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1.
Planta ; 257(4): 82, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36917364

RESUMO

MAIN CONCLUSION: Significantly thickened corner middle lamella of the hydroid cell wall in the stipe of dendroid moss Hypnodendron menziesii has a mechanical support function. The hydroid cell walls of the erect stipe of Hypnodendron menziesii were investigated using light microscopy (LM), transmission electron microscopy (TEM), and TEM-immunogold labeling in support of the proposed biomechanical function for the highly thickened cell corner middle lamellae. The statistical analyses of dimensions of hydroid cell and wall parameters revealed a strong positive correlation between the area of hydroid cell and (i) the hydroid cell walls adhering to thick corner middle lamella, (ii) the area of the thick cell wall at hydroid corners, and (iii) the maximum thickness of cell wall at hydroid corners. The total area of the thick cell wall at the hydroid corners concomitantly increased with the area of the hydroid cell wall adhering to the middle lamella, and with the increased number of hydroids surrounding a reference hydroid. The results suggest that markedly thickened middle lamellae of the hydroid cell wall in Hypnodendron likely function by preventing hydroid cells from collapsing under the tensile forces generated from the transpirational pull on the water column. The specific localization of (1→4)- ß-D-galactan and (1,5)-α-L-arabinan in the interface region of the hydroid cell wall and the thick middle lamella is consistent with these cell wall components being involved in the mechanical strengthening of the interface through firm adhesion as well as elasticity, ensuring the structural stability of this cell wall region, which may be prone to delamination/fracturing from the various internal and external pressures imposed. The copious presence of homogalacturonan in the thick middle lamella may further enhance the strength and flexibility of hydroid cell walls.


Assuntos
Bryopsida , Células Germinativas Vegetais , Microscopia , Galactanos/análise , Parede Celular/metabolismo
2.
Int J Biol Macromol ; 209(Pt A): 923-934, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35447261

RESUMO

Determining the structure of REPI, an immunostimulatory polysaccharide fraction from radish leaves, is an important health objective. Herein, we show that REP-I contains nine different monosaccharides, including GalA (22.2%), Gal (32.6%), Ara (27.5%), and Rha (10.2%) as main sugars. REP-I was also reacted with ß-glucosyl Yariv reagent (29.8%), suggesting the presence of the arabino-ß-3,6-galactan. Furthermore, methylated-product analysis revealed that REP-I contains 13 different glycosyl linkages, including 4-linked GalpA (21.0%), 2,4-linked Rhap (7.0%), 4-linked Galp (5.8%), 5-linked Araf (10.1%), and 3,6-linked Galp (7.9%), which are characteristic of RG-I. Microstructural information was obtained by sequential degradation using four linkage-specific glycosylases and ß-elimination, with fragments analyzed on the basis of sugar composition, methylation, and MS/MS spectra. The results show that the immunostimulatory activity of REP-I is possibly due to the structure of RG-I, which is composed of a main chain with repeating [→2)-Rhap-(1 â†’ 4)-GalpA-(1→] linkage units and three side-chains: a branched α(1 â†’ 5)arabinan, a ß(1 â†’ 4)galactan, and arabino-ß-3,6-galactan, which are branched at the C(O)4 position of each Rha residue in the REP-I main chain.


Assuntos
Raphanus , Sequência de Carboidratos , Galactanos/análise , Pectinas/química , Folhas de Planta/química , Polissacarídeos/química , Ramnogalacturonanos , Espectrometria de Massas em Tandem
3.
Planta ; 255(5): 108, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35449484

