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1.
Int J Nanomedicine ; 15: 5083-5095, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764938

RESUMO

Background: ß-glucans are chiral polysaccharides with well-defined immunological properties and supramolecular wrapping ability of its chiral feature. However, the exploitation of chiral properties of these nanoparticles in drug delivery systems was seldom conducted. Methods: ß-glucan molecules with different chain lengths were extracted from yeast Saccharomyces cerevisiae and thereafter modified. In a conformation transition process, these ß-glucan molecules were then self-assembled with anti-cancer drug doxorubicin into nanoparticles to construct drug delivery systems. The chiral interactions between the drug and carriers were revealed by circular dichroism spectra, ultraviolet and visible spectrum, fourier transform infrared spectroscopy, dynamic light scattering and transmission electron microscope. The immune-potentiation properties of modified ß-glucan nanoparticles were evaluated by analysis of the mRNA expression in RAW264.7 cell model. Further, the antitumor efficacy of the nanoparticles against the human breast cancer were studied in MCF-7 cell model by cellular uptake and cytotoxicity experiments. Results: ß-glucan nanoparticles can activate macrophages to produce immune enhancing cytokines (IL-1ß, IL-6, TNF-α, IFN-γ). A special chirality of the carriers in diameter of 50~160 nm can also associate with higher drug loading ability of 13.9% ~38.2% and pH-sensitive release with a change of pH from 7.4 to 5.0. Cellular uptake and cytotoxicity experiments also prove that the chiral-active ß-glucan nanoparticles can be used in anti-cancer nanomedicine. Conclusion: This work demonstrates that ß-glucans nanoparticles with special chiral feature which leading to strong immunopotentiation ability and high drug loading efficiency can be developed as a novel type of nanomedicine for anti-cancer treatment.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/administração & dosagem , beta-Glucanas/imunologia , Adjuvantes Imunológicos/química , Animais , Antineoplásicos/imunologia , Dicroísmo Circular , Portadores de Fármacos/química , Humanos , Células MCF-7 , Camundongos , Nanopartículas/química , Células RAW 264.7 , Saccharomyces cerevisiae/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , beta-Glucanas/química
2.
Food Chem ; 332: 127390, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32603922

RESUMO

Revalorization of mushroom by-product (stalks of A. bisporus) by extracting its components is proposed. The extraction kinetics at 25 °C of ergosterol, phenolic compounds and antioxidant activity by mechanical agitation (at 130 rpm) and ultrasound assistance (at 182 and 321 W/L) in 70 and 96% v/v ethanol/water solutions during 30 min were evaluated and satisfactorily modelled, using the Weibull model (mean relative error ≤ 7.8%). The effect of the ethanol concentration was high in the ergosterol extraction yield (2 times higher yields in 96% than in 70%) but slight in those of phenolic compounds and antioxidant activity. Ultrasound assistance promoted considerable yield increases (up to 2 times higher in ergosterol, 46% in phenolic compounds and 25% in antioxidant activity) depending on the ethanol concentration and ultrasound power density. The residues after extraction were characterized and constituted a potential source of high value polysaccharides as ß-glucans (average 12.2 ± 1.7g/100 g dm).


Assuntos
Agaricales/química , Antioxidantes/química , Ergosterol/química , Extração em Fase Sólida/métodos , beta-Glucanas/química , Agaricales/metabolismo , Antioxidantes/isolamento & purificação , Ergosterol/isolamento & purificação , Etanol/química , Modelos Teóricos , Fenóis/química , Sonicação
3.
Food Chem ; 324: 126858, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353656

RESUMO

Wheat flour noodles are sometimes fortified with ß-glucan for nutritional value, but this can decrease eating quality. The contributions of ß-glucan and starch molecular fine structure to physicochemical properties of wholemeal oat flour and to the texture of oat-fortified white salted noodles were investigated here. Hardness of oat-fortified noodles was controlled by the longer amylopectin chains (DP ≥ 26) and amount of longer amylose chains (DP ≥ 1000). Higher levels of ß-glucan, in the range from 3.1 to 5.2%, result in increased noodle hardness. Pasting viscosities of wholemeal oat flour positively correlate with the hardness of oat-fortified noodles. The swelling power of oat flour is not correlated with either pasting viscosities of oat flour or noodle hardness. Longer amylopectin chains and the amount of longer amylose chains both control the pasting viscosities of oat flour, which in turn affect noodle texture. This provides new means, based on starch and ß-glucan molecular structure, to choose oats with optimal starch structure and ß-glucan content for targeted oat-fortified noodle quality.


