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1.
Biol Trace Elem Res ; 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737440

RESUMO

Boron is one of the essential trace elements in animals. Although boron supplementation can enhance immune function and promote cell proliferation, high-dose boron supplementation can negatively affect immune function and inhibit cell proliferation. Furthermore, its action pathway is unknown. In this study, ERK1/2, JNK, and p38MAPK signaling pathways were blocked using specific blockers to investigate the impact of low-dose and high-dose boron on proliferation, apoptosis, and immune function of lymphocytes, and the expression of genes related to cell proliferation and apoptosis in rats. The addition of 0.4 mmol/L boron did not affect the ratio of CD4+/CD8+ T cells (P>0.05), IgG and IFN-γ contents (P>0.05), the proliferation rate of lymphocytes (P>0.05), and mRNA and protein expressions of PCNA (P>0.05) in the spleen after ERK1/2 signal pathway was selectively inhibited. Moreover, the addition of 40 mmol/L boron did not affect the proportion of CD4+ T cells, contents of IgG and cytokines (IL-2 and IL-4), proliferation and apoptosis rates of lymphocytes, and expression of proliferation- and apoptosis-related genes in the spleen. Meanwhile, the addition of 0.4 mmol/l boron increased the ratio of CD4+/CD8+ T cells (P<0.05 or P<0.01), IFN-γ or IgG contents (P<0.05), and the proliferation rate of lymphocytes (P<0.05) in spleen after selective inhibition of JNK or p38MAPK signaling pathways, while the protein expression of Caspase-3 decreased (P<0.05 or P<0.01). Furthermore, 40 mmol/L boron decreased the proportion of lymphocyte subsets, cytokine contents, proliferation rate of lymphocytes, and mRNA and protein expressions of PCNA. In contrast, the mRNA and protein expressions of Caspase-3 and protein expression of Bax were increased. These results indicate that ERK1/2 signaling pathway mainly regulates the effects of low-dose and high-dose boron on proliferation, apoptosis, and immune function of splenic lymphocytes.

2.
Foods ; 12(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37569176

RESUMO

The aim of this work was to study the physical stability and rheological properties of an oil-in-water emulsion stabilized by a konjac glucomannan-whey protein (KGM-WP) mixture at a konjac glucomannan concentration of 0.1-0.5% (w/w) and a whey protein concentration of 1.0-3.0% (w/w). The droplet size, microstructure, stackability, flow behavior, and viscoelastic properties were measured. The experimental results showed that with an increase in KGM and WP concentrations, the droplet size (D4,3) of the emulsion gradually decreased to 12.9 µm, and the macroscopic performance of the emulsion was a gel-like structure that can be inverted and resist flow and can also be extruded and stacked. The static shear viscosity and viscoelasticity generally increased with the increase of konjac glucomannan and whey protein concentration. Emulsions were pseudo-plastic fluids with shear thinning behavior (flow behavior index: 0.15 ≤ n ≤ 0.49) and exhibited viscoelastic behavior with a storage modulus (G') greater than their loss modulus (G″), indicating that the samples all had gel-like behavior (0.10 < n' < 0.22). Moreover, storage modulus and loss modulus of all samples increased with increasing KGM and WP concentrations. When the concentration of konjac glucomannan was 0.3% w/w, the emulsion had similar rheological behavior to commercial mayonnaise. These results suggested that the KGM-WP mixture can be used as an effective substitute for egg yolk to make a cholesterol-free mayonnaise-like emulsion. The knowledge obtained here had important implications for the application of protein-polysaccharide mixtures as emulsifiers/stabilizers to make mayonnaise-like emulsions in sauce and condiments.

