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1.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202115

RESUMO

The literature indicates the existence of a relationship between rhamnolipids and bacterial biofilm, as well as the ability of selected bacteria to produce rhamnolipids and alginate. However, the influence of biosurfactant molecules on the mechanical properties of biofilms are still not fully understood. The aim of this research is to determine the effect of rhamnolipids concentration, CaCl2 concentration, and ionic cross-linking time on the mechanical properties of alginate hydrogels using a Box-Behnken design. The mechanical properties of cross-linked alginate hydrogels were characterized using a universal testing machine. It was assumed that the addition of rhamnolipids mainly affects the compression load, and the value of this parameter is lower for hydrogels produced with biosurfactant concentration below CMC than for hydrogels obtained in pure water. In contrast, the addition of rhamnolipids in an amount exceeding CMC causes an increase in compression load. In bacterial biofilms, the presence of rhamnolipid molecules does not exceed the CMC value, which may confirm the influence of this biosurfactant on the formation of the biofilm structure. Moreover, rhamnolipids interact with the hydrophobic part of the alginate copolymer chains, and then the hydrophilic groups of adsorbed biosurfactant molecules create additional calcium ion trapping sites.


Assuntos
Alginatos/química , Bactérias/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Glicolipídeos/química , Hidrogéis/química , Líquidos Iônicos/química , Algoritmos , Modelos Teóricos
2.
Int J Mol Sci ; 22(11)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071110

RESUMO

Rectal drug delivery is an effective alternative to oral and parenteral treatments. This route allows for both local and systemic drug therapy. Traditional rectal dosage formulations have historically been used for localised treatments, including laxatives, hemorrhoid therapy and antipyretics. However, this form of drug dosage often feels alien and uncomfortable to a patient, encouraging refusal. The limitations of conventional solid suppositories can be overcome by creating a thermosensitive liquid suppository. Unfortunately, there are currently only a few studies describing their use in therapy. However, recent trends indicate an increase in the development of this modern therapeutic system. This review introduces a novel rectal drug delivery system with the goal of summarising recent developments in thermosensitive liquid suppositories for analgesic, anticancer, antiemetic, antihypertensive, psychiatric, antiallergic, anaesthetic, antimalarial drugs and insulin. The report also presents the impact of various types of components and their concentration on the properties of this rectal dosage form. Further research into such formulations is certainly needed in order to meet the high demand for modern, efficient rectal gelling systems. Continued research and development in this field would undoubtedly further reveal the hidden potential of rectal drug delivery systems.


Assuntos
Administração Retal , Géis/administração & dosagem , Preparações Farmacêuticas/administração & dosagem , Supositórios/administração & dosagem , Resinas Acrílicas/química , Alginatos/química , Temperatura Corporal , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Previsões , Géis/química , Temperatura Alta , Humanos , Absorção Intestinal , Metilcelulose/química , Poloxâmero/química , Povidona/química , Supositórios/química
3.
Int J Mol Sci ; 22(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071329

RESUMO

Avascular transplantation of frozen-thawed testicular tissue fragments represents a potential future technique for fertility restoration in boys with cancer. A significant loss of spermatogonia was observed in xeno-transplants of human tissue most likely due to the hypoxic period before revascularization. To reduce the effect of hypoxia-reoxygenation injuries, several options have already been explored, like encapsulation in alginate hydrogel and supplementation with nanoparticles delivering a necrosis inhibitor (NECINH) or VEGF. While these approaches improved short-term (5 days) vascular surfaces in grafts, neovessels were not maintained up to 21 days; i.e., the time needed for achieving vessel stabilization. To better support tissue grafts, nanoparticles loaded with VEGF, PDGF and NECINH were developed. Testicular tissue fragments from 4-5-week-old mice were encapsulated in calcium-alginate hydrogels, either non-supplemented (control) or supplemented with drug-loaded nanoparticles (VEGF-nanoparticles; VEGF-nanoparticles + PDGF-nanoparticles; NECINH-nanoparticles; VEGF-nanoparticles + NECINH-nanoparticles; and VEGF-nanoparticles + PDGF-nanoparticles + NECINH-nanoparticles) before auto-transplantation. Grafts were recovered after 5 or 21 days for analyses of tissue integrity (hematoxylin-eosin staining), spermatogonial survival (immuno-histo-chemistry for promyelocytic leukemia zinc finger) and vascularization (immuno-histo-chemistry for α-smooth muscle actin and CD-31). Our results showed that a combination of VEGF and PDGF nanoparticles increased vascular maturity and induced a faster maturation of vascular structures in grafts.


