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1.
Gene ; 720: 144096, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476405

RESUMO

Biologically active materials and polymeric materials used in tissue engineering have been one of the most attractive research areas in the past decades, especially the use of easily accessible materials from the patients that reduces or eliminates any patient's immune response. In this study, electrospun nanofibrous scaffolds were fabricated by using polyvinyl-alcohol (PVA), chitosan and hydroxyapatite (HA) polymers and platelet-rich plasma (PRP) as a bioactive substance isolated from human blood. Fabricated scaffold's structure and cytotoxicity were evaluated using scanning electron microscope and MTT assays. Scaffolds osteoinductivity was investigated by osteogenic differentiation of the mesenchymal stem cells (MSCs) at the in vitro level and then its osteoconductivity was examined by implanting at the critical-sized rat calvarial defect. The in vitro results showed that scaffolds have a good structure and good biocompatibility. Alkaline phosphatase activity, calcium content and gene expression assays were also demonstrated that their highest amount was detected in MSCs-seeded PVA-chitosan-HA(PRP) scaffold. For this reason, this scaffold alone and along with the MSCs was implanted to the animal defects. The in vivo results demonstrated that in the animals implanted with PVA-chitosan-HA(PRP), the defect was repaired to a good extent, but in those animals that received MSCs-seeded PVA-chitosan-HA(PRP), the defects was almost filled. It can be concluded that, PVA-chitosan-HA(PRP) alone or when stem cells cultured on them, has a great potential to use as an effective bone implant.


Assuntos
Diferenciação Celular , Nanofibras/química , Osteogênese , Plasma Rico em Plaquetas/química , Procedimentos Cirúrgicos Reconstrutivos , Crânio/cirurgia , Animais , Células Cultivadas , Quitosana/química , Durapatita/química , Masculino , Células-Tronco Mesenquimais/citologia , Álcool de Polivinil/química , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual , Tecidos Suporte
2.
J Agric Food Chem ; 67(39): 10880-10890, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31508956

RESUMO

A sustainable biomass-based nanocomposite hydrogel was formulated, characterized, and applied for curcumin delivery. Phytosynthesized zinc oxide nanoparticles (ZnO NPs) employing musk melon (Cucumis melo) seed extract was embedded in the hydrogel matrices and cross-linked using Dialdehyde cellulose prepared from sugarcane (Saccharum officinarum) bagasse (SCB). Nanoparticle incorporation enhanced the hydrogel's swelling degree to 4048% at pH 4.0. Also, an improved tensile strength of 14.1 ± 0.32 MPa was exhibited by the nanocomposite hydrogel compared to 9.79 ± 0.76 MPa for the pure chitosan cellulose hydrogel. A curcumin loading efficiency of 89.68% with around 30% increased loading was exhibited for the nanocomposite hydrogel. A Fickian diffusion-controlled curcumin release mechanism with maximum release at pH 7.4 was obtained. The synergistic effect on the antimicrobial activity was exhibited against Staphylococcus aureus and Trichophyton rubrum. The in vitro cytotoxicity studies employing L929 cells and A431 cells demonstrated good biocompatibility and enhanced anticancer activity of the curcumin-loaded green nanocomposite hydrogel compared to pure curcumin.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Curcumina/química , Curcumina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Celulose/química , Quitosana/química , Cucumis melo/química , Portadores de Fármacos/química , Hidrogéis/química , Nanocompostos/química , Nanopartículas/química , Sementes/química , Staphylococcus aureus/efeitos dos fármacos , Trichophyton/efeitos dos fármacos , Trichophyton/crescimento & desenvolvimento , Óxido de Zinco/química
3.
J Agric Food Chem ; 67(39): 10937-10946, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31508960

RESUMO

This paper attempted to construct a high internal phase emulsion (HIPE) through altering interfacial behaviors using the electrostatic interaction between positive chitosan and negative octenyl succinic anhydride (OSA) starch. The partial polysaccharide complex of OSA starch/chitosan was used to stabilize HIPE, which was able to adsorb at the oil droplet interface and prevent the coalescence of oil droplets. The wettability of OSA starch was enhanced with the addition of positively charged chitosan, leading to the formation of partial complexes. The impact of pH and concentration of chitosan on the droplet size, surface charge, and interface behavior were investigated, and the formation of the polysaccharide complex was further confirmed by atomic force microscopy. The presence of the OSA starch/chitosan complex facilitated the formation of stable HIPE with a gel-like structure and satisfactory centrifugal and oxidative stability. These results are useful to provide information for fabricating polysaccharide-based HIPE delivery systems, which may help expand their application in the food industry.


