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1.
Carbohydr Polym ; 260: 117711, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712120

RESUMO

The metabolites produced by plants can be enhanced by plant tissue culture. In Premma puberula Pamp., the pectin content in leaves is 30 %-40 %, and it is widely used in the food industry and medicine. However, inefficient propagation has seriously restricted the utilization of pectin resources. Therefore, we established an efficient micropropagation technology for P. puberula through comparative analysis in mature leaves of regenerated and conventionally propagated plants. The results showed that the pectin composition of their leaves was similar in terms of galacturonic acid, monosaccharide composition, degree of esterification, functional groups, nuclear magnetic resonance spectrum and morphological characteristics. Furthermore, micropropagated plants had better hardness, gumminess and chewiness characteristics than conventionally propagated plants and were similar in emulsion stability, adhesiveness, springiness, cohesiveness and viscoelasticity. Therefore, micropropagation technology will provide an important guarantee for the industrial production of pectin from P. puberula. The technical essentials include callus induction, embryoid formation, and root induction, followed by acclimatization and transplanting.


Assuntos
Lamiaceae/metabolismo , Pectinas/metabolismo , Emulsificantes/química , Esterificação , Ácidos Hexurônicos/análise , Lamiaceae/citologia , Monossacarídeos/análise , Pectinas/química , Pectinas/isolamento & purificação , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Viscosidade
2.
Nat Commun ; 12(1): 1201, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33619275

RESUMO

Glycolipids are complex glycoconjugates composed of a glycan headgroup and a lipid moiety. Their modular biosynthesis creates a vast amount of diverse and often isomeric structures, which fulfill highly specific biological functions. To date, no gold-standard analytical technique can provide a comprehensive structural elucidation of complex glycolipids, and insufficient tools for isomer distinction can lead to wrong assignments. Herein we use cryogenic gas-phase infrared spectroscopy to systematically investigate different kinds of isomerism in immunologically relevant glycolipids. We show that all structural features, including isomeric glycan headgroups, anomeric configurations and different lipid moieties, can be unambiguously resolved by diagnostic spectroscopic fingerprints in a narrow spectral range. The results allow for the characterization of isomeric glycolipid mixtures and biological applications.


Assuntos
Temperatura Baixa , Glicolipídeos/química , Galactosilceramidas/química , Monossacarídeos/análise , Espectrofotometria Infravermelho , Esfingosina/química , Estereoisomerismo
3.
J Food Sci ; 86(2): 306-318, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33462808

RESUMO

In this study, response surface methodology was employed to optimize the ultrasound-assisted extraction (UAE) process of perilla seed meal polysaccharides (PSMP). The optimal conditions for UAE of PSMP were: liquid-solid ratio of 26.00 mL/g, ultrasonic temperature of 43.00 °C, ultrasonic time of 52.00 min, and ultrasonic power of 229.00 W, the optimal conditions lead to an yield of 6.137 ± 0.062%. The structural characteristics of molecular weight, compositional monosaccharides, and glycosidic linkages were determined by size exclusion chromatography with multiangle light scattering, gas chromatography-mass spectrometry, Fourier-transfer infrared spectroscopy, and nuclear magnetic resonance detections. Scanning electron microscopy analysis showed that many holes were formed on the surface of PSM after UAE. The antioxidant activities of PSMP were investigated using various assays in vitro. The results suggested that PSMP is potential natural resource of antioxidants for medicine and functional foods. PRACTICAL APPLICATION: The selection of raw material perilla seed meal is conducive to the comprehensive utilization of edible resources. With consumer demands for newly developed foods with natural, wholesome ingredients are increasing nowadays. This study provides effective reference for in-depth research on other medicine-food dual-use resources. Ultrasound-assisted extraction (UAE) is a promising alternative method for hot water reflux extraction (HWRE) of polysaccharides for advantages of high efficiency and energy saving. In this work, the UAE process optimized by response surface methodology is more suitable for industrial application that can effectively decrease total cost of production by reducing the extraction temperature, shortening extraction time, and increasing raw material utilization.