Assuntos
Hidrogéis/química , Nanopartículas/administração & dosagem , Neovascularização Fisiológica/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/administração & dosagem , Testículo/transplante , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Alginatos/química , Animais , Liberação Controlada de Fármacos , Preservação da Fertilidade/métodos , Humanos , Masculino , Camundongos Endogâmicos , Nanopartículas/química , Fator de Crescimento Derivado de Plaquetas/química , Fator de Crescimento Derivado de Plaquetas/farmacocinética , Espermatogônias/efeitos dos fármacos , Testículo/irrigação sanguínea , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/farmacocinética
4.
Int J Mol Sci ; 22(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072085

RESUMO

In the fast-developing field of tissue engineering there is a constant demand for new materials as scaffolds for cell seeding, which can better mimic a natural extracellular matrix as well as control cell behavior. Among other materials, polysaccharides are widely used for this purpose. One of the main candidates for scaffold fabrication is alginate. However, it lacks sites for cell adhesion. That is why one of the steps toward the development of suitable scaffolds for cells is the introduction of the biofunctionality to the alginate structure. In this work we focused on bone-sialoprotein derived peptide (TYRAY) conjugation to the molecule of alginate. Here the comparison study on four different approaches of peptide conjugation was performed including traditional and novel modification methods, based on 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxy succinimide (EDC/NHS), 4-(4,6-dimethoxy-1,3,5-triazine-2-yl)-4-methylmorpholinium chloride (DMTMM), thiol-Michael addition and Cu-catalyzed azide-alkyne cycloaddition reactions. It was shown that the combination of the alginate amidation with the use of and subsequent Cu-catalyzed azide-alkyne cycloaddition led to efficient peptide conjugation, which was proven with both NMR and XPS methods. Moreover, the cell culture experiment proved the positive effect of peptide presence on the adhesion of human embryonic stem cells.


Assuntos
Alginatos/química , Biomimética , Peptídeos/química , Engenharia Tecidual , Tecidos Suporte , Aminas/química , Biomimética/métodos , Adesão Celular , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Química Click , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Peptídeos/farmacologia , Engenharia Tecidual/métodos
5.
Int J Mol Sci ; 22(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072090

RESUMO

Hydrogels obtained from combining different polymers are an interesting strategy for developing controlled release system platforms and tissue engineering scaffolds. In this study, the applicability of sodium alginate-g-(QCL-co-HEMA) hydrogels for these biomedical applications was evaluated. Hydrogels were synthesized by free-radical polymerization using a different concentration of the components. The hydrogels were characterized by Fourier transform-infrared spectroscopy, scanning electron microscopy, and a swelling degree. Betamethasone release as well as the in vitro cytocompatibility with chondrocytes and fibroblast cells were also evaluated. Scanning electron microscopy confirmed the porous surface morphology of the hydrogels in all cases. The swelling percent was determined at a different pH and was observed to be pH-sensitive. The controlled release behavior of betamethasone from the matrices was investigated in PBS media (pH = 7.4) and the drug was released in a controlled manner for up to 8 h. Human chondrocytes and fibroblasts were cultured on the hydrogels. The MTS assay showed that almost all hydrogels are cytocompatibles and an increase of proliferation in both cell types after one week of incubation was observed by the Live/Dead® assay. These results demonstrate that these hydrogels are attractive materials for pharmaceutical and biomedical applications due to their characteristics, their release kinetics, and biocompatibility.


