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1.
Food Chem ; 300: 125221, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351256

RESUMO

In this study, water-soluble curdlan products (Cur and Cur-D) were prepared by an alkali-neutralization treatment process, after which ferulic acid (FA)-grafted Cur conjugates (Cur-g-FA and Cur-D-g-FA) were fabricated in the presence and absence of salt by adopting an approach involving free-radicals generated by the ascorbic acid/hydrogen peroxide redox pair under an inert atmosphere. Results showed that FA was successfully grafted onto the C-6 and C-4 positions of the Cur chains through covalent linkages and that the presence of salt exerted minor influences on the grafting ratios and structural characterizations of the products. Cur-g-FA and Cur-D-g-FA showed decreased crystallinity, thermal stability, and rheological properties, as well as a distinct surface morphology, when compared with those of native Cur. However, Cur-g-FA and Cur-D-g-FA also exhibited remarkably enhanced free-radical scavenging ability and antioxidant capacity in vitro. These results indicate that FA-grafted Cur conjugates have great potential application in the field of functional foods.


Assuntos
Antioxidantes/química , Ácidos Cumáricos/química , beta-Glucanas/química , Antioxidantes/farmacologia , Ácido Ascórbico/química , Radicais Livres/química , Peróxido de Hidrogênio/química , Oxirredução , Reologia , Solubilidade , Propriedades de Superfície , Água/química
2.
Food Chem ; 299: 125128, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299517

RESUMO

A novel strategy was used to produce inulin fructotransferase from Arthrobacter aurescens (Aa-IFTase) embedded in curdlan-based mesoporous silica microspheres (CMSiM-Aa-IFTase). The CMSiM-Aa-IFTase was constructed by co-entrapping cross-linked Aa-IFTase aggregates and curdlan into biomemitic silica, and the curdlan was subsequently removed by digestion with endo-ß-1,3-glucanase. During this process, the curdlan served as an agent to introduce pores in silica microspheres. The resulting CMSiM-Aa-IFTase showed higher stability and activity than free Aa-IFTase and mCLEAs-Aa-IFTase (modified cross-linked enzyme aggregates with Aa-IFTase). Furthermore, the CMSiM-Aa-IFTase displayed good reusability and excellent storage stability. The excellent catalytic performances were due to the combinational structure from the cross-linked enzyme aggregates and hard shell of mesoporous silica microspheres, which might decrease the negative interaction between support and enzyme, and improve the mechanical properties. The CMSiM-Aa-IFTase was applicable for efficient production of Difructose Anhydride III (DFA III), and this approach should be highly valuable for preparing various mesoporous composites for catalysis.


Assuntos
Arthrobacter/enzimologia , Dissacarídeos/metabolismo , Hexosiltransferases/química , Hexosiltransferases/metabolismo , beta-Glucanas/química , Catálise , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Hexosiltransferases/genética , Microesferas , Dióxido de Silício
3.
Food Chem ; 299: 125037, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31279128

RESUMO

Immobilization of enzymes is an essential strategy with outstanding prospects in biocatalytic processes. Nontoxic, inexpensive immobilized enzyme approach is especially important for food enzymes. We here demonstrate that a carbohydrate-binding module family 56 domain (CBM56-Tag) mediates the immobilization of fusion enzymes with the curdlan (ß-1,3-glucan) particle support, thereby enabling the one-step immobilization-purification of target enzymes. CBM56-Tag exhibits an immunoglobulin-like ß-sandwich fold, which can be adsorbed by curdlan via hydrogen bond-mediated binding. The maximum adsorption capacity of a fusion chitosanase (CBM56-GsCsn46A) on curdlan is 50.72 mg/g. The immobilized enzyme could be directly used in the packed-bed reactor. This immobilization strategy utilizes a natural polysaccharide without any treatment, avoiding the negative environmental effects. Moreover, the one step immobilization-purification simplifies the purification step, which reduces the use of chemicals. Our study provides a nontoxic and inexpensive immobilization strategy for the biocatalytic reaction in food industry.