3.
Compr Rev Food Sci Food Saf ; 22(1): 587-614, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36529880

RESUMO

Whole flaxseed (flour) as a good source of omega-3 fatty acid and phytochemicals with excellent nutritional and functional attributes has been used to enrich foods for health promotion and disease prevention. However, several limitations and contemporary challenges still impact the development of whole flaxseed (flour)-enriched products on the global market, such as naturally occurring antinutritional factors and entrapment of nutrients within food matrix. Whole flaxseed (flour) with different existing forms could variably alter the techno-functional performance of food matrix, and ultimately affect the edible qualities of fortified food products. The potential interaction mechanism between the subject and object components in fortified products has not been elucidated yet. Hence, in this paper, the physical structure and component changes of flaxseed (flour) by pretreatments coupled with their potential influences on the edible qualities of multiple fortified food products were summarized and analyzed. In addition, several typical food products, including baked, noodle, and dairy products were preferentially selected to investigate the potential influencing mechanisms of flaxseed (flour) on different substrate components. In particular, the altered balance between water absorption of flaxseed protein/gum polysaccharides and the interruption of gluten network, lipid lubrication, lipid-amylose complexes, syneresis, and so forth, were thoroughly elucidated. The overall impact of incorporating whole flaxseed (flour) on the quality and nutritional attributes of fortified food products, coupled with the possible solutions against negative influences are aimed. This paper could provide useful information for expanding the application of whole flaxseed (flour) based on the optimal edible and nutritional properties of fortified food products.


Assuntos
Ácidos Graxos Ômega-3 , Linho , Linho/química , Proteínas , Farinha/análise , Ácidos Graxos Ômega-3/química , Controle de Qualidade
4.
J Sci Food Agric ; 102(3): 949-956, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34302360

RESUMO

BACKGROUND: The waste of salted egg white resources has always been a serious problem in the food industry. In this current study, we report on a kind of Pickering emulsion system, which was stabilized by duck egg white nanogels (DEWNs) and sodium alginate (SA), followed by which this system was crosslinked by calcium carbonate (CaCO3 ) via controlling the gluconolactone (GDL) concentrations, aiming to open up a promising route for making full use of these protein resources. RESULTS: The droplet size of the emulsion exhibited a reduction with an increase in SA concentrations, indicating that higher negative charges and steric hindrance was useful for a stable emulsion system. Meanwhile, the result of rheology measurement showed that storage modulus (G') values were higher than loss modulus (G″) values of the samples at higher GDL concentration, revealing the formation of elastic gel-like networks in the system, which was fabricated by SA and Ca2+ released by the CaCO3 particles. The gel-like network structure in the continuous phase improved both the freeze-thaw and thermal stability of the obtained Pickering emulsion system. Encouragingly, the Pickering high internal phase emulsions (HIPEs, φ = 0.75) stabilized by DEWN/SA3 -GDL3 were prepared, which could be stored at 4 °C for at least 30 days without oiling-off and creaming. CONCLUSION: These findings not only develop a green ultra-stable Pickering emulsion system but also extend the potential commercial applications of duck egg white proteins in the food, cosmetics, and pharmaceutical industries. © 2021 Society of Chemical Industry.


Assuntos
Alginatos/química , Clara de Ovo/química , Nanogéis/química , Animais , Patos , Proteínas do Ovo/química , Emulsões/química , Reologia , Resíduos/análise
5.
J Agric Food Chem ; 69(39): 11709-11719, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34570506

RESUMO

Interfacial self-assembly has been a powerful driving force for fabricating functional and therapeutic carriers in emulsion systems. Herein, we reported a straightforward metal-phenolic supramolecular architecture, directly absorbed and cross-linked at the surfaces of oil drops and acted as the regulator between the oil and water interface to stabilize the emulsion systems. The results showed that the diverse interfacial properties and emulsion stability were tuned by the kinds and concentrations of polyphenols as well as the ratios of polyphenols to metal ions. Concretely, the TA-Fe3+ (coordinated by tannin acid and Fe3+)- or EGCG-Fe3+ (coordinated by EGCG and Fe3+)-based solid particles exhibited an increasing amount of interfacial adsorption with an increase in both polyphenol and metal ion concentrations or ratios of Fe3+ to polyphenols, and as a consequence of which, the prepared corresponding emulsions displayed enhanced emulsion stability and diverse interfacial characteristics. The rheological measurement results also exhibited that there was an increasing trend in both G' and G″, with enhanced concentrations or ratios of Fe3+ to polyphenols. Generally, our study not only highlighted a straightforward strategy for the directly interfacial fabrication of emulsions to improve their stability but also advanced the understanding of broadening the application scope of the metal-phenolic networks.


