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1.
Int J Nanomedicine ; 15: 4847-4858, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764922

RESUMO

Background: Bisphosphonates have very low bioavailability and cause irritation of the esophagus and stomach. This study was planned to improve the oral bioavailability of ibandronate through the formation of a raft in the stomach. Bisphosphonate-induced irritation of the esophagus and stomach is prevented by the formation of a raft. Materials and Methods: The nanostructured raft was developed through the use of nanosized citrus pectin (NCP). The particle size of NCP was measured by zeta sizer and SEM. The percentage of NCP and the neutralization profile of raft was studied. The ibandronate, polymers, and the developed formulation were characterized by FTIR, XRD, TGA, and DSC. The release of ibandronate was studied in 0.1 N HCl, 0.5 N HCl, 1 N HCl, and simulated gastric fluid (SGF) and a cell viability study was performed using Caco-2 cells. The PPR5 formulation and Bonish 150 mg tablets were selected as test and reference formulations, respectively, for pharmacokinetic study. Twelve healthy albino rats were taken and divided into two groups using a Latin square crossover design, and the blood samples were collected for 24 hours. Results: The SEM image showed that the particle size of NCP was 159 nm. The raft of PPR5 showed 94% NCP and 45 minutes duration of neutralization. The FTIR and XRD showed chemical stability and a uniform distribution of ibandronate in the raft. The TGA and DSC indicated the thermal stability of formulation. The release of 99.87% ibandronate at 20 minutes was observed in the SGF. The values of C max for the reference and test formulations were 493±0.237 ng/mL and 653±0.097 ng/mL, respectively. The AUC(0-t) of the reference and test formulations was 3708.25±3.418 ng/mL.h and 6899.25±3.467 ng/mL.h, respectively. Conclusion: The NCP has been successfully prepared from citrus pectin and has shown effective porous raft formation. The bioavailability of the ibandronate from newly developed PPR5 was higher than the already marketed formulation.


Assuntos
Portadores de Fármacos/química , Mucosa Gástrica/metabolismo , Ácido Ibandrônico/farmacologia , Ácido Ibandrônico/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Células CACO-2 , Humanos , Ácido Ibandrônico/administração & dosagem , Masculino , Pectinas/química , Ratos
2.
Food Chem ; 332: 127383, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615383

RESUMO

This study represents a rapid and non-destructive approach based on mid-infrared (MIR) spectroscopy, time domain nuclear magnetic resonance (TD-NMR), and machine learning classification models (ML) for monitoring soluble pectin content (SPC) changes in orange juice. Current reference methods of SPC in orange juice are laborious, requiring several extractions with successive adjustments hindering rapid process intervention. 109 fresh orange juices samples, representing different harvests, were analysed using MIR, TD-NMR and reference method. Unsupervised algorithms were applied for natural clustering of MIR and TD-NMR data in two groups. Analyses of variance of the two MIR and TD-NMR datasets show that only the MIR groups were different at 95% confidence for SPC average values. This approach allows build classification models based on MIR data achieving 85% and 89% of accuracy. Results demonstrate that MIR/ML can be a suitable strategy for the quick assessment of SPC trends in orange juices.


Assuntos
Citrus sinensis/química , Sucos de Frutas e Vegetais/análise , Aprendizado de Máquina , Pectinas/química , Citrus sinensis/metabolismo , Análise por Conglomerados , Humanos , Espectroscopia de Ressonância Magnética , Pectinas/metabolismo , Análise de Componente Principal , Espectrofotometria Infravermelho
3.
Food Chem ; 332: 127366, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32619940

RESUMO

High methyl-esterified citrus pectin (HMCP) molecules could be self-assembled into micelles in water. The morphology of HMCP micelles in water was irregular spheres, long rods, and arc-shaped. Most of HMCP molecules cross-linked with HMCP micelles in the presence of calcium chloride and increased the range of size distribution of HMCP micelles. A little number of HMCP molecules cross-linked with each other to form 80 nn ~ 200 nm microgel particles. Calcium chloride could improve HMCP emulsification when its concentration was more than 70 mmol/L. HMCP micelles could be adsorbed on the surface of emulsion droplets. The emulsion prepared with HMCP and calcium chloride was similar to the Pickering emulsion.


