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1.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928474

RESUMO

Chitosan is a natural polymer with numerous biomedical applications. The cellular activity of chitosan has been studied in various types of cancer, including melanoma, and indicates that these molecules can open new perspectives on antiproliferative action and anticancer therapy. This study analyzes how different chitosan conformations, such as α-chitosan (CH) or ß-oligochitosan (CO), with various degrees of deacetylation (DDA) and molar mass (MM), both in different concentrations and in CH-CO mixtures, influence the cellular processes of SK-MEL-28 melanocytes, to estimate the reactivity of these cells to the applied treatments. The in vitro evaluation was carried out, aiming at the cellular metabolism (MTT assay), cellular morphology, and chitinase-like glycoprotein YKL-40 expression. The in vitro effect of the CH-CO mixture application on melanocytes is obvious at low concentrations of α-chitosan/ß-oligochitosan (1:2 ratio), with the cell's response supporting the hypothesis that ß-oligo-chitosan amplifies the effect. This oligochitosan mixture, favored by the ß conformation and its small size, penetrates faster into the cells, being more reactive when interacting with some cellular components. Morphological effects expressed by the loss of cell adhesion and the depletion of YKL-40 synthesis are significant responses of melanocytes. ß-oligochitosan (1.5 kDa) induces an extension of cytophysiological effects and limits the cell viability compared to α-chitosan (400-900 kDa). Statistical analysis using multivariate techniques showed differences between the CH samples and CH-CO mixtures.


Assuntos
Quitina , Proteína 1 Semelhante à Quitinase-3 , Quitosana , Melanócitos , Oligossacarídeos , Quitosana/química , Quitosana/farmacologia , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Humanos , Quitina/análogos & derivados , Quitina/farmacologia , Quitina/química , Oligossacarídeos/farmacologia , Proteína 1 Semelhante à Quitinase-3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Melanoma/patologia
2.
Int J Biol Macromol ; 274(Pt 1): 133378, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38914401

RESUMO

Deep-eutectic solvents (DES) have emerged as promising candidates for preparing nanocomposites. In this study, a DES-based graphitic carbon nitride (g-C3N4)/ZnO/Chitosan (Ch) nanocomposite was synthesized to remove malachite green (MG) dye from water. The DES was prepared by mixing and heating citric acid as a hydrogen bond acceptor and lactic acid as a hydrogen bond donor. This is the first report of the removal of MG using DES-based nanocomposites. Experiments on kinetics and isothermal adsorption were conducted to systematically explore the adsorption performances of nanocomposite toward dye. At 25 °C, the highest adsorption performance was obtained with alkaline media (>90 % removal). The greatest adsorption capacity (qm) was 59.52 mg g-1 at conditions (30 mg L-1 MG solution, pH 9, 3 mg nanocomposite per 10 mL of MG solution, 25 °C, 150 rpm, and 150 min) based on the calculation from the best-fitting isotherm model (Langmuir). The adsorption process was most appropriately kinetically described by the PSO model. The Monte Carlo (MC) and molecular dynamic (MC) results are correlated with experimental findings to validate the theoretical predictions and enhance the overall understanding of the adsorption process. Electronic structure calculations reveal the nature of interactions, including hydrogen bonding and electrostatic forces, between the nanocomposite and MG molecules.


Assuntos
Quitosana , Grafite , Simulação de Dinâmica Molecular , Método de Monte Carlo , Nanocompostos , Corantes de Rosanilina , Óxido de Zinco , Quitosana/química , Nanocompostos/química , Corantes de Rosanilina/química , Corantes de Rosanilina/isolamento & purificação , Adsorção , Grafite/química , Óxido de Zinco/química , Cinética , Solventes Eutéticos Profundos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Compostos de Nitrogênio/química , Concentração de Íons de Hidrogênio
3.
J Environ Manage ; 360: 121210, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781878

RESUMO

The food industry requires new production models that include more environmentally friendly waste management practices, considering that the environmental loads of solid waste and wastewater associated with this sector cause damage to the receiving ecosystems. The approach considered in this study focuses on the design and environmental assessment of an enzymatic process for the valorization of ferulic acid present in the effluent of a corn tortilla plant. The ferulic acid can be immobilized on chitosan so that the ferulic acid grafted chitosan can be used as a bioactive film with enhanced antioxidant properties with potential applications in the biotechnology sector. Its real projection approach requires the evaluation of its environmental and economic performance, trying to identify its benefits and potential in the value chain, using the Techno-Economic Analysis (TEA) as a phase for the conceptual design of the process and the Life Cycle Assessment (LCA) methodology for the environmental evaluation. It should be noted that the TEA indicators are promising, since the values of the financial indicators obtained are representative of the economic profitability, which makes the ferulic acid valorization a viable process. In terms of the environmental impact of the process, the buffer dose and the chitosan production process are identified as the main critical points. This double benefit in environmental and economic terms shows that the valorization of ferulic acid for chitosan functionalization is a promising alternative to improve the sustainability performance of corn processing.


