Cancer and bacterial infections rank among the most significant global health threats. accounting for roughly 25 million fatalities each year. This statistic underscores the urgent necessity for developing novel drugs, enhancing current treatments, and implementing systems that boost their bioavailability to achieve superior therapeutic outcomes.
View Article and Find Full Text PDFThe use of natural-origin biomaterials in bioengineering has led to innovative approaches in agroforestry. Bacterial cellulose (BC), sharing the same chemical formula as plant-origin cellulose (PC), exhibits significantly different biochemical properties, including a high degree of crystallinity and superior water retention capacity. Previous research showed that natural-origin glucose-based chitin enhanced plant growth in both herbaceous and non-herbaceous plants.
View Article and Find Full Text PDFIn this study, water-soluble chitosan salts (chitosan amine sulfopropyl salts) were prepared from chitosan samples with different molecular weights and deacetylation degrees. These soluble-in-water polymer salts allowed us to produce, in an eco-friendly and facile method, silver nanoparticles (AgNPs) with better control on size and polydispersity, even at large silver concentrations than their corresponding chitosan sample. Chitosan salt-based materials (films and scaffolds) were analyzed in terms of antibacterial properties against Staphylococcus aureus ATCC23915 or Pseudomonas aeruginosa ATCC 27853.
View Article and Find Full Text PDFBrain-derived neurotrophic factor (BDNF) regulates dendritic branching and dendritic spine morphology, as well as synaptic plasticity and long-term potentiation. Consequently, BDNF deficiency has been associated with some neurological disorders such as Alzheimer's, Parkinson's or Huntington's diseases. In contrast, elevated BDNF levels correlate with recovery after traumatic central nervous system (CNS) injuries.
View Article and Find Full Text PDFChitin and chitosan demand is growing very fast due to interest from industries such as pharmaceutical, cosmetic, agricultural and others. New sources for chitin and chitosan isolation are being extensively searched to fulfil this demand. In this paper, a Baltic benthic crustacean, is evaluated as a source for chitin and chitosan isolation.
View Article and Find Full Text PDFMethotrexate (MTX) administration is the gold standard treatment for rheumatoid arthritis (RA), but its effects are limited to preventing the progression of the disease. Therefore, effective regenerative therapies for damaged tissues are still to be developed. In this regard, MTX complexes of general molecular formula M(MTX)·xHO, where M = Sr, Zn, or Mg, were synthesized and physicochemically characterized by TGA, XRD, NMR, ATR-FTIR, and EDAX spectroscopies.
View Article and Find Full Text PDFIn this work, two chitosan samples from cuttlebone and squid pen are produced and characterized. We studied the formation of thermoresponsive hydrogels with β-glycerol phosphate and found proper formulations that form the hydrogels at 37 °C. Gel formation depended on the chitosan source being possible to produce the thermoresponsive hydrogels at chitosan concentration of 1% with cuttlebone chitosan but 1.
View Article and Find Full Text PDFChitin and its deacetylated derivative chitosan are amino polysaccharides of great interest due to their biological and technological properties [...
View Article and Find Full Text PDFChitosan has garnered much interest due to its properties and possible applications. Every year the number of publications and patents based on this polymer increase. Chitosan exhibits poor solubility in neutral and basic media, limiting its use in such conditions.
View Article and Find Full Text PDFThe purpose of this study was to develop and characterize chitosan (Ch)-based films incorporated with varying molecular weight (Mw) and acetylation degree (AD) chitosan-depolymerization-products (CDP), to be applied as drug delivery materials. As compared to Ch-film, optical and antioxidant potentials of Ch/CDP-based films were improved, particularly using low Mw and AD-CDP. Whereas, films water resistance, mechanical and antibacterial properties increased as CDP-Mw increased and AD decreased.
View Article and Find Full Text PDFChitosan sulfates have demonstrated the ability to mimic heparan sulfate (HS) function. In this context, it is crucial to understand how the specific structural properties of HS domains determine their functionalities and biological activities. In this study, several HS-mimicking chitosans have been prepared to mimic the structure of HS domains that have proved to be functionally significant in cell processes.
View Article and Find Full Text PDFThe aim of this work was to explore the effect of various molecular weight (Mw) chitosan depolymerization products (CDP) on the silver nanoparticles (AgNPs) and chitosan/AgNPs blend films production. Produced AgNPs, stable during 30 days in a colloïdal form, were characterized in terms of UV-vis, transmission electron microscopy (TEM), dynamic light scattering (DLS) and fourier transform infrared spectroscopy (FTIR) analyses. AgNPs displayed interesting antibacterial and antioxidant properties that were affected by the physicochemical properties of used chitosans.