Assuntos
Fenóis , Água , Emulsões , Polifenóis , Reologia
6.
ACS Appl Bio Mater ; 4(3): 2686-2695, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35014307

RESUMO

There are multiple obstacles for the storage and digestion of orally administered bioactive macromolecules. This study developed a low-cost and sustained-release delivery system (sporopollenin exine capsules with zein/tannic acid modification) of proteins with excellent storage stability, and at the same time provided insights into the sustained-release mechanism through exploring the interaction between zein and tannic acid (TA). ß-Galactosidase (ß-Gal) was utilized as a model protein and loaded into sporopollenin exine capsules (SECs), which were then coated with the zein/TA system. Under the optimized zein/TA conditions, the zein/TA system showed better performance than the zein alone system in the sustained release of ß-Gal, with the residual activity of about 70.26% after 24 h of simulated digestion. Evaluation of the storage stability demonstrated a ß-Gal residual activity of nearly 90% for 28 days at 25 °C. Additionally, FTIR analysis demonstrated that the stability of the zein/TA system depends on both hydrogen bonding and certain covalent bonding through the Schiff-base reaction, and the sustained release is regulated by the bonding strength.


Assuntos
Materiais Biocompatíveis/metabolismo , Biopolímeros/metabolismo , Carotenoides/metabolismo , Taninos/metabolismo , Zeína/metabolismo , beta-Galactosidase/metabolismo , Materiais Biocompatíveis/química , Biopolímeros/química , Cápsulas/química , Cápsulas/metabolismo , Carotenoides/química , Escherichia coli/enzimologia , Ligação de Hidrogênio , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Teste de Materiais , Tamanho da Partícula , Taninos/química , Zeína/química , beta-Galactosidase/química
7.
Food Chem Toxicol ; 146: 111838, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33137424

RESUMO

Supplementing different quantities of boron can significantly affect immune function in rat spleen, but the mechanism of action behind this effect remains unclear. Our purpose was to study the involvement of the estrogen membrane receptor GPR30 in the effect of boron on the proliferation, apoptosis, and immune function of rat spleen lymphocytes. Results showed that the addition of 0.4 mmol/L boron had a beneficial effect on the immune function and proliferation of spleen lymphocytes, but the addition of 40 mmol/L boron had opposite effect. After using G-15 to selectively inhibit GPR30, the proportions of CD4+ and CD8+ T cells, the content of IL-2 and IFN-γ, and the expression of PCNA protein were significantly decreased, while lymphocyte apoptosis rate increased significantly (p < 0.05 or p < 0.01). After G-15 treatment, the addition of 0.4 mmol/L boron had no effects on T cell subsets, lymphocyte proliferation, PCNA protein expression, and IgG and cytokine content (P > 0.05), while the addition of 40 mmol/L boron did not change the effects on lymphocyte subsets, proliferation and apoptosis. The results suggested that GPR30 mediates the effects of 0.4 mmol/L boron boron on the proliferation, apoptosis and immune function of spleen lymphocytes.


Assuntos
Apoptose/efeitos dos fármacos , Boro/farmacologia , Proliferação de Células/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Baço/citologia , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade Celular , Linfócitos/fisiologia , Ratos , Receptores Acoplados a Proteínas G/genética
8.
J Agric Food Chem ; 68(47): 13990-14000, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33174430

RESUMO

There are multiple obstacles in the gastrointestinal tract (GIT) for oral administration of bioactive macromolecules. Here, we engineered an oral delivery vehicle (sporopollenin exine capsules with carboxymethylpachymaran (CMP)/metal ion modification) with targeted release based on food-grade ingredients and processing operations. Then, the interaction and binding mechanisms between CMP and metal ions in the vehicle were investigated. By using ß-galactosidase (ß-Gal) as a model protein, the systems were characterized for the surface morphology and monitored by the in vitro release profile of ß-Gal. Notably, the CMP/metal ion systems not only markedly decreased the CMP dosage but also achieved a valid long-term release compared with the previously reported CMP system. Among all the systems, the CMP/3% AlCl3 system showed the best ability to control the release with the maximum residual activity of ß-Gal at nearly 72% after 24 h of treatment. Subsequently, the interaction mechanism between CMP and metal ions within the system was characterized by the perspectives of microstructure, rheological properties, and spectroscopy characteristics. The results indicated that the low pH conditions are conducive to the further cross-linking of CMP and metal ions, resulting in a high gel strength and thus a dense structure, which can impact the controlled release of ß-Gal in the GIT. Overall, the system may be utilized in the administration of medical and functional foods, specifically for the delivery of bioactive proteins via the oral route.