Assuntos
Avena/metabolismo , Amido/química , Triticum/metabolismo , beta-Glucanas/química , Amilopectina/química , Amilose/química , Farinha/análise , Dureza , Viscosidade
4.
PLoS One ; 15(5): e0233447, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32442194

RESUMO

The food industry is currently shown the concern with low-fat products. This study aims to evaluate the properties of oat ß-glucan(OG)-marine collagen peptide (MCP) mixed gels induced by high pressure at different ratios, pressures, pH levels and the superiority of application in the sausage. The results indicated that the typical gel with high levels of hardness, cohesiveness, springiness, and chewiness, as well as high water holding and oil adsorption capacities was formed using the OG/MCP ratio of 10:1 under 400 MPa at pH 6.0. The mixed gel replacing with 50% fat significantly increased the springiness and chewing(P<0.05), and sausages with 80% mixed gel were significantly juicier than that of the control sausage(P<0.05). Therefore, OG-MCP mixed gel could be used in the reformulation of low-fat meat products to enhance their safety and nutritional value.


Assuntos
Avena/química , Colágeno/química , Gorduras na Dieta/análise , Produtos da Carne/análise , beta-Glucanas/química , Animais , Cor , Culinária , Dieta com Restrição de Gorduras , Manipulação de Alimentos , Indústria Alimentícia , Géis , Humanos , Reologia , Sus scrofa , Paladar
5.
J Food Sci ; 85(6): 1689-1698, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32458491

RESUMO

Three hulless barley varieties were grown under normal conditions during 2017/2018 and 2018/2019, to improve their agronomic yield, and to assess how the genotype influences ß-glucan contents, and its structural, thermal, rheological, and functional properties, as intended to be used in food applications. The extracted gums with hot water at 55 °C and pH 8.0, showed contents from 5.75% to 6.41% (w/w), and concentrations from 68.55% to 79.29% of ß-glucan, with some starch and protein impurities. The results of the agronomic trail indicated the highly significant (P ≤ 0.01) influence of the genotype on all studied characteristics, and on the ß-glucan contents (0.28** and 0.33** ) at both seasons. The morphology of the three gums was significantly different in the distribution and structure of networks. Peak intensities of the -OH and -CH groups and CH2 stretching were higher and wider in Giza129 and Giza131. ß-Glucan networks melt from 71.5 to 87.18 °C, and Giza131 exhibited the highest thermal stability. The aqueous dispersions (1%) of ß-glucan gums exhibited a non-Newtonian behavior, and Giza130 presented the highest significant (P ≤ 0.05) apparent viscosity (η) and foaming stability. Giza129 showed the highest significant water and fat binding capacities, whereas Giza131 showed the highest significant foaming capacity. ß-Glucan gums showed different potentials in food applications as fat replacers, stabilizers, thickeners, and foaming agents in food systems. This study suggests planting the proper barley variety in breeding and genetic improvement programs to supply the food industry with the expected ß-glucan content with consistent structural, thermal, rheological, and functional properties. PRACTICAL APPLICATION: ß-Glucans play an important technological role in processed foods. Little current information is available on ß-glucan contents, and its potentiality on food applications, as influenced by variability among hulless barley genotypes. Accordingly, knowledge of ß-glucan levels in barley varieties is a valuable attribute for both consumers and food processors, and it will create an opportunity for scientific cooperation between food technologist and breeders to identify the suitable barley varieties to be used in breeding programs, to obtain barley with required ß-glucan contents, targeted for specific end uses.


