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1.
Environ Monit Assess ; 193(6): 328, 2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-33956244

RESUMEN

Petroleum contamination of marine environments due to exploitation and accidental spills causes serious harm to ecosystems. Bioremediation with immobilized microorganisms is an environmentally friendly and cost-effective emerging technology for treating oil-polluted environments. In this study, Bacillus licheniformis was entrapped in Ca alginate beads using the electrospray technique for light crude oil biodegradation. Three important process variables, including inoculum size (5-15% v/v), initial oil concentration (1500-3500 ppm), and NaCl concentration (0-30 g/L), were optimized to obtain the best response of crude oil removal using response surface methodology (RSM) and Box-Behnken design (BBD). The highest crude oil removal of 79.58% was obtained for 1500 ppm of crude oil after 14 days using immobilized cells, and it was lower for freely suspended cells (64.77%). Our result showed similar trends in the effect of variables on the oil biodegradation rate in both free cell (FC) and immobilized cell (IC) systems. However, according to the analysis of variance (ANOVA) results, the extent of the variables' effectiveness was different in FC and IC systems. In the immobilized cell system, all variables had a greater effect on the rate of light crude oil degradation. Moreover, to evaluate the effectiveness of free and immobilized B. licheniformis in bioremediation of an actual polluted site, the crude oil spill in natural seawater was investigated. The results suggested the stability of beads in the seawater, as well as high degradation of petroleum hydrocarbons by free and immobilized cells in the presence of indigenous microorganisms.


Asunto(s)
Bacillus licheniformis , Contaminación por Petróleo , Petróleo , Alginatos , Biodegradación Ambiental , Ecosistema , Monitoreo del Ambiente , Petróleo/análisis , Contaminación por Petróleo/análisis , Agua de Mar
2.
J Environ Manage ; 289: 112506, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33831760

RESUMEN

Polyelectrolyte composite nanospheres are relatively new adsorbents which have attracted much attention for their efficient pollutant removal and reuse performance. A novel polyelectrolyte nanosphere with magnetic function (SA@AM) was synthesized via the electrostatic reaction between the polyanionic sodium alginate (SA) and the surface of a prepared terminal amino-based magnetic nanoparticles (AMs). SA@AM showed a size of 15-22 nm with 6.85 emu·g-1 of magnetization value, exhibiting a high adsorption capacity on Pb(II) ions representing a common heavy metal pollutant, with a maximum adsorption capacity of 105.8 mg g-1. The Langmuir isotherm adsorption fits the adsorption curve, indicating uniform adsorption of Pb(II) on the SA@AM surfaces. Repeated adsorption desorption experiments showed that the removal ratio of Pb(II) by SA@AM was more than 76%, illustrating improved regeneration performance. These results provide useful information for the production of bio-based green magnetic nano scale adsorption materials for environmental remediation applications.


Asunto(s)
Nanosferas , Contaminantes Químicos del Agua , Adsorción , Alginatos , Concentración de Iones de Hidrógeno , Iones , Cinética , Plomo , Fenómenos Magnéticos , Polielectrolitos , Aguas Residuales , Contaminantes Químicos del Agua/análisis
3.
AAPS PharmSciTech ; 22(3): 123, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33821421

RESUMEN

Fruit juices are successfully proposed as suitable probiotic vehicles, but researchers' efforts should be developed to avoid effects of bacteria overgrowing on sensory and nutritional cues of final products and to preserve viability of probiotic bacteria during storage. In the present study, encapsulation of Lacticaseibacillus rhamnosus GG strain in alginate systems was performed through ionotropic gelation technology. The alginate systems were optimized by using Box-Behnken Design to investigate the influence of three independent variables at three different levels: particle mean size and polydispersity index. The optimized probiotic-loaded alginate particles were added to orange juice samples. The viability of the probiotic strain, both as free and microencapsulated, was evaluated in orange juice stored at 5°C for 35 days. Morphology and size of probiotic-loaded alginate particles were found suitable for incorporation into juice. TEM analysis revealed that unloaded systems were clustered as nanoparticles (CL_NP), while the loaded sample appeared as a coated system (Coated_LGG). Microbiological evaluation revealed that the encapsulation assured the survival of Coated_LGG, with a reduction of less than 1-unit log in cellular density after 35 days of refrigerated storage in orange juice. Results indicated that the encapsulated bacteria did not affect the macroscopic properties neither the microbiological characteristic of orange juice; thus, it can be proposed as functional food.


