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1.
Nat Commun ; 11(1): 958, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075974

RESUMO

The structural integrity of living plant cells heavily relies on the plant cell wall containing a nanofibrous cellulose skeleton. Hence, if synthetic plant cells consist of such a cell wall, they would allow for manipulation into more complex synthetic plant structures. Herein, we have overcome the fundamental difficulties associated with assembling lipid vesicles with cellulosic nanofibers (CNFs). We prepare plantosomes with an outer shell of CNF and pectin, and beneath this, a thin layer of lipids (oleic acid and phospholipids) that surrounds a water core. By exploiting the phase behavior of the lipids, regulated by pH and Mg2+ ions, we form vesicle-crowded interiors that change the outer dimension of the plantosomes, mimicking the expansion in real plant cells during, e.g., growth. The internal pressure enables growth of lipid tubules through the plantosome cell wall, which paves the way to the development of hierarchical plant structures and advanced synthetic plant cell mimics.


Assuntos
Células Artificiais/metabolismo , Materiais Biomiméticos/metabolismo , Parede Celular/metabolismo , Células Vegetais/metabolismo , Células Artificiais/citologia , Materiais Biomiméticos/química , Cápsulas/química , Cápsulas/metabolismo , Parede Celular/química , Parede Celular/ultraestrutura , Celulose/química , Microfluídica , Nanofibras/química , Ácido Oleico/química , Pectinas/química
2.
J Food Sci ; 85(2): 394-403, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31976556

RESUMO

The delivery of active probiotic cells in capsules can reduce probiotic cell loss induced by detrimental external factors during digestion. In this study, we determined the optimal conditions for the encapsulation of Weissella cibaria JW15 (JW15) within calcium and polyethylene glycol (PEG)-alginate with chicory root extract powder (CREP). JW15 was encapsulated as the core material (109 cells/mL, 2 mL/min), and a solution containing a mixture of 1.5% sodium alginate and 1% CREP was extruded into a receiving bath with 0.1 M calcium chloride (CaCl2 ) and 0.05% PEG. Capsule morphology and size were measured using optical microscopy. The optimal air pressure and frequency vibration for capsules containing alginate only (Al) were 200 mbar and 200 Hz, respectively and 100 mbar and 350 Hz for capsules containing alginate with CREP (Ch), respectively. The voltage for both capsules types was fixed at 1.35 kV. Then, the capsules were incubated in a simulated gastrointestinal (GI) system for 6 hr at 37 °C. The addition of PEG in a CaCl2 hardening solution led to degradation of the Ch capsule (Ch-PEG) and the release of cells into the small intestine vessel in the simulated GI system. By contrast, the cells were trapped within the Al capsules. Based on these data, effective encapsulation using alginate with CREP and PEG can enable JW15 to be released at a targeted anatomical site of activity within the GI system, thereby, enhancing the efficacy of probiotic cells. These protective effects can be leveraged during the development of probiotic products. PRACTICAL APPLICATION: Weissella cibaria JW15 (109 cells/mL) was encapsulated in biodegradable and biocompatible capsules, prepared by mixing 1.5% alginate with 1% chicory root extract powder (CREP) in 0.1 M CaCl2 and 0.05% PEG using an encapsulator. The optimal processing parameters were as follows: pressure, 100 mbar; vibration frequency, 350 Hz; voltage, 1.35 kV; and core flow rate, 2 mL/min. When the resulting capsules were subjected to a simulated gastrointestinal system for 6 hr, the cells were released into the small intestine, and up to 95% cell viability was preserved. These results suggest that capsules made from alginate with CREP and formulated using calcium and PEG are a promising delivery system for probiotic cells.


Assuntos
Alginatos/química , Chicória/química , Composição de Medicamentos/métodos , Extratos Vegetais/química , Probióticos/química , Weissella/química , Cápsulas/química , Cápsulas/metabolismo , Trato Gastrointestinal/metabolismo , Humanos , Viabilidade Microbiana , Modelos Biológicos , Raízes de Plantas/química , Probióticos/metabolismo
3.
Food Chem ; 313: 126129, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31935665

RESUMO

Thymoquinone is a chief phytochemical constituent of black cumin seed oil (BCSO) and shows strong bioactivity. It has a weak stability against environmental conditions like heat and light. Encapsulation process by Saccharomyces cerevisiae is a popular technique to preserve the bioactivity and increase the stability of functional bioactive compounds. In the current study, BCSO was encapsulated by both plasmolysed (PYC) and nonplasmolysed yeast cell (NPYC) and stability of thymoquinone and bioactive properties of all samples were evaluated. And also, some physicochemical, morphological and conformational characterizations were carried out for the encapsules. The results showed that thymoquinone concentration and its bioactivity were preserved better in PYC during storage compared to BCSO and NPYC. The highest degradation ratio of thymoquinone during storage for the BCSO was 96.78% while the lowest one was for the PYC sample (52.63%).