Assuntos
Hordeum/química , beta-Glucanas/química , Indústria Alimentícia , Genótipo , Hordeum/classificação , Hordeum/genética , Estrutura Molecular , Amido/análise , Viscosidade
6.
Food Chem ; 319: 126232, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32197213

RESUMO

Yeast ß-glucan (YG) adsorbs off-odor in silver carp mince due to its more porous structure. To explore adsorption behavior and mechanism, adsorption kinetics and thermodynamics of YG for 3 off-odor compounds (hexanal, 1-octen-3-ol and nonanal) were investigated by pseudo-first/second-order models and isothermal equations (Langmuir, Freundlich and Redlich-Peterson). Kinetic experiments indicated adsorption process followed pseudo-first-order model. Adsorption isotherms indicated 3 off-odors could easily be adsorbed by YG and adsorption capacity was in the order of 1-octene-3-ol > hexanal > nonanal. Thermodynamic result suggested adsorption of 3 off-odors by YG was endothermic and spontaneous, and was driven predominantly by physisorption and hydrophobic interaction. Consequently, the contents of 3 off-odors that released from mince/YG complex decreased by 22.8%, 29.9%, and 24.5% (p < 0.05), respectively, compared with those from mince without YG. Therefore, the addition of YG enhanced the binding capability to off-odors, thus reducing the release of off-odor from silver carp mince.


Assuntos
Carpas , Saccharomyces cerevisiae/química , beta-Glucanas/química , Adsorção , Animais , Interações Hidrofóbicas e Hidrofílicas , Cinética , Odorantes/análise , Termodinâmica
7.
Carbohydr Polym ; 234: 115920, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070539

RESUMO

Vitamin C (VC) is an indispensable nutrient for human health. However, poor chemical stability in gastric environment restricts its full assimilation by intestine. It is important to construct a safe carrier that can protect VC from the gastric fluid and sustainably release it in intestine. Herein, we designed a novel polyelectrolyte complex (PEC) hydrogel through self-assembly of salecan and chitosan. PEC structure formed by electrostatic interactions was confirmed by FT-IR, XRD, XPS and TGA. Their swelling, morphology, rheology, cytocompatibility and biodegradation were well investigated. In particular, VC released in a controlled and pH-dependent manner. The release amount in simulated intestinal fluid (SIF) was significantly higher than simulated gastric fluid (SGF), and can be maintained at high level in blood after 6 h. Release mechanism agreed well with Ritger-Peppas model. The purpose of this study was to develop a smart nutrient delivery platform for targeted release of VC in intestinal condition.


Assuntos
Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Quitosana/química , Hidrogéis/química , Polieletrólitos/química , beta-Glucanas/química , Células 3T3-L1 , Animais , Sobrevivência Celular , Células Cultivadas , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Hidrogéis/síntese química , Cinética , Masculino , Camundongos , Estrutura Molecular , Tamanho da Partícula , Polieletrólitos/síntese química , Reologia , Propriedades de Superfície
8.
Adv Pharmacol ; 87: 277-299, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32089236

RESUMO

Fungal bioactive polysaccharides are well known and have been widely used in Asia as a part of the traditional diet and medicine. In fact, some biopolymers (mainly ß-glucans or glycoconjugate) have already made their way to the market as antitumor or immunostimulating drugs. In the last decades, the relationship between structure and activity of polysaccharides and their detailed mode of action have been the core of intense research to understand and utilize their medicinal properties. Most of the antitumor polysaccharides belong to conserved ß-glucans, with a linear ß-(1→3)-glucan backbone and attached ß-(1→6) branch. Structurally different ß-glucans appear to have different affinities toward their receptors and thus generate markedly different host responses. However, their antitumor activities are mainly influenced by molecular mass, degree of branching, conformation, and structure modification of the polysaccharides. ß-Glucans act on several immune receptors including Dectin-1, complement receptor (CR3) and TLR-2/6, then trigger both innate and adaptive response and enhance opsonic and nonopsonic phagocytosis. Various receptor interactions explain the possible mode of actions of polysaccharides.