Assuntos
Alginatos/química , Betametasona/administração & dosagem , Portadores de Fármacos , Hidrogéis/química , Metacrilatos/química , Polímeros/química , Tecidos Suporte/química , Animais , Técnicas de Cultura de Células , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Condrócitos , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Hidrogéis/síntese química , Cinética , Camundongos , Estrutura Molecular , Análise Espectral
6.
Food Chem ; 362: 130151, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087707

RESUMO

Hydrogels based on alginate and methylcellulose were developed as a colorimetric indicator for monitoring minced pork spoilage. The hydrogel was fabricated by an external gelation method using Ca2+ as the crosslinking agent. The pH-sensitive dye bromothymol blue was incorporated into the hydrogel to act as an indicator. The hydrogel's swelling index increased with an increasing ratio of methylcellulose, suggesting that the water uptake capacity is tunable by the polymer composition. The hydrogel's compression strength is directly proportional to the alginate content. The hydrogel indicator demonstrated a color change from orange to yellow (day 6) upon detecting total volatile basic nitrogen (TVB-N) built up in the package during minced pork storage at 4 °C, and the results showed a positive correlation between the color change, TVB-N and pH change of minced pork. This result demonstrated the potential application of the hydrogel as a spoilage indicator in intelligent packaging.


Assuntos
Amônia/análise , Colorimetria/métodos , Análise de Alimentos/métodos , Hidrogéis/química , Carne de Porco/análise , Alginatos/química , Animais , Azul de Bromotimol/química , Cálcio/química , Cor , Colorimetria/instrumentação , Análise de Alimentos/instrumentação , Qualidade dos Alimentos , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Metilcelulose/química , Nitrogênio/análise , Suínos , Água/química
7.
J Ind Microbiol Biotechnol ; 48(5-6)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34137896

RESUMO

Fructooligosaccharides (FOSs)-fructose-based oligosaccharides-are typical prebiotics with health-promoting effects in humans and animals. The trisaccharide 1-kestotriose is the most attractive inulin-type FOS. We previously reported a recombinant sucrose:sucrose 1-fructosyltransferase (1-SST, EC 2.4.1.99) from Schedonorus arundinaceus (Sa) that efficiently converts sucrose into 1-kestotriose. In this study, Pichia pastoris PGFT6x-308 constitutively expressing nine copies of the Sa1-SST gene displayed fructosyltransferase activity in undisrupted biomass (49.8 U/ml) and culture supernatant (120.7 U/ml) in fed-batch fermentation (72 hr) with sugarcane molasses. Toluene permeabilization increased 2.3-fold the Sa1-SSTrec activity of whole cells entrapped in calcium-alginate beads. The reaction with refined or raw sugar (600 g/l) yielded 1-kestotriose and 1,1-kestotetraose in a ratio of 8:2 with their sum representing above 55% (wt/wt) of total carbohydrates. The FOSs yield decreased to 45% (wt/wt) when sugarcane syrup and molasses were used as cheaper sucrose sources. The beads retained 80% residual Sa1-SSTrec activity after a 30-day batchwise operation with refined cane sugar at 30°C and pH 5.5. The immobilized biocatalyst is attractive for the continuous production of short-chain FOSs, most particularly 1-kestotriose.