Assuntos
Enzimas Imobilizadas/química , Enzimas Imobilizadas/isolamento & purificação , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Biocatálise , Enzimas Imobilizadas/metabolismo , Glicosídeo Hidrolases/metabolismo , Ligações de Hidrogênio , beta-Glucanas/química
4.
Food Chem ; 298: 124999, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261010

RESUMO

Glycoside hydrolase family 8 (GH8) includes endoglucanases, lichenases, chitosanases and xylanases, which are essential for polysaccharides breakdown. In this work, we studied a thermally stable GH8 from the cellulose synthase complex of Enterobacter sp. R1, for deconstruction of ß-glucans. The biochemical characterization of the recombinant GH8ErCel showed high specificity towards barley ß-glucan and lichenan and lower activity on carboxymethylcellulose and swollen cellulose, yielding different length oligosaccharides. By molecular modeling, six conserved subsites for glucose binding and some possible determinants for its lack of xylanase and chitosanase activity were identified. GH8ErCel was active at a broad range of pH and temperature and presented remarkable stability at 60 °C. Additionally, it hydrolyzed ß-glucan from oat and wheat brans mainly to tri- and tetraoligosaccharides. Therefore, GH8ErCel may be a good candidate for enzymatic deconstruction of ß-glucans at high temperature in food and feed industries, including the production of prebiotics and functional foods.


Assuntos
Celulase/química , Celulase/metabolismo , Celulose/metabolismo , Enterobacter/enzimologia , beta-Glucanas/metabolismo , Argentina , Carboximetilcelulose Sódica/metabolismo , Celulase/genética , Enterobacter/genética , Enterobacter/isolamento & purificação , Estabilidade Enzimática , Glucanos/metabolismo , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Oligossacarídeos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Microbiologia do Solo , Especificidade por Substrato , Temperatura Ambiente , beta-Glucanas/química
5.
J Agric Food Chem ; 67(32): 9070-9078, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31343168

RESUMO

In this study, an immunologically active novel microparticulate mushroom ß-glucan (PRA-1p) was prepared using an alkali-soluble glucan PRA-1 by an emulsification and cross-linking method. PRA-1 was a hyperbranched (1→3),(1→6)-ß-d-glucan with a degree of branching of 0.89, isolated from the sclerotia of Polyporus rhinocerus. PRA-1 had a rod-like conformation, while PRA-1p exhibited a monodisperse and homogeneous spherical conformation with a diameter ranging from 0.3 to 2.0 µm in water. PRA-1p significantly induced nitric oxide and reactive oxygen species production as well as morphological changes of murine macrophages (RAW 264.7 cells) and upregulated their phagocytic activity. Furthermore, PRA-1p treatment markedly enhanced the secretion of cytokines, including cutaneous T cell-attracting chemokine 27, granulocyte-colony-stimulating factor, monocyte chemoattractant protein 1, macrophage inflammatory protein 1α, macrophage inflammatory protein 2, regulated on activation, normal T cell expressed and secreted, soluble tumor necrosis factor receptor 1, and tissue inhibitors of metalloproteinases. Activation of RAW 264.7 cells triggered by PRA-1p was associated with activation of inducible nitric oxide synthase, nuclear factor κB, extracellular signal-regulated kinase, and protein kinase B. This work suggests that novel PRA-1p derived from the mushroom sclerotia of P. rhinocerus has potential application as an immunostimulatory agent.


