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1.
Food Chem ; 351: 129356, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33647693

RESUMO

Nanoemulsions are currently of interest in the functional food sector because their small droplet size (100-500 nm) provides a number of potential advantages over conventional emulsions. This study concerned the behavior of nanoemulsions stabilized with whey proteins and two synthetic emulsifiers (Tween 80 and Croduret), and exposed to conditions simulating the human upper gastrointestinal tract. In particular, the effect of synthetic emulsifiers (food additives) on the interfacial composition and digestion rate of milk proteins at the interface of nanoemulsions was determined. The results indicate that the protein was partially co-absorbed with only one synthetic emulsifier (Croduret) at the interface, which made protein more resistant to digestion in the nanoemulsion system. This suggests that the degree of protein digestion can be controlled by appropriate selection of synthetic emulsifiers and presenting the protein in nanoemulsion system.


Assuntos
Emulsificantes/química , Nanoestruturas/química , Proteólise , Proteínas do Soro do Leite/química , Humanos , Tamanho da Partícula , Polissorbatos/química
2.
Carbohydr Polym ; 260: 117824, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712165

RESUMO

Rhamnogalacturonan I (RG-I) enriched pectic polysaccharides were extracted from Cerasus humilis fruits (RPCF, RG-I: 74.46 %). Structural characterization including FTIR, XRD, NMR, HPAEC and SEM demonstrated that RPCF was a high-methoxy acetylated pectin macromolecule with abundant arabinose and galactose side chains (DM: 53.41 %, MW: 1098 kDa, (Ara + Gal)/Rha: 5.37 %). RPCF afforded additional lipid oxidation stability for emulsions, and exhibited significantly better emulsification performance than citrus pectin. In addition, RPCF formed a weak gel network that stabilized the emulsions (G' > G″). Interestingly, RPCF had behaviors that are divergent from those of commercial high-methoxy pectin because it demonstrated potential in forming sugar-free gels systems. Overall, Cerasus humilis is a new source of pectin rich in RG-I. RPCF can be used as a novel emulsifier with gelling and antioxidant effects, providing its alternative application as a natural emulsifier and rheological modifier in a wide range of products, including those with oil-in-water and low sugar.


Assuntos
Pectinas/química , Polissacarídeos/química , Prunus/metabolismo , Antioxidantes/química , Emulsificantes/química , Emulsões/química , Peso Molecular , Pectinas/análise , Pectinas/metabolismo , Polissacarídeos/análise , Polissacarídeos/metabolismo , Reologia
3.
Carbohydr Polym ; 260: 117711, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712120

RESUMO

The metabolites produced by plants can be enhanced by plant tissue culture. In Premma puberula Pamp., the pectin content in leaves is 30 %-40 %, and it is widely used in the food industry and medicine. However, inefficient propagation has seriously restricted the utilization of pectin resources. Therefore, we established an efficient micropropagation technology for P. puberula through comparative analysis in mature leaves of regenerated and conventionally propagated plants. The results showed that the pectin composition of their leaves was similar in terms of galacturonic acid, monosaccharide composition, degree of esterification, functional groups, nuclear magnetic resonance spectrum and morphological characteristics. Furthermore, micropropagated plants had better hardness, gumminess and chewiness characteristics than conventionally propagated plants and were similar in emulsion stability, adhesiveness, springiness, cohesiveness and viscoelasticity. Therefore, micropropagation technology will provide an important guarantee for the industrial production of pectin from P. puberula. The technical essentials include callus induction, embryoid formation, and root induction, followed by acclimatization and transplanting.