Assuntos
Hexosiltransferases/metabolismo , Oligossacarídeos/metabolismo , Pichia/metabolismo , Alginatos/química , Carboidratos/análise , Permeabilidade da Membrana Celular/efeitos dos fármacos , Células Imobilizadas , Fermentação , Hexosiltransferases/genética , Humanos , Microbiologia Industrial , Inulina/metabolismo , Melaço , Pichia/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomycetales , Sacarose , Tolueno/farmacologia , Trissacarídeos/biossíntese
8.
Molecules ; 26(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071673

RESUMO

Calcium phosphate cements have the advantage that they can be prepared as a paste that sets in a few minutes and can be easily adapted to the shape of the bone defect, which facilitates its clinical application. In this research, six formulations of brushite (dicalcium phosphate dihydrated) cement were obtained and the effect of the addition of sodium alginate was analyzed, such as its capacity as a tetracycline release system. The samples that contain sodium alginate set in 4 or 5 min and showed a high percentage of injectability (93%). The cements exhibit compression resistance values between 1.6 and 2.6 MPa. The drug was released in a range between 12.6 and 13.2% after 7 days. The antimicrobial activity of all the cements containing antibiotics was proven. All samples reached values of cell viability above 70 percent. We also observed that the addition of the sodium alginate and tetracycline improved the cell viability.


Assuntos
Alginatos/química , Cimentos Ósseos/química , Fosfatos de Cálcio/química , Tetraciclina/farmacologia , Células 3T3-L1 , Animais , Antibacterianos/química , Materiais Biocompatíveis/química , Regeneração Óssea , Proliferação de Células , Sobrevivência Celular , Força Compressiva , Concentração de Íons de Hidrogênio , Camundongos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Pressão , Estresse Mecânico , Tetraciclina/química , Fatores de Tempo , Engenharia Tecidual , Difração de Raios X
9.
Int J Biol Macromol ; 183: 2152-2161, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34097965

RESUMO

Alginate has been widely applied in various biological systems due to its great biocompatibility. Endowing it fluorescent imaging would make people to further understand its complex structure, process and mechanism. In this work, amphiphilic alginate conjugated with aggregation-induced emission (AIE) moiety fluorescent polymer was successfully fabricated through the Ugi one-pot condensation. The synthetic polymer particles were fully evaluated by various characterizations including 1H NMR, FTIR, fluorescent spectroscopies, and transmission electron microscopy (TEM). These amphiphilic alginate particles showed great multicolor fluorescence emission in both solid and solution states. The corresponding biological evaluation results confirmed that the fluorescent biopolymer showed excellent biocompatibility and desirable bioimaging property. Particularly, the leaf stomata were directly visualized using the amphiphilic AIE-active alginate biopolymer. Furthermore, the alginate-based polymer can also be employed as the drug carrier for hydrophobic curcumin. These results indicated that our synthetic AIE-active alginate particles might provide great potential for the further utilization of alginate in the understanding of various relative biological systems.


Assuntos
Alginatos/química , Curcumina/química , Portadores de Fármacos , Corantes Fluorescentes/química , Microscopia de Fluorescência , Nanopartículas , Imagem Óptica , Estômatos de Plantas , Células 3T3 , Alginatos/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Corantes Fluorescentes/toxicidade , Camundongos , Musa
10.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946988

RESUMO

The aim of the study was to investigate the changes within the physicochemical properties of gelatin, carrageenan, and sodium alginate hydrosols prepared on the basis of micro-clustered (MC) water. The rheological parameters, contact angle and antioxidant activity of hydrosols were investigated. Moreover, the pH, oxidation-reduction potential (ORP) and electrical conductivity (EC) were measured. The hydrosols with MC water were characterized by a lower pH, decreased viscosity, a lower contact angle, and only slightly lower antioxidant activity than control samples. The results showed that hydrosol's properties are significantly changed by MC water, which can lead to enhancement of its applicability but requires further investigation.