Assuntos
Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polyporus/química , beta-Glucanas/química , beta-Glucanas/farmacologia , Animais , Quimiocina CCL27/genética , Quimiocina CCL27/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Fatores Imunológicos/isolamento & purificação , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , NF-kappa B/genética , NF-kappa B/imunologia , Óxido Nítrico/imunologia , Fagocitose/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Polyporus/imunologia , Células RAW 264.7 , Espécies Reativas de Oxigênio/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , beta-Glucanas/isolamento & purificação
6.
Food Chem ; 297: 124953, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253297

RESUMO

The present study investigated the effects of proteins, lipids and ß-glucan in naked oat flour (NOF) on the in vitro digestibility of starch. The content of rapidly digested starch (RDS) increased, and the content of resistant starch (RS) decreased in NOF after removing the non-starch constituents. The estimated glycemic index (eGI) of starch in NOF increased after the removal of the non-starch constituents, with a decreasing order of naked oat starch (NOS) > de-ß-glucan flour > de-proteins flour > de-lipids flour > NOF. NOS was found to have an A-type crystalline pattern, but the removal of proteins or ß-glucan rendered NOS a V-type crystalline pattern. The relative crystallinity decreased after removing non-starch constituents. The in vitro digestibility was positively correlated with the short-range molecular order and negatively correlated with the relative crystallinity. These results clearly illustrate the effects of non-starch constituents on the low digestibility of naked oat.


Assuntos
Avena/química , Amido/química , Amido/farmacocinética , Digestão , Farinha , Índice Glicêmico , Lipídeos/química , Lipídeos/farmacocinética , Proteínas de Vegetais Comestíveis/química , Proteínas de Vegetais Comestíveis/farmacocinética , Solubilidade , beta-Glucanas/química , beta-Glucanas/farmacocinética
7.
Carbohydr Polym ; 219: 1-11, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151505

RESUMO

Wastewater treatment materials that combine high decontamination performance, ease of use and economic production are highly desirable for practical applications. Herein, we fabricated a low-cost and recyclable bio-adsorbent based on a microbial polysaccharide (salecan) for efficient removal of methyl violet (MV) from wastewater. The success fabrication and the properties (such as thermal stability, microarchitecture, mechanical strength and water uptake) of the adsorbent had been investigated, and the hydrogels were found to have tunable properties by simple adjusting the salecan dose in hydrogel composition. Adsorption data displayed that the adsorption of MV followed the pseudo second-order kinetic model (R2 = 0.99015) and Freundlich isotherm model (R2 = 0.99221) with a maximum adsorption capacity of 178.9 mg/g. Moreover, salecan-based hydrogels showed a good reversibility in adsorption-desorption cycles. These features indicate that salecan-based bio-adsorbent may be a promising device for dye removal from dyeing waste water.


Assuntos
Descontaminação/métodos , Violeta Genciana/química , Hidrogéis/química , Polissacarídeos Bacterianos/química , Purificação da Água/métodos , beta-Glucanas/química , Corantes/química , Cinética , Águas Residuárias/toxicidade , Poluentes Químicos da Água/química
8.
J Agric Food Chem ; 67(26): 7416-7427, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31180666

RESUMO

The core-shell structured micelles from octenylsuccinated oat ß-glucan (OSßG) are able to solubilize ß-carotene (ßC). This study reveals molecular interactions governing the formation, stabilization, and ßC uptake of OSßG micelles (OSßG-Ms) by means such as water contact angle, 1H nuclear magnetic resonance, dynamic light scattering, and confocal laser scanning microscopy. The results indicated that the micellization of OSßG molecules is triggered by hydrophobic interactions between octenylsuccinate (OSA) moieties, while OSßG-Ms are stabilized via both hydrophobic interactions and hydrogen bonds. For their uptake of ßC, ßC molecules are first adsorbed onto OSßG-Ms by interacting with OSA moieties scattered on micelle surface. By further interacting with OSA moieties located in micelle shell, ßC molecules travel across the shell and finally are trapped in the hydrophobic core. In simulated gastrointestinal fluids, ßC is controlled released from OSßG-Ms as an integrated consequence of its diffusion as well as the swelling and erosion of OSßG-Ms. As a result, this study first uncovered the mechanism underlying the uptake of ßC by OSßG-Ms, which will certainly facilitate the effective loading of hydrophobic ingredients by OSßG-Ms.