Assuntos
Quitosana/química , Amido/análogos & derivados , Emulsões/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Amido/química , Anidridos Succínicos/química
4.
Braz Oral Res ; 33: e075, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31432926

RESUMO

Resinous infiltrants are indicated in the treatment of incipient carious lesions, and further development of these materials may contribute to greater control of these lesions. The aim of this study was to analyze the physical and antibacterial properties of experimental infiltrants containing iodonium salt and chitosan. Nine experimental infiltrants were formulated by varying the concentration of the diphenyliodonium salt (DPI) at 0, 0.5 and 1 mol%; and chitosan at 0, 0.12 and 0.25 g%. The infiltrants contained the monomeric base of triethylene glycol dimethacrylate and bisphenol-A dimethacrylate ethoxylate in a 75 and 25% proportion by weight, respectively; 0.5 mol% camphorquinone and 1 mol% ethyl 4-dimethylaminobenzoate. The degree of conversion was evaluated using Fourier transformer infrared spectroscopy, and the flexural strength and elastic modulus using the three-point bending test. Sorption and solubility in water, and antibacterial analysis (minimum inhibitory concentration and minimum bactericidal concentration) were also analyzed. Data was analyzed statistically by two-way ANOVA and Tukey's test (p<0.05), with the exception of the antibacterial test, which was evaluated by visual inspection. In general, the infiltrant group containing 0.5% DPI and 0.12% chitosan showed high values of degree of conversion, higher values of elastic modulus and flexural strength, and lower sorption values in relation to the other groups. Antibacterial activity was observed in all the groups with DPI, regardless of the concentration of chitosan. The addition of DPI and chitosan to experimental infiltrants represents a valid option for producing infiltrants with desirable physical and antibacterial characteristics.


Assuntos
Antibacterianos/química , Quitosana/química , Resinas Compostas/química , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Sais/química , Análise de Variância , Antibacterianos/farmacologia , Quitosana/farmacologia , Resinas Compostas/farmacologia , Módulo de Elasticidade , Resistência à Flexão , Lactobacillus acidophilus/efeitos dos fármacos , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Metacrilatos/farmacologia , Testes de Sensibilidade Microbiana , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/farmacologia , Valores de Referência , Reprodutibilidade dos Testes , Sais/farmacologia , Solubilidade , Estatísticas não Paramétricas , Streptococcus mutans/efeitos dos fármacos
5.
Int J Nanomedicine ; 14: 4911-4929, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456637

RESUMO

Background: Apocynin (APO) is a bioactive phytochemical with prominent anti-inflammatory and anti-oxidant activities. Designing a nano-delivery system targeted to potentiate the gastric antiulcerogenic activity of APO has not been investigated yet. Chitosan oligosaccharide (COS) is a low molecular weight chitosan and its oral nanoparticulate system for potentiating the antiulcerogenic activity of the loaded APO has been described here. Methods: COS-nanoparticles (NPs) loaded with APO (using tripolyphosphate [TPP] as a cross-linker) were prepared by ionic gelation method and fully characterized. The chosen formula was extensively evaluated regarding in vitro release profile, kinetic analysis, and stability at refrigerated and room temperatures. Ultimately, the in vivo antiulcerogenic activity against ketoprofen (KP)-induced gastric ulceration in rats was assessed by macroscopic parameters including Paul's index and antiulcerogenic activity, histopathological examination, immunohistochemical (IHC) evaluation of cyclooxygenase-2 (COX-2) expression level in ulcerated gastric tissue, and biochemical measurement of oxidative stress markers and nitric oxide (NO) levels. Results: The selected NPs formula with COS (0.5 % w/v) and TPP (0.1% w/v) was the most appropriate one with drug entrapment efficiency percentage of 35.06%, particle size of 436.20 nm, zeta potential of +38.20 mV, and mucoadhesive strength of 51.22%. It exhibited a biphasic in vitro release pattern as well as high stability at refrigerated temperature for a 6-month storage period. APO-loaded COS-NPs provoked marvelous antiulcerogenic activity against KP-induced gastric ulceration in rats compared with free APO treated group, which was emphasized by histopathological, IHC, and biochemical studies. Conclusion: In conclusion, APO-loaded COS-NPs could be considered as a promising oral phytopharmaceutical nanoparticulate system for management of gastric ulceration.