Assuntos
Alginatos/química , Carragenina/química , Aditivos Alimentares/química , Gelatina/química , Polímeros/química , Solventes/química , Água/química , Antioxidantes , Condutividade Elétrica , Conservação de Alimentos/métodos , Concentração de Íons de Hidrogênio , Oxirredução , Gases em Plasma , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Reologia , Solubilidade , Viscosidade
11.
Int J Biol Macromol ; 183: 1236-1247, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33965488

RESUMO

Microencapsulation is a potential biotechnological tool, which can overcome antimicrobial peptides (AMP) instabilities and reduce toxic side effects. Thus, this study evaluates the antibacterial activities of the Ctx(Ile21)-Ha AMP against multidrug-resistant (MDR) and non-resistant bacteria and develop and characterize peptide-loaded microparticles coated with the enteric polymers hydroxypropylmethylcellulose acetate succinate (HPMCAS) and hydroxypropylmethylcellulose phthalate (HPMCP). Ctx(Ile21)-Ha was obtained by solid phase peptide synthesis (SPPS) method, purified and characterized by HPLC and Mass Spectrometry. The peptide exhibited potent antibiotic activities against Salmonella enteritidis, Salmonella typhimurium, Pseudomonas aeruginosa (MDR), Acinetobacter baumannii (MDR), and Staphylococcus aureus (MDR). Ctx(Ile21)-Ha microencapsulation was performed by ionic gelation with high efficiency, maintaining the physical-chemical stability. Ctx(Ile21)-Ha coated-microparticles were characterized by DSC, TGA, FTIR-Raman, XRD and SEM. Hemolytic activity assay demonstrated that hemolysis was decreased up to 95% compared to single molecule. In addition, in vitro release control profile simulating different portions of gastrointestinal tract was performed and showed the microcapsules' ability to protect the peptide and release it in the intestine, aiming pathogen's location, mainly by Salmonella sp. Therefore, use of microencapsulated Ctx(Ile21)-Ha can be allowed as an antimicrobial controller in monogastric animal production as an oral feed additive (antimicrobial controller), being a valuable option for molecules with low therapeutic indexes or high hemolytic rates.


Assuntos
Alginatos/química , Metilcelulose/análogos & derivados , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Composição de Medicamentos , Aditivos Alimentares/química , Aditivos Alimentares/farmacologia , Hemólise , Metilcelulose/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Proteínas Citotóxicas Formadoras de Poros/química , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
12.
Int J Biol Macromol ; 183: 627-634, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33957198

RESUMO

Preserving the efficacy of plant probiotic bacteria in soil is a major challenge to the biological control of plant diseases. The microencapsulation technique is an important step in preserving the viability and activity of probiotics in adverse environmental conditions. The main objective of this study was to choose an appropriate coating for probiotic encapsulation. For this purpose, the survivability and controlled release of Pseudomonas fluorescens VUPF506 encapsulated with alginate (Alg) combined with whey protein concentrate (WPC), carboxymethyl cellulose (CMC), and peanut butter (PB) were evaluated. Moreover, the encapsulated cells were evaluated to control for Rhizoctonia solani in potato plants under in vivo conditions. The results showed that all tested wall material maintained more than 80% of the bacterial cells. The Alg-WPC microcapsules provided a better controlled release over two months. Interestingly, the greenhouse experiment also revealed that the treatment of potato plants with Alg-WPC microcapsules was the most effective treatment, suppressing 90% of the pathogen. The results showed that Alg-WPC is the most promising combination to improve the survivability of P. fluorescens VUPF506. Moreover, it can be used as a fertilizer due to its content of valuable amino acids.


Assuntos
Alginatos/química , Controle Biológico de Vetores , Doenças das Plantas/prevenção & controle , Raízes de Plantas/microbiologia , Probióticos , Pseudomonas fluorescens/crescimento & desenvolvimento , Rhizoctonia/crescimento & desenvolvimento , Solanum tuberosum/microbiologia , Cápsulas , Preparações de Ação Retardada , Doenças das Plantas/microbiologia , Fatores de Tempo
13.
Int J Biol Macromol ; 183: 962-971, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33965483

