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1.
J Microencapsul ; 37(3): 220-229, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32039640

RESUMO

Aim: A novel folated pluronic F127 (FA-F127) was synthesised, so as to modify liposomes with FA group on the surface, and evaluate the effects of FA-F127 modification on the properties of the modified liposomes.Methods: FA was linked to one end of pluronic F127, via the terminal OH group, to obtain FA-F127 and the structure was characterised. FA-F127 modified curcumin liposomes (cur-FA-F127-Lps) were prepared. The physicochemical characteristics of cur-FA-F127-Lps, including morphology and particle size, were studied. The in vitro cytotoxicity of cur-FA-F127-Lps against KB cancer cells was determined by MTT tests.Results: The effects of FA-F127 modification on the average particle size, PDI, curcumin encapsulation efficiency and microstructure were not significant. Compared with nonfolated F127 liposomes (cur-F127-Lps), cur-FA-F127-Lps exhibited significantly higher cytotoxicity towards KB cells.Conclusions: Folic acid modified liposomes provide a novel strategy to improve the chemotherapeutic efficacy of hydrophobic bioactive compounds.


Assuntos
Curcumina , Citotoxinas , Neoplasias/tratamento farmacológico , Poloxâmero , Linhagem Celular Tumoral , Curcumina/química , Curcumina/farmacocinética , Curcumina/farmacologia , Citotoxinas/química , Citotoxinas/farmacocinética , Citotoxinas/farmacologia , Humanos , Lipossomos , Neoplasias/metabolismo , Neoplasias/patologia , Poloxâmero/análogos & derivados , Poloxâmero/química , Poloxâmero/farmacocinética , Poloxâmero/farmacologia
2.
Molecules ; 20(8): 14293-311, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26251892

RESUMO

Curcumin is a multifunctional and natural agent considered to be pharmacologically safe. However, its application in the food and medical industry is greatly limited by its poor water solubility, physicochemical instability and inadequate bioavailability. Nanoliposome encapsulation could significantly enhance the solubility and stability of curcumin. Curcumin nanoliposomes exhibited good physicochemical properties (entrapment efficiency = 57.1, particle size = 68.1 nm, polydispersity index = 0.246, and zeta potential = -3.16 mV). Compared with free curcumin, curcumin nanoliposomes exhibited good stability against alkaline pH and metal ions as well as good storage stability at 4 °C. Curcumin nanoliposomes also showed good sustained release properties. Compared with free curcumin, curcumin nanoliposomes presented an equal cellular antioxidant activity, which is mainly attributed to its lower cellular uptake as detected by fluorescence microscopy and flow cytometry. This study provide theoretical and practical guides for the further application of curcumin nanoliposomes.


Assuntos
Antioxidantes/farmacologia , Curcumina/química , Curcumina/farmacologia , Nanopartículas/química , Células CACO-2 , Preparações de Ação Retardada , Estabilidade de Medicamentos , Endocitose/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Íons , Lipossomos , Metais/farmacologia , Microscopia de Fluorescência , Nanopartículas/ultraestrutura , Tamanho da Partícula , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
3.
Int J Biol Macromol ; 262(Pt 2): 130143, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367775

RESUMO

A novel carrier comprised of ethanol- and alkali-modified cellulosic pomelo pith matrix coated with alginate was developed to improve viability while enabling gastrointestinal release of probiotics. Scanning electron microscopy imaging revealed the agricultural byproduct had a honeycomb-structured cellulose framework, enabling high loading capacity of the probiotic Lactobacillus plantarum up to 9 log CFU/g. Ethanol treatment opened up pores with an average diameter of 97 µm, while alkali treatment increased swelling and porosity, with an average pore size of 51 µm. The survival rate through the stomach was increased from 89.76 % to 91.08 % and 91.24 % after ethanol and alkali modification, respectively. The control group displayed minimal release in the first 4 h followed by a burst release. Both ethanol modification and alkali modification resulted in constant linear release over time. The release time was prolonged when decreasing the width of the pomelo peel rolls from 10 mm to 5 mm while keeping the volume of the peel constant. After 8 weeks of refrigerated storage, the cellulose-encapsulated probiotics retained viability above 7 log CFU/g. This study demonstrates the potential of the structurally intact, sustainably-sourced cellulosic pomelo pith for probiotic encapsulation and controlled delivery.