Assuntos
Avena/química , Preparações de Ação Retardada/química , Extratos Vegetais/química , Succinatos/química , beta Caroteno/química , beta-Glucanas/química , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Micelas , Estrutura Molecular
9.
Plant Foods Hum Nutr ; 74(3): 334-341, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31175546

RESUMO

The aim of the study was to investigate the potential of using ß-glucan as wall material to microencapsulate the elderberry extract. Firstly, the extract was obtained by the water-acetone extraction method to extract mainly anthocyanins from ground dried fruits. The extract was mixed with wall materials: maltodextrin-ß-glucan mixture and the control sample as a widely used combination of maltodextrin and arabic gum (92.5:7.5). In the examined samples the content of ß-glucan was 0.5, 1, 2 and 3%. Properties of encapsulated extracts of final powders were measured using particle size and morphology, encapsulation efficiency, color measurement, total anthocyanin and ascorbic acid content (TAC and TAAC) methods. Our results indicated that the ß-glucan wall material samples had higher process quality compared to control samples. Addition of ß-glucan insignificantly decreases encapsulation efficiency. Among powders with ß-glucan content, the powder with 1% ß-glucan content was characterized by the smallest (24 µm) particle size. The sample with 2% ß-glucan content had the highest water solubility and polydispersity index. Due to the encapsulation efficiency, moisture content, and water solubility index, the optimum condition of microencapsulation process for elderberry extract was for samples with 0.5% ß-glucan as wall material content. To conclude, due to high molecular weight of ß-glucan the higher than 0.5% ratio of ß-glucan is not recommended for spray-drying method. However, small quantity of health-beneficial ß-glucan could act as potential encapsulation agent in clean label products to replace Arabic gum.


Assuntos
Antocianinas/análise , Ácido Ascórbico/análise , Composição de Medicamentos/métodos , Extratos Vegetais/química , Sambucus nigra/química , beta-Glucanas/química , Dessecação , Frutas/química , Goma Arábica/química , Tamanho da Partícula , Polissacarídeos/química , Pós , Solubilidade , Água/química
10.
Molecules ; 24(9)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058866

RESUMO

Background: Wet methods of 1-3, 1-4 -ß-D-glucan isolation from cereals differ mainly in the type of grain fraction used as raw material, the solid-liquid ratio of ß-glucan in raw material vs. solvent used, and the type of aqueous solvent modification (alkali, neutral or acidic). All these factors impact the characterization of the residues finally found in extracts. Oat bran is a rich source of globulin fraction which can be transferred into the extracts, especially when a high pH is employed. Methods: A multi-stage (enzymatic and acidic) purification procedure was performed to remove the residues, especially starch and protein, from ß-glucan isolates from oat of different molar mass. Pancreatin, thermostable α-amylase, amyloglucosidase, and papain were used for consecutive residue removal. Three levels of low pH = 4.5, 3.5 and 3.0 were also tested for effective protein precipitation. Results: The starch hydrolysis and liquefaction significantly facilitate the proteinaceous matter removal although papain usage showed an intensive unfavorable impact on ß-glucan molar mass. Soluble protein content was significantly decreased after pancreatin and α-amylase treatment, while the significant reduction of amine nitrogen was noted after complete starch hydrolysis and a second acidification step. Conclusions: A complex procedure employing different enzymes is needed to successfully reduce the possibly bioactive residues in isolated oat ß-glucan fractions.