Assuntos
Polissacarídeos Fúngicos/farmacologia , Animais , Antineoplásicos/farmacologia , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/imunologia , Humanos , Modelos Biológicos , Conformação Molecular , Relação Estrutura-Atividade , beta-Glucanas/química
9.
Biochemistry ; 59(5): 682-693, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31899625

RESUMO

(1,3)-ß-d-Glucan synthase (GS) catalyzes formation of the linear (1,3)-ß-d-glucan in the fungal cell wall and is a target of clinically approved antifungal antibiotics. The catalytic subunit of GS, FKS protein, does not exhibit significant sequence homology to other glycosyltransferases, and thus, significant ambiguity about its catalytic mechanism remains. One of the major technical barriers in studying GS is the absence of activity assay methods that allow characterization of the lengths and amounts of (1,3)-ß-d-glucan due to its poor solubility in water and organic solvents. Here, we report a successful development of a novel GS activity assay based on size-exclusion chromatography coupled with pulsed amperometric detection and radiation counting (SEC-PAD-RC), which allows for the simultaneous characterization of the amount and length of the polymer product. The assay revealed that the purified yeast GS produces glucan with a length of 6550 ± 760 mer, consistent with the reported degree of polymerization of (1,3)-ß-d-glucan isolated from intact cells. Pre-steady state kinetic analysis revealed a highly efficient but rate-determining chain elongation rate of 51.5 ± 9.8 s-1, which represents the first observation of chain elongation by a nucleotide-sugar-dependent polysaccharide synthase. Coupling the SEC-PAD-RC method with substrate analogue mechanistic probes provided the first unambiguous evidence that GS catalyzes non-reducing end polymerization. On the basis of these observations, we propose a detailed model for the catalytic mechanism of GS. The approaches described here can be used to determine the mechanism of catalysis of other polysaccharide synthases.


Assuntos
Parede Celular/metabolismo , Glucosiltransferases/metabolismo , Saccharomyces cerevisiae/metabolismo , beta-Glucanas/metabolismo , Biocatálise , Cromatografia em Gel , Glucosiltransferases/química , Cinética , Polimerização , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/enzimologia , Especificidade da Espécie , beta-Glucanas/química , beta-Glucanas/isolamento & purificação
10.
Carbohydr Res ; 488: 107909, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31968294

RESUMO

Under optimized conditions, the lactic acid bacterium Lactobacillus fermentum Lf2 secretes up to 2 gL-1 of a mixture of polysaccharides into the fermentation medium when grown on sucrose. Earlier studies had shown that the mixture is biologically active and work was undertaken to characterise the polysaccharides. Preparative size exclusion chromatography was used to separate a high molecular mass ß-glucan (weight average mass of 1.23 × 106 gmol-1) from two medium molecular mass polysaccharides (weight average mass of 8.8 × 104 gmol-1). Under optimized growth conditions, the medium molecular mass polysaccharides accounted for more than 75% of the mixture by weight. Monomer, linkage analysis and NMR spectroscopy of the medium molecular mass polysaccharides, and material isolated after their Smith degradation, was used to identify the structure of the component polysaccharides. The mixture contains two novel polysaccharides. The first has a main chain of ß-1,6-linked galactofuranoses which is non-stoichiometrically 2-O-glucosylated. The degree of substitution at the 2-position, with α-D-Glcp, depends on the fermentation conditions; under optimized conditions greater than 80% 2-O-α-D-glucosylation was observed. The second polysaccharide is a heteroglycan with four monosaccharides in the repeat unit: residual signals in the NMR suggest that the sample also contains trace amounts (<3%) of cell wall polysaccharides.


Assuntos
Lactobacillus fermentum/crescimento & desenvolvimento , Polissacarídeos Bacterianos/química , beta-Glucanas/química , Sequência de Carboidratos , Fermentação , Lactobacillus fermentum/química , Peso Molecular
11.
Mater Sci Eng C Mater Biol Appl ; 108: 110379, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923932