Assuntos
Helianthus , Biopolímeros , Cápsulas , Carotenoides , Glucanos , Íons
9.
Food Res Int ; 127: 108691, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31882107

RESUMO

The properties of high loading capacity and long-term absorption are of great significance in the field of nutraceuticals or drugs delivery. Herein, we developed an innovative method to achieve these expected effects using plant exine capsules, a kind of natural pollen grains, which could provide large internal cavities for loading and robust exine against harsh conditions. In our work, we firstly made a soluble mixture of glycerol monostearate (GM) and nobiletin (NOB) inside the cavities of plant exine capsules by ultrasound with high temperature to obtain a supersaturated state of NOB, which could be characterized by XRD, DSC and FTIR. After that, the loaded capsules were cooled to room temperature. Alginate hydrogels were then selected for encapsulating and further controlling NOB release in simulated gastric and intestinal conditions. As a result, it demonstrated that our approach was able to reach an extremely high NOB loading capacity of 770 ±â€¯40 mg/g using sunflower pollen grains (SPGs). Meanwhile, the existence of GM, SPGs and alginate hydrogels all retarded the release of the NOB synergistically, thus taking a slow release effect in the stomach while a long-term effective absorption in the intestine. Taken together, our processing method of encapsulating hydrophobic nutraceuticals provides an important insight for broadening the applications of nutraceutical or drug encapsulation and delivery.


Assuntos
Alginatos/química , Antioxidantes/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Flavonas/administração & dosagem , Helianthus/química , Pólen/química , Cápsulas , Hidrogéis , Técnicas In Vitro
10.
Food Funct ; 10(8): 4782-4791, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31313784

RESUMO

ß-Galactosidase (ß-Gal) as a dietary supplement can alleviate symptoms of lactose intolerance. However, ß-Gal is deactivated due to the highly acidic conditions and proteases in the digestive tract. In this work, ß-Gal was encapsulated into L. clavatum sporopollenin exine capsules (SECs) to fabricate an oral-controlled release system and increase the stability of ß-Gal in the digestive tract. The SEC extraction process was optimized. A 3-hour vacuum loading was determined as the optimal loading time. Five different initial ratios of SECs : ß-Gal were optimized with the maximum enzyme retention rate reaching 79.40 ± 1.96%. Furthermore, ß-Gal-loaded SECs entrapped in carboxymethylpachymaran (CMP) could control the release of ß-Gal under simulated gastrointestinal conditions (SGC). The optimal enzyme retention rate reached 65.33 ± 1.46% within 24 h under SGC. Collectively, these results indicated that the entrapped SECs could be used as an effective oral delivery vehicle of ß-Gal to improve its performance as a dietary supplement in the digestion of lactose.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Glucanos/química , Lycopodium/química , Extratos Vegetais/química , beta-Galactosidase/química , Biopolímeros/química , Cápsulas/química , Cápsulas/metabolismo , Carotenoides/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/metabolismo , Composição de Medicamentos , Estabilidade Enzimática , Trato Gastrointestinal/metabolismo , Glucanos/metabolismo , Extratos Vegetais/metabolismo , Esporos/química , beta-Galactosidase/metabolismo
11.
Int J Biol Macromol ; 137: 69-76, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260766

RESUMO

ß-Galactosidase (ß-Gal) as dietary supplement has the ability to alleviate symptoms of lactose intolerance. This study investigated the ability of oligosaccharides to protect ß-Gal against heat stress. Four kinds of oligosaccharides including Isomalto-oligosaccharides (IMO), Xylo-oligosaccharides (XOS), Konjac-oligosaccharides (KOS), and Mycose significantly increased the activity retention of ß-Gal under heat treatment. The results of three assays including circular dichroism, fluorescence, and Fourier transform infrared spectroscopy (FTIR) illustrated that these oligosaccharides could stabilize the secondary and tertiary structure of ß-Gal under thermal conditions through hydrogen bond interaction. Unlike these four oligosaccharides, Chito-oligosaccharides (COS) changed the secondary and tertiary structure of ß-Gal, thus decreasing its activity retention rate. Under heat treatment, the activity retention rate of ß-Gal with optimal composition (30% IMO, w/v and 40% XOS, w/v) reached 82.1%, which was significantly higher than that of the native ß-Gal (the activity retention rate of 20%). This study provides an insight into the mechanism by which sugar stabilizes protein under heat stress and offers guidance for application of liquid lactase to food industry.