RESUMO

The present work aims to synthesize the rifaximin loaded chitosan-alginate core-shell nanoparticles (Rif@CS/Alg-NPs) for antibacterial applications. The core-shell nanoparticles (Rif@CS/Alg-NPs) were characterized by Fourier Transform Infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-rays diffraction (XRD) and zeta analyzer. The antibacterial activities of Rif@CS/Alg-NPs were investigated against three species of bacteria namely Escherichia coli (E. coli), Pseudomonas aeruginosa (PA) and Bacillus haynesii (BH). Rif@CS/Alg-NPs exhibited outstanding antibacterial activities against E. coli, P. aeroginosa and Bacillus haynesii (BH) with 24 mm, 30 mm and 34 mm zone of inhibitions, respectively. Cytotoxicity of Rif@CS/Alg-NPs was also evaluated against human lung adenocarcinoma cell line A549 and found to be nontoxic. The drug release behavior of Rif@CS/Alg-NPs was investigated at different pH levels and maximum drug release (80%) was achieved at pH (7.2). The drug release kinetic data followed the Higuchi (R2 = 0.9963) kinetic model, indicating the drug release from Rif@CS/Alg-NPs as a square root of time-dependent process and diffusion controlled. Current research provides a cost-effective and green approach toward the synthesis of Rif@CS/Alg-NPs for its antibacterial applications.


Assuntos
Alginatos/química , Antibacterianos/química , Quitosana/química , Nanopartículas/química , Rifaximina/química , Bacillus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Cinética , Pseudomonas aeruginosa/efeitos dos fármacos
14.
Int J Biol Macromol ; 183: 1013-1025, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33974922

RESUMO

We develop a robust micro-patterned double-layer film that can adhere firmly to the tissue and provide a sustained release of ascorbic acid (AA) for corneal regeneration. This double-layer film consists of a AA reservoir sodium alginate (SA) adhesive and an anisotropic layer made of micro-patterned silk nanofibrils (SNF) incorporated gelatin methacrylate (GelMA) (S/G). The S/G layer facilitates the adhesion and orientation of corneal stroma cells, depending on the pattern sizes (50 µm (P1) and 100 (P2) µm). Results reveal that more than 90% and 80% of the cells are located at angles close to the vertical axis (0-20°) in the sample with the smaller and larger pattern size, respectively. The mechanical robustness and 90% light transmission of this hybrid film originate from the micro-patterned S/G layer. However, the micro-pattern size does not show a significant role in the mechanical properties of hybrid films (tensile strength of S/G-SA, S/G-SA(P1), and S/G-SA(P2) is 3.4 ± 0.1 MPa, 3.6 ± 0.6 MPa and 3.3 ± 0.2 MPa, respectively). In addition, the strong adhesion to the tissue of this double-layer film is related to the alginate layer. AA can release in a controlled manner, which can significantly promote corneal stroma cells' attachment, alignment, and proliferation compared to the control (AA-free micro-patterned film). Our results reveal that this innovative multifunctional S/G-SA + AA film can be a proper candidate for use in stroma tissue engineering of the human cornea.


Assuntos
Materiais Biocompatíveis/química , Engenharia Tecidual/métodos , Alginatos/química , Humanos , Nanofibras/química
15.
Int J Biol Macromol ; 183: 1402-1409, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34019920

RESUMO

The purpose of this study was to further improve the physiochemical stability of the chitosan (CS) particle-stabilized Pickering emulsion by coating with sodium alginate (SA). The effect of different mass ratios of CS and SA (1:0.5-1:2) on the microstructure, rheology and the stability of the emulsions were comprehensively evaluated by various methods such as optical microscope, scanning electron microscope, rheometer, and low-field nuclear magnetism. The multilayer emulsion with low content of SA (CS:SA = 1:0.5) presented bridging flocculation. If SA concentration was high (CS:SA = 1:1-1:2), the surface of the Pickering emulsion droplets was completely covered by the SA. At this time, multilayer emulsion droplets became stable due to strong electrostatic and/or steric repulsion. Too high SA concentration (CS:GA = 1:2) might also promote the accumulation of moisture. In addition, the CS/SA multilayer emulsion showed higher coalescence stability under different environmental treatments but its creaming stability and flocculation stability were still sensitive to pH (2, 4 and 10), temperature (4 °C and 80 °C) and ionic strength (300-500 mM). In all, the addition of the proper level SA (CS:GA = 1:1-1:2) could increase the stability of CS particle-stabilized Pickering emulsion.