RESUMO

Curdlan, an insoluble and neutral polysaccharide, was produced from Agrobacterium sp. ATCC 31750 and chemically modified with dimethylaminoethyl (DMAE) group to introduce gene binding ability. The resulting DMAE-curdlan was crosslinked with curdlan nanoparticles using epichlorohydrin. The prepared nanoparticles are spherical with an average diameter of 523 ±â€¯195 nm, stable and are highly biocompatible with differentiated THP-1 macrophages with viability of above 90%. They are taken up more efficiently by RAW 264.7 macrophage cells than by L929 fibroblast cells. They increase the expression of M1 macrophage marker genes, TNFα and CXCL10, and decrease the expression of M2 marker, CD206, indicating their ability to activate M1 phenotype and aid in tumor regression. They are also capable of delivering siRNA to human macrophage-like cells efficiently and inhibit ~59% of the expression of target MMP-9 protein. These results indicate that this modified curdlan-based nanoparticle is a promising vehicle for the delivery of siRNAs to macrophages, which could open up treatment strategies for a range of diseases.


Assuntos
Etilaminas/química , Técnicas de Transferência de Genes , Macrófagos/metabolismo , Nanopartículas/química , RNA Interferente Pequeno/administração & dosagem , beta-Glucanas/química , Animais , Biomarcadores/metabolismo , Morte Celular/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Camundongos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Eletricidade Estática , Células THP-1 , Transfecção
12.
Carbohydr Polym ; 231: 115685, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888856

RESUMO

The effects of fermentation by Lactobacillus plantarum dy-1 on the main structural changes of barley ß-glucan and their in vitro activities were studied. Molecular characteristics, infrared spectroscopy, monosaccharide composition, methylation, 1D and 2D-NMR analyses and scanning electron microscopy revealed that both (raw barley ß-glucan) RBG and fermented barley ß-glucan (FBG) are polysaccharides predominanted by ß-(1→3) and ß-(1→4) linked glucose. However, different molecular weight (decreasing from 1.13×105 D to 6.35×104 D), the ratio of the ß-(1→3) residues to the ß-(1→4) residues (ranging from 1:1.98-1:2.50 to 1:1.8-1:2.24) and microstructure features (transforming from a rod-like to sheet-like structure) were observed. Bioassay results showed that FBG exhibited improved inhibitory activities of α-amylase, α-glucosidase and lipase, as well as the adsorption of cholesterol under acidic conditions compared to RBG. These results suggested that fermentation may enhance in vitro physiological activities of barley ß-glucan, especially related to glucose and lipid metabolism.


Assuntos
Hordeum/química , Lactobacillus plantarum/química , beta-Glucanas/química , Colesterol/química , Fermentação , Lipase/antagonistas & inibidores , Lipase/química , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/efeitos dos fármacos , beta-Glucanas/farmacologia
13.
Molecules ; 25(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906359

RESUMO

Isoflavones in soybeans are well-known phytoestrogens. Soy isoflavones present in conjugated forms are converted to aglycone forms during processing and storage. Isoflavone aglycones (IFAs) of soybeans in human diets have poor solubility in water, resulting in low bioavailability and bioactivity. Enzyme-mediated glycosylation is an efficient and environmentally friendly way to modify the physicochemical properties of soy IFAs. In this study, we determined the optimal reaction conditions for Deinococcus geothermalis amylosucrase-mediated α-1,4 glycosylation of IFA-rich soybean extract to improve the bioaccessibility of IFAs. The conversion yields of soy IFAs were in decreasing order as follows: genistein > daidzein > glycitein. An enzyme quantity of 5 U and donor:acceptor ratios of 1000:1 (glycitein) and 400:1 (daidzein and genistein) resulted in high conversion yield (average 95.7%). These optimal reaction conditions for transglycosylation can be used to obtain transglycosylated IFA-rich functional ingredients from soybeans.