RESUMO

MAIN CONCLUSION: In cells of growing rye roots, xyloglucans and homogalacturonans demonstrate developmental stage specificity, while different xylans have tissue specificity. Mannans, arabinans and galactans are also detected within the protoplast. Mannans form films on sections of fresh material. The primary cell walls of plants represent supramolecular exocellular structures that are mainly composed of polysaccharides. Cell wall properties and architecture differ between species and across tissues within a species. We revised the distribution of cell wall polysaccharides and their dynamics during elongation growth and histogenesis in rye roots using nonfixed material and the spectrum of antibodies. Rye is a member of the Poaceae family and thus has so-called type II primary cell walls, which are supposed to be low in pectins and xyloglucans and instead have arabinoxylans and mixed-linkage glucans. However, rye cell walls at the earliest stages of cell development were enriched with the epitopes of xyloglucans and homogalacturonans. Mixed-linkage glucan, which is often considered an elongation growth-specific polysaccharide in plants with type II cell walls, did not display such dynamics in rye roots. The cessation of elongation growth and even the emergence of root hairs were not accompanied by the disappearance of mixed-linkage glucans from cell walls. The diversity of xylan motifs recognized by different antibodies was minimal in the meristem zone of rye roots, but this diversity increased and showed tissue specificity during root growth. Antibodies specific for xyloglucans, galactans, arabinans and mannans bound the cell content. When rye root cells were cut, the epitopes of xyloglucans, galactans and arabinans remained within the cell content, while mannans developed net-like or film-like structures on the surface of sections.


Assuntos
Mananas , Secale , Parede Celular/metabolismo , Epitopos/metabolismo , Galactanos/análise , Glucanos/metabolismo , Mananas/metabolismo , Pectinas/metabolismo , Polissacarídeos/metabolismo , Secale/metabolismo , Xilanos/metabolismo
4.
Food Chem ; 359: 129899, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33965763

RESUMO

A low methyl-esterified pectin (33.2% methyl-esterification degree) was isolated from the tuber of Dioscorea opposita Thunb., which was an edible and medicinal material in China. This pectin (Mw of 1.3 × 104 g/mol) contained the ~59.1% homogalacturonan (HG) and ~38.1% highly branched rhamnogalacturonan I (RG-I) region with possible side chains embracing arabinogalactan II, arabinan or arabinogalactan I. The fragments including HG backbone consisting of â†’ 4)-α-GalpA-(1 â†’ and â†’ 4)-α-GalpA-6-O-methyl-(1 â†’ with molar ratio of ~2:1, and repeating unit of arabinogalactan II side chain composed of α-Araf-(1 â†’ and â†’ 3,6)-ß-Galp-(1→, were speculated through methylation analysis and NMR spectra. However, the linkage pattern for RG-I backbone and side chains were indiscernible due to limited resolution of NMR spectra. Besides, the pectin adopted a flexible chain conformation in 0.1 M NaNO3 solution. These results provided a structural basis for study on polysaccharide from D. opposite, which was benefit for development of functional food of yam.


Assuntos
Dioscorea/química , Pectinas/isolamento & purificação , Configuração de Carboidratos , China , Galactanos/análise , Galactanos/química , Galactanos/isolamento & purificação , Pectinas/análise , Pectinas/química , Plantas Medicinais/química , Polissacarídeos/análise , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
5.
Int J Biol Macromol ; 167: 1059-1065, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33188809

RESUMO

It is generally recognized that banana has diverse health benefits. However, most of the molecules responsible for the health benefits remain unknown. In this work, an important polysaccharide was extracted from banana and purified. The molecular weight was determined to be 526.2 kDa. It was identified by chemical and spectroscopic methods as arabinogalactan with ß-D-(1→6)-galactan as backbone. This arabinogalactan was comprised of three monosaccharides, including Ara, Gal and GlcA with a relatively molar ratio of 5.8: 5.9: 1.0. The side chains were identified to be α-L-Araf-(1→, ß-D-GlcpA-(1→, α-L-Araf-(1→5)-α-L-Araf-(1→ and α-D-Galp-(1→3)-α-L-Araf-(1→. They were linked to ß-D-(1→6)-galactan at O-3, respectively. The putative structure was drawn as below. This arabinogalactan could induce NO production. It could also inhibit ROS production with a dose-dependent behaviour.