Assuntos
Temperatura Alta , Oligossacarídeos/farmacologia , beta-Galactosidase/química , beta-Galactosidase/metabolismo , Estabilidade Enzimática/efeitos dos fármacos , Resposta ao Choque Térmico/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Secundária de Proteína/efeitos dos fármacos , Estrutura Terciária de Proteína/efeitos dos fármacos
12.
Food Res Int ; 122: 273-282, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229081

RESUMO

Proteins and polysaccharides can be used to assemble colloidal delivery systems suitable for industrial applications, such as functional foods, supplements, pharmaceuticals, and personal care products. The purpose of this work was to compare the physicochemical and structural properties of colloidal delivery systems prepared from lysozyme and carboxymethyl cellulose (CMC) at different biopolymer ratios, pH values, and salt levels. Specifically, the performance of unheated ("complexes") and heated ("microgels") lysozyme-CMC systems were compared. Isothermal turbidity-pH titrations indicated that the critical pH value for complex formation was lower for microgels than for complexes. Complexes were prone to dissociation when the pH or ionic strength was altered due to weakening of electrostatic interactions between the CMC and lysozyme. Conversely, microgels remained intact when the pH or ionic strength was altered, exhibiting swelling or shrinkage rather than dissociation. These results have important implications for the selection of the most appropriate protein/polysaccharide systems to achieve specific functional requirements. Complexes may be more suitable for pH- or salt-based triggered release whereas microgels may be more suitable for sustained release.


Assuntos
Carboximetilcelulose Sódica/química , Microgéis/química , Muramidase/química , Fenômenos Químicos , Coloides/química , Eletricidade Estática
13.
Food Funct ; 10(6): 3344-3355, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31095149

RESUMO

The impact of phytic acid on lipid digestion and curcumin bioaccessibility in oil-in-water nanoemulsions was investigated using a simulated gastrointestinal tract (GIT). The size, charge, and structural organization of the colloidal particles in the system were measured as the curcumin-loaded emulsions (7 mg curcumin per g lipid) were passed through simulated mouth (pH 6.8, 2 min), stomach (pH 2.5, 2 hours), and small intestine (pH 7.0, 2 hours) stages. After the small intestine stage, the level of free fatty acids (FFAs) generated and the bioaccessibility of curcumin were measured. The total amount of FFAs released significantly decreased with increasing phytic acid level, from 105.7 ± 5.9% (control) to 78.4 ± 6.4% (0.5% phytic acid). Conversely, curcumin bioaccessibility significantly increased from 39.4 ± 3.5% (control) to 74.7 ± 2.6% (0.5% phytic acid). The inverse relationship between lipolysis and curcumin bioaccessibility was ascribed to the impact of phytic acid on droplet flocculation and the level of free calcium ions present, which affected the production of mixed micelles capable of solubilizing the nutraceutical. The knowledge obtained here might prove beneficial for the employment of phytic acid as a multifunctional ingredient that inhibits lipid digestion while boosting nutraceutical bioavailability.


Assuntos
Curcumina/metabolismo , Trato Gastrointestinal/metabolismo , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Ácido Fítico/química , Extratos Vegetais/metabolismo , Disponibilidade Biológica , Curcumina/química , Emulsões/química , Emulsões/metabolismo , Excipientes/química , Excipientes/metabolismo , Humanos , Modelos Biológicos , Tamanho da Partícula , Ácido Fítico/metabolismo , Extratos Vegetais/química
14.
Int J Nanomedicine ; 12: 3315-3330, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28490873