Assuntos
Deinococcus/enzimologia , Glucosiltransferases/metabolismo , Isoflavonas/química , Extratos Vegetais/química , Soja/química , beta-Glucanas/química , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Vetores Genéticos , Genisteína/química , Glucosiltransferases/genética , Glicosilação , Isoflavonas/biossíntese , Isoflavonas/isolamento & purificação , Isoflavonas/farmacocinética , Espectrometria de Massas , Fitoestrógenos/química , Extratos Vegetais/isolamento & purificação , beta-Glucanas/farmacocinética
14.
Animal ; 14(2): 269-276, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31405398

RESUMO

Rheological properties of digesta play a role in digesta passage kinetics through the gastrointestinal tract, in turn affecting nutrient absorption kinetics. Therefore, we studied the effects of diet viscosity on digesta passage and physicochemical properties in pigs. Twenty male growing pigs (35 kg body weight at the start) were assigned to one of five diets with increasing dietary concentrations of ß-glucans (BG; from 0 % to 10 %), in exchange for maize starch. After a 17-day adaptation period, pigs were euthanised and the mean retention time (MRT) of digesta solids (TiO2) and liquids (Cr-EDTA) in the stomach, and proximal and distal half of the small intestine was quantified. In the stomach, the MRT of liquids, but not of solids, increased when dietary BG level increased (6 min per % dietary BG, P = 0.008 and R2 = 0.35). Concomitantly, stomach DM content (5 g/kg per % dietary BG, P < 0.001 and R2 = 0.53) and apparent digesta viscosity (56 Pa × s at 1/s shear rate per % dietary BG, P = 0.003 and R2 = 0.41) decreased. In the proximal half of the small intestine, no effects of dietary BG level were observed. In the distal half of the small intestine, water-binding capacity (WBC) of digesta increased (0.11 g/g digesta DM per % dietary BG, P = 0.028 and R2 = 0.24) and starch digestibility decreased (0.3% per % dietary BG, P = 0.034 and R2 = 0.23) when dietary BG level increased. In the colon, apparent digesta viscosity at 45/s shear rate increased (0.1 Pa × s per % dietary BG, P = 0.03 and R2 = 0.24) in the proximal half of the colon, and digesta WBC increased (0.06 g/g digesta DM per % dietary BG, P = 0.024 and R2 = 0.26) in the distal half of the colon when dietary BG level increased. To conclude, increasing dietary BG level caused the MRT of liquids, but not that of solids, to increase in the stomach, resulting in reduced separation of the solid and liquid digesta fractions. This caused dilution of the stomach content and reduction in digesta viscosity when dietary BG levels increased. Effects of dietary BG level on physicochemical properties in the proximal small intestine were absent and may have been due to a low DM content. The WBC of digesta in the distal small intestine and colon increased when dietary BG level increased, as did apparent digesta viscosity in the proximal colon. This likely reflects the concentration of BG in digesta when moving through the gastrointestinal tract.


Assuntos
Ração Animal/análise , Suínos/fisiologia , beta-Glucanas/química , Animais , Peso Corporal , Dieta/veterinária , Digestão , Conteúdo Gastrointestinal/química , Trato Gastrointestinal/fisiologia , Intestino Delgado/fisiologia , Cinética , Masculino , Reologia , Estômago/fisiologia , Viscosidade
15.
Food Chem ; 310: 125983, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31835225

RESUMO

In this study, the effects of the addition of various polysaccharides (konjac gum, gellan gum, and curdlan gum) on the rheological and textural properties of calcium sulfate-induced soy protein isolate gels were investigated. The incorporation of konjac gum and curdlan gum at 0.3 and 0.5% (w/v) concentrations and gellan gum at 0.5% concentration significantly enhanced (P < 0.05) the hardness and water-holding capacity of the resultant gels. The increased elastic moduli during and after gelation, reinforced fracture stress, and lowered onset gelling temperature indicated that the addition of the abovementioned polysaccharides strengthened gel structures and accelerated gelation. Confocal laser scanning microscopy analysis revealed that the polysaccharides also improved gel microstructures, with the gels containing konjac gum displaying the highest homogeneity. The findings of this study may provide important information for the development of innovative soy protein isolate-based gel products with improved texture.