Assuntos
Alginatos/química , Quitosana/química , Emulsões/química , Reologia
16.
Int J Biol Macromol ; 182: 1362-1370, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33965493

RESUMO

This study attempted to prepare ternary conjugate emulsion from bovine serum albumin (BSA), dextran (DEX) and gallic acid (GA) to improve the stability of conjugate emulsion and the bioaccessibility of capsorubin. The release of capsorubin was further delayed by sodium alginate capsules in the intestinal phase. First, protein formed new functional groups and covalent bonds was analyzed by Fourier transform infrared (FTIR) and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Next, the stability of the ternary conjugate showed distinct pH correlation and the higher stability near the isoelectric point. Finally, the bioaccessibility of capsorubin embedded in sodium alginate emulsion was higher than that of ternary conjugate emulsion (65% and 34%).


Assuntos
Alginatos/química , Dextranos/química , Ácido Gálico/química , Soroalbumina Bovina/química , Xantofilas/metabolismo , Animais , Antioxidantes/farmacologia , Disponibilidade Biológica , Digestão/efeitos dos fármacos , Emulsões/química , Trato Gastrointestinal/fisiologia , Concentração de Íons de Hidrogênio , Luz , Suínos , Temperatura
17.
Int J Biol Macromol ; 182: 1339-1350, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34000316

RESUMO

Surgical resection of the tumor remains the preferred treatment for most solid tumors at an early stage, but surgical treatment often leads to massive bleeding and residual tumor cells. Therefore, a novel alginate/gelatin sponge combined with curcumin-loaded electrospun fibers (CFAGS) for rapid hemostasis and prevention of tumor recurrence was prepared by using an electrospinning and interpenetrating polymer network (IPN) strategy. The present results show that alginate/gelatin sponge display excellent hemostatic properties and possess more advantages than commercial gelatin hemostasis sponge. More importantly, CFAGS could control the release of curcumin, inducing curcumin to accumulate at the surgical site of the tumor, thereby inhibiting local tumor recurrence in the subcutaneous postoperative recurrence model. In addition, the sponge was safe to implant in the body and did not cause toxicity to normal tissues and organs. This approach represents a new strategy to implant a dual functional sponge at the postoperative site as an adjuvant to the surgical treatment of cancer.


Assuntos
Alginatos/química , Curcumina/farmacologia , Gelatina/química , Hemostasia/efeitos dos fármacos , Recidiva Local de Neoplasia/prevenção & controle , Cuidados Pós-Operatórios , Animais , Morte Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Fluorescência , Humanos , Células MCF-7 , Masculino , Recidiva Local de Neoplasia/patologia , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
18.
Int J Biol Macromol ; 182: 1863-1873, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34058207

RESUMO

To improve the controlled release and stability of the loaded drug, the alginate-porous starch solution, as the gel matrix (GM), was prepared and added into curcumin-loaded microemulsion (CUR-ME) in a certain proportion, and then mixed with slow-gelling agents (CaCO3 + d-glucono-δ-lactone) to prepared curcumin-loaded microemulsion gel (CUR-ME-G). With increasing the proportion of GM from 25% (CUR-ME3G1) to 83% (CUR-ME1G5), the drug loading efficiency increased from 24% to 98% and the maximum drug loading capacity (14.9 mg/g) was found in CUR-ME1G3 with 75% GM. Moreover, a denser structure that entrapped all microemulsion droplets was formed with increasing the proportion of microemulsion according to the observation of scanning electron microscopy. This was also confirmed by Fourier transform infrared spectroscopy and Raman spectroscopy that no new peaks appeared in CUR-ME-G, while the hydrogen bonding interactions might exist between curcumin and sodium alginate. The in vitro release of the CUR-ME-G followed diffusion-controlled mechanism that was consistent with the first-order kinetic model. The release rate depended on the components of the CUR-ME-G and the pH value of the release medium. CUR-ME-G with curcumin concentration of 0.20% exhibited the best biological activity. CUR-ME-G might provide a potential application in the smart drug delivery systems.