Assuntos
Galactanos/química , Galactanos/farmacologia , Musa/química , Animais , Fenômenos Químicos , Análise de Alimentos , Galactanos/análise , Glicosídeos , Imunomodulação , Espectroscopia de Ressonância Magnética , Camundongos , Peso Molecular , Monossacarídeos/química , Células RAW 264.7 , Relação Estrutura-Atividade
6.
Planta ; 251(5): 100, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32328732

RESUMO

MAIN CONCLUSION: ß-(1,4)-galactan determines the interactions between different matrix polysaccharides and cellulose during the cessation of cell elongation. Despite recent advances regarding the role of pectic ß-(1,4)-galactan neutral side chains in primary cell wall remodelling during growth and cell elongation, little is known about the specific function of this polymer in other developmental processes. We have used transgenic Arabidopsis plants overproducing chickpea ßI-Gal ß-galactosidase under the 35S CaMV promoter (35S::ßI-Gal) with reduced galactan levels in the basal non-elongating floral stem internodes to gain insight into the role of ß-(1,4)-galactan in cell wall architecture during the cessation of elongation and the beginning of secondary growth. The loss of galactan mediated by ßI-Gal in 35S::ßI-Gal plants is accompanied by a reduction in the levels of KOH-extracted xyloglucan and an increase in the levels of xyloglucan released by a cellulose-specific endoglucanase. These variations in cellulose-xyloglucan interactions cause an altered xylan and mannan deposition in the cell wall that in turn results in a deficient lignin deposition. Considering these results, we can state that ß-(1,4)-galactan plays a key structural role in the correct organization of the different domains of the cell wall during the cessation of growth and the early events of secondary cell wall development. These findings reinforce the notion that there is a mutual dependence between the different polysaccharides and lignin polymers to form an organized and functional cell wall.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Parede Celular/química , Cicer/enzimologia , Galactanos/análise , Pectinas/química , beta-Galactosidase/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Parede Celular/metabolismo , Celulose/análise , Cicer/genética , Galactanos/metabolismo , Lignina/análise , Pectinas/metabolismo , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Xilanos/análise , beta-Galactosidase/genética
7.
Food Chem ; 316: 126338, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32036182

RESUMO

Dietary fibre (DF) profiles of natural hazelnut, roasted hazelnut and hazelnut skin were analyzed. Insoluble (IDF) and soluble (SDF) DFs were examined for monosaccharide and glycosyl-linkage compositions using gas chromatography-mass spectrometry (GC-MS). Total DF contents of natural hazelnut, roasted hazelnut, and hazelnut skin were 17.8, 15.4, and 69.8%, respectively; majority of which (>96%) were water-insoluble. IDFs of natural and roasted hazelnuts were composed of cellulose (~49%), pectic polysaccharides (~30%), and xyloglucans (~15%), whereas that of hazelnut skin made up lignin (~55%) and fibre polysaccharides (cellulose, pectic polysaccharides, and xyloglucans, ~45%). Unlike the ones from other sources, pectic polysaccharides in IDFs had lower proportion of smooth region and higher proportion of hairy region that is heavily branched with arabinan and galactan side chains. Xyloglucans were also densely branched with monomeric and/or dimeric side chains. SDFs of the samples were composed of heavily branched heteromannans (~60%), slightly branched pectic polysaccharides (~25%), and xyloglucans possessing monomeric side chains (~5%). These results suggest that hazelnut is rich in DFs that have potential to improve large bowel function and hazelnut skin, a byproduct of hazelnut roasting process, could be utilized for the production of functional carbohydrates having prebiotic capacities.