Assuntos
Enzimas/metabolismo , Globulinas/isolamento & purificação , Amido/isolamento & purificação , beta-Glucanas/química , Avena , Precipitação Fracionada , Globulinas/química , Concentração de Íons de Hidrogênio , Hidrólise , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Solventes/química , Amido/química , Viscosidade , beta-Glucanas/isolamento & purificação
11.
J Agric Food Chem ; 67(24): 6847-6855, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31132258

RESUMO

Chitooligosaccharide has been reported to possess diverse bioactivities. The development of novel strategies for obtaining optimum degree of polymerization (DP) chitooligosaccharides has become increasingly important. In this study, two glycoside hydrolase family 46 chitosanases were studied for immobilization on curdlan (insoluble ß-1,3-glucan) using a novel carbohydrate binding module (CBM) family 56 domain from a ß-1,3-glucanase. The CBM56 domain provided a spontaneous and specific sorption of the fusion proteins onto a curdlan carrier, and two fusion enzymes showed increased enzyme stability in comparison with native enzymes. Furthermore, a continuous packed-bed reactor was constructed with chitosanase immobilized on a curdlan carrier to control the enzymatic hydrolysis of chitosan. Three chitooligosaccharide products with different molecular weights were prepared in optimized reaction conditions. This study provides a novel CBM tag for the stabilization and immobilization of enzymes. The controllable hydrolysis strategy offers potential for the industrial-scale preparation of chitooligosaccharides with different desired DPs.


Assuntos
Proteínas de Bactérias/química , Glicosídeo Hidrolases/química , Oligossacarídeos/química , Paenibacillus/enzimologia , Biocatálise , Carboidratos/química , Estabilidade Enzimática , Enzimas Imobilizadas/química , Família Multigênica , Paenibacillus/química , Domínios Proteicos , beta-Glucanas/química
12.
J Agric Food Chem ; 67(22): 6324-6335, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31083935

RESUMO

This study was conducted to evaluate the effect of growth conditions and genotype on the barley yield and ß-glucan content of grain and malt. Total and water-extractable (W-E) ß-glucans and their molecular and structural properties were analyzed in nine 2-row barley varieties and corresponding malts. The total ß-glucan content of barley is not influenced by year or by the cultivar, while the grain yield and W-E ß-glucan content are significantly influenced by the year. Barley W-E ß-glucans have a molecular weight between 1.0 × 105 and 4.0 × 105 Da and a random coil conformation. ß-Glucan levels in malt are significantly lower than in barley, and neither the total nor the W-E ß-glucans are influenced by environmental factors or genetic aspects. W-E ß-glucans are mainly composed of fractions with Mw values below 1.0 × 105 Da. In conclusion, the molecular characterization of ß-glucans could represent a powerful tool to understand their role in the brewing process.


Assuntos
Hordeum/crescimento & desenvolvimento , beta-Glucanas/química , Manipulação de Alimentos , Genótipo , Hordeum/química , Hordeum/genética , Hordeum/metabolismo , Sementes/química , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , beta-Glucanas/metabolismo
13.
Carbohydr Polym ; 217: 135-143, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079669

RESUMO

The parameters to extract polysaccharide-enriched fractions (PEF) from mushrooms using MAE (microwave-assisted extraction) were adjusted following a full factorial 32 experimental design. The highest yield and total carbohydrate values, using Lentinula edodes as model mushroom, were obtained at 180 °C and 30 min. Several mushroom species were submitted to MAE and their PEF yields ranged between 12.1-44.2%. (1→3)-ß-Glucans determination using a conventional fluorimetric method changed depending on the standard utilized. NMR analyses of PEF indicated that the presence of other polysaccharides in the extracts or their specific folding, might impair the proper determination of (1→3) linkages by the fluorophore. Mushrooms from Cantharellales order contained (1→3)-ß-glucans but they were not detected with the fluorimetric method. Therefore, although the method (after adjustments) was sensitive enough to detect their presence in many mushroom extracts, it cannot be used for all species and it is also not recommended for quantitative determinations.