Assuntos
Antioxidantes , Perilla/química , Polissacarídeos/isolamento & purificação , Sementes/química , Ondas Ultrassônicas , Antioxidantes/análise , Glicosídeos/química , Peso Molecular , Monossacarídeos/análise , Polissacarídeos/química , Temperatura
4.
Carbohydr Polym ; 251: 117080, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142623

RESUMO

A water-soluble ß-glucan from fruiting body of Hericium erinaceus was obtained after water extraction, purification and fractionation. Analyses of monosaccharide composition, molecular weight and linkage mode demonstrated that it is a ß-glucan with 1→3 and 1→6 linkage modes and a molecular weight of 13.3 kDa. An endo-1,6-ß-d-glucanase was used to digest the ß-glucan and the digested products over time were analyzed with a HPAEC-PAD-MS platform. The linkage mode of each glycosidic bond in the digested oligosaccharides were confirmed with MS/MS. At the end of digestion, enzyme resistant oligosaccharides were observed as several 1→6 linked glucoses with one or two 1→3 linked glucose residues. All these domains are more like constructional pieces from a branch-on-branch glucan, in which multiple 1→6 linked glucan chains are hooked through one or two 1→3 linked glucose residues. Averagely, there is a 1→3 linkage per six 1→6 linked glucoses in this branch-on-branch ß-glucan.


Assuntos
Carpóforos/química , Monossacarídeos/análise , Oligossacarídeos/química , Espectrometria de Massas em Tandem/métodos , beta-Glucanas/química , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Peso Molecular
5.
Food Chem ; 335: 127522, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32739804

RESUMO

Effect of twin-screw extrusion on soluble dietary fiber (SDF) from sweet potato residues (SPRs) were investigated using optimized conditions, at screw speed of 180 rpm, feed rate at 17 Hz, feed moisture at 40% and extrusion temperature at 150 °C. Extruded SDF, showed higher SDF levels (9.63%-29.25%), cholesterol and sodiumcholate adsorption capacity, radical scavenging capacity, and inhibition of digestive enzymes. Moreover, extrusion effectively reduced particle size and molecularweight of SDF, modulated monosaccharide ratios, and increased water retention capacity (WRC), oil retention capacity (ORC), swelling capacity (SC) and glucose absorption capacity (GAC). Additionally, scanning electron microscopy (SEM) demonstrated decomposition of macromolecules of SDF to smaller fractions and formation of a porous morphology following extrusion. Furthermore, the extruded SDF increased thermal stability as determined by differential scanning calorimetry (DSC). Overall, the SDF from SPRs with improved functional and physiochemical properties could be used as a functional additive in diverse food products.


Assuntos
Fibras na Dieta/análise , Ipomoea batatas/química , Peso Molecular , Monossacarídeos/análise , Solubilidade , Temperatura
6.
Food Chem ; 339: 128064, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950902

RESUMO

Ultrasonic degradation has become a fascinating strategy for preparing modified pectin, contributing to the improvement of pectin's functional characteristics. In this study, the impacts of structural and conformational characteristics of original and ultrasound-treated citrus pectins on their functional properties were examined. The results showed that compared with ultrasound-treated pectins, untreated pectin presented higher rheological and gelling properties primarily attributed to its larger weight-average molecular weight (Mw), degree of methoxylation, amount of neutral sugar side chains, and z-average radius of gyration, as well as the more extended flexible-chain conformation. However, the ultrasound-treated pectins had better emulsifying properties than untreated pectin in an oil-in-water emulsion system. These properties, visually suggested by morphology analysis, including enhanced emulsifying capacity, emulsifying stability, reduced mean droplet size and negatively charged zeta potential. Moreover, the Mw and chain conformation of untreated and ultrasound-treated pectins played more decisive roles in their functional properties than the others.


Assuntos
Emulsificantes/química , Pectinas/química , Configuração de Carboidratos , Conformação Molecular , Peso Molecular , Monossacarídeos/análise , Reologia , Açúcares , Ultrassom
7.
PLoS One ; 15(7): e0236190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32702068