Assuntos
Benzoquinonas/química , Cápsulas/química , Nigella sativa/metabolismo , Óleos Vegetais/química , Saccharomyces cerevisiae/química , Benzoquinonas/metabolismo , Depuradores de Radicais Livres/química , Nigella sativa/química , Sementes/química , Sementes/metabolismo
4.
Food Chem ; 313: 126115, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31927206

RESUMO

The effect of different polysaccharides combinations on the stability of maqui extract was studied in order to design functional foods, dietary supplements or natural colorants. Encapsulation by freeze-drying using maltodextrin, gum Arabic and inulin at 10, 20 and 30% was performed and phenolics, anthocyanin, antioxidant capacity and color difference of the microcapsules were determined. The stability of the bioactives after 60 days storage at 25 °C was also evaluated, along with analysis of aw, adsorption isotherm, and microstructure to characterize the powders. 10% encapsulating polysaccharide produced best results, with maltodextrin leading to highest process efficiency, while the mixture of maltodextrin/inulin in equal proportion led to highest retention of polyphenols (91.1%) and anthocyanin (98.8%) during storage. The inulin microcapsules retained 94.1% of its antioxidant capacity compared to 25.3% for the freeze-dried maqui powder. Concentration level and polysaccharide matrix of encapsulating agent significantly affect retention of bioactives in the microcapsules.


Assuntos
Antocianinas/análise , Antioxidantes/química , Cápsulas/química , Elaeocarpaceae/química , Fenóis/análise , Extratos Vegetais/química , Elaeocarpaceae/metabolismo , Armazenamento de Alimentos , Liofilização , Frutas/química , Frutas/metabolismo , Goma Arábica/química , Polissacarídeos/química , Temperatura
5.
Mater Sci Eng C Mater Biol Appl ; 106: 110251, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753346

RESUMO

In this work, a versatile folic acid (FA) decorated reductive-responsive ε-poly-l-Lysine (ε-PL)-based microcapsules (FA-ε-PLMCs) were designed and facilely assembled by using sonochemical technique. Cellular uptake experiment of FA-ε-PLMCs loaded with Coumarin 6 (C6) as a model of hydrophobic drugs implied that hydrophobic drugs encapsulated inside FA-ε-PLMCs could be delivered selectively into Hela cells via folate-receptor (FR)-mediated endocytosis due to FA decorated on microcapsules. Furthermore, the shells of FA-ε-PLMCs cross-linked by disulfide bonds were derived from sulfhydryl groups (-SH) under ultrasonication. Under reductive environment, the hydrophobic drugs loaded in FA-ε-PLMCs would be easily released due to the cleavage of disulfide bonds. Benefiting from their suitable particle size, good loading capacity for hydrophobic drugs, remarkable targetability and reductive-triggered release, the obtained FA-ε-PLMCs could be a promising hydrophobic drugs carrier for the cancer treatment.


Assuntos
Cápsulas/química , Portadores de Fármacos/química , Ácido Fólico/química , Polilisina/química , Sistemas de Liberação de Medicamentos/métodos , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Food Chem ; 302: 125347, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31430631

RESUMO

This work aims to prolong the storage stability of polyphenols, obtained from grape pomace, using a spray drying-based microencapsulation technique. The microcapsules obtained under optimal conditions were stored at two different relative humidities (33% and 52%) during 75 days. The analyses of total phenolic content, antioxidant activity, and individual phenolic compounds were carried out every 15 days, and the most stable microcapsules were achieved with maltodextrin DE4-7 prepared by adding gum Arabic to the wall material at a ratio of 8:2. The phenolic content loss rate was found to be in a range of 0.93-5.42 % depending on phenolic compound. The decrease in the content of rutin, chlorogenic acid, epicatechin, caffeic acid, gallic acid, caftaric acid and catechin was only 0.93, 2.09, 2.13, 2.27, 2.41, 3.40 and 5.42%, respectively. These results indicate more efficient storage conditions than those of previously reported studies.