Assuntos
Lamiaceae/metabolismo , Pectinas/metabolismo , Emulsificantes/química , Esterificação , Ácidos Hexurônicos/análise , Lamiaceae/citologia , Monossacarídeos/análise , Pectinas/química , Pectinas/isolamento & purificação , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Viscosidade
4.
Food Chem ; 352: 129358, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33657484

RESUMO

A novel maltoheptaose-palmitate ester (G7-PA) was synthesized and investigated for emulsion properties. First of all, the optimal conditions for lipase-catalyzed G7-PA synthesis, which were 0.2 of the G7/PA molar ratio, 33.5 U of immobilized CALB per 1 g of PA in 10% DMSO, were determined by response surface methodology. G7-PA was compared with the commercial sucrose-PA (S-PA) in terms of emulsion-forming ability and stability at extreme conditions. At the 0.1% surfactant concentration, G7-PA emulsion exhibited a droplet distribution similar to the 0.2% surfactant condition, while S-PA emulsion was quickly destabilized. G7-PA showed better emulsifying properties than the S-PA at the acidic condition (pH 3). Flocculation and phase separation was observed at the S-PA emulsion, but the G7-PA emulsion was stable for 7-day. In thermostability tests, G7-PA and S-PA both were stable up to the boiling temperature. Conclusively, G7-PA exhibits excellent properties as a biosurfactant in O/W emulsion compared with S-PA.


Assuntos
Biocatálise , Emulsificantes/química , Emulsificantes/síntese química , Ésteres/química , Glucanos/química , Glucanos/síntese química , Lipase/metabolismo , Técnicas de Química Sintética
5.
Food Chem ; 350: 129271, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33618095

RESUMO

In this study, the structural, interfacial, and emulsifying properties of high-intensity ultrasound (HUS)-treated pea protein isolate (PPIUS) were investigated. HUS at 50% amplitude and 57-60 W·cm-2 for 5 min markedly improved protein solubility (by 132%), surface hydrophobicity (by 173%), and reduced particle size (by 52%). These physicochemical changes in PPIUS led to more rapid protein adsorption at the oil-water interface, improved emulsifying activity (by 18-27%) and capacity (by 11%), and enhanced emulsion physical stability. The multilayer nature, albeit less elastic, of the interfacial membrane formed by PPIUS when compared to control protein (PPIC), based on dilatational testing, contributed to the above results. Moreover, PPIUS-stabilized emulsions exhibited a tendency of being less susceptible to lipid oxidation during storage. Thus, structure-modifying HUS may be a valuable processing technology for the manufacture of pea protein-based emulsion foods.


Assuntos
Emulsificantes/química , Manipulação de Alimentos/métodos , Proteínas de Ervilha/química , Ondas Ultrassônicas , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Oxirredução , Tamanho da Partícula , Solubilidade
6.
Food Chem ; 349: 129203, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33581433

RESUMO

Fabrication of food-grade water-in-oil (W/O) emulsions without surfactant, as the primary substitutes of trans-fat and saturated fat, was still a significant challenge in food science. A facial method has been adopted to fabricate W/O emulsions at 20 °C. The obtained emulsion had long-time stability, and there was no apparent phase separation or oiling-out after 60 days of storage. In this system, beeswax served as a stabilizer for both oleogels and oleogel-based emulsions. The sol-gel melting temperature of the oleogel was 37 ± 0.5 °C by regulating beeswax content to 4% w/w, and then the oleogel was used to fabricate W/O emulsion with the droplet diameter of around 9 µm. Thermo-reversible and thixotropic properties of oleogels were both retained for emulsions. Furthermore, both oleogels and oleogel-based emulsions had compact gel-like structures. The self-emulsifying W/O emulsions without surfactant would have great potential applications in food industry, pharmaceutical industry and feed industry.