Assuntos
Alginatos , Probióticos , Celulose , Preparações de Ação Retardada , Álcalis , Etanol , Viabilidade Microbiana
4.
J Dairy Sci ; 96(4): 2061-2070, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23375971

RESUMO

Liposomes loaded with positively charged lactoferrin (LF) were prepared from milk fat globule membrane-derived phospholipids using a thin-layer dispersion method. The entrapment efficiency of LF in the liposomes and the stability during in vitro gastrointestinal digestion were characterized and examined using dynamic light scattering, transmission electron microscopy, and PAGE. The entrapment efficiency of LF encapsulated in the liposomes was about 46%. The entrapped LF remained unchanged as a function of time and pepsin concentration when the liposome samples were digested in a simulated gastric environment, suggesting that the liposomes prepared from milk fat globule membrane-derived phospholipids were stable and protected the entrapped LF from pepsin hydrolysis. In simulated intestinal fluid, the entrapped LF was more susceptible to hydrolysis by the protease in pancreatin, as shown by changes in the diameter and membrane structure of the liposomes. The release of free fatty acids from the liposomes during digestion in simulated intestinal fluid revealed that the phospholipids in the liposomes were partly hydrolyzed by pancreatic lipase. It was suggested that liposomes may prevent the gastric degradation of LF and reduce the rate of hydrolysis of LF in intestinal conditions.


Assuntos
Digestão , Glicolipídeos/química , Glicoproteínas/química , Lactoferrina/metabolismo , Lipossomos , Fosfolipídeos , Animais , Fenômenos Químicos , Estabilidade de Medicamentos , Suco Gástrico , Concentração de Íons de Hidrogênio , Hidrólise , Técnicas In Vitro , Lactoferrina/administração & dosagem , Gotículas Lipídicas , Lipólise , Lipossomos/química , Lipossomos/metabolismo , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Fosfolipídeos/química , Fosfolipídeos/metabolismo
5.
Int J Mol Sci ; 14(10): 19763-73, 2013 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-24084723

RESUMO

The complex nanoliposomes encapsulating both a hydrophilic drug vitamin C (vit C) and hydrophobic drug medium-chain fatty acids (MCFAs) was prepared by combining double emulsion method with dynamic high pressure microfluidization. The complex nanoliposomes was further freeze-dried under -86 °C for 48 h with sucrose at the sucrose/lipids ratio of 2:1(w/w) in order to enhance its stability. The freeze-dried complex nanoliposomes under the suitable conditions exhibited high entrapment efficiency of MCFAs (44.26 ± 3.34)%, relatively high entrapment efficiency of vit C (62.25 ± 3.43)%, low average size diameter (110.4 ± 7.28) nm and good storage stability at 4 °C for 60 days with slight changes in mean particle diameter and drug entrapment efficiencies. The results of transmission electron microscopy of freeze-dried complex nanoliposomes also showed that the freeze-dried samples with sucrose were stable without great increase in their particle sizes and without destroying their spherical shape. The results indicated that sucrose presented well protection effects in MCFAs-vit C complex nanoliposomes, suggesting the possibility of further usage in commercial liposomes.