Assuntos
Corylus/química , Fibras na Dieta/análise , Galactanos/análise , Cromatografia Gasosa-Espectrometria de Massas , Glucanos/análise , Pectinas/análise , Polissacarídeos/análise , Turquia , Xilanos/análise
8.
Food Chem ; 298: 124745, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260966

RESUMO

The chemical and sensory profiles of wines prepared from Cabernet Sauvignon grapes at different ripening stages vary greatly. Here, the soluble cell wall carbohydrate (SCWC) and phenolic profiles of wines were analyzed in parallel with the sensory evaluation of their mouthfeel and taste characteristics. Both SCWCs and phenolic compounds correlated with wine mouthfeel. When analyses were extended to specific classes of cell wall carbohydrates, it was shown that rhamnogalacturonan I/II, arabinan, arabinogalactan types I and II and xyloglucan from grapes were the key determinants of overall mouthfeel descriptors, particularly viscosity, astringency and roughness, whereas heteromannan from grapes was associated with mouth coating and chalkiness. A perceived sour taste was notably associated with higher homogalacturonan contents. This finding provides insights into the contributions of non-phenolic compounds to wine mouthfeel. The data provide opportunities for the development of simple monosaccharide marker assays to monitor major mouthfeel characteristics in red wines.


Assuntos
Carboidratos/análise , Parede Celular/química , Paladar , Vitis/química , Vinho/análise , Adstringentes/análise , Galactanos/análise , Humanos , Peso Molecular , Boca , Pectinas/análise , Fenóis/análise
9.
Food Chem ; 295: 548-555, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174794

RESUMO

The retrogradation behaviors and molecular structures of lotus seed starch (LS) combined with different hydrocolloids, chitosan (CS), guar gum (GG) and xanthan (XN), were investigated. Following an autoclave treatment, the storage modulus (G') value of LS-CS increased more rapidly than LS alone, indicating an increase in starch retrogradation. This might result from intermolecular interactions, increased ordered structure, decreased weight-average molecular weight (Mw) and greater leached amylose content in LS-CS system. The LS-GG and particularly LS-XN blends showed the opposite trend. The much greater Mw of LS-XN was mainly attributed to the lower retrogradation rate. The enwrapping effect of GG or XN on LS, as observed by confocal laser scanning microscopy, might retard their retrogradation by limiting the granules' swelling and the amylose leaching. Overall, the changes in the interaction force, ordered structure, Mw, leached amylose and microstructure were related to retrogradation behaviors of LS-hydrocolloid blends following an autoclave treatment.


Assuntos
Coloides/química , Lotus/metabolismo , Amido/química , Amilose/química , Quitosana/análise , Galactanos/análise , Temperatura Alta , Mananas/análise , Microscopia de Força Atômica , Peso Molecular , Gomas Vegetais/análise , Polissacarídeos Bacterianos/análise , Reologia , Sementes/metabolismo
10.
Food Res Int ; 120: 188-195, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31000229

RESUMO

By virtue of exclusive nutrient composition and nutritional properties, seed germ flours from both European carob (Ceratonia siliqua L.) and South American algarrobo (Prosopis alba and Prosopis nigra) or vinal (Prosopis ruscifolia) have potential as a high nutritional value and health-promoting ingredient for food formulations. In order to define their compositional and functional properties, we investigated the germ protein content of carob compared to the P. alba, P. nigra and P. ruscifolia counterparts, applying proteomics and complementary methods. The mono- and two-dimensional electrophoretic profiles of Prosopis spp. were very similar among one another, while C. siliqua exhibited significant differences. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy highlighted a dominant ß-sheet structural conformation for C. siliqua, suggesting that carob germ flour might more suited than Prosopis germ flour for baking and food technological applications. In contrast, Prosopis spp. contained a more adequate nutritional value than C. siliqua, in terms of essential amino acid complement. Both carob and algarrobo germ flour samples were highly digestible, as demonstrated by in vitro simulated gastrointestinal digestion, releasing high amounts of free amino acids and only minor proportions of low molecular weight peptides.