Assuntos
Cápsulas/química , Armazenamento de Alimentos , Polifenóis/química , Vitis/química , Antioxidantes/análise , Antioxidantes/química , Catequina/análise , Catequina/química , Ácido Clorogênico/análise , Ácido Clorogênico/química , Composição de Medicamentos/métodos , Goma Arábica/química , Umidade , Fenóis/análise , Fenóis/química , Extratos Vegetais/química , Polifenóis/análise , Polissacarídeos/química , Rutina/análise , Rutina/química
7.
Food Chem ; 304: 125427, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31494501

RESUMO

Solution-enhanced dispersion by supercritical carbon dioxide (SEDS) and spray drying (SD) were used to microencapsulate red palm oil (RPO) to prolong the functionality of carotenes and vitamin E. The protective effects provided by SEDS and SD were evaluated in terms of the oxidative stability (65 °C for 35 days), fatty acid compositions, color change and degradation kinetics of carotenes and vitamin E (25 °C, 45 °C, 65 °C, and 85 °C for up to 198 days). SEDS microcapsules (SEDS-M) were the most oxidatively stable (total oxidation (Totox): 26.5), followed by SD microcapsules (SD-M) (34.9) and RPO (56.7). Degradation of carotenes and vitamin E fitted well a first-order kinetic model (average absolute relative deviation = 2-16%). SEDS-M offered better protection to vitamin E (Ea = 36 kJ/mol), whereas SD-M provided better protection for α +â€¯ß carotene (Ea = 29 kJ/mol). Overall, encapsulation protected RPO during storage, with SEDS-microencapsulated RPO performing better than SD-microencapsulated RPO.


Assuntos
Cápsulas/química , Armazenamento de Alimentos , Óleo de Palmeira/química , Dióxido de Carbono , Carotenoides , Cinética , Oxirredução , Óleo de Palmeira/análise , Vitamina E , beta Caroteno
8.
Food Chem ; 307: 125523, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639572

RESUMO

Lutein is a bioactive found in dark leafy vegetables that may be used as a nutraceutical agent in foodstuff and an inhibitor of key enzymes of the human body such as those involved in the cholinergic system. However, its high hydrophobicity leads to low bioavailability and must be overcome if lutein is to be added in foods. The objective of this study was to evaluate the influence of nanoencapsulated lutein in the activity of the acetylcholinesterase enzyme. The in vitro study was carried out using water in order to evaluate the impact of encapsulation on the hydrophilicity of lutein. In vitro assays showed that lutein, both free and nanoencapsulated, presented a mixed-type inhibition behavior, and encapsulated lutein was able to inhibit acetylcholinesterase activity even in an aqueous medium. Inhibition was also showed by the in silico docking results which show that lutein interacted with the pocket region of the enzyme.


Assuntos
Acetilcolinesterase/metabolismo , Cápsulas/química , Luteína/química , Simulação de Acoplamento Molecular , Nanopartículas/química , Acetilcolinesterase/química , Sítios de Ligação , Suplementos Nutricionais/análise , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Luteína/metabolismo , Estrutura Terciária de Proteína
9.
Nat Commun ; 10(1): 5687, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831732

RESUMO

Cavity creation is a key to the origin of biological functions. Small cavities such as enzyme pockets are created simply through liner peptide folding. Nature can create much larger cavities by threading and entangling large peptide rings, as learned from gigantic virus capsids, where not only chemical structures but the topology of threaded rings must be controlled. Although interlocked molecules are a topic of current interest, they have for decades been explored merely as elements of molecular machines, or as a synthetic challenge. No research has specifically targeted them for, and succesfully achieved, cavity creation. Here we report the emergence of a huge capsular framework via multiple threading of metal-peptide rings. Six equivalent C4-propeller-shaped rings, each consisting of four oligopeptides and Ag+, are threaded by each other a total of twelve times (crossing number: 24) to assemble into a well-defined 4 nm-sized sphere, which acts as a huge molecular capsule.


