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1.
Int J Biol Macromol ; 224: 544-555, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36273549

RESUMO

In this study, we firstly developed an antioxidant and pH-sensitive film based on arrowhead starch (AS), κ-carrageenan (KC) and black chokeberry extract (BCE) and its physical and structural properties were investigated. We found BCE showed different colors in different pH solutions and incorporation with KC and BCE could significantly decrease light transmittance, increase thickness, elongation at break and pH-sensitive property of AS film. The results of structural property assay indicated that there were some intermolecular interactions between BCE and AS/KC in AS-KC-BCE films. Secondly, we investigated the rheological property of AS, AS-KC and AS-KC-BCE suspensions and found the suspensions showed an obvious shear-thinning behavior with high apparent viscosity. Finally, the functional properties of AS-KC-BCE films were investigated and AS-KC-BCE films showed strong scavenging activity on DPPH free radical and presented visible colour changes in response to the changes of the chicken wing qualities. The results suggest that AS-KC-BCE films can be used in active and intelligent packaging of food industry.


Assuntos
Antioxidantes , Conservação de Alimentos , Animais , Antioxidantes/química , Carragenina/química , Galinhas , Photinia , Sagittaria/química , Amido/química , Extratos Vegetais/química , Concentração de Íons de Hidrogênio , Conservação de Alimentos/métodos
2.
Food Chem ; 217: 461-468, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27664659

RESUMO

An efficient decoloration method for polysaccharides from the sprouts of Toona sinensis (A. Juss.) Roem (PSTS) by anion exchange macroporous resins (AEMR) was investigated in the present paper. The results suggested that D941 resin offered better decoloration efficiency than other tested resins. Based on single-factor experiments, the optimal decoloration parameters of D941 resin were obtained as follows: temperature of 45°C, sample initial concentration of 30mg/ml, pH value of 8.5, static decoloration time of 90min, dynamic decoloration processing volume of 5.5BV with the flow rate of 2BV/h. Decoloration ratio, PSTS recovery ratio and selectivity coefficient were 91.94±1.23%, 90.05±2.35% and 10.92±0.63, respectively. Most of pigment impurities were successfully removed from PSTS solutions after treated by D941 resin, and there was no significant difference in carbohydrate concentration, characteristic groups and molecular weight. Compared with H2O2 oxidation and activated carbon adsorption, this developed method is superior.


Assuntos
Resinas de Troca Aniônica/química , Meliaceae , Pigmentos Biológicos/análise , Extratos Vegetais/análise , Polissacarídeos/análise , Plântula/química , Adsorção
3.
Chem Commun (Camb) ; 52(89): 13105-13108, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27759142

RESUMO

A visible-light-induced radical-triggered chemoselective domino process to access α,α-di-functionalized ketones under mild conditions has been developed. This protocol provides a direct approach to synthesize α-chloro or α-alkoxy aryl ketones based on the electronic properties of the substrates. The reaction can tolerate a variety of functional groups to afford the corresponding products in moderate to good yields.

4.
Int J Biol Macromol ; 78: 324-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25891913

RESUMO

In the present study, characterization and cardioprotective activities in vivo of a novel purified polysaccharide (PECGp) from Endothelium corneum gigeriae Galli were investigated. The results found that PECGp had a 96 kDa molecular weight. The backbone chains were composed of α-D-Glc and α-L-Rha linked by (1→4) glycosidic bonds. (1→4, 6) linked α-D-Glc and (1→2, 4) linked α-L-Rha in backbone chains with branches consisting of (1→4) linked α-D-Glc and terminal α-D-Glc-6-COOH. The assay of cardioprotective activities demonstrated that PECGp could significantly reduce the ST-segment elevation, prevented abnormal changes of heart muscle morphology, reverse abnormal hemodynamic and hemorheological parameters, rectify disorganized superoxide dismutase, nitric oxide synthase, nitric oxide, malondialdehyde, creatine kinase, creatine kinase MB fraction and lactate dehydrogenase levels. The results suggested that PECGp could be considered as a potential candidate for developing novel cardioprotective agents.


Assuntos
Cardiotônicos/química , Cardiotônicos/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Creatina Quinase/sangue , Creatina Quinase/metabolismo , Creatina Quinase Forma MB/sangue , Eletrocardiografia/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Hemorreologia , L-Lactato Desidrogenase/sangue , Masculino , Malondialdeído/sangue , Malondialdeído/metabolismo , Infarto do Miocárdio/sangue , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Ratos , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo
5.
Food Chem ; 179: 15-25, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25722134

RESUMO

In this paper, an economical and efficient technology for the extraction of resveratrol from peanut sprouts by multi-stage countercurrent extraction (MSCE) was investigated based on the alkaline extraction and acid precipitation method (AEAP). Firstly, the MSCE equipment and operation procedures were designed. Then, the optimal parameters of MSCE were obtained by using single-factor experiments and Box-Behnken design (BBD) as follows: extraction temperature of 46.6 °C, CaO to raw material ratio of 6:100, water to raw material ratio of 8.8:1 and extraction time of 51.7 min. Finally, the performance of MSCE was compared against the single pot extraction (SPE) under optimal conditions. The results demonstrated that MSCE was a time-saving, energy-saving, and cost-saving extraction technology for manufacturing resveratrol from peanut sprouts.


Assuntos
Arachis/química , Distribuição Contracorrente/métodos , Estilbenos/isolamento & purificação , Resveratrol , Extração em Fase Sólida
6.
Carbohydr Polym ; 110: 10-7, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-24906722

RESUMO

In this study, optimization of ultrasound-assisted extraction and antioxidant activity of polysaccharides from the aerial root of Ficus microcarpa (FMPS) were investigated. The optimal conditions for extraction of FMPS were determined as followings: ultrasound power 200 W, ultrasound temperature 70°C, extraction temperature 74°C, liquid-solid ratio 35, extraction time 238 min, ultrasound time 49 min. The experimental yield of FMPS (3.44%) obtained under these conditions was well agreement with the value predicted by the model. In addition, Fourier transform-infrared spectroscopy and antioxidant activity assays revealed that FMPS were acidic polysaccharides and had strong Fe2+ chelating activity and moderate hydrogen peroxide scavenging effect. Further work on the purification, structure characterization and antioxidant activity in vivo of FMPS is in progress.


Assuntos
Antioxidantes/efeitos da radiação , Medicamentos de Ervas Chinesas/efeitos da radiação , Ficus , Raízes de Plantas , Polissacarídeos/efeitos da radiação , Som , Antioxidantes/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Componentes Aéreos da Planta , Polissacarídeos/isolamento & purificação
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