Assuntos
Fabaceae/química , Farinha/análise , Prosopis/química , Proteínas/análise , Sementes/química , Aminoácidos , Aminoácidos Essenciais/análise , Antioxidantes/análise , Eletroforese em Gel de Poliacrilamida , Galactanos/análise , Mananas/análise , Valor Nutritivo , Gomas Vegetais/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem
11.
Food Chem ; 286: 179-184, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827593

RESUMO

Two polysaccharide fractions sequentially extracted with water 1W and alkali 1A, were isolated from the hazelnut skins. The monosaccharide composition together with the FTIR and NMR analyses, indicated that both fractions are formed from a mixture of polysaccharides. The fraction 1W consists of methyl-esterified pectic polysaccharide with rhamnogalacturonan I blocks, branching with arabinose side chains, and with 1,5-, 1,3,5-arabinan and galactan polysaccharides. The fraction 1A is a mixture of deesterified rhamnogalacturonan I and 1,5-, 1,3,5-arabinan and 4-O-Me-glucuronoxylan polysaccharides. The presence of unsaturated galacturonic acid and the heterogeneity of the molecular weights, which Mw ranged between 3.6 and 39 kg mol-1, indicated the pectin degradation during roasting.


Assuntos
Corylus/química , Tecnologia de Alimentos/métodos , Polissacarídeos/química , Galactanos/análise , Ácidos Hexurônicos/análise , Espectroscopia de Ressonância Magnética , Peso Molecular , Monossacarídeos/análise , Pectinas/análise , Polissacarídeos/análise , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Artigo em Inglês | MEDLINE | ID: mdl-30475683

RESUMO

This study aims to investigate the effects of microwave, combined microwave/hot air treatment and hot air-only roasting on the formation of heat-induced contaminants of carob powders. Moisture content, water activity and pH values of the product decreased with the increasing roasting time and microwave power, while browning index (BI) and ultraviolet absorbance (UV-A) values were increased. While L and b values of carob powders decreased with increasing the roasting time and microwave power, a and ΔE values were increased. Varying roasting conditions also significantly affected the content of Maillard reaction products (MRPs): 5-hydroxymethylfurfural (HMF) (0.69-28.32 mg/kg dry matter), furfural (

Assuntos
Ar , Contaminação de Alimentos/análise , Galactanos/análise , Temperatura Alta , Mananas/análise , Micro-Ondas , Gomas Vegetais/análise , Pós/química
13.
Food Chem ; 267: 319-328, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29934174

RESUMO

Yellow lupin polysaccharides (YLP-1, YLP-2 and YLP-3) were isolated from the whole seeds of Lupinus luteus L. Their antioxidant activities were evaluated by ABTS+ and hydroxyl radical scavenging, and Fe2+ chelating assays. Immunostimulatory activities were measured by their ability to activate macrophages to produce TNF-α and NO. Four strains of probiotic bacteria were used to measure their prebiotic activities. YLP-2 with largest galactose content displayed the best activity amongst the three isolated polysaccharides. NMR and FT-IR spectroscopic methods have revealed that YLPs contain galactans and galactomannans which are linked with ß-(1,4) glycosidic bond in the main chain. The side chain Galp unit of galactomannan is connected to the main chain Manp by α-(1,6) linkage. The results presented in this paper strongly suggest that YLPs display significant antioxidant, immunostimulatory and prebiotic activities and hence hold great potential as nutraceutical and functional agents.


Assuntos
Antioxidantes/farmacologia , Fatores Imunológicos/farmacologia , Lupinus/química , Polissacarídeos/farmacologia , Prebióticos , Animais , Antioxidantes/química , Bifidobacterium/fisiologia , Configuração de Carboidratos , Citocinas/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Galactanos/análise , Galactose/análogos & derivados , Fatores Imunológicos/química , Lactobacillus/fisiologia , Espectroscopia de Ressonância Magnética , Mananas/análise , Camundongos , Polissacarídeos/química , Células RAW 264.7 , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Nutrition ; 49: 51-56, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29495000