Assuntos
Acetofenonas/administração & dosagem , Acetofenonas/farmacologia , Quitosana/química , Mucosa Gástrica/efeitos dos fármacos , Nanopartículas/química , Oligossacarídeos/química , Compostos Fitoquímicos/administração & dosagem , Compostos Fitoquímicos/farmacologia , Acetofenonas/uso terapêutico , Administração através da Mucosa , Animais , Biomarcadores/metabolismo , Varredura Diferencial de Calorimetria , Ciclo-Oxigenase 2/metabolismo , Liberação Controlada de Fármacos , Cinética , Masculino , Nanopartículas/ultraestrutura , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Estômago/efeitos dos fármacos , Estômago/patologia , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia , Suínos , Difração de Raios X
6.
7.
Analyst ; 144(17): 5108-5116, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31373337

RESUMO

We report here the influence of antibody immobilization strategy for protein immunosensors on screen printed carbon electrode arrays in terms of antibody binding activity, analytical sensitivity, limit of detection, and stability. Horseradish peroxidase (HRP) was the model analyte with anti-HRP immobilized on the sensors, and HRP activity was used for detection. Covalently immobilized anti-HRP antibodies on electrodes coated with chitosan, electrochemically reduced graphene oxide (rGO), and dense gold nanoparticle (AuNP) films had only 20-30% of the total immobilized antibodies active for binding. Active antibodies increased to 60% with passively adsorbed antibodies on bare electrodes, to 85% with oriented antibodies using protein A covalently immobilized on AuNP-coated carbon electrode, and to 98% when attached to protein A passively adsorbed onto bare electrodes. Passively adsorbed antibodies on bare electrodes lost activity in 1-2 days, but antibodies immobilized using other strategies remained relatively stable after 5 days. Covalent immobilization gave limits of detection (LOD) of 40 fg mL-1, while passively adsorbed antibodies or protein A on carbon electrodes had LODs 4-8 fg mL-1, but were unstable. Sensitivity was highest for antibodies covalently attached to AuNP electrodes (2.40 nA per log pg per mL) that also had highest antibody coverage, and decreased slightly when protein A on AuNP was used to orient antibodies. Passively adsorbed antibodies and oriented antibodies on protein A gave slightly lower sensitivities. Immobilization strategy or antibody orientation did not have a significant effect on LOD, but dynamic range increased as the number of active antibodies on sensor surfaces increased.


Assuntos
Anticorpos Imobilizados/química , Carbono/química , Técnicas Biossensoriais/métodos , Quitosana/química , Técnicas Eletroquímicas/métodos , Eletrodos , Grafite/química , Peroxidase do Rábano Silvestre/química , Imunoensaio/métodos , Limite de Detecção , Oxirredução , Propriedades de Superfície
8.
Int J Nanomedicine ; 14: 5287-5301, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31406460