Assuntos
Alginatos/química , Curcumina/farmacologia , Emulsões/química , Géis/química , Amido/química , Anti-Infecciosos/farmacologia , Compostos de Bifenilo/química , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Sequestradores de Radicais Livres/química , Dureza , Concentração de Íons de Hidrogênio , Cinética , Testes de Sensibilidade Microbiana , Picratos/química , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Staphylococcus aureus/efeitos dos fármacos , Temperatura , Difração de Raios X
19.
Int J Biol Macromol ; 183: 423-434, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33932415

RESUMO

In this study, Lactobacillus reuteri B2 was isolated from the feces of C57BL/6 mice and assessed on probiotic activity. L. reuteri B2 was identified by 16S rDNA sequencing, which the cell viability in acidic conditions at pH 2.0 was 64% after 2 h, and in the presents of 0.30% of the bile salts, after 6 h, was 37%. Antimicrobial assay with L. reuteri B2 showed maximum diameters against Klebsiela oxytoca J7 (12.5 ± 0.71 mm). We further hypothesized if L. reuteri B2 strain in the free form can survive all conditions in the gastrointestinal tract (GIT) then the utilization of the appropriate biomaterials would ameliorate its stability and viability in GIT. L. reuteri B2 was microencapsulated into sodium alginate-(Na-alg) and different content of Na-alg and sodium maleate (SM) beads. Characterization materials enveloped their thermal characteristics (TGA/DTA analysis) and structure using: scanning electron microscopy (SEM), FTIR, and particle size distribution. The high survival rate of L. reuteri B2 at low pH from 2.0 to 4.0 and in the presence of the bile salts, at concentrations up to 0.30%, was obtained. L. reuteri B2 showed strong antimicrobial activity and the best protection microencapsulated with Na-alg + SM in simulated gastric juices (SGJ).


Assuntos
Alginatos/química , Biopolímeros/química , DNA Ribossômico/metabolismo , Lactobacillus reuteri/metabolismo , Probióticos/uso terapêutico
20.
Int J Biol Macromol ; 183: 564-588, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33933542

RESUMO

Biofabrication by three-dimensional (3D) printing has been an attractive technology in harnessing the possibility to print anatomical shaped native tissues with controlled architecture and resolution. 3D printing offers the possibility to reproduce complex microarchitecture of native tissues by printing live cells in a layer by layer deposition to provide a biomimetic structural environment for tissue formation and host tissue integration. Plant based biomaterials derived from green and sustainable sources have represented to emulate native physicochemical and biological cues in order to direct specific cellular response and formation of new tissues through biomolecular recognition patterns. This comprehensive review aims to analyze and identify the most commonly used plant based bioinks for 3D printing applications. An overview on the role of different plant based biomaterial of terrestrial origin (Starch, Nanocellulose and Pectin) and marine origin (Ulvan, Alginate, Fucoidan, Agarose and Carrageenan) used for 3D printing applications are discussed elaborately. Furthermore, this review will also emphasis in the functional aspects of different 3D printers, appropriate printing material, merits and demerits of numerous plant based bioinks in developing 3D printed tissue-like constructs. Additionally, the underlying potential benefits, limitations and future perspectives of plant based bioinks for tissue engineering (TE) applications are also discussed.


Assuntos
Nanocompostos , Polissacarídeos/química , Impressão Tridimensional/tendências , Medicina Regenerativa/tendências , Engenharia Tecidual/tendências , Alginatos/química , Animais , Carragenina/química , Celulose/química , Difusão de Inovações , Previsões , Humanos , Pectinas/química , Sefarose/química
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