RESUMO

The quality of sourdough bread mainly depends on metabolic activities of lactic acid bacteria (LAB). The exopolysaccharides (EPS) produced by LAB affect positively the technological and nutritional properties of the bread, while phytases improve the bioavailability of the minerals by reducing its phytate content. In the present study, a pool of 152 cereal-sourced LAB were screened for production of phytases and EPS for potential use as sourdough starter cultures for the baking industry. There was large heterogeneity in the phytase activity observed among the screened isolates, with 95% showing the ability to degrade sodium phytate on plates containing Sourdough Simulation Medium (SSM). The isolates Lactobacillus brevis LD65 and Lactobacillus plantarum PB241 showed the highest enzymatic activity, while the isolates ascribed to Weissella confusa were characterized by low or no phytase activity. Only 18% of the screened LAB produced EPS, which were distinguished as ropy or mucoid phenotypes on SSM supplemented with sucrose. Almost all the EPS producers carried one or more genes (epsD/E and/or epsA) involved in the production of heteropolysaccharides (HePS), whereas the isolates ascribed to Leuconostoc citreum and W. confusa carried genes involved in the production of both HePS and homopolysaccharides (HoPS). Monosaccharide composition analysis of the EPS produced by a selected subset of isolates revealed that all the HePS included glucose, mannose, and galactose, though at different ratios. Furthermore, a few isolates ascribed to L. citreum and W. confusa and carrying the gtf gene produced ß-glucans after fermentation in an ad hoc formulated barley flour medium. Based on the overall results collected, a subset of candidate sourdough starter cultures for the baking industry was selected, including Lb. brevis LD66 and L. citreum PB220, which showed high phytase activity and positive EPS production.


Assuntos
Pão/microbiologia , Grão Comestível/microbiologia , Microbiologia de Alimentos , Indústrias , Lactobacillales/isolamento & purificação , 6-Fitase/metabolismo , Fermentação , Farinha , Genes Bacterianos , Hordeum , Lactobacillales/genética , Peso Molecular , Monossacarídeos/análise , Polissacarídeos Bacterianos/metabolismo , RNA Ribossômico 16S/genética , Especificidade da Espécie , beta-Glucanas/análise
8.
Food Chem ; 331: 127340, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32569971

RESUMO

Acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted and purified from the cartilages of skate and sturgeon. Their typical structure and physicochemical properties were evaluated by circular dichroism (CD), X-ray diffraction (XRD), and so on. Results showed that the extracted collagen was likely identified as collagen-II composed of three α-chains (135 kDa), with the typical peptide sequence of Gly-X-Y. It showed the collagen retained the native and intact triple helical structure, and its intensity ratio of the positive and negative absorption peaks (Rpn) was 0.19-0.25. In addition, the extracted collagen exhibited obvious self-assembly behavior with the concentration above 0.3 mg/mL, the adjustment of pH 7.4-7.6 and the NaCl concentration of 120 mmol/L. The critical aggregate mass concentrations of pepsin-soluble collagens from skate and sturgeon were 0.93 and 0.86 g/L, respectively. Therefore, collagens from skate and sturgeon cartilages have potential commercial application.


Assuntos
Cartilagem/química , Colágeno Tipo II/química , Proteínas de Peixes/química , Peixes , Aminoácidos/análise , Animais , Dicroísmo Circular , Colágeno Tipo II/análise , Produtos Pesqueiros , Proteínas de Peixes/análise , Concentração de Íons de Hidrogênio , Monossacarídeos/análise , Concentração Osmolar , Pepsina A/química , Conformação Proteica , Rajidae , Cloreto de Sódio/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
J Biosci Bioeng ; 130(3): 283-289, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32507385

RESUMO

A novel exopolysaccharide (EPS) from Paenibacillus polymyxa PYQ1 was extracted, well purified and characterized. This EPS was homogeneous glucomannan-type polysaccharide with the average molecular weight of 4.38 × 106 Da. Structural characterization indicated that the monosaccharides of EPS were pyranoses connected by ß-glycosidic linkages. Furthermore, our results showed the protective benefits of EPS against UVC induced cytotoxicity in HaCaT cells through scavenging excessive reactive oxygen species, mitigating the decrease of mitochondrial membrane potential, improving catalase activity and maintaining membrane integrity. Taken together, this study qualified EPS from P. polymyxa PYQ1 was a promising natural polymer which worth further investigation as a skin-care agent.