Assuntos
Agaricales/química , Compostos de Anilina/química , Corantes Fluorescentes/química , Extração em Fase Sólida/métodos , beta-Glucanas/isolamento & purificação , Benzenossulfonatos/química , Fluorometria/métodos , Carpóforos/química , Micro-Ondas , beta-Glucanas/química
14.
Int J Mol Sci ; 20(9)2019 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-31083511

RESUMO

Exocellular (1→6)-ß-d-glucan (lasiodiplodan) produced by the fungus Lasiodiplodia theobromae MMPI was derivatized by carboxymethylation using different concentrations of a derivatizing agent. Lasiodiplodan was derivatized by carboxymethylation in an attempt to increase its solubility and enhance its biological activities. Carboxymethylglucans with degrees of substitution (DS) of 0.32, 0.47, 0.51, 0.58, and 0.68 were produced and characterized. FTIR analysis showed a band of strong intensity at 1600 cm-1 and an absorption band at 1421 cm-1, resulting from asymmetric and symmetrical stretching vibrations, respectively, of the carboxymethyl group COO- in the carboxymethylated samples. Thermal analysis showed that native lasiodiplodan (LN) and carboxymethylated derivatives (LC) exhibited thermal stability up to 200-210 °C. X-ray diffractometry demonstrated that both native and carboxymethylated lasiodiplodan presented predominantly an amorphous nature. Scanning electron microscopy revealed that carboxymethylation promoted morphological changes in the biopolymer and increased porosity, and alveolar structures were observed along the surface. The introduction of carboxymethyl groups in the macromolecule promoted increased solubility and potentiated the hydroxyl radical-scavenging activity, suggesting a correlation between degree of substitution and antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Ascomicetos/química , beta-Glucanas/metabolismo , beta-Glucanas/farmacologia , Depuradores de Radicais Livres/química , Metilação , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Termogravimetria , Difração de Raios X , beta-Glucanas/química
15.
Int J Biol Macromol ; 132: 236-243, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30930267

RESUMO

The oil-in-water emulsion system is very common in food production. The aim of this study was the evaluation of extracted (enzymatic treatment) cereal ß-glucan as a stabiliser in comparison to other commonly used food additives. Oat (OBG) and barley (BBG) ß-glucan were applied at concentrations of 1%, 2% and 4%; gum guar, xanthan gum, hydroxypropyl methylcellulose at 0.5% each; lecithin at 2%; polyglycerol polyricinoleate at 4%; and, finally pectin at 3.2%. The following physical properties were examined: emulsion stability, foaming capacity and stability, droplet size distribution and viscosity. The results showed that cereal ß-glucan reached very good emulsion stability (>80% after 14 days) and relatively high values of apparent viscosity (up to 12,243 cPa·s for 4% OBG, and 2264 cPa·s for 4% BBG; γ̇=20 1/s, day 14). The droplet size of barley ß-glucan emulsion ranged between 14.88 and 60.06 µm, and of oat ß-glucan emulsion between 15.68 and 46.22 µm. The results showed that cereal ß-glucan acts like a viscosifier and can be applied in a variety of food products to improve their texture and viscosity.


Assuntos
Grão Comestível/química , Óleos/química , Água/química , beta-Glucanas/química , Avena/química , Estabilidade de Medicamentos , Emulsões , Hordeum/química , Peso Molecular , Viscosidade
16.
J Food Sci ; 84(5): 1068-1077, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30990884