Assuntos
Cloreto de Cálcio/química , Pectinas/química , Emulsões , Esterificação , Metilação , Micelas , Água/química
4.
Food Chem ; 331: 127320, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32562981

RESUMO

The co-existence of polysaccharides and enzymes in the food matrix could form complexes that directly influence the catalytic efficacy of enzymes. This work investigated the self-assembly behaviors of α-amylase and charged polysaccharides and fabricated the α-amylase/polysaccharides complex coacervates. The results showed that the linear charge density of polysaccharides had a critical impact on the complex formation, structure, and enzyme protection under acidic conditions. At low pH, α-amylase formed compact and tight coacervates with the λ-carrageenan. However, α-amylase/pectin coacervates dissociated when the pH was lower than 3.0. The optimized binding ratio of α-amylase/λ-carrageenan was 12:1, and α-amylase/pectin was 4:1. Finally, the α-amylase/λ-carrageenan complex coacervates effectively immobilized the enzyme and almost 70% of enzyme activity remained in coacervates after exposure to pH3.0 for 1 h. This study demonstrates that the change in the linear charge density of polysaccharides could regulate the enzyme-catalyzed process in food processing by a simple and fine-controlled method.


Assuntos
Enzimas Imobilizadas/química , Polissacarídeos/química , alfa-Amilases/química , Carragenina/química , Concentração de Íons de Hidrogênio , Pectinas/química
5.
PLoS One ; 15(6): e0235090, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569270

RESUMO

Tumor is a prevalent great threat to public health worldwide and multidrug resistance (MDR) of tumor is a leading cause of chemotherapy failure. Nanomedicine has shown prospects in overcoming the problem. Doxorubicin (DOX), a broad-spectrum anticancer drug, showed limited efficacy due to MDR. Herein, a doxorubicin containing pectin nanocell (DOX-PEC-NC) of core-shell structure, a pectin nanoparticle encapsulated with liposome-like membrane was developed. The DOX-PEC-NC, spheroid in shape and sized around 150 nm, exerted better sustained release behavior than doxorubicin loading pectin nanoparticle (DOX-PEC-NP) or liposome (DOX-LIP). In vitro anticancer study showed marked accumulation of doxorubicin in different tumor cells as well as reversal of MDR in HepG2/ADR cells and MCF-7/ADR cells caused by treatment of DOX-PEC-NC. In H22 tumor-bearing mice, DOX-PEC-NC showed higher anticancer efficacy and lower toxicity than doxorubicin. DOX-PEC-NC can improve anticancer activity and reduce side effect of doxorubicin due to increased intracellular accumulation and reversal of MDR in tumor cells, which may be a promising nanoscale drug delivery vehicle for chemotherapeutic agents.


Assuntos
Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Nanopartículas/química , Pectinas/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Nanopartículas/ultraestrutura , Baço/patologia , Timo/patologia
6.
Food Chem ; 330: 127280, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540520

RESUMO

We investigated changes in the chemical composition of WPI as a result of heating (60 °C, 72 h) with SBP in solution (pH 6.75). The concentration of WPI was kept at a constant (3%), whereas the level of SBP was varied at 1, 1.5, and 3%. The reaction products were examined using the Ellman's reagent, ninhydrin assay, and gel electrophoresis. The results demonstrated that the losses of the free sulfhydryl (-SH) and primary amine (-NH2) contents in WPI were less severe compared to those occurring in the dry-state at similar conditions (mass ratio, temperature, and reaction duration). The mixtures were used as emulsifiers in an O/W emulsion system at pH 3.20 and 6.75 and showed an improved ability to stabilize the average size of the droplets than WPI alone at acidic pH. The mixtures at higher levels of SBP, ≥ 1.5%, however, adversely affected the emulsion stability at neutral pH.