Assuntos
Ácido Ascórbico/química , Ácidos Graxos/química , Lipossomos/química , Nanopartículas/química , Armazenamento de Medicamentos , Liofilização/métodos , Tamanho da Partícula
6.
Carbohydr Polym ; 316: 121059, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321742

RESUMO

Organic dyes, such as methyl orange (MO), Congo red (CR), crystal violet (CV) and methylene blue (MB), are common organic pollutants existing in wastewater. Therefore, the exploration of bio-based adsorbents for the efficient removal of organic dyes from wastewater has gained many attentions. Here, we report a PCl3-free synthetic method for the synthesis of phosphonium-containing polymers, in which the prepared tetrakis(2-carboxyethyl) phosphonium chloride-crosslinked ß-cyclodextrin (TCPC-ß-CD) polymers were applied to the removal of dyes from water. The effects of contact time, pH (1-11), and dye concentration were investigated. The selected dye molecules could be captured by the host-gest inclusion of ß-CD cavities, and the phosphonium and carboxyl groups in the polymer structure would respectively facilitate the removal of cationic dyes (MB and CV) and anionic dyes (MO and CR) via electrostatic interactions. In a mono-component system, over 99 % of MB could be removed from water within the first 10 min. Based on the Langmuir model, the calculated maximum adsorption capacities of MO, CR, MB, and CV were 180.43, 426.34, 306.57, and 470.11 mg/g (or 0.55, 0.61, 0.96 and 1.15 mmol/g), respectively. Additionally, TCPC-ß-CD was easily regenerated using 1 % HCl in ethanol, and the regenerative adsorbent still showed high removal capacities for MO, CR, and MB even after seven treatment cycles.


Assuntos
Poluentes Químicos da Água , beta-Ciclodextrinas , Águas Residuárias , Poluentes Químicos da Água/química , Corantes/química , beta-Ciclodextrinas/química , Polímeros , Vermelho Congo , Adsorção , Azul de Metileno/química , Concentração de Íons de Hidrogênio
7.
Carbohydr Polym ; 291: 119582, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698399

RESUMO

The quality parameters of mangoes change during ripening, which has a vital impact on processing characteristics. Effects of ripening stage (four stages from the lowest to highest degree-RS-1, RS-2, RS-3, RS-4) on cell wall polysaccharides and far infrared drying kinetics of mangoes were investigated. As ripening progressed, the water-soluble pectin contents increased by 213.5%; while the chelate-, sodium carbonate-soluble pectin and hemicellulose contents decreased by 44.0%, 59.5% and 65.8%, respectively. Moreover, the molecular weight reduction confirmed the degradation of pectin. These further caused the alteration of cell wall structure and changes in water distribution. Meanwhile, the drying time of mangos with different ripeness were in the order: RS-3 > RS-4 > RS-2 > RS-1. It correlated with the degradation of cell wall polysaccharides, the destruction of cell wall and the increases in free water during ripening. The ripeness classification could effectively improve the uniformity and efficiency of fruits drying processing.


Assuntos
Mangifera , Pectinas , Parede Celular/química , Celulose/metabolismo , Frutas/química , Cinética , Pectinas/química , Polissacarídeos/metabolismo , Água/análise
8.
Br J Nutr ; 106(9): 1330-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21733323

RESUMO

Medium-chain fatty acids (MCFA) are widely used in diets for patients with obesity. To develop a delivery system for suppressing dietary fat accumulation into adipose tissue, MCFA were encapsulated in nanoliposomes (NL), which can overcome the drawbacks of MCFA and keep their properties unchanged. In the present study, crude liposomes were first produced by the thin-layer dispersion method, and then dynamic high-pressure microfluidisation (DHPM) and DHPM combined with freeze-thawing methods were used to prepare MCFA NL (NL-1 and NL-2, respectively). NL-1 exhibited smaller average size (77.6 (SD 4.3) nm), higher zeta potential (- 40.8 (SD 1.7) mV) and entrapment efficiency (73.3 (SD 16.1) %) and better stability, while NL-2 showed narrower distribution (polydispersion index 0.193 (SD 0.016)). The body fat reduction property of NL-1 and NL-2 were evaluated by short-term (2 weeks) and long-term (6 weeks) experiments of mice. In contrast to the MCFA group, the NL groups had overcome the poor palatability of MCFA because the normal diet of mice was maintained. The body fat and total cholesterol (TCH) of NL-1 (1.54 (SD 0.30) g, P = 0.039 and 2.33 (SD 0.44) mmol/l, P = 0.021, respectively) and NL-2 (1.58 (SD 0.69) g, P = 0.041 and 2.29 (SD 0.38) mmol/l, P = 0.015, respectively) significantly decreased when compared with the control group (2.11 (SD 0.82) g and 2.99 (SD 0.48) mmol/l, respectively). The TAG concentration of the NL-1 group (0.55 (SD 0.14) mmol/l) was remarkably lower (P = 0.045) than the control group (0.94 (SD 0.37) mmol/l). No significant difference in weight and fat gain, TCH and TAG was detected between the MCFA NL and MCFA groups. Therefore, MCFA NL could be potential nutritional candidates for obesity to suppress body fat accumulation.