Asunto(s)
Alginatos/química , Citrus sinensis , Jugos de Frutas y Vegetales/microbiología , Lactobacillus casei , Probióticos/administración & dosificación , Alimentos Funcionales/análisis , Viabilidad Microbiana , Nanopartículas , Tamaño de la Partícula , Vehículos Farmacéuticos
4.
Int J Mol Sci ; 22(5)2021 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-33800824

RESUMEN

A new copper complex, trans-diaqua-trans-bis [1-hydroxy-1,2-di (methoxycarbonyl) ethenato] copper (abbreviation Cu(II) complex), was synthesized and its plant growth regulation properties were investigated. The results show a sharp dependence of growth regulation activity of the Cu(II) complex on the type of culture and its concentration. New plant growth regulator accelerated the development of the corn root system (the increase in both length and weight) but showed a smaller effect on the development of the wheat and barley root systems. Stimulation of corn growth decreased with increasing Cu(II) complex concentration from 0.0001% to 0.01% (inhibition at high concentrations-0.01%). The development of corn stems was also accelerated but to a lesser extent. Chitosan-coated calcium alginate microcapsules suitable for delivery of Cu(II) complex to plants were prepared and characterized. Analysis of the FTIR spectrum showed that complex molecular interactions between functional groups of microcapsule constituents include mainly electrostatic interactions and hydrogen bonds. Microcapsules surface exhibits a soft granular surface structure with substructures consisting of abundant smaller particles with reduced surface roughness. Release profile analysis showed Fickian diffusion is the rate-controlling mechanism of Cu(II) complex releasing. The obtained results give new insights into the complexity of the interaction between the Cu(II) complex and microcapsule formulation constituents, which can be of great help in accelerating product development for the application in agriculture.


Asunto(s)
Alginatos/administración & dosificación , Quitosano/administración & dosificación , Portadores de Fármacos/administración & dosificación , Composición de Medicamentos/métodos , Reguladores del Crecimiento de las Plantas/síntesis química , Rastreo Diferencial de Calorimetría , Cápsulas , Difusión , Portadores de Fármacos/química , Germinación/efectos de los fármacos , Enlace de Hidrógeno , Microscopía Electrónica de Rastreo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Tallos de la Planta/efectos de los fármacos , Tallos de la Planta/crecimiento & desarrollo , Poaceae/efectos de los fármacos , Poaceae/crecimiento & desarrollo , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Propiedades de Superficie
5.
Int J Mol Sci ; 22(6)2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33809794

RESUMEN

In recent years, a major rise in the demand for biotherapeutic drugs has centered on enhancing the quality and efficacy of cell culture and developing new cell culture techniques. Here, we report fibronectin (FN) derived, novel peptides fibronectin-based intergrin binding peptide (FNIN)2 (18-mer) and FNIN3 (20-mer) which promote cell adhesion proliferation, and the differentiation of primary cells and stem cells. FNIN2 and 3 were designed based on the in silico interaction studies between FN and its receptors (integrin α5ß1, αvß3, and αIIbß3). Analysis of the proliferation of seventeen-cell types showed that the effects of FNINs depend on their concentration and the existence of expressed integrins. Significant rhodamine-labeled FNIN2 fluorescence on the membranes of HeLa, HepG2, A498, and Du145 cells confirmed physical binding. Double coating with FNIN2 or 3 after polymerized dopamine (pDa) or polymerized tannic acid (pTA) precoating increased HBEpIC cell proliferation by 30-40 percent, suggesting FNINs potently affect primary cells. Furthermore, the proliferation of C2C12 myoblasts and human mesenchymal stem cells (MSCs) treated with FNINs was significantly increased in 2D/3D culture. FNINs also promoted MSC differentiation into osteoblasts. The results of this study offer a new approach to the production of core materials (e.g., cell culture medium components, scaffolds) for cell culture.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Fibronectinas/química , Células Madre Mesenquimatosas/citología , Péptidos/farmacología , Alginatos , Animales , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Células HeLa , Humanos , Integrinas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Ratones , Modelos Moleculares , Osteogénesis/efectos de los fármacos , Dominios Proteicos , Ratas , Receptores de Superficie Celular/metabolismo
6.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-33805785