Assuntos
Citoproteção/efeitos dos fármacos , Paenibacillus polymyxa/metabolismo , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/farmacologia , Raios Ultravioleta/efeitos adversos , Catalase/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Peso Molecular , Monossacarídeos/análise , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/química , Espécies Reativas de Oxigênio/metabolismo
10.
Int J Food Microbiol ; 326: 108648, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32387971

RESUMO

Consumption of fructan-containing cereal products is considered beneficial for most people, but not for those suffering from irritable bowel syndrome (IBS), as they should avoid the consumption of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (acronym: FODMAP). Controlling fructan levels in cereal products is not trivial. However, controlling yeast invertase-mediated hydrolysis of fructan during dough fermentation might offer a handle to modulate fructan concentrations. In this work, the variability in invertase activity and substrate specificity in an extensive set of industrial Saccharomyces cerevisiae strains is investigated. Analysis showed a high variability in the capacity of these strains to hydrolyse sucrose and fructo-oligosaccharides. Industrial yeast strains with a high activity towards fructo-oligosaccharides efficiently reduced wheat grain fructans during dough fermentation to a final fructan level of 0.3% dm, whereas strains with a low invertase activity yielded fructan levels around 0.6% dm. The non-bakery strains produced lower levels of CO2 in fermenting dough resulting in lower loaf volumes. However, CO2 production and loaf volume could be increased by the addition of 3% glucose. In conclusion, this study shows that variation in yeast invertase activity and specificity can be used to modulate the fructan content in bread, allowing the production of low FODMAP breads, or alternatively, breads with a higher soluble dietary fibre content.


Assuntos
Dissacarídeos/análise , Monossacarídeos/análise , Oligossacarídeos/análise , Saccharomyces cerevisiae/enzimologia , Triticum/química , beta-Frutofuranosidase/metabolismo , Pão/análise , Fermentação , Frutanos/análise , Frutanos/metabolismo , Hidrólise , Síndrome do Intestino Irritável/patologia , Sacarose/metabolismo , Fermento Seco
11.
J Sci Food Agric ; 100(7): 2953-2962, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32031262

RESUMO

BACKGROUND: The composition of drip brew coffee versus brewing time has been chemically characterized in previous studies, and it is known that the total dissolved solids (TDS) systematically decreases with each fraction during the brew. Little information exists regarding the corresponding sensory attributes versus time, however, and it is unclear how TDS correlates with flavor profile. RESULTS: Standard drip brews were fractionated into distinct samples by switching in an empty carafe every 30 s during the brew. Using a trained sensory descriptive panel, we found that most taste and flavor attributes decreased with brew time; for example, the earlier fractions were systematically more bitter and more sour than later fractions. Surprisingly, however, several flavor and taste attributes increased in time; for example, later fractions were systematically sweeter and more floral than earlier fractions. Since later fractions had lower TDS, these results indicate that perceived sweetness in drip brew coffee is negatively correlated with TDS. Mass spectrometry measurements of the monosaccharide content in the brews showed that none of the fractions had perceptible concentrations of any monosaccharide. CONCLUSION: The results of the sensory analysis and the monosaccharide analysis suggest that perceptible sweetness in coffee is a consequence of masking effects and/or the presence of sweet-associated aromas and flavors. The results further suggest that unique flavor profiles could be obtained from the same coffee grounds by judicious combinations of specific fractions. © 2020 Society of Chemical Industry.


Assuntos
Café/química , Monossacarídeos/análise , Odorantes/análise , Paladar , Adulto , Culinária/métodos , Humanos , Fatores de Tempo
12.
J Agric Food Chem ; 68(8): 2588-2596, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32031793

RESUMO

Monosaccharides play important roles in plant growth and development, and their biofunctions are closely related to their endogenous contents. Therefore, the determination of monosaccharides is beneficial for the further study of monosaccharide biofunction. In this work, we developed a liquid chromatography-mass spectrometry analytical method assisted by a post-column derivatization technique (LC-PCD-MS) for the fast and automatic determination of 16 monosaccharides in samples. Post-column chemical derivatization of monosaccharides was performed by a reaction of monosaccharides with 4-benzylaminobenzeneboronic acid (4-PAMBA) through boronate ester formation in a three-way connector. 4-PAMBA worked as a derivatization reagent to improve the selectivity and sensitivity of monosaccharide detection by MS. The developed LC-PCD-MS method integrates LC separation, chemical derivatization, and MS detection in one run, thus greatly reducing the analysis time for each sample. The limits of detection and limits of quantification for 16 monosaccharides were in the range of 0.002-0.1 and 0.007-0.5 ng/mL, respectively. Good linearity was obtained from the linear regression, with a determination coefficient (R2) ranging from 0.9928 to 1.0000. The relative recoveries were in the range of 80.7-117.8%, with the intra- and interday relative standard deviations less than 19.7 and 16.5%, respectively, indicating good accuracy and acceptable reproducibility of the method. Finally, the method was successfully applied to investigate the spatial and temporal distribution of 16 monosaccharides in the developing flower and germinating seed of Arabidopsis thaliana.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Monossacarídeos/análise , Espectrometria de Massas em Tandem/métodos , Arabidopsis/química , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Cromatografia Líquida de Alta Pressão/instrumentação , Flores/química , Flores/crescimento & desenvolvimento , Flores/metabolismo , Limite de Detecção , Monossacarídeos/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Espectrometria de Massas em Tandem/instrumentação
13.
Food Chem ; 315: 126221, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32000077