Assuntos
Tecido Adiposo/metabolismo , Gorduras na Dieta/metabolismo , Ácidos Graxos/administração & dosagem , Metabolismo dos Lipídeos , Lipídeos/sangue , Nanotecnologia/métodos , Obesidade/tratamento farmacológico , Animais , Colesterol/sangue , Ácidos Graxos/metabolismo , Ácidos Graxos/uso terapêutico , Lipossomos , Masculino , Camundongos , Camundongos Endogâmicos , Obesidade/metabolismo , Paladar , Triglicerídeos/sangue
9.
J Microencapsul ; 28(8): 783-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21970656

RESUMO

To develop an easy-energy-supply agent, medium-chain fatty acids (MCFAs) liposomes were prepared by thin-layer dispersion, freeze-thawing and dynamic high pressure microfluidization (DHPM)-freeze-thawing methods. Results showed that MCFAs nanoliposomes obtained by the novel method (DHPM-freeze-thawing) exhibited a smaller size (72.6 ± 4.9 nm), narrower size distribution (PDI = 0.175 ± 0.005), higher zeta potential (-41.27 ± 1.16 mV) and entrapment efficiency (45.9 ± 6.0%) compared to the other two methods. In the weight-loaded swimming test of the mice, the high-dose group of MCFAs nanoliposomes indicated a significantly longer swimming time (105 ± 31 min, p < 0.05), a lower serum urea nitrogen (839.5 ± 111.9 mg/L, p < 0.05) and blood lactic acid (5.7 ± 1.0 mmol/L, p ≤ 0.001), and a higher hepatic glycogen (15.0 ± 3.6 mg/g, p ≤ 0.001) than those of the control group (53 ± 13 min, 1153.6 ± 102.5 mg/L, 12.5 ± 1.9 mmol/L and 8.8 ± 3.3 mg/g, respectively). However, no significant difference was found between the high-dose group and MCFAs group. The results suggested that MCFAs nanoliposomes could be used as a potential easy-energy-supply agent.


Assuntos
Ácidos Graxos/administração & dosagem , Ácidos Graxos/metabolismo , Lipossomos/química , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal , Metabolismo Energético , Congelamento , Glicogênio/metabolismo , Ácido Láctico/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Natação
10.
Food Chem ; 343: 128402, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33406572

RESUMO

A new method was investigated to decline the antigenicity of ß-Lactoglobulin (ß-LG) by site specifically conjugating ß-LG at the N-terminus with 5 kDa and 10 kDa monomethoxy polyethylene glycol propyl aldehyde (mPEG-ALD). The optimal reaction conditions were molar ratio of 1:10 (ß-LG:mPEG-ALD), reaction time for 16 h, and pH 5.0, and the content of mono-PEGylated ß-LG was 51.3%. The results showed that mono-PEGylated ß-LG with molecular mass of 23.2 kDa and 28.5 kDa. The peptide fragments of mPEG5kDa-ALD-ß-LG produced the same sequence pattern of ß-LG except for the absence of one peptides f(1-14), indicating that α-amino group at the N-terminal was selectively modified. Furthermore, the conformation of modified ß-LG underwent into slight change. The antigenicity of mPEG5kDa-ALD-ß-LG and mPEG10kDa-ALD-ß-LG decreased from 144.4 µg/mL to 66.7 and 39.0 µg/mL respectively. It was speculated that the steric hindrance effect of PEG was the main reason for the decline of antigenicity of ß-LG.