RESUMEN

Osteoporosis is a worldwide chronic disease characterized by increasing bone fragility and fracture likelihood. In the treatment of bone defects, materials based on calcium phosphates (CaPs) are used due to their high resemblance to bone mineral, their non-toxicity, and their affinity to ionic modifications and increasing osteogenic properties. Moreover, CaPs, especially hydroxyapatite (HA), can be successfully used as a vehicle for local drug delivery. Therefore, the aim of this work was to fabricate hydroxyapatite-based composite beads for potential use as local carriers for raloxifene. HA powder, modified with magnesium and silicon ions (Mg,Si-HA) (both of which play beneficial roles in bone formation), was used to prepare composite beads. As an organic matrix, sodium alginate with chondroitin sulphate and/or keratin was applied. Cross-linking of beads containing raloxifene hydrochloride (RAL) was carried out with Mg ions in order to additionally increase the concentration of this element on the material surface. The morphology and porosity of three different types of beads obtained in this work were characterized by scanning electron microscopy (SEM) and mercury intrusion porosimetry, respectively. The Mg and Si released from the Mg,Si-HA powder and from the beads were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). In vitro RAL release profiles were investigated for 12 weeks and studied using UV/Vis spectroscopy. The beads were also subjected to in vitro biological tests on osteoblast and osteosarcoma cell lines. All the obtained beads revealed a spherical shape with a rough, porous surface. The beads based on chondroitin sulphate and keratin (CS/KER-RAL) with the lowest porosity resulted in the highest resistance to crushing. Results revealed that these beads possessed the most sustained drug release and no burst release effect. Based on the results, it was possible to select the optimal bead composition, consisting of a mixture of chondroitin sulphate and keratin.


Asunto(s)
Alginatos/química , Conservadores de la Densidad Ósea/farmacología , Sistemas de Liberación de Medicamentos/métodos , Durapatita/química , Silicatos de Magnesio/química , Clorhidrato de Raloxifeno/farmacología , Conservadores de la Densidad Ósea/metabolismo , Regeneración Ósea/fisiología , Huesos/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sulfatos de Condroitina/química , Liberación de Fármacos , Humanos , Queratinas/química , Cinética , Nanopartículas/química , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Porosidad , Clorhidrato de Raloxifeno/metabolismo
7.
Front Cell Infect Microbiol ; 11: 641920, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33816347

RESUMEN

Pseudomonas aeruginosa is a biofilm-forming opportunistic pathogen which causes chronic infections in immunocompromised patients and leads to high mortality rate. It is identified as a common coinfecting pathogen in COVID-19 patients causing exacerbation of illness. In our hospital, P. aeruginosa is one of the top coinfecting bacteria identified among COVID-19 patients. We collected a strong biofilm-forming P. aeruginosa strain displaying small colony variant morphology from a severe COVID-19 patient. Genomic and transcriptomic sequencing analyses were performed with phenotypic validation to investigate its adaptation in SARS-CoV-2 infected environment. Genomic characterization predicted specific genomic islands highly associated with virulence, transcriptional regulation, and DNA restriction-modification systems. Epigenetic analysis revealed a specific N6-methyl adenine (m6A) methylating pattern including methylation of alginate, flagellar and quorum sensing associated genes. Differential gene expression analysis indicated that this isolate formed excessive biofilm by reducing flagellar formation (7.4 to 1,624.1 folds) and overproducing extracellular matrix components including CdrA (4.4 folds), alginate (5.2 to 29.1 folds) and Pel (4.8-5.5 folds). In summary, we demonstrated that P. aeuginosa clinical isolates with novel epigenetic markers could form excessive biofilm, which might enhance its antibiotic resistance and in vivo colonization in COVID-19 patients.