RESUMO

Xylo- and arabinoxylo-oligosaccharides (XOS and AXOS) are of interest for their prebiotic activity. The production of these oligomers might be accompanied with monosaccharides. The measurement of both oligosaccharides and monosaccharides usually requires two methods. The current work presents an HPAEC-PAD method based on gradient elution of aqueous solvents sodium hydroxide and sodium acetate, in contrast to conventional isocratic elution, for the simultaneous separation of 16 standards of monosaccharides, xylo-oligosaccharides, arabinoxylo-oligosaccharides and uronic acids using CarboPac PA 200 column. The presented method showed a stable baseline and high-resolution separation of the standards. The method showed acceptable accuracy and precision. Limits of Detection and Quantitation (LOD and LOQ) were estimated for all the standards. The method was applied to measure the activity of a commercial endoxylanase on wheat bran; a steady release of xylose monosaccharide was observed. Enzyme action on oligosaccharide standards showed a preference for the larger oligosaccharides.


Assuntos
Monossacarídeos/análise , Oligossacarídeos/análise , Prebióticos/análise , Triticum/química , Arabinose/análise , Arabinose/metabolismo , Cromatografia por Troca Iônica , Fibras na Dieta , Grão Comestível/química , Endo-1,4-beta-Xilanases/metabolismo , Limite de Detecção , Monossacarídeos/metabolismo , Oligossacarídeos/metabolismo , Reprodutibilidade dos Testes , Ácidos Urônicos/química , Xilose/análise , Xilose/metabolismo
14.
Food Chem ; 314: 126219, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31978715

RESUMO

In order to further determine the interaction between polysaccharides and polyphenols, the complex of soluble dietary fiber (SDF) and two phenols were prepared. According to the results, at the conditions of pH = 4, temperature = 60 °C, concentration ratio of polysaccharide and phenol = 4:1, the maximum adsorption of catechin and gallic acid in the SDF complex was 155.74 and 134.05 mg/g, respectively. Due to UV-Vis and FT-IR analysis, it could be speculated that the interaction between SDF and phenols resulted in chemical combination. Furthermore, the monosaccharide composition and molecular weight distribution of SDF were significantly altered after conjugated with phenols. However, it showed no significant difference between two different SDF-phenol complexes, referring to GC and GPC data. The surface of SDF-phenol complex was loose with uniform arrangement, while the physical mixture surface was porous with irregular holes and cracks. Both SDF-CC and SDF-GA complex indicated higher thermal stability than the mixtures by TGA analysis.


Assuntos
Fibras na Dieta/análise , Lotus/química , Raízes de Plantas/química , Polifenóis/análise , Catequina/análise , Carboidratos da Dieta/análise , Ácido Gálico , Monossacarídeos/análise , Fenóis/análise , Polifenóis/química , Polissacarídeos , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Nutrients ; 12(1)2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31947991

RESUMO

Food is often considered to be a precipitating factor of irritable bowel syndrome (IBS) symptoms. In recent years, there has been a growing interest in FODMAPs (Fermentable Oligo-, Di-, Mono-saccharides, And Polyols), which can be found in many common foods. A low FODMAP diet (LFD) is increasingly suggested for IBS treatment. However, long-term, large, randomized controlled studies are still lacking, and certainties and doubts regarding LFDs have grown, often in a disorderly and confused manner. Some potential LFD limitations and concerns have been raised, including nutritional adequacy, cost, and difficulty in teaching the diet and maintaining it. Most of these limitations can be solved with the involvement of a skilled nutritionist, who can clearly explain the different phases of the LFD and ensure nutritional adequacy and compliance. Further studies should focus on new methods of teaching and learning the LFD and on predictors of response. Moreover, particular interest should be focused on the possible use of LFD in gastrointestinal diseases other than functional disorders and, possibly, also in non-gastrointestinal diseases. The aim of the present review was to clarify the effective and appropriate indications and limitations of an LFD and to discuss its possible future uses.