Assuntos
Lactoglobulinas/química , Polietilenoglicóis/química , Animais , Antígenos/química , Antígenos/imunologia , Bovinos , Ensaio de Imunoadsorção Enzimática , Lactoglobulinas/imunologia , Peso Molecular , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
J Liposome Res ; 20(3): 183-90, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19848446

RESUMO

In this study, medium-chain fatty acid (MCFA) liposomes were prepared by the film ultrasonic dispersion, modified ethanol injection, and reverse-phase evaporate methods. The results indicated that the liposomes prepared by the thin-film ultrasonic dispersion method had a high entrapment efficiency of 82.7% and a good distribution in size diameters. The MCFA liposomes were freeze-dried and the optimal preparation conditions of freeze-drying were as follows: The cryoprotectants were mannitol and sucrose (1:1 w/w), the hydrated medium was distilled water, and the freeze-drying time was 48 hours. Under these conditions, the freeze-dried MCFA liposomes had a perfect appearance, a small particle size, and high encapsulation efficiency. The mean diameters were 251.1 and 265.3 nm, and the encapsulation efficiencies were 80.5 and 79.2% for freshly prepared and reconstituted liposomes, respectively.


Assuntos
Lipossomos/síntese química , Caprilatos/química , Fenômenos Químicos , Ácidos Decanoicos/química , Liofilização/métodos , Lipossomos/química , Microscopia Eletrônica de Transmissão
12.
Adv Mater ; 32(23): e2001383, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32350974

RESUMO

Water transport rate in network membranes is inversely correlated to thickness, thus superior permeance is achievable with ultrathin membranes prepared by complicated methods circumventing nanofilm weakness and defects. Conferring ultrahigh permeance to easily prepared thicker membranes remains challenging. Here, a tetrakis(hydroxymethyl) phosphonium chloride (THPC) monomer is discovered that enables straightforward modification of polyamide composite membranes. Water permeance of the modified membrane is ≈6 times improved, give rising to permeability (permeance × thickness) one magnitude higher than state-of-the-art polymer nanofiltration membranes. Meanwhile, the membrane exhibits good rejection (RNa2SO4 = 98%) and antibacterial properties under crossflow conditions. THPC modification not only improves membrane hydrophilicity, but also creates additional angstrom-scale channels in polyamide membranes for unimpeded transport of water. This unique mechanism provides a paradigm shift in facile preparation of ultrapermeable membranes with unreduced thickness for clean water and desalination.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Membranas Artificiais , Nylons/química , Nylons/farmacologia , Compostos Organofosforados/química , Permeabilidade , Água/química
13.
Food Res Int ; 123: 623-630, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31285011

RESUMO

ß-lactoglobulin (ß-LG) is one of the main allergens in milk. Polyethylene glycol (PEG) modification (PEGylation) was found to have the ability to reduce the antigenicity of proteins. To determine the effect of site specific PEGylation on ß-LG antigenicity and conformation, we applied 5 kDa methoxy polyethylene glycol-amine (mPEG-NH2) to modify ß-LG at glutamine (Gln) residues under the catalysis of transglutaminase. The antigenicity of ß-LG was measured using rabbit IgG antibodies by indirect competitive ELISA. The result indicated that the antigenicity of ß-LG was decreased from 72.2 µg/mL to 22.7 µg/mL after PEGylation. SDS-PAGE and MALDI-TOF-MS showed that the molecular mass of native ß-LG was about 18.3 kDa while the PEGylated ß-LG had a molecular mass of 23.4 kDa, which meant that mono-PEGylated ß-LG was obtained after PEGylation and purification by cation exchange chromatography. Additionally, the circular dichroism spectrum of the PEGylated ß-LG was approximately superimposed on that of ß-LG and the secondary structure content of ß-LG also had no significant changes after PEGylation, which indicated that the secondary structure of ß-LG was preserved. After PEGylation, the intrinsic fluorescence intensity of ß-LG decreased from 6361 to 5159 while the surface hydrophobicity increased, which indicated that the tertiary structure of ß-LG was slightly changed. PEGylation site analysis result showed that Gln 155 or Gln 159 might be the most possible binding site. In conclusion, the decrease of the antigenicity of ß-LG induced by the PEGylation is mainly due to the steric shielding effect of PEG chain rather than conformational changes of ß-LG.