Assuntos
Cápsulas/química , Metais , Peptídeos/química , Antracenos/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Conformação Proteica , Piridinas , Prata/química
10.
Int J Mol Sci ; 20(19)2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31590233

RESUMO

A hollow-type spherical bacterial cellulose (HSBC) gel prepared using conventional methods cannot load particles larger than the pore size of the cellulose nanofiber network of bacterial cellulose (BC) gelatinous membranes. In this study, we prepared a HSBC gel encapsulating target substances larger than the pore size of the BC gelatinous membranes using two encapsulating methods. The first method involved producing the BC gelatinous membrane on the surface of the core that was a spherical alginate gel with a diameter of 2 to 3 mm containing the target substances. With this method, the BC gelatinous membrane was biosynthesized using Gluconacetobacter xylinus at the interface between the cell suspension attached onto the alginate gel and the silicone oil. The second method involved producing the BC gel membrane on the interface between the silicone oil and cell suspension, as well as the spherical alginate gel with a diameter of about 1 mm containing target substances. After the BC gelatinous membrane was biosynthesized, an alginate gel was dissolved in a phosphate buffer to prepare an HSBC gel with the target substances. These encapsulated substances could neither pass through the BC gelatinous membrane of the HSBC gel nor leak from the interior space of the HSBC gel. These results suggest that the HSBC gel had a molecular sieving function. The HSBC gel walls prepared using these methods were observed to be uniform and would be useful for encapsulating bioactive molecules, such as immobilized enzymes in HSBC gel, which is expected to be used as a drug carrier.


Assuntos
Cápsulas/química , Celulose/análogos & derivados , Gluconacetobacter xylinus/química , /química , Alginatos/química , Membranas Artificiais , Silicones/química
11.
Int J Pharm ; 570: 118661, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491482

RESUMO

There have been many strategies to increase solubility, dissolution rates, and oral bioavailability of fenofibrate such as micronization, nanonization, solid dispersion, and emulsion so far. To our knowledge, only first three technologies have been applied in producing marketed products, and no combination of solid dispersion and pellet has been found even in laboratory-based reports. Therefore, the aim of this study was to develop novel solid dispersion-based pellets via an one-step process directly from fenofibrate powder using layering method. Developed fenofibrate pellets were in vitro characterized on size distribution, dissolution rates, sensory evaluation and stability. In addition, the transformation from crystalline fenofibrate to amorphous fenofibrate, and intermolecular interactions of fenofibrate in solid dispersion were confirmed using physico-chemical methods. The dissolution rate of pellets containing fenofibrate was significantly higher than that of the reference, Lipanthyl® 160 mg tablets at early stage, satisfying the criteria in USP 38. The pellets, then, were packed in hard capsules for bioequivalence studies in experimental beagle dogs using a validated HPLC assay. Final findings of the present study should be beneficial for further development of new fenofibrate formulations containing solid dispersion-based pellets which were bioequivalent to Lipanthyl® 160 mg tablets.


Assuntos
Implantes de Medicamento/química , Fenofibrato/química , Administração Oral , Animais , Disponibilidade Biológica , Cápsulas/química , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cães , Emulsões/química , Hipolipemiantes/química , Masculino , Tamanho da Partícula , Solubilidade/efeitos dos fármacos , Comprimidos/química , Equivalência Terapêutica
12.
Mater Sci Eng C Mater Biol Appl ; 104: 109867, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499952

RESUMO

The objective of this study was to prepare European eel oil (EO) microcapsules using European eel protein isolate (EPI) as a wall material and investigate its oxidative stability. The EPI emulsions were obtained at different EO: EPI ratios (1:1, 1:2 and 1:4, w/w) and using two emulsification procedures: Homogenization (H) and homogenization followed by ultrasonication (HU) treatments. The microcapsules prepared by combining the two emulsification processes (HU) and at core and wall ratio of was 1:4 presented the smallest particles size and the greatest encapsulation efficiency (68.50%) and oxidative stability. Scanning electron microscopy (SEM) images proved the spherical shape of all microcapsules without fissure on the surface. The capsules exhibited an interesting antioxidant activity depending on the EO:EPI ratio, especially for the metal chelating potential. Thus, the effect of ultrasonication process and the EPI concentration on the characteristic, the stability and the antioxidant activity of the encapsulated EO has been proved.