Assuntos
Quitosana , Ácidos Cumáricos , Zea mays , Quitosana/química , Ácidos Cumáricos/química , Polímeros/química , Gerenciamento de Resíduos/métodos
4.
Methods Mol Biol ; 2775: 329-347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758327

RESUMO

The cell wall of the fungal pathogens Cryptococcus neoformans and C. gattii is critical for cell wall integrity and signaling external threats to the cell, allowing it to adapt and grow in a variety of changing environments. Chitin is a polysaccharide found in the cell walls of fungi that is considered to be essential for fungal survival. Chitosan is a polysaccharide derived from chitin via deacetylation that is also essential for cryptococcal cell wall integrity, fungal pathogenicity, and virulence. Cryptococcus has evolved mechanisms to regulate the amount of chitin and chitosan during growth under laboratory conditions or during mammalian infection. Therefore, levels of chitin and chitosan have been useful phenotypes to define mutant Cryptococcus strains. As a result, we have developed and/or refined various qualitative and quantitative methods for measuring chitin and chitosan. These techniques include those that use fluorescent probes that are known to bind to chitin (e.g., calcofluor white and wheat germ agglutinin), as well as those that preferentially bind to chitosan (e.g., eosin Y and cibacron brilliant red 3B-A). Techniques that enhance the localization and quantification of chitin and chitosan in the cell wall include (i) fluorescence microscopy, (ii) flow cytometry, (iii) and spectrofluorometry. We have also modified two highly selective biochemical methods to measure cellular chitin and chitosan content: the Morgan-Elson and the 3-methyl-2-benzothiazolone hydrazine hydrochloride (MBTH) assays, respectively.


Assuntos
Parede Celular , Quitina , Quitosana , Quitina/metabolismo , Quitina/química , Quitina/análise , Quitosana/química , Quitosana/metabolismo , Parede Celular/metabolismo , Parede Celular/química , Cryptococcus neoformans/metabolismo , Corantes Fluorescentes/química , Cryptococcus/metabolismo , Microscopia de Fluorescência/métodos
5.
BMC Biotechnol ; 24(1): 27, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725019

RESUMO

Cyanobacteria represent a rich resource of a wide array of unique bioactive compounds that are proving to be potent sources of anticancer drugs. Selenium nanoparticles (SeNPs) have shown an increasing potential as major therapeutic platforms and led to the production of higher levels of ROS that can present desirable anticancer properties. Chitosan-SeNPs have also presented antitumor properties against hepatic cancer cell lines, especially the Cht-NP (Chitosan-NPs), promoting ROS generation and mitochondria dysfunction. It is proposed that magnetic fields can add new dimensions to nanoparticle applications. Hence, in this study, the biosynthesis of SeNPs using Alborzia kermanshahica and chitosan (CS) as stabilizers has been developed. The SeNPs synthesis was performed at different cyanobacterial cultivation conditions, including control (without magnetic field) and magnetic fields of 30 mT and 60 mT. The SeNPs were characterized by uv-visible spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), Dynamic light scattering (DLS), zeta potential, and TEM. In addition, the antibacterial activity, inhibition of bacterial growth, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC), as well as the antifungal activity and cytotoxicity of SeNPs, were performed. The results of uv-visible spectrometry, DLS, and zeta potential showed that 60 mT had the highest value regarding the adsorption, size, and stabilization in compared to the control. FTIR spectroscopy results showed consistent spectra, but the increased intensity of peaks indicates an increase in bond number after exposure to 30 mT and 60 mT. The results of the antibacterial activity and the inhibition zone diameter of synthesized nanoparticles showed that Staphylococcus aureus was more sensitive to nanoparticles produced under 60 mT. Se-NPs produced by Alborzia kermanshahica cultured under a 60 mT magnetic field exhibit potent antimicrobial and anticancer properties, making them a promising natural agent for use in the pharmaceutical and biomedical industries.