Assuntos
Alérgenos/química , Alérgenos/imunologia , Glutamina/química , Lactoglobulinas/química , Leite/química , Leite/imunologia , Polietilenoglicóis/química , Animais , Bovinos , Eletroforese em Gel de Poliacrilamida , Glicosilação , Interações Hidrofóbicas e Hidrofílicas , Imunoglobulina G , Lactoglobulinas/imunologia , Espectrometria de Massas , Hipersensibilidade a Leite/imunologia , Modelos Moleculares , Estrutura Secundária de Proteína , Coelhos , Transglutaminases/metabolismo
14.
J Agric Food Chem ; 67(26): 7506-7511, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184879

RESUMO

The poor water solubility and oral bioavailability of many lipophilic polyphenols can be improved through the use of colloidal delivery systems. In this study, a pH-driven method was used to encapsulate curcumin, quercetin, and resveratrol within nanoliposomes. This method is based on the decrease in water-solubility of certain polyphenols when they move from alkaline to acid conditions. However, the chemical stability of some polyphenols is relatively poor under alkaline conditions. For this reason, the impact of pH on the chemical degradation of the three polyphenols was studied. The polyphenols were then encapsulated within nanoliposomes using the pH-driven method and the encapsulation efficiency (EE) and chemical stability were determined. The EE of curcumin, quercetin, and resveratrol in the nanoliposomes was 100, 54, and 93%, respectively. Differences in the EE were mainly attributed to differences in their stability under alkaline conditions. Our results show that the application of this method to other lipophilic polyphenols depends on the impact of pH on their solubility and chemical stability, which needs to be established on a case-by-case basis.


Assuntos
Composição de Medicamentos/métodos , Lipossomos/química , Nanopartículas/química , Polifenóis/química , Disponibilidade Biológica , Curcumina/química , Portadores de Fármacos/química , Concentração de Íons de Hidrogênio , Quercetina/química , Resveratrol/química , Solubilidade
15.
Food Funct ; 10(11): 7239-7252, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31617530

RESUMO

The effect of two plant-based emulsifiers (quillaja saponin, QS and gum arabic, GA) and a polyphenol (tannic acid) on the formation, stability, digestibility, and ß-carotene (BC) bioaccessibility of flaxseed oil-in-water emulsions was investigated. The gastrointestinal behavior of the emulsions was studied using a simulated gastrointestinal tract (GIT) consisting of mouth, stomach, and small intestine regions. In the absence of tannic acid, the initial extent of lipid digestion depended strongly on emulsifier type, with 45% and 76% of the free fatty acids being released after 5 min digestion for QS- and GA-emulsions, respectively. Even so, the lipid droplets were completely digested in both emulsions after 2 h incubation in the small intestine phase. Tannic acid addition (0.01% and 0.1% w/w) slowed down lipid digestion, but did not impact the final extent. The droplets in the QS-emulsions containing 0.1% tannic acid were highly flocculated in the stomach phase. Molecular docking simulations indicated that the interactions between tannic acid and the saponins were mainly driven by hydrogen bonding and hydrophobic interactions. Moreover, they showed that the interactions between tannic acid and QS were stronger at pH 2.5 than at pH 7.0, which would account for the extensive droplet flocculation observed under acidic conditions in the stomach. Emulsifier type and tannic acid addition had no significant influence on BC bioaccessibility. The GA-emulsions exhibited better stability than the QS-emulsions when stored at elevated temperatures (55 °C for 7 days). Tannic acid addition effectively inhibited temperature-induced BC degradation. These results may facilitate the design of more efficacious nutraceutical-loaded functional foods and beverages.