Asunto(s)
Adaptación Fisiológica/fisiología , Coinfección/complicaciones , Infecciones por Pseudomonas/complicaciones , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/metabolismo , Alginatos , Bacterias , Biopelículas/crecimiento & desarrollo , Metilación de ADN , Epigenómica , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Genoma Bacteriano , Humanos , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/clasificación , Percepción de Quorum/genética , Transcriptoma , Virulencia
8.
Int J Mol Sci ; 22(6)2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33803546

RESUMEN

Alginate as a versatile naturally occurring biomaterial has found widespread use in the biomedical field due to its unique features such as biocompatibility and biodegradability. The ability of its semipermeable hydrogels to provide a favourable microenvironment for clinically relevant cells made alginate encapsulation a leading technology for immunoisolation, 3D culture, cryopreservation as well as cell and drug delivery. The aim of this work is the evaluation of structural properties and swelling behaviour of the core-shell capsules for the encapsulation of multipotent stromal cells (MSCs), their 3D culture and cryopreservation using slow freezing. The cells were encapsulated in core-shell capsules using coaxial electrospraying, cultured for 35 days and cryopreserved. Cell viability, metabolic activity and cell-cell interactions were analysed. Cryopreservation of MSCs-laden core-shell capsules was performed according to parameters pre-selected on cell-free capsules. The results suggest that core-shell capsules produced from the low viscosity high-G alginate are superior to high-M ones in terms of stability during in vitro culture, as well as to solid beads in terms of promoting formation of viable self-assembled cellular structures and maintenance of MSCs functionality on a long-term basis. The application of 0.3 M sucrose demonstrated a beneficial effect on the integrity of capsules and viability of formed 3D cell assemblies, as compared to 10% dimethyl sulfoxide (DMSO) alone. The proposed workflow from the preparation of core-shell capsules with self-assembled cellular structures to the cryopreservation appears to be a promising strategy for their off-the-shelf availability.


Asunto(s)
Alginatos/química , Hidrogeles/química , Andamios del Tejido/química , Animales , Callithrix , Cápsulas , Supervivencia Celular , Criopreservación , Dermis/citología , Humanos , Células Madre Mesenquimatosas/citología , Tamaño de la Partícula , Espectrometría Raman , Factores de Tiempo , Agua/química
9.
Bioresour Technol ; 331: 125065, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33819908

RESUMEN

The co-existence of nitrate, manganese (Mn), and antibiotics are of a wide concern. In this study, a denitrifying and manganese-oxidizing Zoogloea Q7 bacterium was immobilized using polyvinyl alcohol/sodium alginate with sponge cube (PVA/SA@sponge cube) in the reactor. The optimal operation parameters of the bioreactor were explored. Maximum nitrate, Mn(II), and tetracycline (TC) removal efficiencies of 93.00, 72.34, and 57.32% were achieved with HRT of 10 h, pH of 6.5, Mn(II) concentration of 20 mg L-1, and TC of 1 mg L-1, respectively. Fluorescence excitation-emission matrix (EEM) proved that the microorganism in the bioreactor was greatly active. Scanning electron microscope (SEM) images demonstrated that Zoogloea Q7 was commendably immobilized on the novel material. X-ray diffraction (XRD) analysis suggested that the bioprecipitate was mainly composed of MnO2 and MnCO3. Through high-throughput analysis, Zoogloea sp. Q7 was considered to be the dominant bacteria present in the bioreactor.