Assuntos
Quitosana , Campos Magnéticos , Selênio , Selênio/química , Selênio/farmacologia , Quitosana/química , Quitosana/farmacologia , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/biossíntese , Testes de Sensibilidade Microbiana , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo , Antineoplásicos/química , Nanopartículas Metálicas/química
6.
Int J Biol Macromol ; 270(Pt 1): 132269, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38744363

RESUMO

Burn wounds (BWs) cause impairment of native skin tissue and may cause significant microbial infections that demand immediate care. Curcumin (Cur) and quercetin (Que) exhibit antimicrobial, hemocompatibility, ROS-scavenging, and anti-inflammatory properties. However, its instability, water insolubility, and low biological fluid absorption render it challenging to sustain local Cur and Que doses at the wound site. Therefore, to combat these limitations, we employed blow-spinning and freeze-drying to develop a multi-layered, Cur/Que-loaded gelatin/chitosan/PCL (GCP-Q/C) nanofibroporous (NFP) matrix. Morphological analysis of the NFP-matrix using SEM revealed a well-formed multi-layered structure. The FTIR and XRD plots demonstrated dual-bioactive incorporation and scaffold polymer interaction. Additionally, the GCP-Q/C matrix displayed high porosity (82.7 ± 2.07 %), adequate pore size (∼121 µm), enhanced water-uptake ability (∼675 % within 24 h), and satisfactory biodegradation. The scaffolds with bioactives had a long-term release, increased antioxidant activity, and were more effective against gram-positive (S. aureus) and gram-negative (E. coli) bacteria than the unloaded scaffolds. The in vitro findings of GCP-Q/C scaffolds showed promoted L929 cell growth and hemocompatibility. Additionally, an in vivo full-thickness BW investigation found that an implanted GCP-Q/C matrix stimulates rapid recuperation and tissue regeneration. In accordance with the findings, the Gel/Ch/PCL-Que/Cur NFP-matrix could represent an effective wound-healing dressing for BWs.


Assuntos
Queimaduras , Curcumina , Nanofibras , Quercetina , Cicatrização , Curcumina/farmacologia , Curcumina/química , Cicatrização/efeitos dos fármacos , Quercetina/farmacologia , Quercetina/química , Animais , Porosidade , Nanofibras/química , Queimaduras/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/química , Ratos , Quitosana/química , Antioxidantes/farmacologia , Antioxidantes/química , Gelatina/química , Camundongos , Alicerces Teciduais/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Liberação Controlada de Fármacos
7.
Burns ; 50(6): 1586-1596, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38641499

RESUMO

BACKGROUND: The purpose of dermal substitutes is to mimic the basic properties of the extracellular matrix of human skin. The application of dermal substitutes to the defect reduces the formation of hypertrophic scars and improves the scar quality. This study aims to develop an original dermal substitute enriched with stable fibroblast growth factor 2 (FGF2-STAB®) and test it in an animal model. METHODS: Dermal substitutes based on collagen/chitosan scaffolds or collagen/chitosan scaffolds with nanofibrous layer were prepared and enriched with FGF2-STAB® at concentrations of 0, 0.1, 1.0, and 10.0 µg ‧ cm-2. The performance of these dermal substitutes was tested in vivo on artificially formed skin defects in female swine. The outcomes were evaluated using cutometry at 3 and 6 months. In addition, visual appearance was assessed based on photos of the scars at 1-month, 3-month and 6-month follow-ups using Yeong scale and Visual Analog Scale. RESULTS: The dermal substitute was fully integrated into all defects and all wounds healed successfully. FGF2-STAB®-enriched matrices yielded better results in cutometry compared to scaffolds without FGF2. Visual evaluation at 1, 3, and 6 months follow-ups detected no significant differences among groups. The FGF2-STAB® effectiveness in improving the elasticity of scar tissues was confirmed in the swine model. This effect was independently observed in the scaffolds with nanofibres as well as in the scaffolds without nanofibres. CONCLUSION: The formation of scars with the best elasticity was exhibited by addition 1.0 µg ‧ cm-2of FGF2-STAB® into the scaffolds, although it had no significant effect on visual appearance at longer follow-ups. This study creates the basis for further translational studies of the developed product and its progression into the clinical phase of the research.