RESUMO

The influence of different addition levels (0.1% to 0.5%) of thermo-reversible curdlan gels (TRC) and thermo-irreversible curdlan gels (TIRC) on the physicochemical and textural characteristics of frankfurters, as well as dynamic rheological properties of meat batters, was investigated. Increased percentages of TRC and TIRC were associated with lower cooking loss and quicker relaxation times, as well as superior emulsion stability, and higher L* -values and b* -values of frankfurters (P < 0.05). Moreover, with equal curdlan concentrations from 0.3% to 0.5%, TRC showed higher hardness and chewiness values than those with added TIRC (P < 0.05), but the gumminess, springiness, and resilience values were almost the same between each treatment (P > 0.05). The textural profile results were in strong agreement with the rheological data. Principal component analysis revealed that certain quality attributes were affected differently by the inclusion levels of TRC and TIRC. Additionally, the distinctive mechanism of the formation of the complex meat protein network by TRC or TIRC was also clarified and verified via scanning electron microscopy analysis. Further studies will investigate the molecular interactions of meat proteins with these two types of curdlan gels as a function of addition levels. PRACTICAL APPLICATION: Curdlan can form two different types of gels mainly depending on heating temperature, designated as thermo-reversible curdlan gels (TRC) and thermo-irreversible curdlan gels (TIRC), respectively. The addition of these two gels could improve the textural and gel properties of frankfurters, as well as improve the rheological profiles of meat batters. Each gel type invokes a different mechanism of influence on the formation of the complex meat protein network. Results indicate that TRC (mainly as an effective gelling agent) and TIRC (mainly as a potential fat-mimetic) can provide distinctive frankfurter formulations catered to the requirements preferred by different consumers.


Assuntos
Géis/química , Produtos da Carne/análise , beta-Glucanas/química , Culinária , Emulsões , Reologia
17.
Chem Asian J ; 14(12): 2102-2107, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-30997743

RESUMO

The semi-artificial branched-polysaccharides, amylose-grafted curdlans, were synthesized utilizing an enzymatic polymerization. Both a curdlan main chain and amylose side chains on the polysaccharides maintain the original helical structure as well as the molecular binding ability. Thanks to the difference in their molecular recognition properties between ß-1,3-glucan chain and α-1,4-glucan chain, the amylose-grafted curdlans can provide two different orthogonal binding sites within one polymeric system. When a water-soluble polythiophene was mixed with the amylose-grafted curdlan, the polythiophene was twisted in two different modes and therein, fluorescence energy of the polythiophene wrapped by the amylose side chains was successfully transferred to the polythiophene wrapped by the curdlan main chain. We thus concluded that in the dendritic superstructure of this polysaccharide, a self-organized "Janus-type FRET system" was successfully constructed.


Assuntos
Amilose/química , beta-Glucanas/química , beta-Glucanas/síntese química , Sítios de Ligação , Transferência Ressonante de Energia de Fluorescência , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Polimerização
18.
Poult Sci ; 98(8): 3326-3337, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30941405

RESUMO

ß-glucans are cereal-derived soluble fiber compounds that elicit health benefits when consumed in amounts of 0.75 g/serving. The use of ß-glucans in whole muscle meat products, such as chicken breast, is unexplored and needs clarification at a discovery level. The objective of this study was to evaluate the incorporation of ß-glucan in the whole muscle chicken breast and identify changes in physical, chemical, textural, microbiological, and thermal properties during 9 D of aerobic storage at refrigeration temperatures. Treatments were 1) control (no salt or ß-glucan added; CON), 2) salt solution (2% NaCl and 0.2% phosphate curing solution; SALT), 3) ß-glucan solution (1.5% ß-glucan; ßG), and 4) combination of salt and ß-glucan solutions (2% NaCl, 0.2% phosphate, and 1.5% ß-glucan; SALT+ßG). The target injection level was 20%, however the average uptake level was 8.15%. Color, pH, shear force, and bacteria count were minimally affected by treatment during the 9 D of aerobic storage at 4°C. Cooking loss (P < 0.01) was greater in CON samples compared to all other treatments indicating the presence of salt or fiber or both improved water retention. The ß-glucan concentration in uncooked chicken following injection was 0.125 g/100 g product and 0.133 g/100g product in ßG and SALT+ßG treatments, respectively. Following cooking, the ß-glucan concentration was 0.010 g/100g product and 0.004 g/100g product in ßG and SALT+ßG treatments, respectively. There was no storage day effect (P = 0.42) for the ß-glucan concentration in cooked product, therefore it was assumed that during cooking, ß-glucan concentration in whole muscle injected products was lost. Finally, thermal behavior measured with a differential scanning calorimeter indicated that there were only minimal differences, although some significant, among treatments in this study. Overall, the application of ß-glucan injection in whole chicken breast was not detrimental to product quality and actually improved water retention levels. However, new methods need to be developed for the incorporation of ß-glucan in injected whole muscle meat product so that ß-glucan can be retained during and after cooking.