Assuntos
Anguilla/fisiologia , Antioxidantes/farmacologia , Cápsulas/química , Dessecação , Emulsões/química , Óleos de Peixe/química , Proteínas de Peixes/isolamento & purificação , Animais , Compostos de Bifenilo/química , Ácidos Graxos/análise , Depuradores de Radicais Livres/química , Umidade , Oxirredução , Picratos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria , Água
13.
ACS Appl Mater Interfaces ; 11(40): 37313-37321, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31517474

RESUMO

A simple process is developed for the one-step preparation of dual-compartment alginate microcapsules with controlled size and structure from microfluid-generated water-in-water-in-oil (W/W/O) emulsion droplet. Unlike other methods that rely on transient W/W/O emulsion droplet, we introduce an aqueous two-phase system (ATPS) to form a stable W/W/O emulsion droplet as a template for preparing dual-compartment alginate microcapsules. Two different bioactive molecules are able to be spatially confined encapsulated in the shell and core of alginate microcapsules due to the partitioning effect of ATPS and the high viscosity of alginate solution. Moreover, an enzyme cascade reaction with a spatial confined glucose oxidase and horseradish peroxidase in the shell and core of alginate microcapsules confirms its excellent biocompatibility and high activity. This method provides a green platform for enzyme-catalyzed tandem reactions and controlled sequential release of multiple drugs based on alginate microcapsules.


Assuntos
Alginatos/química , Cápsulas/química , Emulsões/química , Microfluídica , Óleos/química , Água/química , Biocatálise , Fluoresceína-5-Isotiocianato/análogos & derivados , Glucose Oxidase/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Microfluídica/instrumentação , Tamanho da Partícula , Soroalbumina Bovina
14.
Eur J Pharm Biopharm ; 144: 174-179, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31541663

RESUMO

Capsules are a widely used oral dosage form due to their simplicity and ease of manufacture. They are equally popular for both pharmaceutical and nutraceutical products and since they do not need extensive formulation development, it is a dosage form of choice for new drugs undergoing animal or clinical trials. In addition to the standard hard-gelatin or cellulose-based vegetarian capsules, functional capsules such as those with built-in gastroresistance would be of great value. In this work, commonly used enteric polymers were investigated for the production of hard-capsules. The polymers used in this study included cellulose derivatives (HPMC AS-LF and HP-55) and acrylic/methacrylic acid derivatives (EUDRAGIT L100 and S100). A range of concentrations of polymers and plasticisers were tested to optimise the formulation for the production of capsule shells with desirable physicochemical and gastroresistance characteristics. Drug release from optimised capsules produced from HPMC AS-LF, HP-55, EUDRAGIT L100 and S100 was shown to be comparable to drug release from corresponding polymer-coated tablets in both compendial and physiological bicarbonate buffer. In summary, herein we report a simple method for producing enteric capsule shells which do not need an additional coating step which, if validated at large scale, can significantly reduce the cost of manufacturing of conventional enteric coated dosage forms. These capsules are also likely to improve the inter-tablet variability in post-gastric drug release inherent in conventional dosage forms due to coating variability.


Assuntos
Cápsulas/química , Polímeros/química , Bicarbonatos/química , Tampões (Química) , Celulose/química , Química Farmacêutica/métodos , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Excipientes/química , Gelatina/química , Concentração de Íons de Hidrogênio , Metacrilatos/química , Metilcelulose/análogos & derivados , Metilcelulose/química , Ácidos Polimetacrílicos/química , Solubilidade/efeitos dos fármacos , Comprimidos/química
15.
J Food Sci ; 84(10): 2745-2757, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31546290

RESUMO

Saffron petal, as a byproduct of saffron processing, contains a considerable amount of antioxidant compounds. In the present study, the effect of drying methods (spray and freeze) and different wall structures (maltodextrin and pectin) was investigated on the physicochemical characteristics of microcapsules of saffron petal extracts. Results showed that the increase of the pectin ratio in wall composition leads to the increase of polyphenols content and antioxidant activity of microcapsules. Microencapsulation efficiency and loading capacity in pectin-contained samples were higher than pure maltodextrin samples. Moreover, microcapsules obtained from spray drying method had higher microencapsulation efficiency and loading capacity in comparison with microcapsules obtained from freeze drying method. Also, scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry have been shown to be useful tools for establishing the difference between produced microcapsules. High-performance liquid chromatography was used to evaluate the polyphenolic compounds of the microsphere. The chromatograms obtained from both encapsulation methods indicated high levels of routine in microcapsules of saffron petal extract. In addition, the release of polyphenols from microcapsules of saffron petal extract was evaluated under simulated gastrointestinal conditions. The results indicated that the release behavior of the microcapsules varied according to the type of drying method and wall composition. To assess the shelf life, the microcapsules were kept at different temperatures and relative humidities for 16 weeks. The microcapsules produced by freeze drying and containing high levels of pectin in wall composition had the highest antioxidant activity when kept in relative humidity of 11% and temperature of 4 °C. PRACTICAL APPLICATION: Saffron petal is the huge amount of saffron by-product and contains a number of various antioxidant compounds. Microencapsulation of its valuable compounds results in preventing the destruction of these compounds by environmental factors and their increased bioavailability. Indeed, this paper focuses on the release of microencapsulated powder in the simulated system of the digestive system that helps us to improve the shelf life of the final product during the process and controlled release of compounds in the food and pharmaceutical industries.