Assuntos
Emulsificantes/química , Emulsões/química , Pectinas/química , Proteínas do Soro do Leite/química , Beta vulgaris/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Temperatura , Proteínas do Soro do Leite/isolamento & purificação
7.
Food Chem ; 331: 127203, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32574943

RESUMO

Effects of high hydrostatic pressure (HHP) (50, 100, 150, 200 and 250 MPa) pretreatment on water mobility and distribution, drying duration, microstructure, color, cell wall fraction and tissue structure of strawberry slices were investigated. HHP significantly increased water mobility of the strawberry slices, resulting in the reduction of drying duration by 9-24%. As the pretreatment pressure was increased, redness value and anthocyanin content continuously increased, soluble pectin (SBP) content increased and then decreased, while the contents of protopectin (PTP) and cellulose decreased. After the HHP pretreatment, chromoplasts and moisture was distributed more uniformly in the strawberry slices. Microscopy images showed the formation of microscopic holes or channels in the matrix and the breakdown of tissue structure by HHP. Results suggested HHP pretreatment disrupted the integrity of the fresh strawberry which enhanced the drying efficiency and migration of the chromoplasts during the vacuum-freeze drying process.


Assuntos
Fragaria/química , Liofilização , Antocianinas/química , Antocianinas/metabolismo , Celulose/química , Cor , Fragaria/metabolismo , Pressão Hidrostática , Espectroscopia de Ressonância Magnética , Pectinas/química , Pectinas/metabolismo , Água/química
8.
An Acad Bras Cienc ; 92(1): e20180609, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267306

RESUMO

The present study investigated the encapsulation of ß-galactosidase in carrageenan, pectin and its hybrid hydrogels by using the ionotropic gelation method. The material obtained was characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG/DTG) and scanning electron microscopy (SEM). The effects of pH, temperature and storage time were evaluated in terms of the catalytic activity of the free and encapsulated enzyme. Addition studies were conducted evaluating the performance of catalytic activity in vitro conditions. Carrageenan, pectin and hybrid hydrogels presented encapsulation efficiency of 58 ± 1%, 72 ± 1% and 77 ± 2%, respectively. The pectin hydrogel showed the higher ß-galactosidase activity in pH and temperature tests. However, the carrageenan hydrogel exhibited best stability after been stored for three months. Carrageenan and pectin hydrogels were 2.0 and 2.4 times more efficiently than commercial tablet in the releasing ß-galactosidase under in vitro conditions, respectively. The results suggest that pectin and carrageenan hydrogels may be useful for the development of new formulation of ß-galactosidase.


Assuntos
Carragenina/química , Portadores de Fármacos/química , Pectinas/química , beta-Galactosidase/química , Varredura Diferencial de Calorimetria , Química Farmacêutica , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Tecnologia Farmacêutica
9.
Food Chem ; 321: 126706, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32234636

RESUMO

The purpose of this study was to fabricate ternary complexes composed of pea protein isolate (PPI), high methoxyl pectin (HMP) and individual surfactants including rhamnolipid (Rha), tea saponin (TS) and Ethyl lauroyl arginate (LAE), for the delivery of resveratrol (Res). A combination of electrostatic attraction and hydrophobic interaction was dominantly responsible for the formation of HMP-surfactant-PPI complexes. The physicochemical properties of the ternary complexes were affected by surfactant types as well as mass ratios of individual surfactant to PPI. HMP-Rha-PPI1:1, HMP-TS-PPI1:1 and HMP-LAE-PPI1:25 complexes had higher denaturation temperatures of 82.78 ± 0.31, 80.21 ± 0.02 and 79.98 ± 0.86 ℃, respectively. The HMP-Rha-PPI1:1 ternary complex could be an effective delivery system, which were effective to retard photo- and thermal- degradation of Res as well as delayed the release of Res in in vitro digestion.