Assuntos
Emulsificantes/química , Óleos/química , Temperatura , Água/química , Ceras/química , Emulsões , Compostos Orgânicos/química , Tensoativos/química
7.
Food Chem ; 348: 129148, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33515946

RESUMO

The potency of oil-soluble vitamins (vitamins A, D, E and K) in fortified foods can be improved by understanding how food matrices impact their bioavailability. In this review, the major food matrix effects influencing the bioavailability of oil-soluble vitamins are highlighted: oil content, oil composition, particle size, interfacial properties, and food additives. Droplet size and aggregation state in the human gut impact vitamin bioavailability by modulating lipid digestion, vitamin release, and vitamin solubilization. Vitamins in small isolated oil droplets typically have a higher bioavailability than those in large or aggregated ones. Emulsifiers, stabilizers, or texture modifiers can therefore affect bioavailability by influencing droplet size or aggregation. The dimensions of the hydrophobic domains in mixed micelles depends on lipid type: if the domains are too small, vitamin bioavailability is low. Overall, this review highlights the importance of carefully designing food matrices to improve vitamin bioavailability.


Assuntos
Óleos/química , Vitaminas/química , Disponibilidade Biológica , Digestão , Emulsificantes/química , Humanos , Micelas , Solubilidade , Vitaminas/farmacocinética
8.
Carbohydr Polym ; 256: 117523, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483044

RESUMO

EPS-BMS, is to our knowledge, the first high molecular weight exopolysaccharide from potential probiotic Leuconostoc citreum-BMS strain that consists on a mixture of α-(1,6)-dextran branched at the third position and ß-(2,6)-levan. This sample exhibited interesting rheological and emulsifying properties under different conditions. Steady shear experiments proved that EPS-BMS had a pseudoplastic behavior without thixotropic properties. Interestingly, pseudoplasticity was maintained even under stress conditions of temperature, pH and salts, which could provide some sensory properties for food products such as mouth feel. Dynamic oscillatory measurements reflected a liquid-like behavior of the sample regardless of the studied EPS concentration, pH, temperature and ionic force. Results related to the emulsifying as well as interfacial properties showed that EPS-BMS had great potential to be applied as emulsifier and/or emulsion stabilizer in both neutral and acidic conditions. Based on the properties reported in this work, EPS-BMS could be potentially applied in the food industry.


Assuntos
Dextranos/química , Emulsificantes/química , Frutanos/química , Leuconostoc/química , Polissacarídeos Bacterianos/química , Probióticos/química , Culinária/métodos , Dextranos/isolamento & purificação , Emulsificantes/isolamento & purificação , Frutanos/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Leuconostoc/metabolismo , Polissacarídeos Bacterianos/isolamento & purificação , Probióticos/metabolismo , Reologia , Sais/química , Percepção Gustatória/fisiologia , Temperatura
9.
Food Chem ; 346: 128848, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33387831

RESUMO

The effects of 2 wt% emulsifier and crystalline sugar on the isothermal solidification and polymorphic behavior of cocoa butter were evaluated. The emulsifiers investigated were commercial soy lecithin, polyglycerol polyricinoleate (PGPR), citric acid esters of mono- and diacylglycerols (CITREM) and ammonium phosphatides (AP). All emulsifiers accelerated cocoa butter nucleation and growth from the melt, with PGPR showing the smallest enhancement. Lecithin and AP minimally affected the polymorphic form IV-to-V transition contrary to PGPR and CITREM, whichboth promoted the formation of form V crystals. The presence of sugar alone accelerated cocoa butter solidification while limiting the ability of the emulsifiers to do so. Sugar alone, and in the presence of emulsifier, hindered the polymorphic form IV-to-V transition. This study shows that the effects of emulsifiers on the isothermal crystallization of cocoa butter can be muted in the presence of crystalline sugar, suggesting a complex interplay dependent on emulsifier molecular structure.