Asunto(s)
Nitratos , Alcohol Polivinílico , Alginatos , Antibacterianos , Reactores Biológicos , Desnitrificación , Manganeso , Compuestos de Manganeso , Óxidos
10.
Bioresour Technol ; 331: 125046, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33827016

RESUMEN

A FeCl3-activated seaweed carbon/MCM-41/alginate hydrogel composite (ECAC/MCM-41/ ALG) cross-linked with calcium chloride (2% CaCl2) was synthesized for the biosorption of bisphenol A (BPA) plasticizer and basic blue (BB) dye. Biosorption uptakes of BPA and BB were performed in a batch mode with varying solution pH from 3 to 11, initial sorbate concentration from 25 to 300 mg/L, reaction time from 0 to 10 h, and biosorption temperature from 30 to 50 °C. The maximum BPA and BB uptake mechanisms were fast, which occurred within contact times of 1 and 2 h with monolayer coverage capacities of 222.32 and 190.11 mg/g at 50 °C, respectively. Cyclic biosorption/desorption behavior was evaluated via an ethanol elution to evaluate the feasibility of the ECAC/MCM-41/ALG for long-term application. Results revealed the biosorption renewability for five cycles up to 80% of the newly synthesized hydrogel composite for the purification of industrial wastewater laden with emerging contaminants.


Asunto(s)
Algas Marinas , Contaminantes Químicos del Agua , Adsorción , Alginatos , Compuestos de Bencidrilo , Hidrogeles , Concentración de Iones de Hidrógeno , Cinética , Fenoles , Plastificantes , Dióxido de Silicio , Termodinámica
11.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33801871

RESUMEN

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


Asunto(s)
Preparaciones de Acción Retardada/farmacocinética , Nanopartículas/química , Preparaciones Farmacéuticas/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacocinética , Alginatos/química , Biodegradación Ambiental , Cápsulas , Quitosano/química , Preparaciones de Acción Retardada/química , Portadores de Fármacos , Liberación de Fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo , Microesferas , Nanopartículas/ultraestructura , Tamaño de la Partícula , Preparaciones Farmacéuticas/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química
12.
J Dairy Sci ; 104(5): 5279-5284, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33663820

RESUMEN

Camel milk (CM) is gaining scientific attention due to its potential health and therapeutic benefits. Fermented drinkable yogurts (labans) were prepared from CM and bovine milk (BM) using mixed Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus bacteria supplemented with 1 of 2 hydrocolloids: pectin (0.1-0.3%) or sodium alginate (0.1-0.5%). The different labans were compared by studying their acidity and rheology as well as their structural and sensory properties. The CM and BM labans had titratable acidity values that ranged from 0.85 to 1.27 and 0.61 to 0.93%, respectively. Pectin at 0.2% enhanced the rheological properties of BM labans, but had no effect in CM labans. Sodium alginate at 0.3% and 0.5% increased viscosity, elastic or storage modulus (G'), and viscous or loss modulus (G″) values for both types of laban. Scanning electron microscopy indicated that the CM laban contained lower levels of "spike-like structures" than BM laban, and that the addition of hydrocolloids improved this effect. Quantitative descriptive sensory analysis showed that CM labans fortified with either 0.2% pectin or 0.3% sodium alginate were comparable to commercial BM laban in viscous mouthfeel. Fortified CM labans were more acidic and had stronger flavors than unfortified samples. Overall, this study demonstrated that the addition of sodium alginate or pectin at intermediate levels permits production of palatable CM labans of a satisfactory viscous consistency.


Asunto(s)
Camelus , Leche , Alginatos , Animales , Bovinos , Fermentación , Pectinas , Streptococcus thermophilus , Yogur
13.
Int J Mol Sci ; 22(4)2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33669209