RESUMO

Purpose: Nanoparticle (NP)-mediated targeted delivery of therapeutic genes or siRNAs to tumors has potential advantages. In this study, hyaluronic acid (HA)-modified chitosan nanoparticles (CS NPs-HA) loaded with cyanine 3 (Cy3)-labeled siRNA (sCS NPs-HA) were prepared and characterized. Methods: Human non-small cell lung cancer (NSCLC) A549 cells expressing receptor CD44 and tumor-bearing mice were used to evaluate the cytotoxic and antitumor effects of sCS NPs-HA in vitro and in vivo. Results: The results showed that noncytotoxic CS NPs-HA of small size (100-200 nm) effectively delivered the Cy3-labeled siRNA to A549 cells via receptor CD44 and inhibited cell proliferation by downregulating the target gene BCL2. In vivo experiment results revealed that sCS NPs-HA directly delivered greater amounts of Cy3-labeled siRNA to the tumor sites, resulting in the inhibition of tumor growth by downregulating BCL2, as compared to unmodified NPs loaded with siRNA (sCS NPs) and to naked Cy3-labeled siRNA. Conclusion: The HA-modified NPs based on chitosan could serve as a promising carrier for siRNA delivery and targeted therapy for NSCLC expressing CD44.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Quitosana/química , Ácido Hialurônico/química , Neoplasias Pulmonares/terapia , Nanopartículas/química , RNA Interferente Pequeno/administração & dosagem , Células A549 , Animais , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Fluorescência , Inativação Gênica , Humanos , Receptores de Hialuronatos/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , Nanopartículas/administração & dosagem
9.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(4): 275-278, 2019 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-31460720

RESUMO

Using three-dimensional printing to produce antibacterial wound dressing is a new topic that will change the production style of wound dressing industry. Combining with post-3D-printed process, a desktop fused deposition molding equipment can be used to produce wound dressing containing polyvinyl alcohol, alginate and chitosan. The wound dressing produced by FDM has good aspects of absorbency, moisture vapour transmission rate and mechanical property. After loaded with antibacterial agent iodine and silver nano particle, the antibacterial activity rate increases to 99% and it is suitable to use as antibacterial wound dressing. This method affects the production of wound dressing to a more cost-effective way, and provides a possible individualized treatment for patient in the future.


Assuntos
Antibacterianos , Bandagens , Impressão Tridimensional , Cicatrização , Alginatos/química , Antibacterianos/administração & dosagem , Bactérias/efeitos dos fármacos , Bandagens/economia , Bandagens/normas , Quitosana/química , Humanos , Iodo/administração & dosagem , Iodo/farmacologia , Nanopartículas/administração & dosagem , Álcool de Polivinil/química , Prata/administração & dosagem , Prata/farmacologia
10.
DNA Cell Biol ; 38(10): 1048-1055, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31433200

RESUMO

DNA condensed agents can improve the transfection efficiency of the cationic liposome delivery system. However, various condensed agents have distinct transfection efficiency and cellular cytotoxicity. The object of this study was to screen the optimal agents with the high transfection efficiency and low cytotoxicity from four polymer compressive materials, polyethylenimine (PEI), chitosan, poly-l-lysine (PLL), and spermidine. DNA was precompressed with these four agents and then combined to cationic liposomes. Subsequently, the entrapment and transfection efficiency of the obtained complexes were investigated. Finally, the particle sizes, cytotoxicity, and endocytosis fashion of these copolymers (Lipo-PEI, Lipo-chitosan, Lipo-PLL, and Lipo-spermidine) were examined. It was found that these four copolymers had significantly lower cytotoxicity and higher transfection efficiency (45.5%, 42.4%, 36.8%, and 47.4%, respectively) than those in the control groups. The transfection efficiency of Lipo-PEI and Lipo-spermidine copolymers were better than the other two copolymers. In 293T cells, nystatin significantly inhibited the transfection efficiency of Lipo-PEI-DNA and Lipo-spermidine-DNA (51.88% and 46.05%, respectively), which suggest that the endocytosis pathway of Lipo-spermidine and Lipo-PEI copolymers was probably caveolin dependent. Our study indicated that these dual-degradable copolymers especially liposome-spermidine copolymer could be used as the potential biocompatible gene delivery carriers.