Assuntos
Crocus/química , Composição de Medicamentos/métodos , Trato Gastrointestinal/metabolismo , Fenóis/química , Cápsulas/química , Cápsulas/metabolismo , Cromatografia Líquida de Alta Pressão , Digestão , Flores/química , Humanos , Modelos Biológicos , Fenóis/isolamento & purificação , Fenóis/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Polifenóis/análise , Polissacarídeos/química
16.
Carbohydr Polym ; 223: 115065, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426953

RESUMO

Probiotics are believed to provide benefits to human health; however, a good storage stability is the prerequisite for the probiotic products making function. Herein, we reported a pathway to fabricate the Ca-alginate/cryoprotectants/cellulose composite (ACFP) capsules to protect L. plantarum cells, which showed the minimal loss of viability during the vacuum freeze-drying process. The trehalose and whey protein isolate (WPI) ingredients in the cryoprotectants prolonged the dissolution time of Ca-alginate shell, which contributed to controlling the release of cells in the desired region. The dry ACFP capsules exhibited gradual release of L. plantarum cells in simulated intestinal fluid (SIF), 2.6 × 106 cfu/mL at 210 min. In addition, 0.1 g of the dry ACFP capsules showed the viable release amount of 3.3 × 106 cfu/mL after the storage of 160 days at 4 °C. The promising results provided a strategy of encapsulating probiotic cells to achieve long-term storage stability and enhanced controlled release behavior in simulated intestinal fluid in the meantime.


Assuntos
Alginatos/química , Celulose/química , Lactobacillus plantarum , Probióticos , Cápsulas/química , Crioprotetores/química , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Glicerol/química , Viabilidade Microbiana/efeitos dos fármacos , Trealose/química , Proteínas do Soro do Leite/química
17.
Carbohydr Polym ; 223: 115118, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426975

RESUMO

New biocompatible amphiphilic block copolymers were prepared using two natural compounds as starting materials, a polysaccharide (dextran) and a bile acid (deoxycholic acid). The copolymers were synthesized by dipolar 1,3-cycloaddition reaction between dextran with azide end groups and deoxycholic acid - oligo(ethylene glycol)s polyester with propargyl end groups. Different copolymer composition were obtained by variation of molecular weights of dextran (Mn 4.5, 8, 15 kDa) and polyester (Mn 2-6 kDa), as well as the length of oligo(ethylene glycol) (2-4 ethylenglycol units) used for polyester synthesis. These copolymers can for micelle like aggregates in aqueous medium with nanometric size (50-600 nm) and spherical form, as assessed by light scattering, atomic force microscopy and transmission electron microscopy. Encapsulation of the hydrophobic drug curcumin in micelles could increase 68,181 times its water solubility, and curcumin release from micelles was slow and with reduced burst effect.


Assuntos
Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Curcumina/química , Ácido Desoxicólico/química , Dextranos/química , Polímeros/síntese química , Tensoativos/síntese química , Materiais Biocompatíveis/química , Cápsulas/química , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Micelas , Conformação Molecular , Tamanho da Partícula , Polímeros/química , Solubilidade , Propriedades de Superfície , Tensoativos/química
18.
Carbohydr Polym ; 223: 115128, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31427012