Assuntos
Glicolipídeos/química , Proteínas de Ervilha/química , Pectinas/química , Resveratrol/química , Tensoativos/química , Interações Hidrofóbicas e Hidrofílicas , Saponinas/química
10.
Food Chem ; 321: 126707, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244134

RESUMO

Mealiness is one of the most important textural failure of apple fruit and four patterns of mealiness involving five apple cultivars were identified as the rapid, moderate, slow and none, requiring 3, 7, 14, 49 days at 25 °C, respectively. In comparison with the non-mealy 'Fuji' apple, parenchyma cells of mealy apples became detached and remained intact. Highly methyl-esterified homogalacturonan was strongly immunolabeled in the cell wall of slow and non-mealy apples. The mobility of water was enhanced in the cell wall during mealiness. Principal components analysis of FTIR spectra discriminated the cell wall materials (CWM) based on the mealiness progress. Heavy loss of CWM and its water-insoluble fractions but limited increase of water-soluble fractions, and the increase of crystalline micelles of CWM were closely associated with the mealiness progress. Overall, the occurrence of mealiness might attribute to structural, physical and biochemical modifications of CWM during tissue senescence.


Assuntos
Parede Celular/química , Malus/química , Pectinas/química , Frutas/química , Refeições
11.
Ecotoxicol Environ Saf ; 194: 110369, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32135380

RESUMO

Polysaccharides are the main components of plant cell walls in which they make an important contribution to cadmium (Cd) fixation. However, knowledge regarding the role of root cell wall polysaccharides in Cd accumulation in low-Cd cultivars is limited. Here, we compared the differences in root cell wall polysaccharides between two cultivars of Brassica chinensis L. (pakchoi) with different Cd accumulation abilities. A hydroponic experiment was conducted using low- (Huajun 2) and high-Cd (Hanlv) pakchoi cultivars. We investigated Cd subcellular distribution and Cd accumulation in cell wall polysaccharides and examined polysaccharide modifications in root cell walls by Fourier transform infrared spectroscopy. A Cd adsorption kinetics experiment was conducted to examine the connection between Cd-induced polysaccharide modifications and Cd fixation by cell walls. Amounts of Cd were significantly higher and more Cd was bound to cell walls in the roots of Huajun 2 than in those of Hanlv. These results indicated that the greater Cd retention capacity of the root cell wall in Huajun 2 accounted for the low Cd accumulation in the shoot. Up to 79.4% and 32.1% of cell-wall-bound Cd was found in the pectin and hemicellulose 1, respectively, and higher amounts of Cd were found in these cell wall components of Huajun 2 than in those of Hanlv. Exposure to Cd significantly increased amounts of pectin and hemicellulose 1 in both pakchoi cultivars, but the pectin levels were significantly higher in Huajun 2 than in Hanlv. Huajun 2 had higher pectin methylesterase (PME) activity and a lower degree of pectin methyl-esterification (DM) than Hanlv, although Cd treatments resulted in increased PME activity and decreased DM in both cultivars. The higher Cd treatment (44.5 µM) resulted in enhanced Cd-binding capacity in root cell walls of the two cultivars with higher Cd adsorption levels in the root cell wall of Huajun 2. These results indicate that differences in the amount of cell wall polysaccharide and DM play key roles in establishing the genotypic differences underlying Cd accumulation in pakchoi. These findings conduce to a better understanding of the physiological mechanisms underlying low Cd accumulation in pakchoi and the breeding of new, low-Cd pakchoi cultivars.


Assuntos
Brassica/metabolismo , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Adsorção , Parede Celular/metabolismo , Hidroponia , Pectinas/química , Raízes de Plantas/metabolismo , Polissacarídeos/metabolismo , Poluentes do Solo/análise
12.
Food Chem ; 320: 126631, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32222660

RESUMO

Effect of superfine grinding on pectin extraction was investigated. Sunflower heads were grinded into microparticles of ~50 µm, thus pectin chains were fully exposed due to cell wall breakdown. A good pectin yield of 14.5 ± 0.36% (w/w) was subsequently achieved at mild conditions (pH 5.0, 25 °C, 2 h) associated with 0.8% (w/v) sodium citrate (SC). However, the molecule weight of pectin was greatly reduced (Mw = 7.87 ± 0.21 kDa) due to the action of endo-pectinases. With heating (pH 5.0, 85 °C for 20 min, 25 °C for 1.5 h) the endo-pectinases were effectively inhibited, thus Mw was increased to 338.07 ± 12.37 kDa. With superfine grinding, pectin extracted with different conditions presented various properties. Pectin extracted at pH 2.5 had higher esterification degree (DE, ~40%) and gelled at 3% (w/v) concentration. In contrast, pectin extracted under mild condition with low DE (21%) cannot gel at the same concentration. Conclusively, superfine grinding has potential application in pectin extraction.