RESUMEN

Nisin Z, an amphipathic peptide, with a significant antibacterial activity against Gram-positive bacteria and low toxicity in humans, has been studied for food preservation applications. Thus far, very little research has been done to explore its potential in biomedicine. Here, we report the modification of sodium alginate (SA) and gelatin (GN) blended microfibers, produced via the wet-spinning technique, with Nisin Z, with the purpose of eradicating Staphylococcus aureus-induced infections. Wet-spun SAGN microfibers were successfully produced at a 70/30% v/v of SA (2 wt%)/GN (1 wt%) polymer ratio by extrusion within a calcium chloride (CaCl2) coagulation bath. Modifications to the biodegradable fibers' chemical stability and structure were then introduced via crosslinking with CaCl2 and glutaraldehyde (SAGNCL). Regardless of the chemical modification employed, all microfibers were labelled as homogeneous both in size (≈246.79 µm) and shape (cylindrical and defect-free). SA-free microfibers, with an increased surface area for peptide immobilization, originated from the action of phosphate buffer saline solution on SAGN fibers, were also produced (GNCL). Their durability in physiological conditions (simulated body fluid) was, however, compromised very early in the experiment (day 1 and 3, with and without Nisin Z, respectively). Only the crosslinked SAGNCL fibers remained intact for the 28 day-testing period. Their thermal resilience in comparison with the unmodified and SA-free fibers was also demonstrated. Nisin Z was functionalized onto the unmodified and chemically altered fibers at an average concentration of 178 µg/mL. Nisin Z did not impact on the fiber's morphology nor on their chemical/thermal stability. However, the peptide improved the SA fibers (control) structural integrity, guaranteeing its stability for longer, in physiological conditions. Its main effect was detected on the time-kill kinetics of the bacteria S. aureus. SAGNCL and GNCL loaded with Nisin Z were capable of progressively eliminating the bacteria, reaching an inhibition superior to 99% after 24 h of culture. The peptide-modified SA and SAGN were not as effective, losing their antimicrobial action after 6 h of incubation. Bacteria elimination was consistent with the release kinetics of Nisin Z from the fibers. In general, data revealed the increased potential and durable effect of Nisin Z (significantly superior to its free, unloaded form) against S. aureus-induced infections, while loaded onto prospective biomedical wet-spun scaffolds.


Asunto(s)
Alginatos/química , Antibacterianos/química , Antibacterianos/farmacología , Reactivos de Enlaces Cruzados/química , Gelatina/química , Nisina/análogos & derivados , Staphylococcus aureus/efectos de los fármacos , Materiales Biocompatibles/química , Plásticos Biodegradables/química , Biopolímeros/química , Cloruro de Calcio/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Glutaral/química , Cinética , Pruebas de Sensibilidad Microbiana , Nisina/química , Nisina/farmacología , Porosidad , Solubilidad , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Agua/química
14.
Int J Mol Sci ; 22(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652991

RESUMEN

A hydrogel system based on oxidized alginate covalently crosslinked with gelatin (ADA-GEL) has been utilized for different biofabrication approaches to design constructs, in which cell growth, proliferation and migration have been observed. However, cell-bioink interactions are not completely understood and the potential effects of free aldehyde groups on the living cells have not been investigated. In this study, alginate, ADA and ADA-GEL were characterized via FTIR and NMR, and their effect on cell viability was investigated. In the tested cell lines, there was a concentration-dependent effect of oxidation degree on cell viability, with the strongest cytotoxicity observed after 72 h of culture. Subsequently, primary human cells, namely fibroblasts and endothelial cells (ECs) were grown in ADA and ADA-GEL hydrogels to investigate the molecular effects of oxidized material. In ADA, an extremely strong ROS generation resulting in a rapid depletion of cellular thiols was observed in ECs, leading to rapid necrotic cell death. In contrast, less pronounced cytotoxic effects of ADA were noted on human fibroblasts. Human fibroblasts had higher cellular thiol content than primary ECs and entered apoptosis under strong oxidative stress. The presence of gelatin in the hydrogel improved the primary cell survival, likely by reducing the oxidative stress via binding to the CHO groups. Consequently, ADA-GEL was better tolerated than ADA alone. Fibroblasts were able to survive the oxidative stress in ADA-GEL and re-entered the proliferative phase. To the best of our knowledge, this is the first report that shows in detail the relationship between oxidative stress-induced intracellular processes and alginate di-aldehyde-based bioinks.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Células Endoteliales/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Gelatina/química , Estrés Oxidativo/efectos de los fármacos , Alginatos/toxicidad , Animales , Materiales Biocompatibles/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células Endoteliales/citología , Fibroblastos/citología , Gelatina/toxicidad , Humanos , Ratones , Células 3T3 NIH , Andamios del Tejido/química
15.
Carbohydr Polym ; 260: 117793, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712141