RESUMO

OBJECTIVES: This study aimed to provide an overview of the characteristics of thickened formulas to aid health care providers manage infants with regurgitations. METHODS: The indications, properties, and efficacy of different thickening agents and thickened formulas on regurgitation and gastroesophageal reflux in infants were reviewed. PubMed and the Cochrane database were searched up to December 2016. RESULTS: Based on the literature review, thickened formulas reduce regurgitation, may improve reflux-associated symptoms, and increase weight gain. However, clinical efficacy is related to the characteristics of the formula and of the infant. Commercial thickened formulas are preferred over the supplementation of standard formulas with thickener because of the better viscosity, digestibility, and nutritional balance. Rice and corn starch, carob bean gum, and soy bean polysaccharides are available as thickening agents. Hydrolyzed formulas have recently shown promising additional benefit. CONCLUSIONS: Thickened formulas reduce the frequency and severity of regurgitation and are indicated in formula-fed infants with persisting symptoms despite reassurance and appropriate feeding volume intake.


Assuntos
Refluxo Gastroesofágico/prevenção & controle , Fórmulas Infantis/química , Digestão , Galactanos/análise , Esvaziamento Gástrico/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Mananas/análise , Oryza/química , Gomas Vegetais/análise , Polissacarídeos/análise , Glycine max/química , Amido/análise , Viscosidade , Aumento de Peso , Zea mays/química
15.
Appl Environ Microbiol ; 84(8)2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29453259

RESUMO

The development of unconventional oil and gas (UOG) resources results in the production of large volumes of wastewater containing a complex mixture of hydraulic fracturing chemical additives and components from the formation. The release of these wastewaters into the environment poses potential risks that are poorly understood. Microbial communities in stream sediments form the base of the food chain and may serve as sentinels for changes in stream health. Iron-reducing organisms have been shown to play a role in the biodegradation of a wide range of organic compounds, and so to evaluate their response to UOG wastewater, we enriched anaerobic microbial communities from sediments collected upstream (background) and downstream (impacted) of an UOG wastewater injection disposal facility in the presence of hydraulic fracturing fluid (HFF) additives: guar gum, ethylene glycol, and two biocides, 2,2-dibromo-3-nitrilopropionamide (DBNPA) and bronopol (C3H6BrNO4). Iron reduction was significantly inhibited early in the incubations with the addition of biocides, whereas amendment with guar gum and ethylene glycol stimulated iron reduction relative to levels in the unamended controls. Changes in the microbial community structure were observed across all treatments, indicating the potential for even small amounts of UOG wastewater components to influence natural microbial processes. The microbial community structure differed between enrichments with background and impacted sediments, suggesting that impacted sediments may have been preconditioned by exposure to wastewater. These experiments demonstrated the potential for biocides to significantly decrease iron reduction rates immediately following a spill and demonstrated how microbial communities previously exposed to UOG wastewater may be more resilient to additional spills.IMPORTANCE Organic components of UOG wastewater can alter microbial communities and biogeochemical processes, which could alter the rates of essential natural attenuation processes. These findings provide new insights into microbial responses following a release of UOG wastewaters and are critical for identifying strategies for the remediation and natural attenuation of impacted environments.


Assuntos
Desinfetantes/análise , Etilenoglicol/análise , Galactanos/análise , Fraturamento Hidráulico , Mananas/análise , Microbiota/efeitos dos fármacos , Gomas Vegetais/análise , Águas Residuárias/análise , Anaerobiose , Biodegradação Ambiental , Sedimentos Geológicos/microbiologia
16.
Rev. Inst. Adolfo Lutz ; 77: e1749, 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1489579