RESUMO

In this study, a novel coordination bonding system based on metal-tannic acid (TA) architecture on zein/carboxymethyl chitosan (CMCS) nanoparticles (NPs) was investigated for the pH-responsive drug delivery. CMCS has been reported to coat on zein NPs as delivery vehicles for drugs or nutrients in previous studies. The cleavage of either the "metal-TA" or "NH2-metal" coordination bonds resulted in significant release of guest molecules with high stimulus sensitivity, especially in mild acidic conditions. The prepared metal-TA-coated zein/CMCS NPs (zein/CMCS-TA/metal NPs) could maintain particle size in cell culture medium at 37°C, demonstrating good stability compared with zein/CMCS NPs. In vitro release behavior of doxorubicin hydrochloride (DOX)-loaded metal-TA film-coated zein/CMCS NPs (DOX-zein/CMCS-TA/metal NPs) showed fine pH responsiveness tailored by the ratio of zein to CMCS as well as the metal species and feeding concentrations. The blank zein/CMCS-TA/metal NPs (NPs-TA/metal) were of low cytotoxicity, while a high cytotoxic activity of DOX-zein/CMCS-TA/metal NPs (DOX-NPs-TA/metal) against HepG2 cells was demonstrated by in vitro cell assay. Confocal laser scanning microscopy (CLSM) and flow cytometry were combined to study the uptake efficiency of DOX-NPs or DOX-NPs-TA/metal. This system showed significant potential as a highly versatile and potent platform for drug delivery.


Assuntos
Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Quitosana/análogos & derivados , Quitosana/química , Doxorrubicina/química , Doxorrubicina/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Difusão Dinâmica da Luz , Células Hep G2/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Ligantes , Metais/química , Metais/metabolismo , Microscopia Confocal , Nanopartículas/administração & dosagem , Tamanho da Partícula , Taninos/química , Zeína/química
15.
Int J Biol Macromol ; 102: 218-224, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28392386

RESUMO

In this study, negatively charged phosvitin (PV) and positively charged chitosan (CS) were alternately deposited on negatively charged cellulose mats via layer-by-layer (LBL) self-assembly technique. Morphologies of the LBL films coating mats were observed by scanning electron microscope (SEM). Afterwards, in vitro biomimetic mineralization was carried out through incubation of the fibrous mats in a simulated body fluid (SBF) solution for different time. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were used to characterize the morphology and structure of the deposited mineral phase on the scaffolds. In addition, the cell culture experiment demonstrated that the scaffolds with the LBL structured films were of good cell compatibility for MC3T3-E1 cells. Moreover, the cell proliferation was affected by the number of deposition layers and the composition of outer-most layer. Confocal laser scanning microscopy (CLSM) and SEM imaging revealed a good performance of cell adhesion and spreading of MC3T3-E1 cells on the surface of biocomposite scaffold. So CS/PV nanofibrous mats were satisfactory for the composite to be used in bioapplications.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Quitosana/química , Eletricidade , Nanofibras/química , Fosfoproteínas/química , Células 3T3 , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Camundongos , Engenharia Tecidual , Alicerces Teciduais/química
16.
J Agric Food Chem ; 65(11): 2454-2460, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28241119

RESUMO

Edible gliadin nanoparticles (GNPs) were fabricated using the anti-solvent method. They possessed unique high foamability and foam stability. An increasing concentration of GNPs accelerated their initial adsorption speed from the bulk phase to the interface and raised the viscoelastic modulus of interfacial films. High foamability (174.2 ± 6.4%) was achieved at the very low concentration of GNPs (1 mg/mL), which was much better than that of ovalbumin and sodium caseinate. Three stages of adsorption kinetics at the air/water interface were characterized. First, they quickly diffused and adsorbed at the interface, resulting in a fast increase of the surface pressure. Then, nanoparticles started to fuse into a film, and finally, the smooth film became a firm and rigid layer to protect bubbles against coalescence and disproportionation. These results explained that GNPs had good foamability and high foam stability simultaneously. That provides GNPs as a potential candidate for new foaming agents applied in edible and biodegradable products.


Assuntos
Gliadina/química , Nanopartículas/química , Ar/análise , Caseínas/química , Cinética , Propriedades de Superfície , Água/análise
17.
Colloids Surf B Biointerfaces ; 146: 107-13, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27262260

RESUMO

In this study, bovine serum albumin (BSA) and chitosan (CS) were used to prepare BSA-CS nanogels by a simple green self-assembly technique. Then the nanogels were successfully used to entrap doxorubicin hydrochloride (DOX) with an entrapment ratio of 46.3%, aiming to realize the slow-release effect and lower the cytotoxicity of DOX. The IC50 values of DOX-loaded BSA-CS (DOX-BSA-CS) and free DOX obtained by MTT assay in SGC7901 cells were 0.22 and 0.05µg/mL, respectively. The cytotoxicity of DOX significantly decreased within 24h after encapsulation by the nanogels, indicating that the loaded drug could slowly release within 24h and the BSA-CS was a good slow release system. The cellular uptake experiments indicated DOX-BSA-CS diffused faster into the cancer cell than the bare drug. The flow cytometry and TUNEL assay proved DOX-BSA-CS could induce a larger apoptosis proportion of gastric cancer cells 7901 than the bare drug and it is promising to be used for curing gastric cancer.