Assuntos
Helianthus/química , Pectinas/química , Esterificação , Temperatura Alta , Peso Molecular , Pectinas/isolamento & purificação
13.
J Food Sci ; 85(4): 989-997, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32198761

RESUMO

Protein-rich beverages have gained significant attention in recent years. It is a challenge to produce whey protein beverages with high stability, good transparency, and a smooth mouthfeel. The polysaccharide (PS)-protein complex might help the food industry overcome these obstacles. In this study, soybean soluble polysaccharide (SSPS) and high methoxylated pectin (HMP, a traditional PS) are used, at different ratios to the protein, to improve the colloidal stability of the acidified whey protein solution. Both heated and unheated complexes were studied. SSPS-whey protein complexes have shown exceptional stabilities in all ratios while HMP-whey protein complexes revealed coacervation after 72 hr of storage. The prepared complexes exhibited comparable sizes and ζ-potentials. The SSPS-whey protein complexes were less turbid than HMP-whey protein complexes at similar PS to protein ratios. Results also show that greater repulsive interactions occurred in SSPS-whey protein complexes when compared to HMP-whey protein complexes, as examined by free thiol content and intrinsic fluorescence intensity measurements. PRACTICAL APPLICATION: It is a challenge to produce whey protein isolate (WPI) beverages with high stability, good transparency, and smooth mouthfeel. The polysaccharide (PS)-protein complex might help the food industry overcome these obstacles. We have demonstrated that soybean soluble polysaccharide (SSPS), at [SSPS]:[acWPI] ratios of 1:2 to 1:30, can significantly improve the colloidal stability of the acidified whey protein beverages. This SSPS-whey protein system could be used as a stable beverage base for a variety of beverages.


Assuntos
Bebidas/análise , Polissacarídeos/química , Soja/química , Proteínas do Soro do Leite/química , Ácidos/química , Coloides/química , Carboidratos da Dieta/análise , Manipulação de Alimentos , Pectinas/química
14.
Food Chem ; 318: 126476, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32143132

RESUMO

A pilot-scale extraction of sunflower pectin with 0.74% (w/v) sodium citrate (72 °C, 194 min) and different procedures of purification including alcohol precipitation, ultrafiltration (UFDF) and microfiltration (MFDF) with diafiltration were carried out. Considering the alcohol treatment, the yields were similar at laboratory and pilot-scale (~8.9%), demonstrating the efficiency of the scale-up. With respect to membrane processes, the best results were obtained with UFDF, showing the highest yield (13.3%) and pectin concentration higher than 90%. In all cases, pectins presented very low amount (~1%) of glucose and mannose, monosaccharides not included in the pectin structure. Detailed NMR analysis and functional properties (emulsifying and viscosity) that were also assessed corroborated the good quality of UFDF obtained pectin. These results point out that the obtainment of sunflower pectin of good quality can be achieved at pilot-scale by the extraction with sodium citrate and purification with membrane separation, eco-friendly alternatives to conventional procedures.


Assuntos
Helianthus/química , Pectinas/química , Pectinas/isolamento & purificação , Fracionamento Químico , Emulsificantes/química , Citrato de Sódio/química , Ultrafiltração/métodos , Viscosidade
15.
Nat Commun ; 11(1): 1449, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193375

RESUMO

Pollen's practically-indestructible shell structure has long inspired the biomimetic design of organic materials. However, there is limited understanding of how the mechanical, chemical, and adhesion properties of pollen are biologically controlled and whether strategies can be devised to manipulate pollen beyond natural performance limits. Here, we report a facile approach to transform pollen grains into soft microgel by remodeling pollen shells. Marked alterations to the pollen substructures led to environmental stimuli responsiveness, which reveal how the interplay of substructure-specific material properties dictates microgel swelling behavior. Our investigation of pollen grains from across the plant kingdom further showed that microgel formation occurs with tested pollen species from eudicot plants. Collectively, our experimental and computational results offer fundamental insights into how tuning pollen structure can cause dramatic alterations to material properties, and inspire future investigation into understanding how the material science of pollen might influence plant reproductive success.