Assuntos
Quitosana , Elasticidade , Fator 2 de Crescimento de Fibroblastos , Pele Artificial , Animais , Suínos , Feminino , Alicerces Teciduais , Colágeno , Viscosidade , Cicatriz Hipertrófica , Queimaduras , Cicatrização/efeitos dos fármacos , Nanofibras/uso terapêutico , Modelos Animais de Doenças , Pele
8.
Int Wound J ; 21(5): e14878, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38682897

RESUMO

The primary objective of this study was to develop a carboxymethyl cellulose (CMC) and carboxymethyl chitosan (CMCS) hydrogel containing ethylene diamine tetra acetic acid (EDTA) as the materials for wound healing. CMC and CMCS solutions were prepared with a concentration of 4% (w/v). These solutions were made using normal saline serum with a concentration of 0.5% (v/v). Additionally, EDTA with the concentrations of 0.01%, 0.05%, 0.1%, 0.5%, 1%, and 2% (w/v) was included in the prepared polymer solution. The analysis of the hydrogels revealed that they possess porous structures with interconnected pores, with average in size 88.71 ± 5.93 µm. The hydrogels exhibited a swelling capacity of up to 60% of their initial weight within 24 h, as indicated by the weight loss and swelling measurements. The antibacterial experiments showed that the formulated CMC/CMCS/EDTA 0.5% hydrogel inhibited the growth of Staphylococcus aureus and Pseudomonas aeruginosa. Moreover, the produced hydrogels were haemocompatible and biocompatible. At the last stage, the evaluation of wound healing in the animal model demonstrated that the use of the produced hydrogels significantly improved the process of wound healing. Finally, the findings substantiated the effectiveness of the formulated hydrogels as the materials for promoting wound healing and antibacterial agents.


Assuntos
Biofilmes , Carboximetilcelulose Sódica , Quitosana , Quitosana/análogos & derivados , Ácido Edético , Hidrogéis , Pseudomonas aeruginosa , Staphylococcus aureus , Cicatrização , Animais , Quitosana/farmacologia , Ratos , Ácido Edético/farmacologia , Ácido Edético/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Carboximetilcelulose Sódica/farmacologia , Cicatrização/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Hidrogéis/farmacologia , Modelos Animais de Doenças , Masculino , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ratos Wistar , Infecções Estafilocócicas/tratamento farmacológico , Infecção dos Ferimentos/tratamento farmacológico , Infecções por Pseudomonas/tratamento farmacológico
9.
Int J Biol Macromol ; 269(Pt 1): 131897, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677671

RESUMO

Chitosan (Ch) is a linear biodegradable natural carbohydrate polymer and the most appealing biopolymer, such as low-cost biodegradability, biocompatibility, hydrophilicity, and non-toxicity. In this case, Ch was utilized to synthesize AgCoFe2O4@Ch/Activated Carbon (AC) by the modified microwave-assisted co-precipitation method. The physical and chemical structure of magnetic nanocomposites was analyzed and characterized by Field Emission Scanning Electron Microscope (FESEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Energy Dispersive Spectroscopy (EDS), Diffuse Reflection Spectroscopy (DRS), Value stream mapping (VSM), Fourier transform spectroscopy (FTIR) and BET. The effects of various parameters on the removal of dye (Acid Red18), including catalyst dose, dye concentration, pH, and time were studied. Results showed that the highest removal efficiencies were 96.68 % and 84 % for the synthetic sample and actual wastewater, respectively, in optimal conditions (pH: 3, the initial dye concentration: 10 mgL-1, the catalyst dose: 0.14 gL-1, time: 50 min). Mineralization, according to the COD analysis, was 89.56 %. Photocatalytic degradation kinetics of Acid Red 18 followed pseudo-first order and Langmuir-Hinshelwood with constants of kc = 0.12 mg L-1 min-1 and KL-H = 0.115 Lmg-1. Synthesized photocatalytic AgCoFe2O4@Ch/AC showed high stability and after five recycling cycles was able to remove the pollutant with an efficiency of 85.6 %. So, the synthesized heterogenous magnetic nanocatalyst AgCoFe2O4@Ch/AC was easily recycled from aqueous solutions and it can be used in the removal of dyes from industries with high efficiency.


Assuntos
Poluentes Químicos da Água , Catálise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Nanocompostos/química , Quitosana/química , Purificação da Água/métodos , Compostos Azo/química , Compostos Azo/isolamento & purificação , Reciclagem/métodos , Concentração de Íons de Hidrogênio , Águas Residuárias/química , Fotólise , Nanopartículas de Magnetita/química , Cinética , Compostos Férricos/química , Carbono/química
10.
Food Chem ; 451: 139447, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38688097