Assuntos
Sulfato de Cálcio/química , Polissacarídeos/química , Proteínas de Soja/química , Amorphophallus/química , Módulo de Elasticidade , Géis/química , Polissacarídeos Bacterianos/química , Reologia , Proteínas de Soja/isolamento & purificação , Temperatura , Água/química , beta-Glucanas/química
16.
Am J Clin Nutr ; 111(2): 319-328, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31828287

RESUMO

BACKGROUND: The viscosity of oat ß-glucan (OBG) determines its effect on serum cholesterol and glycemic responses, but whether OBG viscosity affects gastric emptying, appetite, and ad libitum food intake is unknown. OBJECTIVES: We aimed to determine the effect of altering the amount or molecular weight (MW) and, hence, viscosity of OBG in a breakfast meal on the primary endpoint of food intake at a subsequent meal. METHODS: Overnight-fasted males (n = 16) and nonpregnant females (n = 12) without diabetes, aged 18-60 y, with BMI 20.0-30.0 kg/m² who were unrestrained eaters participated in a double-blind, randomized, crossover study at a contract research organization. Participants consumed, in random order, breakfast meals equivalent in weight, energy, and macronutrients consisting of white-bread, butter, jam, and 2% milk plus hot cereal [Cream of Rice (CR), or instant-oatmeal plus either 3 g oat-bran (2gOBG), 10 g oat-bran (4gOBG), or 10 g oat-bran plus ß-glucanase (4gloMW) to reduce OBG MW and viscosity compared with 4gOBG]. Gastric emptying, subjective appetite, and glucose, insulin, ghrelin, and peptide tyrosine tyrosine (PYY) responses were assessed for 3 h and then subjects were offered an ad libitum lunch (water and pizza). RESULTS: Pizza intakes (n = 28) after CR, 2gOBG, 4gOBG, and 4gloMW (mean ± SEM: 887 ± 64, 831 ± 61, 834 ± 78, and 847 ± 68 kcal, respectively) were similar (nonsignificant). Compared with CR, 4gOBG significantly reduced glucose (78 ± 10 compared with 135 ± 15 mmol × min/L) and insulin (14.0 ± 1.6 compared with 26.8 ± 3.5 nmol × min/L) incremental area-under-the-curve and delayed gastric-emptying half-time (geometric mean: 285; 95% CI: 184, 442, compared with geometric mean: 105; 95% CI: 95, 117 min), effects not seen after 4gloMW. Subjective appetite, PYY, and ghrelin responses after 2gOBG, 4gOBG, and 4gloMW were similar to those after CR. CONCLUSIONS: The results demonstrate that OBG viscosity determines its effect on postprandial glucose, insulin, and gastric emptying. However, we were unable to demonstrate a significant effect of OBG on appetite or food intake, regardless of its viscosity.This trial was registered at clinicaltrials.gov as NCT03490851.


Assuntos
Apetite/efeitos dos fármacos , Avena , Glicemia/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Insulina/sangue , beta-Glucanas/química , Adolescente , Adulto , Desjejum , Estudos Cross-Over , Método Duplo-Cego , Feminino , Grelina/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo YY/sangue , Viscosidade , Adulto Jovem , beta-Glucanas/administração & dosagem
17.
Food Funct ; 11(1): 585-595, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31858092

RESUMO

The physicochemical characteristics of beta-glucans determine the immune responses of the intestines and whole body. It is hypothesized that glucans with different molecular weights have diverse modes of action on LPS-mediated immune activity. This study aimed to verify the immune-modulatory effects of two types of beta-glucans in LPS-induced weaned piglets. The results indicated that dietary beta-glucan supplementation could prevent losses in body weight gain caused by LPS challenge. Supplementation with different molecular weights of beta-glucans decreased the production of IL-1ß and TNF-α and increased IL-10 production, which is likely associated with key factors such as TLR4 and NF-κB. High-molecular-weight beta-glucans seemed to have a strong functional capacity to modulate the innate immune response through the Dectin-1 receptor. Therefore, the results indicate that supplementing piglets with Agrobacterium sp. ZX09 beta-glucans inhibits LPS-mediated depression in the growth performance and plays a protective role during LPS challenge possibly via the Dectin-1 receptor and the TLR4/NF-κB pathway. The results reveal the potential therapeutic activity of purified Agrobacterium sp. ZX09 beta-glucan following experimental LPS infusion.