Assuntos
Cristalização , Gorduras na Dieta/análise , Emulsificantes/química , Açúcares/química
10.
Food Chem ; 346: 128903, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33429299

RESUMO

Phosvitin (PSV) is considered as a good emulsifier, although it has a low proportion of hydrophobic regions and steric hindrance. Wheat gluten (WG) possesses excellent hydrophobicity and macromolecular network structure. In this work, WG was subjected to a series of Na2SO3 solution, followed by cross-linking with PSV under transglutaminase (TGase) catalyzation. The results showed that Na2SO3 could break disulfide bonds of WG and increase its solubility from 7.33% to 42.82% with 1200 mg/L of Na2SO3. Correspondingly, the cross-linking degree was significantly enhanced. Compared to PSV, the cross-linked PSV-WG exhibited a higher surface hydrophobicity and thermal stability, with a lower zeta potential and apparent viscosity. The emulsifying activity of PSV-WG reached 17.42, 20.63 and 20.28 m2/g with Na2SO3 concentration of 300, 600 and 900 mg/L, which were all higher than that of PSV (15.19 m2/g). This work provided a novel strategy to elevate emulsifying properties of PSV by cross-link reaction.


Assuntos
Glutens/metabolismo , Fosvitina/metabolismo , Sulfatos/química , Transglutaminases/metabolismo , Biocatálise , Dissulfetos/química , Emulsificantes/química , Glutens/química , Interações Hidrofóbicas e Hidrofílicas , Peso Molecular , Fosvitina/química , Solubilidade , Temperatura , Triticum/metabolismo , Viscosidade
11.
Carbohydr Polym ; 255: 117334, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436177

RESUMO

Development of new sources and isolation processes has recently enhanced the production of cellulose in many different colloidal states. Even though cellulose is widely used as a functional ingredient in the food industry, the relationship between the colloidal states of cellulose and its applications is mostly unknown. This review covers the recent progress on illustrating various colloidal states of cellulose and the influencing factors with special emphasis on the correlation between the colloidal states of cellulose and its applications in food industry. The associated unique colloidal states of cellulose like high aspect ratio, crystalline structure, surface charge, and wettability not only promote the stability of colloidal systems, but also help improve the nutritional aspects of cellulose by facilitating its interactions with digestive system. Further studies are required for the rational control and improvement of the colloidal states of cellulose and producing food systems with enhanced functional and nutritional properties.


Assuntos
Celulose/análogos & derivados , Emulsificantes/química , Tecnologia de Alimentos/métodos , Nanofibras/química , Nanopartículas/química , Coloides , Humanos , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Eletricidade Estática , Molhabilidade
12.
Food Chem ; 339: 128053, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32947105

RESUMO

A biopolymer-polyphenol conjugate-stabilized oil-in-water emulsion system was established to improve the chemical stability and bioaccessibility of ß-carotene (BC). In this study, the emulsifying properties and contribution of a ferulic acid-grafted curdlan conjugate (Cur-D-g-FA) to the chemical stability of BC were investigated. Results showed that the emulsification ability of emulsions stabilized by Cur-D-g-FA remarkably increased with an increasing concentration from 0.05% to 0.8% (w/v) along with decreasing average droplet sizes, negatively charged zeta potentials, and uniform size distributions. The emulsions stabilized by 0.8% Cur-D-g-FA exhibited pronounced shear thinning and solid-like elastic properties as well as satisfactory oxidation stability. The emulsions stabilized by 0.8% Cur-D-g-FA had excellent ability to improve the chemical stability of BC when exposed to different environmental stresses and resulted in the favorable bioaccessibility of BC in vitro. The results prove that Cur-D-g-FA as a promising stabilizer has great potential to protect liposoluble nutrients in food-grade emulsion-delivery systems.