RESUMO

An eco-friendly hydrothermal method synthesized VS2 nanosheets. Several spectroscopic and microscopic approaches (TEM) were used to characterize the produced VS2 nanosheet microstructure. VS2, Chitosan, and nanocomposite were used to immobilize watermelon (Citrullus lanatus) urease. Optimization using the Response Surface Methodology and the Box-Behnken design yielded immobilization efficiencies of 65.23 %, 72.52 %, and 87.68 % for chitosan, VS2, and nanocomposite, respectively. The analysis of variance confirmed the mathematical model's validity, enabling additional research. AFM, SEM, FTIR, Fluorescence microscopy, and Cary Eclipse Fluorescence Spectrometer showed urease conjugation to the matrix. During and after immobilization, FTIR spectra showed a dynamic connectivity of chemical processes and bonding. The nanocomposite outperformed VS2 and chitosan in pH and temperature. Chitosan and VS2-immobilized urease were more thermally stable than soluble urease, but the nanocomposite-urease system was even more resilient. The nanocomposite retained 60 % of its residual activity after three months of storage. It retains 91.8 % of its initial activity after 12 reuse cycles. Nanocomposite-immobilized urease measured milk urea at 23.62 mg/dl. This result was compared favorably to the gold standard p-dimethylaminobenzaldehyde spectrophotometric result of 20 mg/dl. The linear range is 5 to 70 mg/dl, with a LOD of 1.07 (±0.05) mg/dl and SD of less than 5 %. The nanocomposite's ksel coefficient for interferents was exceptionally low (ksel < 0.07), indicating urea detection sensitivity. Watermelon urease is suitable for dairy sector applications due to its availability, immobilization on nanocomposite, and reuse.


Assuntos
Quitosana , Citrullus , Enzimas Imobilizadas , Leite , Nanocompostos , Urease , Citrullus/química , Citrullus/enzimologia , Urease/química , Urease/metabolismo , Quitosana/química , Enzimas Imobilizadas/química , Nanocompostos/química , Leite/química , Animais , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Ureia/química
11.
Int J Pharm ; 654: 123999, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38490403

RESUMO

Colorectal cancer (CC) is one of the most predominant malignancies in the world, with the current treatment regimen consisting of surgery, radiation therapy, and chemotherapy. Chemotherapeutic drugs, such as 5-fluorouracil (5-FU), have gained popularity as first-line antineoplastic agents against CC but have several drawbacks, including variable absorption through the gastrointestinal tract, inconsistent liver metabolism, short half-life, toxicological reactions in several organ systems, and others. Therefore, herein, we develop chitosan-coated zinc-substituted cobalt ferrite nanoparticles (CZCFNPs) for the pH-sensitive (triggered by chitosan degradation within acidic organelles of cells) and sustained delivery of 5-FU in CC cells in vitro. Additionally, the developed nanoplatform served as an excellent exogenous optical coherence tomography (OCT) contrast agent, enabling a significant improvement in the OCT image contrast in a CC tissue phantom model with a biomimetic microvasculature. Further, this study opens up new possibilities for using OCT for the non-invasive monitoring and/or optimization of magnetic targeting capabilities, as well as real-time tracking of magnetic nanoparticle-based therapeutic platforms for biomedical applications. Overall, the current study demonstrates the development of a CZCFNP-based theranostic platform capable of serving as a reliable drug delivery system as well as a superior OCT exogenous contrast agent for tissue imaging.


Assuntos
Quitosana , Cobalto , Compostos Férricos , Nanopartículas , Medicina de Precisão , Meios de Contraste , Zinco , Tomografia de Coerência Óptica , Sistemas de Liberação de Medicamentos , Fluoruracila/uso terapêutico , Concentração de Íons de Hidrogênio , Nanomedicina Teranóstica
12.
Sci Rep ; 14(1): 7381, 2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548964

RESUMO

The aim of the present work is to biosynthesize Chitosan nanoparticles (CTNp) using tea (Camellia sinensis) extract, with potent antimicrobial properties towards phytopathogens of rice. Preliminary chemical analysis of the extract showed that they contain carbohydrate as major compound and uronic acid indicating the nature of acidic polysaccharide. The structure of the isolated polysaccharide was analyzed through FTIR and 1H NMR. The CTNp was prepared by the addition of isolated tea polysaccharides to chitosan solution. The structure and size of the CTNp was determined through FTIR and DLS analyses. The surface morphology and size of the CTNp was analysed by SEM and HRTEM. The crystalinity nature of the synthesized nanoparticle was identified by XRD analysis. The CTNp exhibited the antimicrobial properties against the most devastating pathogens of rice viz., Pyricularia grisea, Xanthomonas oryzae under in vitro condition. CTNp also suppressed the blast and blight disease of rice under the detached leaf assay. These results suggest that the biosynthesized CTNp can be used to control the most devastating pathogens of rice.


