where small interfering RNA (siRNA) system has been deployed for down-regulation of targeted gene and subsequent inhibition in cancer progression; some issues with siRNA, however, linger namely, its off-targeting property and degradation by enzymes. Nanoparticles can be applied for the encapsulation of siRNA thus enhancing its efficacy in gene silencing where chitosan (CS), a linear alkaline polysaccharide derived from chitin, with superb properties such as biodegradability, biocompatibility, stability and solubility, can play a vital role. Herein, the potential of CS nanoparticles has been discussed for the delivery of siRNA in cancer therapy; proliferation, metastasis and chemoresistance are suppressed by siRNA-loaded CS nanoparticles, especially the usage of pH-sensitive CS nanoparticles. CS nanoparticles can provide a platform for the co-delivery of siRNA and anti-tumor agents with their enhanced stability via chemical modifications. As pre-clinical experiments are in agreement with potential of CS-based nanoparticles for siRNA delivery, and these carriers possess biocompatibiliy and are safe, further studies can focus on evaluating their utilization in cancer patients.


Asunto(s)
Quitosano/química , Nanopartículas/química , Neoplasias/terapia , ARN Interferente Pequeño/uso terapéutico , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Portadores de Fármacos/química , Resistencia a Antineoplásicos/efectos de los fármacos , Silenciador del Gen , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , ARN Interferente Pequeño/química
19.
Carbohydr Polym ; 260: 117812, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712157

RESUMEN

A dual pH-/thermo-responsive hydrogel was designed based on a polyelectrolyte complex of polyacrylic acid (PAA) and norbornene-functionalized chitosan (CsNb), which was synergized with chemical crosslinking using bistetrazine-poly(N-isopropyl acrylamide) (bisTz-PNIPAM). The thermo-responsive polymeric crosslinker, bisTz-PNIPAM, was synthesized via reversible addition-fragmentation transfer polymerization of NIPAM. FTIR, XRD, rheological and morphological analyses demonstrated the successful formation of the polyelectrolyte network. The highly porous structure generated through the in-situ "click" reaction between Tz and Nb resulted in a higher drug loading (29.35 %). The hydrogel (COOH/NH2 mole ratio of 3:1) exhibited limited drug release (8.5 %) of 5-ASA at a pH of 2.2, but it provided an almost complete release (92 %) at pH 7.4 and 37 °C within 48 h due to the pH responsiveness of PAA, hydrogel porosity, and shrinkage behavior of PNIPAM. The hydrogels were biodegradable and non-toxic against human fibroblast cells, suggesting their considerable potential for a colon-targeted drug delivery system.


Asunto(s)
Quitosano/química , Portadores de Fármacos/química , Hidrogeles/química , Resinas Acrílicas/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Química Clic , Portadores de Fármacos/toxicidad , Liberación de Fármacos , Humanos , Hidrogeles/farmacología , Concentración de Iones de Hidrógeno , Mesalamina/química , Mesalamina/metabolismo , Porosidad , Temperatura
20.
Carbohydr Polym ; 260: 117815, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712159

RESUMEN

Chitosan is a versatile polysaccharide in different domains due to facile modification and good biodegradability. In this paper, taking advantage of such functional properties, we have developed a stabilizer agent [OCMCS-SB] produced from chitosan, and palladium was successfully immobilized on this designed stabilizer [OCMCS-SB-Pd(II)]. The obtained complex was illuminated by 13C CP-MAS NMR, FT-IR, TGA, XRD, XPS, SEM, TEM and ICP-OES analyses. Due to the interactions of primary hydroxyl groups on chitosan, Schiff base and carboxy groups, the Pd complex showed excellent reactivity (up to 99 %) and stability towards Suzuki reactions in eco-friendly medium. Subsequently, the reusability experiments for OCMCS-SB-Pd(II) formed from chitosan were examined in five consecutive cycles, which showed no appreciable decrease in activity. Furthermore, a reasonably trifunctional complex structure was proposed. The present bio-based system offers a promising approach in utilizing such biopolymers in organic transformations.


Asunto(s)
Quitosano/química , Paladio/química , Catálisis , Bases de Schiff/química , Espectroscopía Infrarroja por Transformada de Fourier
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