Assuntos
Ciência dos Materiais , Microgéis/química , Pólen/química , Biomimética/métodos , Química Computacional , Epitopos/química , Epitopos/imunologia , Esterificação , Dureza , Hidrólise , Hidróxidos/química , Microscopia de Fluorescência , Pectinas/química , Pectinas/imunologia , Pólen/imunologia , Polinização/fisiologia , Compostos de Potássio/química , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Nature ; 579(7800): 561-566, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32214247

RESUMO

Species that propagate by sexual reproduction actively guard against the fertilization of an egg by multiple sperm (polyspermy). Flowering plants rely on pollen tubes to transport their immotile sperm to fertilize the female gametophytes inside ovules. In Arabidopsis, pollen tubes are guided by cysteine-rich chemoattractants to target the female gametophyte1,2. The FERONIA receptor kinase has a dual role in ensuring sperm delivery and blocking polyspermy3. It has previously been reported that FERONIA generates a female gametophyte environment that is required for sperm release4. Here we show that FERONIA controls several functionally linked conditions to prevent the penetration of female gametophytes by multiple pollen tubes in Arabidopsis. We demonstrate that FERONIA is crucial for maintaining de-esterified pectin at the filiform apparatus, a region of the cell wall at the entrance to the female gametophyte. Pollen tube arrival at the ovule triggers the accumulation of nitric oxide at the filiform apparatus in a process that is dependent on FERONIA and mediated by de-esterified pectin. Nitric oxide nitrosates both precursor and mature forms of the chemoattractant LURE11, respectively blocking its secretion and interaction with its receptor, to suppress pollen tube attraction. Our results elucidate a mechanism controlled by FERONIA in which the arrival of the first pollen tube alters ovular conditions to disengage pollen tube attraction and prevent the approach and penetration of the female gametophyte by late-arriving pollen tubes, thus averting polyspermy.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/metabolismo , Fertilização , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Óxido Nítrico/metabolismo , Óvulo Vegetal/metabolismo , Pectinas/metabolismo , Fosfotransferases/metabolismo , Tubo Polínico/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Óvulo Vegetal/citologia , Pectinas/química , Tubo Polínico/citologia
17.
Int J Nanomedicine ; 15: 333-346, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021183

RESUMO

Purpose: Wound healing, especially of extensive full-thickness wounds, is one of the most difficult problems in clinical studies. In this study, we prepared a novel substance P (SP)-delivery system using zeolite imidazolate framework-8 (ZIF-8) nanoparticles. Methods: We synthesized ZIF-8 nanoparticles using a modified biomimetic mineralization method. We then coated SP-loaded ZIF-8 nanoparticles (SP@ZIF-8) with polyethylene glycol-thioketal (PEG-TK) to fabricate SP@ZIF-8-PEG-TK nanoparticles, and encapsulated them in injectable hydrogel composed of sodium alginate and pectin and cross-linked using calcium chloride. The final hydrogel wound dressing containing SP@ZIF-8-PEG-TK nanoparticles was called SP@ZIF-8-PEG-TK@CA. Results: The fabricated ZIF-8 nanoparticles had high SP-loading efficiency. SP-release assay showed that the SP@ZIF-8-PEG-TK nanoparticles maintained drug activity and showed responsive release under stimulation by reactive oxygen species. The SP@ZIF-8-PEG-TK nanoparticles promoted proliferation of human dermal fibroblasts, up-regulated expression levels of inflammation-related genes in macrophages, and exhibited favorable cytocompatibility in vitro. Full-thickness excision wound models in vivo confirmed that SP@ZIF-8-PEG-TK@CA dressings had excellent wound-healing efficacy by promoting an early inflammatory response and subsequent M2 macrophage polarization in the wound-healing process. Conclusion: In conclusion, these findings indicated that SP@ZIF-8-PEG-TK@CA dressings might be useful for wound dressing applications in the clinic.