Assuntos
Quitosana/química , Lipossomos/química , Polietilenoimina/química , Polilisina/química , Espermidina/química , Transfecção/métodos , Cátions , Caveolina 1/genética , Caveolina 1/metabolismo , Quitosana/metabolismo , Colesterol/química , Colesterol/metabolismo , Endocitose/efeitos dos fármacos , Endocitose/genética , Ácidos Graxos Monoinsaturados/química , Ácidos Graxos Monoinsaturados/metabolismo , Células HEK293 , Humanos , Lipossomos/metabolismo , Nistatina/farmacologia , Tamanho da Partícula , Plasmídeos/química , Plasmídeos/metabolismo , Polietilenoimina/metabolismo , Polilisina/metabolismo , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo , Espermidina/metabolismo
11.
Int J Nanomedicine ; 14: 5339-5353, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409991

RESUMO

Background: Like most protein macromolecular drugs, the half-life of rhIFNɑ-2b is short, with a low drug utilization rate, and the preparation and release conditions significantly affect its stability. Methods: A nanoporous ion-responsive targeted drug delivery system (PIRTDDS) was designed to improve drug availability of rhIFNα-2b and target it to the lung passively with sustained release. Chitosan rhIFNα-2b carboxymethyl nanoporous microspheres (CS-rhIFNα-2b-CCPM) were prepared by the column method. Here, an electrostatic self-assembly technique was undertaken to improve and sustain rhIFNα-2b release rate. Results: The size distribution of the microspheres was 5~15 µm, and the microspheres contained nanopores 300~400 nm in diameter. The in vitro release results showed that rhIFNα-2b and CCPM were mainly bound by ionic bonds. After self-assembling, the release mechanism was transformed into being membrane diffusion. The accumulative release amount for 24 hrs was 83.89%. Results from circular dichrogram and SDS-PAGE electrophoresis showed that there was no significant change in the secondary structure and purity of rhIFNα-2b. Results from inhibition rate experiments for A549 cell proliferation showed that the antitumor activity of CS-rhIFNα-2b-CCPM for 24 hrs retained 91.98% of the stock solution, which proved that the drug-loaded nanoporous microspheres maintained good drug activity. In vivo pharmacokinetic experimental results showed that the drugs in CS-rhIFNα-2b-CCPM can still be detected in vivo after 24 hrs, equivalent to the stock solution at 6 hrs, which indicated that CS-rhIFNα-2b-CCPM had a certain sustained-release effect in vivo. The results of in vivo tissue distribution showed that CS-rhIFNα-2b-CCPM was mainly concentrated in the lungs of mice (1.85 times the stock solution). The pharmacodynamics results showed that CS-rhIFNα-2b-CCPM had an obvious antitumor effect, and the tumor inhibition efficiency was 29.2%. Conclusion: The results suggested a novel sustained-release formulation with higher drug availability and better lung targeting from CS-rhIFNα-2b-CCPM compared to the reference (the stock solution of rhIFNα-2b), and, thus, should be further studied.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Interferon alfa-2/administração & dosagem , Nanoporos , Células A549 , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Quitosana/análogos & derivados , Quitosana/química , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Humanos , Interferon alfa-2/sangue , Interferon alfa-2/farmacocinética , Interferon alfa-2/farmacologia , Troca Iônica , Cinética , Masculino , Camundongos Endogâmicos ICR , Microesferas , Tamanho da Partícula , Permeabilidade , Eletricidade Estática , Distribuição Tecidual
12.
Int J Nanomedicine ; 14: 5503-5526, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410001

RESUMO

Background and purpose: Glioma is one of the most aggressive primary brain tumors and is incurable. Surgical resection, radiation, and chemotherapies have been the standard treatments for brain tumors, however, they damage healthy tissue. Therefore, there is a need for safe anticancer drug delivery systems. This is particularly true for natural prodrugs such as thymoquinone (TQ), which has a high therapeutic potential for cancers but has poor water solubility and insufficient targeting capacity. We have tailored novel core-shell nanoformulations for TQ delivery against glioma cells using mesoporous silica nanoparticles (MSNs) as a carrier. Methods: The core-shell nanoformulations were prepared with a core of MSNs loaded with TQ (MSNTQ), and the shell consisted of whey protein and gum Arabic (MSNTQ-WA), or chitosan and stearic acid (MSNTQ-CS). Nanoformulations were characterized, studied for release kinetics and evaluated for anticancer activity on brain cancer cells (SW1088 and A172) and cortical neuronal cells-2 (HCN2) as normal cells. Furthermore, they were evaluated for caspase-3, cytochrome c, cell cycle arrest, and apoptosis to understand the possible anticancer mechanism. Results: TQ release was pH-dependent and different for core and core-shell nanoformulations. A high TQ release from MSNTQ was detected at neutral pH 7.4, while a high TQ release from MSNTQ-WA and MSNTQ-CS was obtained at acidic pH 5.5 and 6.8, respectively; thus, TQ release in acidic tumor environment was enhanced. The release kinetics fitted with the Korsmeyer-Peppas kinetic model corresponding to diffusion-controlled release. Comparative in vitro tests with cancer and normal cells indicated a high anticancer efficiency for MSNTQ-WA compared to free TQ, and low cytotoxicity in the case of normal cells. The core-shell nanoformulations significantly improved caspase-3 activation, cytochrome c triggers, cell cycle arrest at G2/M, and apoptosis induction compared to TQ. Conclusion: Use of MSNs loaded with TQ permit improved cancer targeting and opens the door to translating TQ into clinical application. Particularly good results were obtained for MSNTQ-WA.