RESUMEN

The present study demonstrates the extrusion printing of highly viscous and thixotropic hydroxyethylcellulose-based bioinks blended with various concentrations of sodium alginate (SA) and embedded with HeLa cells. The cell viability is shown to be inversely proportional to the relative SA content and can be as high as 81.5 % following one day of incubation. Furthermore, the biocompatibility of the hydrogel matrix supports cell proliferation resulting in an order of magnitude larger number of cells after a 7-day incubation. The cell viability is negatively affected mostly by the extrusion printing itself with some cell death occurring during their embedding in the hydrogels. After embedding the HeLa cells in the blends containing 1 and 2.5 % SA, the cell viability is not significantly affected by the residence time of up to 90 min before the bioink extrusion. The printed constructs can be utilized as a cervical tumor model.


Asunto(s)
Bioimpresión , Celulosa/análogos & derivados , Alginatos/química , Supervivencia Celular/efectos de los fármacos , Celulosa/química , Femenino , Células HeLa , Humanos , Hidrogeles/química , Hidrogeles/farmacología , Tinta , Paclitaxel/química , Paclitaxel/farmacología , Reología , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología
16.
Carbohydr Polym ; 260: 117827, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712167

RESUMEN

Alginates, a kind of naturally occurring polysaccharides, have been exploited for functional materials owing to their versatility, sustainability, nontoxicity, and relatively low cost. Inherent flame retardancy is one of the most attractive features of alginates, as it enables the high-value-added utilization of alginates for eco-friendly flame-retardant materials. Now, the influence of metal ions on the flame retardancy and pyrolysis behaviors of alginates has been systematically studied; besides, the applications of alginates for flame-retardant materials have been greatly developed, such as for preparing flame-retardant fibers, fabrics, aerogel composites, and foams, as well as serving as a component or modifier of functional coatings, hybrids, and additives. This review will give an overview of the recent progress and the prospects of using alginates in flame-retardant fields, which can guide the design of bio-based flame retardants and benefit the further development of more diverse applications of alginates.


Asunto(s)
Alginatos/química , Retardadores de Llama/análisis , Geles/química , Metales/química , Polímeros/química , Pirólisis , Viscosidad
17.
Food Chem ; 352: 129220, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33684717

RESUMEN

Cationic antimicrobial peptides have raised interest as attractive alternatives to classical antibiotics, and also have utility in preventing food spoilage. We set out to enrich cationic antimicrobial peptides from milk hydrolysates using gels containing various ratios of anionic pectin/alginate. All processes were carried out with food-grade materials in order to suggest food-safe methods suited for producing food ingredients or supplements. Hydrolysed caseinate peptides retained in the gel fraction, identified by mass spectrometry, were enriched for potential antimicrobial peptides, as judged by a computational predictor of antimicrobial activity. Peptides retained in a 60:40 pectin:alginate gel fraction had a strong antimicrobial effect against 8 tested bacterial strains with a minimal inhibitory concentration of 1.5-5 mg/mL, while the unfractionated hydrolysate only had a detectable effect in one of the eight strains. Among 110 predicted antimicrobial peptides in the gel fraction, four are known antimicrobial peptides, HKEMPFPK, TTMPLW, YYQQKPVA and AVPYPQR. These results highlight the potential of pectin/alginate food-gels based processes as safe, fast, cost-effective methods to separate and enrich for antimicrobial peptides from complex food protein hydrolysates.