Assuntos
Quitosana/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Polietilenoglicóis/química , Polietilenoimina/química , Soroalbumina Bovina/química , Neoplasias Gástricas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bovinos , Proliferação de Células/efeitos dos fármacos , Difusão , Humanos , Marcação In Situ das Extremidades Cortadas , Nanogéis , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas
18.
Ultrason Sonochem ; 31: 302-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26964953

RESUMO

Influence of high intensity ultrasound (HIUS) on the structure and properties of ovalbumin (OVA) were investigated. It was found that the subunits and secondary structure of OVA did not change significantly with HIUS treatment from the electrophoretic patterns and circular dichroism (CD) spectrum. The amount of free sulfhydryl groups increased and intrinsic fluorescence spectra analysis indicated changes in the tertiary structure and partial unfold of OVA after sonication increased. Compared with the untreated OVA, HIUS treatment increased the emulsifying activity and foaming ability, and decreased interface tension (oil-water and air-water interface), which due to the increased surface hydrophobicity and decreased the surface net charge in OVA, while the emulsifying and foaming stability had no remarkable differences. The increased particle size may be attributed to formation of protein aggregates. Moreover, the gelation temperatures of HIUS-treated samples were higher than the untreated OVA according to the temperature sweep model rheology, and this effect was consistent with the increased in surface hydrophobicity for ultrasound treated OVA. These changes in functional properties of OVA would promote its application in food industry.


Assuntos
Géis , Ovalbumina/química , Ultrassom , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Conformação Proteica , Reologia , Espectrometria de Fluorescência , Tensão Superficial
19.
Int J Biol Macromol ; 81: 477-82, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26299711

RESUMO

Sunlight photocatalyst was fabricated by in situ synthesis of Cu2O in the regenerated chitin (RC)/graphene oxide (GO) composite film, where the porous chitin film was used as the microreactor for the formation of nano Cu2O. Nano Cu2O was immobilized and evenly distributed in the matrix and Cu2O tended to grow on the GO sheets. Cu2O inside the matrix excite and generate free photoelectrons and electron holes, which was responsible for the degradation of dyes, while GO transferred the yielded photoelectrons to prevent the generation of local high potential zone and induce the chain degradation at more points. So it was found that the porous chitin film could load Cu2O and graphene at the same time, controlling the size of Cu2O and leading to easy recycle and reuse of the photocatalyst. Moreover, the introduction of GO has dramatically improved the photocatalytic activity of Cu2O in the Cu2O/GO/RC film, showing great potential application in wastewater treatment utilizing solar energy.


Assuntos
Quitina/química , Corantes/química , Grafite/química , Luz , Óxidos/química , Processos Fotoquímicos , Catálise , Cobre/química , Nanocompostos/química , Nanocompostos/ultraestrutura , Difração de Raios X
20.
Food Res Int ; 75: 98-105, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28454977

RESUMO

A facile approach was investigated to encapsulate and protect curcumin (Cur) by self-assembly of lysozyme (Ly) and carboxymethylcellulose (CMC) of different degrees of substitution (DSs). This work studied the influence of Ly-CMC coacervates on the binding, solubility and stability of Cur. The interactions of Cur with Ly-CMC coacervates were researched by UV-vis, steady-state fluorescence, synchronous fluorescence and circular dichroism spectra. These results were explained in terms of the formation of Ly-CMC coacervates with electrostatic interaction, which led to unfold the structure of Ly for providing Cur with more hydrophobic microenvironment than free Ly. Meanwhile, the CMC of higher DS provide more negative charges, and produce more attraction to Ly than that of lower DS values. Moreover, the coacervates of Ly-CMC of higher DS are found to be superior for enhancing the stability of Cur. Our work provided a new insight for understanding the biomolecule protective system based on protein/polysaccharide complexes.

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