Assuntos
Ácidos Cumáricos/química , Emulsificantes/química , beta Caroteno/química , beta-Glucanas/química , Disponibilidade Biológica , Óleo de Milho/química , Emulsões/química , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Concentração Osmolar , Oxirredução , beta Caroteno/farmacocinética
13.
Food Chem ; 345: 128542, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33321349

RESUMO

The seed of Stauntonia brachyanthera is usually regarded as waste after fructus processing. Here, the potential utilization value of the protein isolate (SSPI) from seeds was evaluated by investigating its physicochemical and functional properties. SSPI was a complex protein containing 7 distinct subunits that had high contents of most essential amino acids. The maximum foaming capacity of SSPI was 406.7 ± 41% at pH 9.0, and the water holding/oil adsorption capacities were 4.66 g/g and 9.06 g/g, respectively. SSPI aggregates with a particle size of 154.1 ± 5.2 nm was prepared after heat treatment, which was performed as a Pickering-like stabilizer for the structuring of water-in-oil-in-water emulsions. The outer droplet size of emulsions decreased as the aggregate concentration increased. Emulsion gels could be observed with the increasing aggregate concentration and oil fraction. Further study found that the stabilities of inner water-in-oil droplets and creaming were progressively increased by increasing the aggregate concentration during storage.


Assuntos
Emulsificantes/química , Emulsificantes/isolamento & purificação , Temperatura Alta , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Ranunculales/química , Sementes/química , Adsorção , Tamanho da Partícula , Água/química
14.
Food Chem ; 337: 127949, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919267

RESUMO

This study compared the interfacial and emulsifying properties of purified saponins and non-purified saponin-rich extracts of Glycyrrhiza glabra, and highlighted potential mechanisms by which crude surface-active compositions, such as liquorice root extract (LRE), act as emulsifiers. LRE presented different fluid properties, in comparison to purified glycyrrhizin (PG), at equivalent glycyrrhizin concentrations. Particularly, it exhibited limited glycyrrhizin fibrilization at pH < pKa and efficiently reduced the interfacial tension at the soybean oil/water interface, independently of pH. LRE also presented better emulsification properties, in comparison to PG samples. Emulsions prepared using LRE had lower droplet sizes when using higher oil mass fractions or lower homogenization pressures, which was attributed to 2 main factors: (i) efficient adsorption of glycyrrhizin molecules at relatively low interfacial curvatures, thus accelerating oil phase breakup during homogenization and (ii) sufficient coverage of newly generated droplets due to adsorption of residual surface-active components (e.g. proteins), thus minimizing droplet coalescence.


Assuntos
Emulsificantes/química , Ácido Glicirrízico/química , Extratos Vegetais/química , Emulsões/química , Glycyrrhiza/química , Saponinas/química , Óleo de Soja/química , Tensão Superficial , Água/química
15.
Food Chem ; 334: 127613, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711281

RESUMO

The optimization of ultrasound-assisted alkaline extraction and enzymatic deamidation by protein-glutaminase (PG) on evening primrose seed cake (EPSC) protein and its effect on structure (amino acid composition, secondary structure and electrophoresis pattern) and techno-functional properties (water-holding and oil-binding capacities, solubility, emulsifying and foaming properties) of EPSC protein were evaluated. The optimum conditions of the both processes were measured using response surface methodology (RSM). The maximum yield (26.4%) and protein content (86.1%) were reached at the optimized extraction conditions. Optimal conditions of PG deamidation based on reaching a high degree of deamidation (DD) with a simultaneously low degree of hydrolysis (DH). Under these conditions, DD and DH were 39.40 and 2.11%, respectively. Ultrasound-assisted alkaline extraction and enzymatic deamidation by PG have great potential to produce edible EPSC protein with modified techno-functional characteristics that can be used for several aims in the food and pharmaceutical applications.


Assuntos
Fracionamento Químico/métodos , Oenothera biennis/química , Proteínas de Vegetais Comestíveis/química , Amidas/química , Aminoácidos/análise , Emulsificantes/química , Glutaminase/química , Hidrólise , Extratos Vegetais/química , Óleos Vegetais/química , Proteínas de Vegetais Comestíveis/isolamento & purificação , Estrutura Secundária de Proteína , Solubilidade , Ultrassom
16.
Food Chem ; 337: 127989, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920272