Assuntos
Bandagens , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Substância P/administração & dosagem , Cicatrização/efeitos dos fármacos , Zeolitas/química , Alginatos/química , Animais , Cloreto de Cálcio/química , Proliferação de Células/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Sistemas de Liberação de Medicamentos/métodos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogéis/química , Imidazóis/química , Camundongos Endogâmicos BALB C , Nanopartículas/administração & dosagem , Pectinas/química , Polietilenoglicóis/química , Substância P/farmacocinética
18.
J Photochem Photobiol B ; 204: 111767, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006893

RESUMO

Colon carcinoma is a recurring type of cancer that affects the intestine epithelial with a poor survival rate. It was already proven the anticancer property of hesperidin in various cancers but the bioavailability hesperidin is poor, which hinders the hesperidin usage. In this investigation we synthesized hesperidin loaded Zn2+@ SA/PCT nanocomposites and assessed its anticancer potential against colon cancer (HCT116) cells. Hesperidin loaded Zn2+@ SA/PCT nanocomposites were characterized using Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis. The drug releasing capacity and cytotoxic property was assessed via drug releasing assay, MTT assay with HCT116 cells. The anticancer potency of hesperidin nanocomposites were evaluated with TUNEL, DAPI staining, reactive oxygen species (ROS) generation assay and it is confirmed with flow cytometry analysis of MMP disruption in colon cancer (HCT116) cell line. Further the immunoblotting analysis of cysteine proteases Caspases 3, 9, PARP, proapoptotic protein Bax and antiapoptotic protein Bcl2 were performed. The results of FTIR, XRD and electroscopic analyses confirmed the synthesized hesperidin nanocomposites accomplish the properties of potent nanodrug and the MTT assay authentically confirmed that the synthesized hesperidin nanocomposite inhibited the HCT116 cell growth, and the results of fluorescent staining proved that the hesperidin nanocomposite induced the apoptotic mediated cell necrosis via promoting the expression of apoptotic proteins thereby induced the apoptosis in colon cancer (HCT116) cells. Hence, it was concluded that the, hesperidin loaded nanocomposites persuasively inhibited proliferation of colon carcinoma cell and induced apoptosis in in vitro condition.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Hesperidina/química , Nanocompostos/química , Alginatos/química , Antineoplásicos Fitogênicos/química , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Células HCT116 , Hesperidina/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Pectinas/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Zinco/química
19.
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
20.
J Agric Food Chem ; 68(4): 1051-1063, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31910005

RESUMO

Glycyrrhizic acid (GA) and GA nanofibrils (GN) have been shown to be efficient natural emulsifiers for formation and stabilization of food emulsions. In this work, the emulsion properties of GN in the presence of soy protein isolate-pectin complex nanoparticles (SPNPs) were studied to understand the impact of the nanofibril-nanoparticle interactions on emulsion stabilization. In the presence of low GN concentrations (0.1-0.5 wt %), the synergy in reducing the interfacial tension was observed due to SPNPs-GN complexation in the bulk and at the interface by hydrogen bonding, endowing the prepared emulsions with an overall smaller droplet size. However, obvious flocculation and clustering of oil droplets occurred in these emulsions (especially at 0.25 and 0.5 wt % GN), which are probably induced by a depletion mechanism. At high GN concentrations (1-2 wt %), due to the preferential adsorption, the GN mainly dominated the interface and the subsequent formation and properties of emulsions. Accordingly, the self-standing emulsion gels were obtained, showing a small droplet size with d32 of about 1.0-1.5 µm, homogeneous appearance and microstructure, and encouraging rheological properties including high gel strength, shear sensitivity, and good thixotropic recovery. This is mainly attributed to the formation of a fibrillar hydrogel network in the continuous phase as well as around the droplet surfaces.


Assuntos
Ácido Glicirrízico/química , Nanofibras/química , Nanopartículas/química , Pectinas/química , Proteínas de Soja/química , Adsorção , Emulsões/química , Géis/química , Tamanho da Partícula
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