Assuntos
Agrobacterium/química , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Lipopolissacarídeos/efeitos adversos , beta-Glucanas/administração & dosagem , beta-Glucanas/química , Animais , Imunidade Inata/efeitos dos fármacos , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Peso Molecular , NF-kappa B/genética , NF-kappa B/imunologia , Suínos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Desmame
18.
Food Chem ; 307: 125548, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31654949

RESUMO

Due to their high content of ß-glucan, the consumption of oat products can contribute to a healthy diet. Roasting may improve sensory properties but could also affect the nutritional value of oat products. Therefore, the aim of the present study was to analyse the impact of different roasting conditions (140-180 °C, approx. 20 min) on sensory quality, health-related compounds (e.g. acrylamide, ß-glucan) and viscosities of oat kernels and flakes. Roasting resulted in oat flakes with improved sensory properties. Acrylamide formation increased with higher roasting temperatures in kernels, thin and thick flakes. Contents of fat, protein, starch and ß-glucan were not affected by roasting, whereas dietary fibre fractions were marginally modulated. Viscosities were significantly reduced with increasing roasting temperatures. The results indicate that roasting up to 160 °C is a processing technique with potential to generate oat products with improved sensory quality and favourable nutritional composition.


Assuntos
Avena/química , Acrilamida/química , Avena/metabolismo , Fibras na Dieta , Saúde , Temperatura Alta , Amido/química , Amido/metabolismo , Viscosidade , beta-Glucanas/química , beta-Glucanas/metabolismo
19.
Food Chem ; 306: 125632, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606634

RESUMO

In this study, we have developed a novel polyelectrolyte complex (PEC) hydrogel that could be easily prepared by self-assembly of two food-grade polysaccharides salecan and N,N,N-trimethyl chitosan (TMC). The electrostatic interactions between two polysaccharides were driving force in complexation processes and have been demonstrated by FTIR, XRD, XPS and TGA. The swelling capacity, morphology and rheological property of the hydrogels could be well tuned by controlling salecan/TMC ratio. Green tea polyphenols (GTP) was efficiently encapsulated into PEC hydrogels and liberated in a sustained pattern. The amount of GTP released in simulated intestinal fluid (SIF) was significantly higher than simulated gastric fluid (SGF). Increasing salecan/TMC ratio also markedly enhanced GTP release amount. Release exponent n obtained in SGF indicated a Fickian diffusion, while in SIF an anomalous transport occurred. The release mechanism was well-fitted with Ritger-Peppas model. Taken together, these PEC hydrogels could be suitable carriers for intestinal targeted nutrient delivery.


Assuntos
Polieletrólitos/química , Polifenóis/química , Polissacarídeos/química , Chá/química , Difusão , Hidrogéis/química , Concentração de Íons de Hidrogênio , beta-Glucanas/química
20.
Food Chem ; 309: 125791, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31699554

RESUMO

The aim of this study was to investigate the effect of phosphorylation on the antioxidant activity of (1 → 3)-ß-d-glucan from yeast cell wall. Alkali-insoluble (1 → 3)-ß-d-glucan was extracted from yeast cell wall by an acid-base method. It was found that the purity of the sample was greatly improved after the precipitation was treated with alkali at 90 ℃ and then by acetic acid, which was about 96.5%. Phosphorylated (1 → 3)-ß-d-glucan was prepared. Infrared (IR) spectra and nuclear magnetic resonance spectra (NMR) confirmed the successful introduction of phosphate into glucan. The substitution degree of phosphate was 0.18. The phosphorylated (1 → 3)-ß-d-glucan could significantly increase SOD and CAT contents in serum, liver and brain of mice, and reduce MDA level in serum, liver and brain to a certain extent in vivo. This lays a solid foundation for the research and development of phosphorylated (1 → 3)-ß-d-glucan antioxidant.


Assuntos
Antioxidantes/metabolismo , beta-Glucanas/química , Animais , Antioxidantes/química , Catalase/sangue , Catalase/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Espectroscopia de Ressonância Magnética , Malondialdeído/sangue , Malondialdeído/metabolismo , Camundongos , Fosforilação , Saccharomyces cerevisiae/metabolismo , Espectrofotometria Infravermelho , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo
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