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1.
Int J Biol Macromol ; 264(Pt 2): 130684, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460647

RESUMO

The impact of recrystallization conditions and drying temperatures on the crystallization and digestibility of native waxy maize (Zea mays L.) starch (NWMS) was explored. This study involved subjecting NWMS to concurrent debranching and crystallization at 50 °C for up to 7 days. Samples were collected by oven-drying at 40, 60, and 80 °C for 24 h. This simultaneous debranching and crystallization process increased the resistant starch (RS) content by approximately 48 % compared to the native starch. The drying temperatures significantly influenced the RS content, with samples dried at 60 °C exhibiting the lowest digestibility. X-ray diffraction (XRD) analysis revealed that most crystals demonstrated a characteristic A-type arrangement. Debranching and crystallization processes enhanced the crystallinity of the samples. The specific crystal arrangement (A- or B-type) depended on the crystallization conditions. A 15 min heating of NWMS in a boiling water bath increased the digestible fraction to over 90 %, while the samples subjected to debranching and crystallization showed an increase to only about 45 %. A linear correlation between starch fractions and enthalpy was also observed.


Assuntos
Amilopectina , Zea mays , Temperatura , Zea mays/química , Cristalização , Difração de Raios X , Amilopectina/química , Amido/química , Amido Resistente
2.
Carbohydr Polym ; 209: 230-238, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30732804

RESUMO

Characterization of the rheological properties of Chinese quince seed gum (CQSG) is fundamental when using it in food production. In the present paper, the chemical compositions and the rheological properties of CQSG at different concentrations, types of salts, temperatures and pH values were characterized by using shear or dynamic rheological experiments. The results demonstrated that uronic acid content of CQSG (31.7%) was high and different concentration CQSG solutions presented Newtonian plateaus followed by shear thinning regions. The viscosities of the gum solutions decreased with the addition of any salt, with increase in temperature and at extreme pH values (3 and 11). The stress and frequency sweep tests demonstrated a unique result in that the crossover frequency shifted to a higher value when the CQSG solution concentration increased. It is the basis for CQSG product development and quality control for its potential applications.


Assuntos
Elasticidade , Gomas Vegetais/química , Reologia , Rosaceae/química , Sementes/química , Concentração de Íons de Hidrogênio , Concentração Osmolar , Temperatura , Viscosidade
3.
Carbohydr Polym ; 185: 96-104, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29421064

RESUMO

In this investigation, a variety of innovative pH-sensitive polymers consisting of Chinese quince seed gum (CQSG) and poly (N,N-diethylacryl amide-co-methacrylic acid) were synthesized via free radical polymerization for controlled drug delivery. The resultant hydrogel polymers were characterized by scanning electron microscopy and X-ray diffraction, analyzed by Fourier-transform infrared spectroscopy, and confirmed with thermogravimetry. Results suggested the hydrogel polymers were composed of CQSG chains physically entangled in poly (N,N-diethylacryl amide-co-methacrylic acid) networks. Swelling properties of these hydrogels were strongly affected by the contents of CQSG and crosslinkers. The drug delivery applications of the hydrogels were evaluated using bovine serum albumin (BSA) as a model drug in vitro release. It was determined that BSA release from the hydrogels was pH-sensitive under simulated gastrointestinal conditions. All of these attributes imply that the new proposed CQSG/poly (N,N-diethylacryl amide-co-methacrylic acid) hydrogel polymers can be used as a good medium for oral delivery of proteinaceous drugs.


Assuntos
Acrilamidas/química , Portadores de Fármacos/química , Hidrogéis/química , Metacrilatos/química , Gomas Vegetais/química , Rosaceae/química , Sementes/química
4.
Huan Jing Ke Xue ; 28(8): 1675-80, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17926392

RESUMO

Comparison research of different constructed wetland types to treat lake Wulihu water was carried out. Under the condition of the loading rates 0.8 m3/(m2 x d), the removal efficiencies of the vertical flow wetland (VFW), subsurface flow wetland (SFW) and free surface wetland(FSW) had the following results: To ammonia nitrogen (NH4(+)-N) the average removal rates were 33.2%, 27.4% and 14.1%, respectively; To total nitrogen (TN) the average removal rates were 52.3% , 50.1% and 19.2%, respectively; To total phosphorus (TP) the average removal rates were 58.8%, 57.9% and 26.3%, respectively; To permanganate index the average removal rates were 37.2%, 38.3% and 14.8%, respectively; To chlorophyll a (Chl-a) the average removal rates were 86.9%, 96.1% and 55.3%, respectively. Obviously, VFW and SFW are more effective than FSW at treating eutrophicated water such as Lake Wulihu which with characters of low organically pollution and with high nitrogen and phosphorus pollution, and the VFW is the most effective on the removal of NH4(+)-N, TN and TP. SFW is the most effective on the removal of permanganate index and Chl-a. The effluent stability of VFW is better than SFW, and the SFW is better than FSW.


Assuntos
Eutrofização , Nitrogênio/metabolismo , Fósforo/metabolismo , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Amônia/isolamento & purificação , Amônia/metabolismo , Biodegradação Ambiental , China , Clorofila/isolamento & purificação , Clorofila/metabolismo , Clorofila A , Água Doce/análise , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Projetos Piloto , Movimentos da Água , Poluentes Químicos da Água/análise
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