Assuntos
Emulsificantes/química , Plantas/química , Taninos/química , beta Caroteno/química , beta Caroteno/farmacocinética , Disponibilidade Biológica , Reatores Biológicos , Digestão , Emulsões/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular
16.
J Agric Food Chem ; 66(46): 12421-12430, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30372060

RESUMO

There is significant interest in the formulation of liposome-based delivery systems using cheap plant-based commercial sources of lecithin. This study evaluated the impact of phospholipid type on the formation, stability, and curcumin-loading of sunflower liposomes. Four kinds of sunflower lecithin (Sunlipon 50, 65, 75, and 90) with different phosphatidylcholine (PC) levels were used to prepare the liposomes using microfluidization. The particle size, surface charge, microstructure, and stability of the liposomes were determined. All four kinds of lecithin were suitable for fabricating stable liposomes regardless of the PC content. Curcumin was loaded into the liposomes using a newly developed pH-driven method. The loading capacity and heat stability of curcumin increased as the PC content of the lecithin increased. These results showed that commercial plant-based lecithins may be suitable for overcoming some of the hurdles normally associated with using liposomes in the food industry, such as high cost and poor stability.


Assuntos
Curcumina/química , Helianthus/química , Lecitinas/química , Extratos Vegetais/química , Curcumina/farmacologia , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Lipossomos/química , Fosfatidilcolinas/análise
17.
Food Res Int ; 108: 246-253, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29735054

RESUMO

The present work evaluated the feasibility of different pluronics (F127, F87 and P85) utilized as modifiers to improve the stability and bioaccessibility of curcumin liposomes (cur-Lps). Pluronics modified curcumin liposomes (cur-pluronic-Lps) were prepared by thin film evaporation combined with dynamic high pressure microfluidization. The particle size and polydispersity index of cur-pluronic-Lps was significantly lower than cur-Lps. Fourier transform infrared spectroscopy analysis revealed that curcumin was loaded in liposomes successfully and X-ray diffraction suggested that curcumin in the liposomes was in an amorphous state. In vitro release studies demonstrated that 73.4%, 63.9%, 66.7% and 58.9% curcumin released from cur-Lps, cur-F127-Lps, cur-F87-Lps and cur-P85-Lps, respectively. Compared with cur-Lps, cur-pluronic-Lps showed a slower release rate and lower cumulative release percentage for curcumin. Non-Fickian transport was the main release mechanism for cur-Lps, cur-F127-Lps and cur-F87-Lps, and typically the first-order model fitted cur-P85-Lps release. Stability studies (exposure to solutions of different pH and heat treatment) indicated that pluronics modification could enhance their pH stability and thermal stability. In vitro simulated gastrointestinal tract studies suggested that pluronics modification could significantly improve the absorption of cur-Lps. Bioaccessibility of curcumin liposomes increased in the following order: cur-Lps < cur-F87-Lps < cur-P85-Lps < cur-F127-Lps. These results may guide the potential application of pluronics modified liposomes as carriers of curcumin in nutraceutical and functional foods.


Assuntos
Curcumina/química , Suplementos Nutricionais , Digestão , Alimento Funcional , Lipídeos/química , Poloxâmero/química , Disponibilidade Biológica , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Estudos de Viabilidade , Suco Gástrico/química , Absorção Gastrointestinal , Concentração de Íons de Hidrogênio , Secreções Intestinais/química , Cinética , Lipossomos , Tamanho da Partícula , Solubilidade
18.
J Agric Food Chem ; 55(25): 10086-92, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18001030