Assuntos
Dieta com Restrição de Carboidratos/métodos , Síndrome do Intestino Irritável/dietoterapia , Dissacarídeos/análise , Fermentação , Análise de Alimentos , Humanos , Monossacarídeos/análise , Oligossacarídeos/análise , Polímeros/análise
16.
Int J Biol Macromol ; 147: 284-294, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31926226

RESUMO

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, has gradually emerged as a public health challenge worldwide. Carrageenan is a popular food additive that has been in use for decades. However, controversy exists regarding to the safety of carrageenan due to its exacerbation of colitis in experimental models. In this study, we studied the effects of vehicle and host intestinal microflora on carrageenan inflammatory properties in C57BL/6 J mice. We found that in high-fat diet model, native carrageenan in drinking water increased the disease activity index (DAI), myeloperoxidase (MPO) activity and the mRNA expression of TLR4 in colon, whereas carrageenan-supplemented diet has no visible effects. However, no signs of colitis were observed under low-fat diet regardless of the mode of vehicle used. Moreover, we discovered that carrageenan-induced colitis in high-fat diet model was robustly correlated with changes in the composition of gut microbiota, specifically Alistipes finegoldii and Bacteroides acidifaciens. Hence, we propose that the inflammatory property of carrageenan is influenced greatly by its intake form via modification of host intestinal microecology.


Assuntos
Colite/induzido quimicamente , Colite/microbiologia , Microbioma Gastrointestinal , Interações Hospedeiro-Patógeno , Intestinos/microbiologia , Animais , Carragenina , Colo/patologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Água Potável/química , Inflamação/patologia , Masculino , Camundongos Endogâmicos C57BL , Peso Molecular , Monossacarídeos/análise , Peroxidase/metabolismo , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
17.
Int J Biol Macromol ; 146: 431-443, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31904462

RESUMO

Pressurized hot water extraction (PHWE), known as a "green" extraction technique, was used to obtain polysaccharide from the pulp of gabiroba (Campomanesia xanthocarpa Berg) fruits. The effects of pressure, temperature, and flow rate on pectin yields were analyzed through a full factorial design experiment 23. The optimal extraction conditions to achieve maximum pectin yield (5.70 wt%) were pressure of 150 bar, temperature of 120 °C, and flow rate of 1.5 mL min-1. The high pressure (100 bar) promoted an increase in galacturonic acid content (36.0%) compared to conventional hot water extraction (CEGP) with 25.7%. Differences in the proportion of homogalacturonan (HG) and rhamnogalacturonan (RG-I) domains ranging from 16.3 to 35.4% and 61.7 to 80.1%, respectively, were observed for each pectin sample according to the extraction conditions. The mono-dimensional (13C-NMR) and bi-dimensional (1H/13C HSQC-NMR) analyses confirmed the presence of HG and RG-I regions and indicated the presence of arabinogalactans type I (AG-I) and arabinogalactans type II (AG-II) in the PHWE pectin samples, which was not found for pectins from gabiroba pulp obtained by CEGP. The results showed that PHWE proved to be a promising method for extracting pectins from gabiroba fruits.


Assuntos
Frutas/química , Temperatura Alta , Myrtaceae/química , Pectinas/química , Pectinas/isolamento & purificação , Pressão , Água/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Monossacarídeos/análise , Espectroscopia de Prótons por Ressonância Magnética , Análise de Regressão
18.
Int J Biol Macromol ; 146: 462-474, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923487

RESUMO

The emphasis of this study lies in that we present a novel fluorescence scanning approach to evaluate the antioxidant capacity of Fritillaria ussuriensis polysaccharide-zinc (FUP-Zn) complex. FUP was extracted successfully, and the corresponding FUP-Zn complexes with different substitution degrees were obtained after modified chemically with ZnCl2. The physiochemical characteristics of the as-prepared samples were determined by ultraviolet-visible spectroscopy, infrared spectroscopy, X-ray powder diffraction, scanning electron microscope, energy dispersive spectrum, thermo gravimetric-differential thermal analyses and etc., and these characterization results confirmed the successful synthesis of FUP-Zn complexes with good stability. The scavenging ability investigation of FUP-Zn complexes towards hydroxyl radicals and superoxide anion radicals carried out by us has revealed that the integration of FUP and Zn greatly enhanced the antioxidant activity due to the synergistic effect and larger pore size of FUP-Zn complexes, and the antioxidant activity of FUP-Zn complex with different substitution degrees is heavily dependent on the amount of Zn. This study indeed provides vital theoretical basis for the promising antioxidant and zinc supplement evaluation from more novel polysaccharide-zinc complexes with suited Zn amount.