RESUMO

Nanoparticle delivery systems have been widely investigated as new vaccines strategy to enhance the immune responses to antigens against infectious diseases. The positively charged nanoparticles could efficiently improve the immune responses due to targeting and activating the antigen-presenting cells. In this study, the immunopotentiator Angelica sinensis polysaccharide (ASP) was encapsulated into Poly (lactic-co-glycolic acid) (PLGA) nanoparticles, and the polyethylenimine, one of the cationic polymers, was used to coat nanoparticles to develop a new nanoparticle delivery system (ASP-PLGA-PEI) with positively charged. The ASP-PLGA-PEI nanoparticles significantly activated macrophages, and promoted the expression of the MHCII and CD86 and the production of IL-1ß and IL-12p70 cytokines of macrophages. Furthermore, the antigen adsorbed on the surface of the ASP-PLGA-PEI nanoparticles enhanced the antigen uptake by macrophages. Moreover, the mice immunized with PCV2 antigen adsorbed ASP-PLGA-PEI nanoparticles significantly enhanced PCV2-specific IgG immune response and the levels of cytokines, induced a mixed Th1/Th2 immune response with Th1 bias compared with other groups. These findings demonstrate that the positively charged nanoparticles (ASP-PLGA-PEI) have the potential to serve as an effective vaccine delivery and adjuvant system to induce vigorous and long-term immune responses.


Assuntos
Angelica sinensis/química , Imunoglobulina G/química , Nanopartículas/química , Polietilenoimina/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Polissacarídeos/química , Adjuvantes Imunológicos , Adsorção , Angelica sinensis/imunologia , Reações Antígeno-Anticorpo , Antígenos/química , Antígenos/imunologia , Cápsulas/química , Imunoglobulina G/imunologia , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/imunologia , Polissacarídeos/imunologia , Propriedades de Superfície , Vacinação
19.
Sensors (Basel) ; 19(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408931

RESUMO

Conceptual and commercial examples of implantable sensors have been limited to a relatively small number of target analytes, with a strong focus on glucose monitoring. Recently, surface-enhanced Raman spectroscopy (SERS) pH sensors were demonstrated to track acid-producing enzymatic reactions targeting specific analytes. We show here that SERS pH tracking in the basic regime is also possible, and can be used to monitor urea concentration. To accomplish this, we developed a hydrogel consisting of polyelectrolyte multilayer microcapsules containing a SERS-sensitive pH reporter (4-mercapopyridine capped silver nanoparticles modified with bovine serum albumin). This pH sensing material exhibited a sensitive Raman scattering response to a wide range of pH from 6.5-9.7. By incorporating urease into the hydrogel matrix, the new sensor was capable of distinguishing urea concentrations of 0, 0.1, 1, and 10 mM. We also found that bovine serum albumin (BSA) prevented severe aggregation of the nanoparticle-based pH sensor, which improved sensing range and sensitivity. Furthermore, BSA safeguarded the pH sensor during the encapsulation procedure. Together, the combination of materials represents a novel approach to enabling optical sensing of reactions that generate pH changes in the basic range.


Assuntos
Hidrogéis/química , Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/métodos , Ureia/análise , Animais , Cápsulas/química , Bovinos , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Polieletrólitos/química , Coroa de Proteína/química , Soroalbumina Bovina/química
20.
J Microencapsul ; 36(5): 421-431, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31401914

RESUMO

This work describes viability and distribution of INS-1E beta cells in shell-crosslinked alginate capsules, focussing on cells located near the capsule surface. Capsules were formed by air-shearing alginate suspensions of INS-1E cells into a gelling bath, and coating with poly-l-lysine (PLL) and 50% hydrolysed poly(methylvinylether-alt-maleic anhydride) to form crosslinked networks reinforcing the capsule surfaces. The percentage of cells at the capsule surface were determined using 2D and 3D confocal colocalization mapping. Encapsulated INS-1E cells showed high cell viability and progressive cell clustering out to six weeks. About 30% of cells were initially colocated with the 20 micrometer thick alginate-PLL-PMM50 shell, with 7% of cells protruded at the capsule surfaces, both reflecting random cell distributions. Protruding cells may cause cell-based immune responses, weaken capsules, and potentially result in cell escape from the capsules. The data shown indicate that reinforcing capsules with crosslinked shells may assist in preventing cell exposure and escape.


Assuntos
Alginatos/química , Células Imobilizadas/citologia , Reagentes para Ligações Cruzadas/química , Células Secretoras de Insulina/citologia , Polilisina/análogos & derivados , Animais , Cápsulas/química , Linhagem Celular , Extensões da Superfície Celular/ultraestrutura , Sobrevivência Celular , Células Imobilizadas/ultraestrutura , Géis/química , Células Secretoras de Insulina/ultraestrutura , Anidridos Maleicos/química , Polilisina/química , Ratos
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