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1.
Food Chem ; 339: 128053, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32947105

RESUMEN

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.


Asunto(s)
Ácidos Cumáricos/química , Emulsionantes/química , beta Caroteno/química , beta-Glucanos/química , Disponibilidad Biológica , Aceite de Maíz/química , Emulsiones/química , Almacenamiento de Alimentos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Oxidación-Reducción , beta Caroteno/farmacocinética
2.
Food Chem ; 339: 128081, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33152874

RESUMEN

In the present study, three-phase partitioning (TPP) coupled with gradient ethanol precipitation (GEP) was developed for the first time to extract and isolate polysaccharides (GPSs) from raw garlic (Allium sativum L.) bulbs. Four kinds of fructose polymers, namely, GPS35, GPS50, GPS65, and GPS80, were obtained at the final ethanol precipitation concentrations of 35%, 50%, 65%, and 80% (v/v), respectively, and their physicochemical characteristics and in vitro biological activities were investigated. Results indicated that GPS80 had higher carbohydrate (86.68% ± 0.90%) and uronic acid (12.89% ± 0.09%) contents, lower weight-average molecular weight (8.93 × 103 Da), and looser surface morphology than the other three GPSs. Furthermore, among the four GPSs, GPS80 exhibited the strongest antioxidant capacities, inhibitory effects on α-amylase and α-glycosidase, and nitric oxide stimulatory activity on RAW264.7 macrophage cells in vitro. Therefore, this study provides a simple and feasible technological strategy for producing bioactive polysaccharides from raw Allium vegetables.


Asunto(s)
Precipitación Química , Etanol/química , Ajo/química , Tallos de la Planta/química , Polisacáridos/química , Polisacáridos/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Fenómenos Químicos , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/farmacología , Peso Molecular , Polisacáridos/aislamiento & purificación , alfa-Amilasas/antagonistas & inhibidores , alfa-Glucosidasas/metabolismo
3.
Food Chem ; 337: 127798, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32799166

RESUMEN

In this study, polysaccharides (BPSs) were obtained from fresh bitter gourd (Momordica charantia L.) by room temperature extraction techniques, including three-phase partitioning (TPP) and ultrasonic-assisted extraction (UAE) performed in different solvents. The results showed that the extraction methods had significant influence on the extraction yield, chemical composition, weight-average molecular weight (Mw), monosaccharide composition, preliminary structural characterization and microstructure of the BPSs. The BPS-W sample obtained from the bitter gourd residue via UAE in distilled water had a higher uronic acid content (24.22%) and possessed stronger antioxidant capacities and α-amylase and α-glycosidase inhibitory activities than BPS-C extracted with UAE in citric acid, BPS-A extracted with UAE in 1.25 mol/L NaOH/0.05% NaBH4, and BPS-J extracted from bitter gourd juice by TPP. Moreover, BPS-A, which had the lowest Mws, showed the best bile acid-binding capacity among the four BPSs. This study had great potentials for the preparation of bioactive polysaccharides from fresh vegetables.


Asunto(s)
Fraccionamiento Químico/métodos , Momordica charantia/química , Polisacáridos/aislamiento & purificación , Antioxidantes/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Temperatura , Ácidos Urónicos/análisis , alfa-Amilasas/antagonistas & inhibidores , alfa-Glucosidasas/efectos de los fármacos
4.
Food Chem ; 320: 126647, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32220708

RESUMEN

In this study, three-phase partitioning (TPP) coupled with gradient ammonium sulfate ((NH4)2SO4) precipitation (GNP) method was first used to extract and separate bioactive polysaccharides (OPSs) from fresh okra pods. Results showed that OPS-50 obtained by GNP at a saturation of 50% (NH4)2SO4 after TPP presented higher precipitation yield, carbohydrate (86.82%) and uronic acid (22.34%) contents with same monosaccharide composition and different molar ratios compared with OPS-30 and OPS-40 obtained via GNP at saturations of 30% and 40% (NH4)2SO4, respectively. OPS-50 had lower weight-average molecular weight (3.65 × 106 g/mol), more flexible chain, and relatively looser surface structure compared with OPS-30, OPS-40, and the OPS obtained with TPP parallelized with decreased apparent viscosity and dynamic viscoelasticity. Furthermore, OPS-50 exhibited stronger DPPH radical-scavenging ability, antioxidant capacity, and α-amylase and α-glucosidase inhibitory activities in vitro than OPS, OPS-30, and OPS-40.