Assuntos
Armazenamento de Alimentos , Produtos Avícolas/análise , beta-Glucanas/química , Animais , Galinhas , Cor , Culinária , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Músculos Peitorais , Polifosfatos/química , Produtos Avícolas/microbiologia , Resistência ao Cisalhamento , Cloreto de Sódio/química
19.
Food Chem ; 291: 180-186, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31006457

RESUMO

In this study, a positively charged quaternized curdlan (Qcurd) was used to fabricate polyelectrolyte complex nanoparticles (PEC NPs) with a negatively charged pectin via electrostatic complexation. Results showed that the Qcurd/pectin PEC NPs prepared with 0.5 mg/mL Qcurd and pectin solutions, 1:2 pectin/Qcurd mass ratio, and pH 4.0 in the absence of NaCl were characterized by a spherical morphology in nanoscale, an average particle size of 68 nm, and good dispersibility in aqueous solutions. Curcumin was encapsulated in the Qcurd/pectin PEC NPs through hydrogen bonding with an encapsulation efficiency of ∼82%, a loading content of 13%, and a pH-dependent controlled release. Curcumin-loaded PEC NPs exhibited a significantly enhanced water solubility, excellent free radical scavenging ability and antioxidant capacity in vitro as compared with those of free curcumin.


Assuntos
Materiais Biocompatíveis/química , Curcumina/química , Nanopartículas/química , Pectinas/química , Polieletrólitos/química , beta-Glucanas/química , Portadores de Fármacos/química , Tamanho da Partícula , Solubilidade
20.
Molecules ; 24(8)2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022848

RESUMO

The purpose of this study is to develop a robust approach to obtain ß glucans from Lentinus edodes and to characterize their structural and biological properties for sustainable utilization. The alkali extraction was optimized with an orthogonal experimental design, and a concise process for obtaining specific targeting polysaccharides from Lentinus edodes was developed in this study. After purification with a Q-Sepharose Fast Flow strong anion-exchange column, the monosaccharide composition, a methylation analysis, and NMR spectroscopy were employed for their structural characterizations. LeP-N2 was found to be composed of (1→6)-ß-d-glucans with minor ß-(1→3) glucosidic side chains. Atomic force microscopy (AFM) and high-performance gel permeation chromatography-refractive index-multi-angle laser light scattering (HPGPC-RI-MALLS) also revealed LeP-N2 exhibiting a compact unit in aqueous solution. This (1→6)-ß-d-glucan was tested for antioxidant activities with IC50 at 157 µg/mL. Moreover, RAW 264.7 macrophage activation indicated that the release of nitric oxide (NO) and reactive oxygen species (ROS) was markedly increased with no cytotoxicity at a dose of 100 µg/mL. These findings suggest that the (1→6)-ß-d-glucans obtained from Lentinus edodes could serve as potential agents in the fields of functional foods or medicine.


Assuntos
Antioxidantes/química , Polissacarídeos/química , Cogumelos Shiitake/química , beta-Glucanas/química , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Cromatografia em Gel , Espectroscopia de Ressonância Magnética , Camundongos , Microscopia de Força Atômica , Estrutura Molecular , Polissacarídeos/isolamento & purificação , Células RAW 264.7 , Espécies Reativas de Oxigênio/química , Água/química , beta-Glucanas/isolamento & purificação , beta-Glucanas/farmacologia
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