RESUMO

Tricin (5,7,4'-trihydroxy-3',5'-dimethoxyflavone) occurs in its glycosidic form in rice bran and other grass species such as wheat, barley, and maize. Tricin is considered sufficiently safe for clinical development as a cancer chemopreventive agent, therefore it can be used for cancer prevention. This study established a new method for the preparation of tricin from bamboo leaves as an alternative to traditional methods such as chemical synthesis via the Baker-Venkata-Raman reaction between acetylsyringic acid and phloroacetophenone. Tricin was prepared from an antioxidant product that was derived from bamboo leaves (AOB) by extraction with aqueous ethanol. A concentrated solution of this product was obtained and then processed by polystyrene (AB-8) resin column chromatography and preparative high-performance liquid chromatography (HPLC) with 30% (v/v) acetonitrile in 1% (v/v) acetic acid as the mobile phase. The collected tricin-rich fraction was further sequentially purified by dialysis membrane separation and drowning-out crystallization methods. The purity was assessed by analytical HPLC with 25% (v/v) acetonitrile in 1% (v/v) acetic acid as the mobile phase, and the chemical confirmation was evaluated by infrared, mass, nuclear magnetic resonance, and ultraviolet spectroscopies. Tricin (3.09 g) was prepared from 174 g of a crude column chromatography fraction obtained from 5 L of AOB concentrated solution. The present method is appropriate for preparing quantities of pure tricin, which can be used for the quantification of tricin in various plant herbs and further for pharmaceutical/biomedical applications and evaluation.


Assuntos
Antioxidantes/química , Flavonoides/isolamento & purificação , Folhas de Planta/química , Poaceae/química , Anticarcinógenos , Cromatografia , Cromatografia Líquida de Alta Pressão , Flavonoides/síntese química , Poliestirenos
19.
J Chromatogr A ; 1530: 226-231, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29146428

RESUMO

Polyethylene glycol (PEG) was further applied for fractionating dextrin prepared from cassava starch. The initial dextrin concentration and pH of the dextrin solutions were crucially considered in this study with the average molecular-weight dispersity (DMa) as the index. The results showed that the initial dextrin concentration significantly affected the mass fraction and the molecular weight distribution of each dextrin fraction obtained from gradient PEG precipitation. However, the initial dextrin concentration, which ranged from 0.9% to 3.6%, did not affect the DMa of the dextrin fractions. Furthermore, the DMa of the fractions obtained at pHs 4.00, 4.96, 6.00, 6.92, 7.99, 8.96, and 9.91, was 1.364, 1.341, 1.305, 1.286, 1.273, 1.311, and 1.404, respectively, while the dispersity of the parent dextrin was 2.052. These results suggest that the preparative approach, gradient PEG precipitation, is applicable in acidic, neutral, and alkaline environments, and that a weakly alkaline environment is optimal for dextrin fractionation.


Assuntos
Fracionamento Químico , Dextrinas/química , Dextrinas/isolamento & purificação , Polietilenoglicóis/química , Dextrinas/análise , Concentração de Íons de Hidrogênio , Manihot/química , Peso Molecular
20.
Carbohydr Polym ; 156: 322-332, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-27842829

RESUMO

Hybrid liposomes, composed of amphiphilic chitosan and phospholipid, were prepared and used to evaluate the effect of amphiphilic polymers on the properties of liposomes. Successful preparation of the hybrid liposomes was confirmed using physicochemical characteristics, including morphology, particle size and zeta potential. Physical stability studies (exposure to solutions of increasing ionic strength and heat treatment) indicated that the hybrid liposomes had better ionic stability than amphiphilic chitosan-based polymeric liposomes and higher thermal stability than traditional phospholipid liposomes. Curcumin was then encapsulated in the hybrid liposomes. Compared with phospholipid liposomes, the hybrid liposomes displayed better storage stability and more sustained curcumin release. Cellular uptake experiments showed that the hybrid liposomes significantly increased the bioavailability of curcumin. The study highlights the potential of well-designed stable hybrid liposomes that increase the stability and bioavailability of lipophilic bioactive, such as curcumin.


Assuntos
Quitosana/química , Curcumina/química , Portadores de Fármacos/síntese química , Lipossomos/síntese química , Fosfolipídeos/química , Disponibilidade Biológica , Portadores de Fármacos/química , Lipossomos/química , Tamanho da Partícula
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