RESUMO

In this research, the impact of High Pressure Carbon Dioxide (HPCD) on the physicochemical, interfacial and rheological properties of liquid whole egg (LWE) was investigated. HPCD treatment increased the solubility, free sulfhydryl groups and surface hydrophobicity of LWE. The highest foaming ability (186%) and foaming stability (72%) were obtained at 60 min of HPCD treatment, which were 1.3-fold and 1.4-fold those of the control group (147% and 51%, respectively). Compared with the control group, the LWE emulsion had a minimum particle size (16.3 µm) when the treatment time was 75 min, and the highest absolute value of zeta potential reached 7.66 mV when the processing time was 60 min. HPCD treatment decreased the apparent viscosity of LWE at a low shear rate. Dynamic viscoelastic characteristics indicated that both the G' and G'' moduli of LWE under the HPCD process were lower than those of the control group at any frequency.


Assuntos
Dióxido de Carbono/química , Ovos , Animais , Fenômenos Químicos , Galinhas , Emulsificantes/química , Indústria de Processamento de Alimentos/métodos , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Pressão , Reologia , Solubilidade , Viscosidade
17.
Food Chem ; 339: 128064, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950902

RESUMO

Ultrasonic degradation has become a fascinating strategy for preparing modified pectin, contributing to the improvement of pectin's functional characteristics. In this study, the impacts of structural and conformational characteristics of original and ultrasound-treated citrus pectins on their functional properties were examined. The results showed that compared with ultrasound-treated pectins, untreated pectin presented higher rheological and gelling properties primarily attributed to its larger weight-average molecular weight (Mw), degree of methoxylation, amount of neutral sugar side chains, and z-average radius of gyration, as well as the more extended flexible-chain conformation. However, the ultrasound-treated pectins had better emulsifying properties than untreated pectin in an oil-in-water emulsion system. These properties, visually suggested by morphology analysis, including enhanced emulsifying capacity, emulsifying stability, reduced mean droplet size and negatively charged zeta potential. Moreover, the Mw and chain conformation of untreated and ultrasound-treated pectins played more decisive roles in their functional properties than the others.


Assuntos
Emulsificantes/química , Pectinas/química , Configuração de Carboidratos , Conformação Molecular , Peso Molecular , Monossacarídeos/análise , Reologia , Açúcares , Ultrassom
18.
Food Chem ; 339: 128103, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152885

RESUMO

This study investigates the characterization and emulsifying properties of different type lecithins. Emulsifying properties of lecithins isolated from rainbow trout egg (RL) and trout processing discard (WL) were compared with the soybean (SL) and hen egg yolk (HL) lecithin in sunflower-fish oil O/W emulsion systems. The phospholipid contents of RL and WL were significantly higher than those of HL and SL. The higher phospholipid contents in RL and WL resulted in lower droplet size (18.3-20.5 µm), higher viscosity (2.37-2.51 mPa.s) and higher physical stability (78.11-75.33) of emulsions. The linoleic acid (C18:2) was the most abundant PUFA in terrestrial origin lecithins (HL and SL), whereas DHA and EPA, a valuable omega-3 fatty acid, were the major PUFAs in aquatic origin lecithins (RL and WL). RL and WL formed more stable emulsions than HL and SL. This study provides valuable information for utilization of RL and HL as emulsifier in emulsion systems.


Assuntos
Emulsificantes/química , Lecitinas/química , Lecitinas/isolamento & purificação , Oncorhynchus mykiss , Animais , Galinhas , Ovos , Emulsificantes/isolamento & purificação , Emulsões/química , Ácidos Graxos Insaturados/análise , Feminino , Armazenamento de Alimentos , Indústria de Processamento de Alimentos , Fosfolipídeos/análise , Fosfolipídeos/química , Reologia , Óleo de Girassol/química , Viscosidade
19.
Carbohydr Polym ; 254: 117445, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357915