Asunto(s)
Alginatos/química , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Leche/química , Pectinas/química , Hidrolisados de Proteína/química , Secuencia de Aminoácidos , Animales , Geles , Pruebas de Sensibilidad Microbiana
18.
Food Chem ; 352: 129325, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691212

RESUMEN

The milk-coagulating enzyme, rennet, is widely used in cheese making. Recently stabilization of rennet, especially in accelerated cheese ripening, has received considerable interest. As we know encapsulation is one of the enzyme immobilization methods, which could increase enzyme stability. In this study, the effects of alginate, chitosan and, CaCl2 on rennet encapsulation were evaluated and optimized using RSM. Under the optimal conditions alginate, chitosan, and CaCl2 were 0.04%, 0.1%, and 0.1% respectively. At the optimum point, encapsulation efficiency, particle size, and zeta potential were evaluated to be 61.8%, 323 nm, and 25 mV, respectively. The effect of temperature and pH on the enzyme activity was evaluated, and the results showed that encapsulated enzyme had higher activity at various pH and temperature in comparison with the free enzyme. Also, the enzyme release data in all pH values were fitted to Korsmeyer-Peppas model and the n exponent indicated that the release mechanism was Fickian. The electrostatic interactions between enzyme, alginate, and chitosan were confirmed by infrared spectroscopy. No statistical difference was found between the Km and Vmax of encapsulated and free enzymes.


Asunto(s)
Alginatos/química , Quitosano/química , Quimosina/química , Enzimas Inmovilizadas/química , Nanopartículas/química , Cloruro de Calcio/química , Tamaño de la Partícula
19.
Carbohydr Polym ; 260: 117774, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712131

RESUMEN

3D printing, one of its kinds has been a recent technological trend to fabricate complex and patterned biomaterial with controlled precision. With the conventional kick-start of printing metals and plastics, advancements in printing viable cells, polysaccharides or microbes themselves have been achieved. The additive antimicrobial properties in bioinks sourced from organic and inorganic materials have profound implications in tissue engineering. Cellulose, alginate, exopolysaccharides, ceramics and synthetic polymers are integrated as a viable component in inks and used for bio-printing. To date, bacterial infection and immunogenicity pose a potential health risk during a tissue implant or bone substitution. In order to mitigate microbial infection, antimicrobial bioinks with significant antimicrobial potential have been the much sought after strategies. This approach could be an effective frontline defense against microbial interference in tissue engineering and biomedical applications. An overview on the antimicrobial potential of polysaccharides as bioinks for 3D bioprinting has been critically reviewed.


Asunto(s)
Antiinfecciosos/química , Bioimpresión , Tinta , Alginatos/química , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Celulosa/química , Hongos/efectos de los fármacos , Polímeros/química , Polisacáridos Bacterianos/química , Impresión Tridimensional
20.
Carbohydr Polym ; 260: 117777, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712133

RESUMEN

The combination of alginate, hyaluronic acid and multivalent ions have been reported to form alginate-hyaluronic acid ionic-crosslinking hydrogels for biomedical applications. However, injectable alginate-hyaluronic acid ionic-crosslinking hydrogels with satisfactory shear-thinning property have rarely been reported. In this study, we successfully developed an ionic-crosslinked alginate-hyaluronic acid hydrogel by simple assembly of alginate-hyaluronic acid mixture and Fe3+ complex. This hydrogel could fully recover within seconds after damaged, while displayed shear thinning behavior and good injectability which were contributed by the reversible and dynamic metal-ligand interactions formed via ferric ions and carboxyl groups of the polymers. Moreover, the local degradation of this hydrogel giving the hydrogel sustained ferric ions release property, of which led to potential long-term antibacterial activities against multiple types of bacteria including gram-negative Escherichia coli and gram-positive Staphylococcus aureus, as well as representative oral pathogenic bacteria Streptococcus mutans and Porphyromonas gingivalis.


Asunto(s)
Alginatos/química , Antiinfecciosos/química , Compuestos Férricos/química , Ácido Hialurónico/química , Hidrogeles/química , Animales , Antiinfecciosos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Femenino , Compuestos Férricos/metabolismo , Humanos , Hidrogeles/farmacología , Ratones , Ratones Endogámicos BALB C , Porphyromonas/efectos de los fármacos , Reología , Piel/efectos de los fármacos , Piel/patología , Staphylococcus aureus/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos
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