Assuntos
Antineoplásicos/uso terapêutico , Benzoquinonas/uso terapêutico , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Glioma/tratamento farmacológico , Nanopartículas/química , Dióxido de Silício/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Materiais Biocompatíveis/química , Encéfalo/patologia , Varredura Diferencial de Calorimetria , Caspase 3/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quitosana/química , Citocromos c/metabolismo , Difusão , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Cinética , Nanopartículas/ultraestrutura , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
13.
Food Chem ; 301: 125247, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377626

RESUMO

In this work, we developed a simple method for the preparation of N-(3-azido-2-hydroxypropyl)chitosan. We compared the antibacterial activity of N-(3-azido-2-hydroxypropyl)chitosans and previously synthesized N-(2-azidoethyl)chitosans. N-(3-azido-2-hydroxypropyl)chitosans possess higher antibacterial effect which is comparable with that of ampicillin and gentamicin. The effect is due to azido pharmacophore -CH2-CH(OH)-CH2-N3 (for N-(3-azido-2-hydroxypropyl)chitosan) or -CH2-CH2-N3 (for N-(2-azidoethyl)chitosan) introduced in chitosan chain, since the corresponding organic azides NH2-CH2-CH2-N3 and NH2-CH2-CH2-N3 are characterized by high antibacterial activity. However, high antibacterial organic azides NH2-CH2-CH2-N3 and NH2-CH2-CH2-N3 are characterized by high toxicity. Their conjugation to the chitosan chain saves their antibacterial effect, but strongly diminishes their toxicity, and the toxicity of the resulting derivatives is comparable with that of the starting chitosan. These findings are of interest to food science, since novel effective food coatings can be developed on basis of prepared derivatives.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Azidas/química , Quitosana/química , Quitosana/farmacologia , Embalagem de Alimentos , Antibacterianos/toxicidade , Quitosana/toxicidade
14.
Food Chem ; 299: 125109, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31295635

RESUMO

The aim of this research is to develop, characterize and utilize a multi-layer antibacterial film using chitosan (CS) and sodium alginate (SA) as biopolymers and cinnamon essential oil (CEO) as main antibacterial ingredients. The dense cross-section of SA layer in the scanning electron microscopy (SEM) analysis verified that layer-by-layer method improved physical and mechanical properties of CS-CEO single layer film. The thermogravimetric (TGA) and fourier transform infrared (FT-IR) analysis indicated that the layer-by-layer method changed the intermolecular interaction and the thermal stability. Importantly, the multi-layer film exhibited more sustained release and higher retention rate of CEO compared CS-CEO single layer film. The multi-layer coating showed a more significant and lasting inhibition of penicillium expansion which further demonstrated that the layer-by-layer method improved the release and retention of CEO in the multiphased system. To summarize, the multilayer film system is a promising controllable release system for loading essential oils.