Assuntos
Quitosana , Nanopartículas , Oryza , Quitosana/farmacologia , Nanopartículas/química , Chá , Extratos Vegetais/farmacologia
13.
Biomed Mater ; 19(3)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38537280

RESUMO

The biomaterials based on chitosan andEclipta prostrataL. extract have been prepared by microemulsion method and solution method (with and without sodium tripolyphosphate (STPP) as a cross-linking agent). The main component inEclipta prostrataL. extract is flavonoid groups. The structure of the chitosan/extract biomaterials was studied by infrared spectroscopy. The chitosan/extract biomaterial using STPP cross-linker appeared an absorption band at 1152 cm-1attributed to the vibrations of C-O-P bonds, which proved that chitosan has crosslinked with STPP. The morphology of the biomaterials was investigated by the dynamic light scattering technique and field emission scanning electron microscopy. The obtained results showed that the particle size of the chitosan/extract biomaterials prepared by microemulsion method and solution method with STPP ranged from 68.06 nm to 1484 nm, with an average particle size of 304.9-1019 nm. The microemulsion method produced biomaterials with much smaller average particle size than the solution method using cross-linkers. The hemostatic ability of the biomaterials was better than that of the control sample based on the time of blood clotting formation and glomerular aggregation ability. The sample with the ratio ofE. prostrataL. extract: chitosan of 1:30 had the lowest hemostasis time (6 min 46 s) and its glomerular aggregation rate after 5 min was 13.05%. This indicated that the biomaterials based on chitosan andE. prostrataL. extract are promising for application in biomedicine as hemostatic materials.


Assuntos
Quitosana , Hemostáticos , Quitosana/química , Materiais Biocompatíveis/química , Hemostasia , Coagulação Sanguínea
14.
Microbiol Spectr ; 12(4): e0363923, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38411050

RESUMO

Chitosan oligosaccharide (COS) is a new type of marine functional oligosaccharide with biological activities such as regulating intestinal microflora and improving intestinal immunity. In this study, female Drosophila melanogaster was used as a model organism to evaluate the effect of COS on intestinal injury by H2O2 induction, and its mechanism was explored through the analysis of intestinal homeostasis. The results showed that 0.25% of COS could effectively prolong the lifespan of stressed female D. melanogaster by increasing its antioxidant capacity and maintaining intestinal homeostasis, which included protecting the mechanical barrier, promoting the chemical barrier, and regulating the biological barrier by affecting its autophagy and the antioxidant signaling pathway. Additionally, the protective effect of COS on the intestinal barrier and homeostasis of D. melanogaster under oxidative stress status is directly related to its regulation of the intestinal microflora, which could decrease excessive autophagy and activate the antioxidant system to promote health. IMPORTANCE: The epithelial barrier plays an important role in the organism's health. Chitosan oligosaccharide (COS), a new potential prebiotic, exhibits excellent antioxidant capacity and anti-inflammatory effects. Our study elucidated the protective mechanisms of COS on the intestinal barrier of Drosophila melanogaster under oxidative stress, which could provide new insights into COS application in various industries, such as food, agriculture, and medicine.


Assuntos
Quitosana , Microbioma Gastrointestinal , Animais , Feminino , Drosophila melanogaster , Antioxidantes/metabolismo , Quitosana/farmacologia , Promoção da Saúde , Peróxido de Hidrogênio , Oligossacarídeos/farmacologia
15.
Int J Biol Macromol ; 261(Pt 1): 129816, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290626

RESUMO

To improve the antioxidant activity, sulfhydryl groups (-SH) were introduced into chitosan. Acylated chitosan derivatives, chitosan cationic salt derivatives, hydroxypropyl trimethylammonium chloride chitosan quaternary ammonium salt (HACC) derivatives and N,N,N-trimethyl chitosan iodine (TMC) derivatives were obtained. The chitosan derivatives were characterized by FTIR and 1H NMR to confirm the successful synthesis. Ellman's reagent was used to determine that the compound contained free sulfhydryl groups. The water solubility and thermal stability of chitosan and derivatives were evaluated. The antioxidant activities of the derivatives were verified, including DPPH radical scavenging activity, superoxide anion radical scavenging activity and reducing power activity. The novel chitosan derivatives showed excellent antioxidant activities. Toxicity assay used L929 cells proved that the derivatives had no significant toxic. The results showed that the chitosan derivatives bearing sulfhydryl groups described in this paper has a certain antioxidant effect, which provides a practical approach for further study of chitosan.