Assuntos
Antioxidantes/farmacologia , Fritillaria/química , Polissacarídeos/farmacologia , Zinco/farmacologia , Adsorção , Depuradores de Radicais Livres/farmacologia , Peso Molecular , Monossacarídeos/análise , Nitrogênio/química , Polissacarídeos/ultraestrutura , Solubilidade , Espectrometria de Fluorescência , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxidos/química , Difração de Raios X
19.
Int J Biol Macromol ; 146: 508-517, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923490

RESUMO

Impacts of hot water extraction (HWE), pressurized water extraction (PWE), high-speed shearing homogenization extraction, microwave assisted extraction (MAE), ultrasound assisted extraction (UAE), ultrasound assisted enzymatic extraction, and ultrasound-microwave assisted extraction (UMAE) on physicochemical characteristics and bioactivities of polysaccharides from loquat (Eriobotrya japonica) leaves (LLPs) were investigated. Results showed that the degrees of esterification, contents of phenolics and uronic acids, constituent monosaccharides, apparent viscosities, and molecular weights of LLPs varied by different extraction methods. Bioactivities of LLPs were also significantly affected by different extraction methods. The high molecular weight and high degree of esterification of LLP-W and LLP-P extracted by HWE and PWE, respectively, might contribute to their strong binding capacities. The strong antioxidant activities and inhibitory effects on α-amylase and α-glucosidase were found in LLP-M and LLP-U extracted by MAE and UAE, respectively, which might be attributed to their contents of uronic acids, contents of total phenolics, and molecular weights. The low molecular weights and viscosities of LLP-U and LLP-UM extracted by UMAE might contribute to their strong prebiotic effects. These findings could provide scientific foundations for selecting appropriate extraction methods to obtain LLPs with desired bioactivities for applications in the pharmaceutical and functional food industries.


Assuntos
Fenômenos Químicos , Eriobotrya/química , Folhas de Planta/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Antioxidantes/farmacologia , Benzotiazóis/química , Compostos de Bifenilo/química , Colesterol/metabolismo , Esterificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Peso Molecular , Monossacarídeos/análise , Óxido Nítrico/metabolismo , Picratos/química , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Sulfônicos/química , Viscosidade , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
20.
Int J Biol Macromol ; 147: 350-362, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31923501

RESUMO

Two pectin-polysaccharides, ASP-B2 (Mw, 5.32 kDa) and B3 (Mw, 30.51 kDa), were obtained from Acanthopanax senticosus leaves. An HILIC-UPLC-ESI--HCD-MS/MS technique was introduced for structural elucidations of skeletal structure of pectin-polysaccharides in addition to empolying SEC-MALLS, GC-MS, UPLC-ESI+-MS, methylation analysis, FT-IR and NMR methods. Skeletal structure of ASP-B2 was characterized by combining HG smooth region and RG hairy region with a 2:1 chain length ratio, wheres ASP-B3 had a distinguishing 3:1 chain length ratio (HG:RG). HG were defined as repeated →4GalA1→, and RG were featured by repeated →4GalA1 â†’ 2Rhap1 â†’ with branched points at C-3, C-4 and C-3,4 of rhamnosyl. Side chains mainly consisted of galactans, arabinans and arabinogalactans. Both showed a random coil conformation and no triple-helix conformation. ASP-B2 and B3 possess stronger DPPH and hydroxyl radical scavenging activities, with a relatively low reducing power. Thus, two polysaccharides can be further explored as novel natural antioxidant.


Assuntos
Antioxidantes/farmacologia , Eleutherococcus/química , Folhas de Planta/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Vermelho Congo/química , Metilação , Monossacarídeos/análise , Pectinas/química , Polissacarídeos/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem
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