Assuntos
Antifúngicos/farmacologia , Cinnamomum zeylanicum/química , Malus/microbiologia , Óleos Voláteis/farmacologia , Penicillium/efeitos dos fármacos , Alginatos/química , Antifúngicos/química , Quitosana/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Frutas/efeitos dos fármacos , Frutas/microbiologia , Malus/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Óleos Voláteis/farmacocinética , Penicillium/patogenicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria
15.
Food Chem ; 298: 125041, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261000

RESUMO

Edible packaging films play an important role in extending the shelf life of food products. In this work, the properties of cellulose nanofiber (CNF) reinforced hemicelluloses/chitosan-based edible films with xylooligosaccharides (XOS) have been evaluated. Results showed that the tensile strength (TS) of the film can be increased by 2.5 times with adding 5 wt% CNF. Incorporating 1.79-7.18% XOS into hemicelluloses-chitosan matrix only caused slightly higher water vapor permeability, and the composite films exhibited good hydrophobicity, thermal stability, and high transparency. The hemicelluloses/chitosan films with 1.79-5.38% XOS had higher TS (42.7-50.7 MPa) and lower oxygen permeability (OP, 4.95-5.06 cm3 µm/m2·day·kPa) than those containing 7.18% XOS. Additionally, ∼92.6% XOS in films can be released in simulated gastric fluid within 60 min. Overall, XOS (1.79-5.38%) with prebiotic properties can be added to films successfully to improve the functionality and the films were fit for food-packaging where high TS and low OP are required.


Assuntos
Celulose/química , Quitosana/química , Glucuronatos/química , Nanofibras/química , Oligossacarídeos/química , Embalagem de Alimentos/métodos , Suco Gástrico , Humanos , Microscopia Eletrônica de Varredura , Permeabilidade , Polissacarídeos/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Resistência à Tração , Difração de Raios X
16.
Food Chem ; 298: 125064, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260954

RESUMO

Edible films based on gelatin and chitosan have high gas and aroma barrier properties. This study focused on their capability to sorbed/retain aroma compounds (1-hexanal, 2-hexen-1-ol, 1-hexanol, 3-hexanone and phenol) at three relative humidity level (≤2%, 53% or 84% RH). Whatever the relative humidity condition, the order of sorption is keton (3-hexanone) < aldehyde (1-hexanal) < aliphatic alcohols (2-hexen-1-ol and 1-hexanol) < phenol. This order could be related to the intrinsic chemical properties of aroma compounds. The increase in moisture enhanced the sorption at the highest RH for all the aroma compounds. However, a competition between water and aliphatic alcohols is observed at 53%RH. All compounds have an ideal sorption behaviour (logarithmic increase) except 1-hexanal. The sorption of 1-hexanal, 1-hexanol, 2-hexen-1-ol and 3-hexanone induced an antiplasticization of the network by increasing the film Tg by more than 5 °C. On the contrary, phenol was an efficient plasticizer at least as high as moisture.


Assuntos
Quitosana/química , Gelatina/química , Compostos Orgânicos Voláteis/química , Adsorção , Álcoois/química , Varredura Diferencial de Calorimetria , Cromatografia Gasosa , Umidade , Cetonas/química , Cinética , Fenol/química , Temperatura Ambiente
17.
J Agric Food Chem ; 67(31): 8700-8705, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31294561

RESUMO

This study reported a new headspace gas chromatography (HS-GC) for simultaneously determining the degree of deacetylation (DD) and the degree of substitution (DS) in carboxymethyl chitosan (CMCS), which were based on HS-GC measuring the amounts of CO2 released from both the bicarbonate decomposition suppressed by -NH2 and the reaction between the bicarbonate and the acidified carboxymethyl and amino groups in CMCS. The results showed that the present method has a good measurement precision (RSD < 2.55%) and accuracy (relative differences <5.90%). Compared with the current titration-based method, the present HS-GC techniques provide a more reliable testing in the quantification of amino and carboxymethyl contents in CMCS. Moreover, since the HS-GC can perform an automated sample reaction equilibration and measurement, it could be much more efficient than the existing methods in the batch sample analysis.