View Article and Find Full Text PDFThis study reports the enzymatic depolymerization of chitosan by the chitosanolytic preparation of Bacillus licheniformis GA11. For this purpose, chitosanase production and biochemical characterization of the crude enzyme preparation from GA11 were firstly investigated. The highest chitosanase production was obtained in a culture medium containing 50.
View Article and Find Full Text PDFIn this study, a digestive chitosanase from blue crab (Portunus segnis) viscera was extracted, characterized and applied. The crude chitosanase showed optimum activity at pH 4.0 and 60 °C and retained >80% of its activity over a pH range from 3.
View Article and Find Full Text PDFSilver nanoparticles (AgNPs) are of great interest due to their antimicrobial, optical and catalytical properties. Green synthesis of AgNPs is fundamental for some applications such as biomedicine and catalysis. Natural polymers, such as chitosan, have been proposed as reducing and stabilizing agents in the green synthesis of AgNPs.
View Article and Find Full Text PDFThe aim of this paper is to study the catalytic behaviour of silver nanoparticles (AgNps) produced using low molecular weight chitosan (LMWC) samples depolymerized by an enzymatic method, using either lysozyme or chitosanase. The ability of four sets of silver nanoparticles to reduce Toluidine Blue (TBO) was used as test reaction, and the effect of both catalyst concentration and reaction temperature on the effectiveness of the catalytic reduction was assessed. Generally speaking, AgNps produced through chitosan depolymerization with lysozyme showed better performance than those ones produced using chitosanase.
View Article and Find Full Text PDFThe conductive and diffusional behavior of electrolytes in media with different dielectric and viscoelastic properties is investigated. A revised model to separate the contribution of dissociated and nondissociated species to the diffusion coefficients determined with NMR is proposed. Impedance spectroscopy is used to measure the ionic conductivity of lithium salts in aqueous medium, ionic liquids in aprotic solvents, and hydrogel polyelectrolytes.
View Article and Find Full Text PDFDespite the relevant biological functions of heparan sulfate (HS) glycosaminoglycans, their limited availability and the chemical heterogeneity from natural sources hamper their use for biomedical applications. Chitosan sulfates (ChS) exhibit structural similarity to HSs and may mimic their biological functions. We prepared a variety of ChS with different degree of sulfation to evaluate their ability to mimic HS in protein binding and to promote neural cell division and differentiation.
View Article and Find Full Text PDFMarine resources are well recognized for their biologically active substances with great potential applications in the cosmeceutical industry. Among the different compounds with a marine origin, chitin and its deacetylated derivative-chitosan-are of great interest to the cosmeceutical industry due to their unique biological and technological properties. In this review, we explore the different functional roles of chitosan as a skin care and hair care ingredient, as an oral hygiene agent and as a carrier for active compounds, among others.
View Article and Find Full Text PDFVenlafaxine controlled drug delivery systems using different matrixes have been tested to reduce undesirable side effects in the treatment of depression. The legal status of chitosan (Cs) in Pharmacy has dramatically improved after its acceptance as excipient in several and, therefore, there is great interest in pharmaceutical formulations based on this polymer. In this paper, chitosan microcapsules cross-linked with sodium tripolyphosphate (TPP) for oral delivery of venlafaxine were formulated using the spray drying technique.
View Article and Find Full Text PDFCalcium phosphate chitosan-based composites have gained much interest in recent years for biomedical purposes. In this paper, three-dimensional calcium phosphate chitosan-based composites with different mineral contents were produced using a green method called ice segregation induced self-assembly (ISISA). In this methodology, ice crystals were used as a template to produce porous structures from an aqueous solution of chitosan (CS) and hydroxyapatite (Hap) also containing acetic acid (pH = 4.
View Article and Find Full Text PDFChitin is the second most abundant biopolymer in nature after cellulose, and it forms an integral part of insect exoskeletons, crustacean shells, krill and the cell walls of fungal spores, where it is present as a high-molecular-weight molecule. In this study, we showed that a chitin oligosaccharide of lower molecular weight (tetramer) induced genes in that are principally related to vegetative growth, development and carbon and nitrogen metabolism. Based on plant responses to this chitin tetramer, a low-molecular-weight chitin mix (CHL) enriched to 92% with dimers (2mer), trimers (3mer) and tetramers (4mer) was produced for potential use in biotechnological processes.
View Article and Find Full Text PDFThree types of chitosan-based films have been prepared and evaluated: a non-modified chitosan film bearing cationizable aliphatic amines and two films made of N-sulfopropyl chitosan derivatives bearing both aliphatic amines and negative sulfonate groups at different ratios. Cell adhesion and proliferation on chitosan films of C2C12 pre-myoblastic cells and B16 cells as tumoral model have been tested. A differential cell behavior has been observed on chitosan films due to their different surface modification.
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