RESUMO

Nanocellulose are promising Pickering emulsion stabilizers for being sustainable and non-toxic. In this work, semicrystalline cellulose oligomers (SCCO), which were synthesized from maltodextrin using cellobiose as primer by in vitro enzymatic biosystem, were exploited as stabilizers for oil-in-water Pickering emulsions. At first, the morphology, structure, thermal and rheological properties of SCCO suspensions were characterized, showing that SCCO had a sheet morphology and typical cellulose-Ⅱ structure with 56 % crystallinity. Then the kinetic stabilities of emulsions containing various amounts of SCCO were evaluated against external stress such as pH, ionic strength, and temperature. Noting that SCCO-Pickering emulsions exhibited excellent stabilities against changes in centrifugation, pH, ionic strengths, and temperatures, and it was also kinetically stable for up to 6 months. Both SCCO suspensions and their emulsions exhibited gel-like structures and shear-thinning behaviors. These results demonstrated great potential of SCCO to be applied as nanocellulosic emulsifiers in food, cosmetic and pharmaceutical industries.


Assuntos
Celobiose/química , Celulose/química , Emulsificantes/química , Polissacarídeos/química , Celulose/ultraestrutura , Cosméticos/química , Cristalização , Emulsões , Tecnologia de Alimentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Concentração Osmolar , Temperatura , Água/química
20.
Int J Nanomedicine ; 15: 10371-10384, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33376326

RESUMO

Purpose: Many exopolysaccharides (EPS) have significant emulsifying activity. Some EPS produced by the marine bacterial strain FYS have stronger emulsifying activity in the form of nanoparticles, suggesting that they could potentially form Pickering emulsions. We prepared novel EPS/CT Pickering nanoemulsions (ECPN) with EPS as emulsifiers and assessed their ability to ameliorate the poor permeability of calcipotriol (CT) in skin affected by psoriasis vulgaris. Methods: A strain of marine bacterium FYS was identified. Molecular weight, monosaccharide composition and microstructure of EPS were determined by gel permeation chromatography, high-performance liquid chromatography and scanning electron microscopy. EPS nanoparticles were prepared by adjusting the pH, and the emulsifying activity was studied at different pH. ECPN were prepared by ultrasound and optimized by the response surface method. The size distribution, microstructure, stability and in vitro drug release of ECPN were studied. The therapeutic effect of ECPN on psoriasis vulgaris was explored by animal experiments and characterizing histomorphology in vivo. Results: A phylogenetic tree revealed that FYS was a Bacillus halodurans strain. EPS produced by the strain were heteropolysaccharides with a three-dimensional network composed of glucose, galactose, glucuronic acid, rhamnose, galacturonic acid and mannose (32.0:34.3:9.7:7.4:10.3:6.3). The EPS can form nanoparticles at pH = 4-6 with enhanced emulsifying ability. Transmission electron microscopy revealed that EPS nanoparticles adhered to the surface of oil droplets to stabilize the emulsions via a Pickering emulsification mechanism. The prepared ECPN have high stability with a sustained-release effect. Finally, animal experiments showed that ECPN effectively shortened the treatment course of psoriasis vulgaris. Conclusion: EPS is highly possible to have the potential Pickering emulsification mechanism. The stability of the nanoemulsion was high. ECPN also showed potential for use in the treatment of psoriasis vulgaris. This study provides new insight into the medical applications of EPS and the treatment of psoriasis.


Assuntos
Calcitriol/análogos & derivados , Emulsões/química , Polissacarídeos Bacterianos/química , Psoríase/tratamento farmacológico , Animais , Bacillus/química , Bacillus/genética , Calcitriol/administração & dosagem , Calcitriol/farmacologia , Fármacos Dermatológicos/administração & dosagem , Fármacos Dermatológicos/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Emulsificantes/química , Emulsões/administração & dosagem , Concentração de Íons de Hidrogênio , Camundongos , Peso Molecular , Nanopartículas/química , Filogenia , Psoríase/patologia , Pele/efeitos dos fármacos , Pele/patologia
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