Assuntos
Antioxidantes , Quitosana , Antioxidantes/farmacologia , Antioxidantes/química , Quitosana/química , Espectroscopia de Ressonância Magnética , Compostos de Amônio Quaternário/farmacologia , Compostos de Amônio Quaternário/química , Solubilidade
16.
Anticancer Agents Med Chem ; 24(7): 533-543, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38243949

RESUMO

AIMS AND BACKGROUND: Echis carinatus venom is a toxic substance naturally produced by special glands in this snake species. Alongside various toxic properties, this venom has been used for its therapeutic effects, which are applicable in treating various cancers (liver, breast, etc.). OBJECTIVE: Nanotechnology-based drug delivery systems are suitable for protecting Echis carinatus venom against destruction and unwanted absorption. They can manage its controlled transfer and absorption, significantly reducing side effects. METHODS: In the present study, chitosan nanoparticles were prepared using the ionotropic gelation method with emulsion cross-linking. The venom's encapsulation efficiency, loading capacity, and release rate were calculated at certain time points. Moreover, the nanoparticles' optimal formulation and cytotoxic effects were determined using the MTT assay. RESULTS: The optimized nanoparticle formulation increases cell death induction in various cancerous cell lines. Moreover, chitosan nanoparticles loaded with Echis carinatus venom had a significant rate of cytotoxicity against cancer cells. CONCLUSION: It is proposed that this formulation may act as a suitable candidate for more extensive assessments of cancer treatment using nanotechnology-based drug delivery systems.


Assuntos
Antineoplásicos , Sobrevivência Celular , Quitosana , Ensaios de Seleção de Medicamentos Antitumorais , Nanopartículas , Quitosana/química , Quitosana/farmacologia , Humanos , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Venenos de Víboras/química , Venenos de Víboras/farmacologia , Proliferação de Células/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Relação Estrutura-Atividade , Tamanho da Partícula , Estrutura Molecular , Viperidae , Linhagem Celular Tumoral , Echis , Serpentes Peçonhentas , Polifosfatos
17.
Int J Biol Macromol ; 254(Pt 3): 128038, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37963501

RESUMO

The present work deals with the eco-friendly preparation of highly degradable food packaging films consisting of O-CMC (O-Carboxymethyl Chitosan) and pectin, incorporated with neem (Azadirachta indica) leaves powder and extract. This study aimed to investigate the tensile properties, antimicrobial activity, biodegradability, and thermal behavior of the composite films. The results of tensile strength and elongation at break, showed that the incorporation of neem leaves powder improved the tensile properties (7.11 MPa) of the composite films compared to the neat O-CMC and pectin films (3.02 MPa). The antimicrobial activity of the films was evaluated against a panel of microorganisms including both gram-positive and gram-negative bacteria as well as fungi. The composite films exhibited excellent antimicrobial activity with a zone of inhibition (12-17.6 mm) against the tested microorganisms. The opacity of the composite films ranges from 1.14 to 4.40 mm-1 and the addition of fiber causes a decrease in opacity value. Biodegradability studies were conducted by Soil burial method and the films demonstrated complete biodegradability within 75 days. The results of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) of composite films show that they are thermally stable and might be used in food packaging.


Assuntos
Anti-Infecciosos , Azadirachta , Quitosana , Pectinas , Embalagem de Alimentos/métodos , Antibacterianos/farmacologia , Pós , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Quitosana/química
18.
Drug Deliv Transl Res ; 14(4): 895-917, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37843733

RESUMO

Hesperidin (Hsd), a bioactive phytomedicine, experienced an antidiabetic activity versus both Type 1 and Type 2 Diabetes mellitus. However, its intrinsic poor solubility and bioavailability is a key challenging obstacle reflecting its oral delivery. From such perspective, the purpose of the current study was to prepare and evaluate Hsd-loaded sulfobutylether-ß-cyclodextrin/chitosan nanoparticles (Hsd/CD/CS NPs) for improving the hypoglycemic activity of the orally administered Hsd. Hsd was first complexed with sulfobutylether-ß-cyclodextrin (SBE-ß-CD) and the complex (CX) was found to be formed with percent complexation efficiency and percent process efficiency of 50.53 ± 1.46 and 84.52 ± 3.16%, respectively. Also, solid state characterization of the complex ensured the inclusion of Hsd inside the cavity of SBE-ß-CD. Then, Hsd/CD/CS NPs were prepared using the ionic gelation technique. The prepared NPs were fully characterized to select the most promising one (F1) with a homogenous particle size of 455.7 ± 9.04 nm, a positive zeta potential of + 32.28 ± 1.12 mV, and an entrapment efficiency of 77.46 ± 0.39%. The optimal formula (F1) was subjected to further investigation of in vitro release, ex vivo intestinal permeation, stability, cytotoxicity, and in vivo hypoglycemic activity. The results of the release and permeation studies of F1 manifested a modulated pattern between Hsd and CX. The preferential stability of F1 was observed at 4 ± 1 °C. Also, the biocompatibility of F1 with oral epithelial cell line (OEC) was retained up to a concentration of 100 µg/mL. After oral administration of F1, a noteworthy synergistic hypoglycemic effect was recorded with decreased blood glucose level until the end of the experiment. In conclusion, Hsd/CD/CS NPs could be regarded as a hopeful oral delivery system of Hsd with enhanced antidiabetic activity.