Asunto(s)
Abelmoschus/química , Polisacáridos/química , Antioxidantes/química , Carbohidratos/química , Fenómenos Químicos , Peso Molecular
5.
Chin J Traumatol ; 18(5): 296-301, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26777715

RESUMEN

The bony naso-orbital-ethmoid (NOE) complex is a 3-dimensional delicate anatomic structure. Damages to this region may result in severe facial dysfunction and malformation. The management and optimal surgical treatment strategies of NOE fractures remain controversial. For a patient with NOE trauma, doctors should perform comprehensive clinical examination and radiographic analysis to assess the type and extent of fracture. The results of assessment will assist doctors to make a patientspecific program for the sake of reducing post-operation complications and restoring normal appearance and function as much as possible. This review focuses on the advancement of management of NOE fractures including symptoms, classifications, diagnosis, approaches, treatment and new techniques in this field.


Asunto(s)
Hueso Etmoides/lesiones , Hueso Nasal/lesiones , Fracturas Orbitales/cirugía , Hueso Etmoides/diagnóstico por imagen , Hueso Etmoides/cirugía , Fijación de Fractura , Humanos , Hueso Nasal/diagnóstico por imagen , Hueso Nasal/cirugía , Fracturas Orbitales/diagnóstico por imagen , Complicaciones Posoperatorias/prevención & control , Procedimientos de Cirugía Plástica , Cirugía Asistida por Computador , Tendones/cirugía , Tomografía Computarizada por Rayos X
6.
J Environ Sci (China) ; 18(5): 973-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17278757

RESUMEN

The influence of SO2 on the performance of Ag-Pd/Al2O3 for the selective catalytic reduction (SCR) of NOx with C2H5OH was investigated experimentally. The activity test results suggest that Ag-Pd/Al203 shows a small activity loss in the presence of SO2 when using C2H5OH as a reductant. In situ DRIFTS spectra show that the activity loss originates from the formation of surface sulphate species on the Ag-Pd/Al2O3. The surface sulphate species formation inhibits the formation of nitrate, whereas hardly changes the partial oxidation of C2HsOH. Compared with the NOx reduction by C3H6 an obvious suppression of the surface sulphate species formation was observed by DRIFTS experiment when using C2H50H as a reductant. This phenomenon reveals the better catalytic performance and strong SO2 tolerance of Ag-Pd/Al2O3-C2H5OH system.


Asunto(s)
Óxido de Aluminio/química , Etanol/química , Óxidos de Nitrógeno/química , Paladio/química , Plata/química , Dióxido de Azufre/química , Catálisis , Espectroscopía Infrarroja por Transformada de Fourier
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(2): 204-6, 2005 Feb.
Artículo en Chino | MEDLINE | ID: mdl-15852857

RESUMEN

The reaction process of catalytic combustion of ARB on CuFe2O4 in the presence and absence of O2 was studied by in situ DRIFT spectroscopy. The results showed that the decomposition of the sulfonic group of ARB molecule was not affected by the reaction atmosphere, but the decompositions of azo group and aromatic ring were markedly affected by the presence or absence of O2. The catalytic combustion of ARB was faster in air atmosphere than that in N2 atmosphere, and ARB could be completely oxidized to CO2 and nitrate at 300 degrees C. But in N2 atmosphere, it was very difficult for the decomposition of ARB to complete at 300 degrees C, even though air was introduced following this process. The temperature required for the rapid and complete decomposition would be as high as 500 degrees C.


Asunto(s)
Compuestos Azo/química , Cobre/química , Compuestos Ferrosos/química , Calor , Naftalenosulfonatos/química , Oxígeno/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Dióxido de Carbono/química , Catálisis , Nitratos/química , Nitrógeno/química , Oxidación-Reducción
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