Assuntos
Quitosana/análogos & derivados , Cromatografia Gasosa/métodos , Acetilação , Quitosana/química
18.
J Agric Food Chem ; 67(31): 8609-8616, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31314514

RESUMO

Quercetin (QUE)-loaded nanoparticles (QCG-NPs) were fabricated by ionic gelation between chitosan (CS) and gum arabic (GA) at pH 3.5. At constant CS (0.5 mg/mL) and QUE (60 µM) concentrations, QCG-NPs (260-490 nm) were prepared uniformly with 0.8-2.2 mg/mL GA and exhibited high QUE encapsulation efficiency (94.8-98.0%) and sustained QUE release (4.42-8.89% after 8 h). Because of the electrostatic interaction between QCG-NPs and the mucin layer, in vitro mucin and cell adhesion of QUE were significantly (p < 0.05) enhanced in QCG-NPs (0.44-0.48 mg/mL and 31.7-78.5%), respectively, and the adhesiveness was significantly (p < 0.05) increased with an increase of GA. Because particle size and adhesion properties affect the surface area and retention time of QCG-NPs at the absorption site, cell permeation of QUE through simple diffusion by QCG-NPs exhibited the same tendency as the adhesion results. These data were verified in cellular antioxidant and in vivo ferric reducing abilities of plasma assays that evaluated the antioxidant activities of QUE absorbed into an intestinal cell model and rat blood, respectively. The results provide a better understanding of QCG-NP absorption and indicate that QCG-NPs with mucoadhesion properties can be an effective delivery system for improving QUE absorption.


Assuntos
Antioxidantes/química , Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Mucosa Intestinal/metabolismo , Nanopartículas/química , Quercetina/química , Quercetina/metabolismo , Animais , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Células CACO-2 , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Humanos , Tamanho da Partícula , Quercetina/administração & dosagem , Ratos , Ratos Sprague-Dawley
19.
J Environ Sci (China) ; 84: 21-28, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284913

RESUMO

It is urgent to explore an effective removal method for perfluorooctanoic acid (PFOA) due to its recalcitrant nature. In this study, a novel chitosan-based hydrogel (CEGH) was prepared with a simple method using chitosan and ethylene glycol through a repeated freezing-thawing procedure. The adsorption of PFOA anions to CEGH agreed well to the Freundlich-Langmuir model with a maximum adsorption capacity as high as 1275.9 mg/g, which is higher than reported values of most adsorbents for PFOA. The adsorption was influenced by experimental conditions. Experimental results showed that the main removal mechanism was the ionic hydrogen bond interaction between carbonyl groups (COO-) of PFOA and protonated amine (NH+) of the CEGH adsorbent. Therefore, CEGH is a very attractive adsorbent that can be used to remove PFOA from water in the future.


Assuntos
Caprilatos/isolamento & purificação , Quitosana/química , Etilenoglicol/química , Fluorcarbonetos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Hidrogéis , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica
20.
J Photochem Photobiol B ; 197: 111539, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31301638

RESUMO

Treatment of burn injury is clinically challenging one, therefore several steps and noteworthy approaches have been taken to improve wound mechanisms. Citrus pectin plays a stabilizing agent to synthesis of ZnO nanoparticles (ZnO NPs). The present study is focused on ZnO loaded collagen/chitosan nanofibrous were synthesized by electrospinning method using ZnO NPs. The chemical structure, phase purity and morphological observation were investigated under spectroscopic and mircoscopic techniques and demonstrated their suitable properties as a wound healing material. In addition, that prepared nanoparticles loaded biopolymeric fibrous nanomaterial showed suitable antibacterial activity against S. aureus and E. coli bacterial pathogens and also in vitro studies was confirmed the enhanced proliferation, cell viability and biocompatibility. In vitro evaluations have been exhibited acceptable cell proliferation is observed throughout the ZnO loaded Coll/CS nanofibrous within 3 days, which was comparable to the control material. In vivo wound healing ability was monitored on the rat wound experimental model. From the in vivo observations, revealed that the loaded of ZnO NPs with Coll/CS nanofibrous can effectively quicken wound healing mechanism, expressed in the initial stage healing process. These results suggest that ZnO loaded collagen/chitosan nanofibrous is a potential candidate for wound healing applications with enhanced biological properties.


Assuntos
Queimaduras/patologia , Quitosana/química , Colágeno/química , Nanopartículas Metálicas/química , Nanofibras/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Queimaduras/veterinária , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Nanofibras/uso terapêutico , Nanofibras/toxicidade , Ratos , Pele/efeitos dos fármacos , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Óxido de Zinco/química
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