Assuntos
Quitosana , Diabetes Mellitus Tipo 2 , Hesperidina , Nanopartículas , beta-Ciclodextrinas , Humanos , Hipoglicemiantes/farmacologia , Portadores de Fármacos
19.
J Biomater Sci Polym Ed ; 35(1): 63-84, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37804323

RESUMO

In the present study, an ionic gelation and ultrasonic approach was performed to produce kojic acid (KA) loaded chitosan(CS)/collagen(CN) nanoparticle(NP) (CSCN-NP) which aimed to increase the dermal delivery and anti-pigmentation effect. To optimize the CSCN-NP the effect of the amount of CN was investigated. The results showed that increasing CN from 0 to 500 mg increased the mean particle size and entrapment efficiency of KA-CSCN-NP from 266.07 ± 9.30 nm to 404.23 ± 9.44 nm and 17.37 ± 2.06% to 82.34 ± 2.16%, respectively. Differential scanning calorimetry confirmed the amorphous form of KA in CSCN-NP, while scanning electron microscopy revealed that the nanoparticles were spherical. There was no chemical interaction between KA and the other components base on attenuated total reflectance-Fourier transform infrared spectroscopy. The skin permeability test showed that KA-CSCN-NP gel delivered more KA to the dermal layers (29.16 ± 1.67% or 537.26 ± 537.26 µg/cm2) and receiver compartment (15.04 ± 1.47% or 277.15 ± 27.22 µg/cm2) compared to KA plain gel. In vitro cytotoxicity assay demonstrated that the improved KA-CSCN-NP was non-toxic. Dermal irritating test on Wistar rats showed that the KA gel was non-irritating. Furthermore, KA-CSCN-NP was found to inhibit melanin formation to a greater extent than free KA and significantly inhibited L-dopa auto-oxidation (94.80 ± 2.41%) compared to pure kojic acid solution (75.28 ± 3.22%). The observations of this study revealed that the produced KA-CSCN-NP might be used as a potential nano-vehicle for KA dermal administration, thereby opening up innovative options for the management of hyper-melanogenesis problems.


Assuntos
Quitosana , Nanopartículas , Ratos , Animais , Quitosana/química , Ratos Wistar , Nanopartículas/química , Colágeno , Tamanho da Partícula
20.
Int J Biol Macromol ; 256(Pt 1): 128291, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029901

RESUMO

This study aims to develop chitosan-bioactive glass (BG) scaffolds for diabetic wound healing, toxicity valuation, and subcutaneous implantation in animals for biocompatibility assessment. The scaffolds were prepared by lyophilization technique. In specific BG without sodium (Na), composited with chitosan for better biological activities. The equipped scaffolds were studied for their physiochemical, biological, in vitro and in vivo performances. The chitosan and chitosan-BG (Na free) scaffolds show reliable biocompatibility, cytocompatibility, anti-oxidant, and tissue regeneration. The biocompatibility, toxicity assessments, and diabetic skin wound healing experiments were examined through in vivo studies using Sprague Dawley rats. The extracted tissue samples were analyzed using hematoxylin-eosin- (H and E) and Masson's trichrome staining. Further, tissue excised after scaffold implantation declared non-toxic, non-allergic, and anti-inflammatory nature of chitosan scaffolds. Moreover, the total ribonucleic acid (RNA) expression levels were measured using reverse transcription-polymerase chain reaction (RT-PCR) for the scaffolds against vascular endothelial growth factor (VEGF), and collagen type one (Col-1) primers. Admirably, the scaffolds achieved the best level of skin wound healing via tissue regeneration by increasing epithetical cell formation and collagen deposition. Thus, the biocompatibility, non-toxicity, anti-inflammatory, and wound healing efficiency proved that the chitosan-BG (Na free) scaffold can be readily substantial for wound healing.


Assuntos
Quitosana , Diabetes Mellitus , Ratos , Animais , Alicerces Teciduais , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ratos Sprague-Dawley , Cicatrização , Colágeno/metabolismo , Anti-Inflamatórios , Modelos Animais
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