RESUMO

As doenças fúngicas invasivas têm sido um problema crescente em ambientes hospitalares, sobretudo nas últimas duas décadas. A aspergilose invasiva (AI), ocasionada pelo gênero Aspergillus, está entre as principais causas de morte em pacientes gravemente imunocomprometidos, com mortalidade que varia de 70 a 90%. O padrão de referência para o diagnóstico de AI é o cultivo do micro-organismo e a análise histopatológica dos órgãos afetados. Estes procedimentos são dificilmente realizados na maioria dos casos, e apresentam baixa sensibilidade (<50%), além de as amostras serem habitualmente obtidas em estados avançados da infecção. O teste de detecção de galactomanana tem sido objeto de estudo para o diagnóstico de AI, por representar uma promissora ferramenta e por ser uma técnica sorológica rápida e não invasiva. A presente revisão tem por objetivo fazer levantamento de estudos que utilizaram o teste de galactomanana em amostras de pacientes com quadros clínicos distintos, porém com suspeita e/ou com comprovada AI, bem como as atuais tendências de conhecimento, aplicação e utilidade do ensaio laboratorial.


Invasive fungal diseases represent an increasing problem in the hospital environments, predominantly in the last two decades. The invasive aspergillosis (IA), induced by Aspergillus species, has been the main cause of death in severely immunocompromised patients, with mortality varying from 70 to 90%. Difficulties are found for diagnosing the IA. In vitro culture of biological material shows low sensitivity (<50%), besides the positivity usually occurs at the advanced stages of the infection. The test for detecting galactomannan has been the object of the present study, seeing that it represents a promising diagnostic tool, as a fast and non-invasive serological procedure. The objective of the present review is to survey the studies which have been performed by using methods for detecting galactomannan in samples from patients with distinct clinical pictures. Patients presenting suspicion and/or confirmed IA were also included, as well as the up-to-date trends in knowledge, application and utility of the test.


Assuntos
Aspergilose Pulmonar Invasiva/diagnóstico , Galactanos/análise , Mananas/análise , Técnicas e Procedimentos Diagnósticos
17.
J Food Sci ; 82(8): 1851-1860, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28631811

RESUMO

The purpose of this work was to investigate iciness perception and other sensory textural attributes of ice cream due to ice and fat structures and mix viscosity. Two studies were carried out varying processing conditions and mix formulation. In the 1st study, ice creams were collected at -3, -5, and -7.5 °C draw temperatures. These ice creams contained 0%, 0.1%, or 0.2% emulsifier, an 80:20 blend of mono- and diglycerides: polysorbate 80. In the 2nd study, ice creams were collected at -3 °C draw temperature and contained 0%, 0.2%, or 0.4% stabilizer, a blend of guar gum, locust bean gum, and carrageenan. Multiple linear regressions were used to determine relationships between ice crystal size, destabilized fat, and sensory iciness. In the ice and fat structure study, an inverse correlation was found between fat destabilization and sensory iciness. Ice creams with no difference in ice crystal size were perceived to be less icy with increasing amounts of destabilized fat. Destabilized fat correlated inversely with drip-through rate and sensory greasiness. In the ice cream mix viscosity study, an inverse correlation was found between mix viscosity and sensory iciness. Ice creams with no difference in ice crystal size were perceived to be less icy when formulated with higher mix viscosity. A positive correlation was found between mix viscosity and sensory greasiness. These results indicate that fat structures and mix viscosity have significant effects on ice cream microstructure and sensory texture including the reduction of iciness perception.


Assuntos
Gorduras/química , Sorvetes/análise , Emulsificantes/química , Aditivos Alimentares/análise , Galactanos/análise , Humanos , Mananas/análise , Gomas Vegetais/análise , Paladar , Temperatura , Viscosidade
18.
J Texture Stud ; 48(3): 221-230, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28573729

RESUMO

The study was aimed to develop protein, dietary fiber, and micronutrient enriched corn snacks through extrusion processing. Corn snacks supplemented with chickpea, defatted soy flour (20-40/100 g) and guar gum (7/100 g) were prepared through extrusion processing. Micronutrients (iron, zinc, iodine, and vitamins A, C, and folic acid) at recommended daily values were added in all formulations. Extruded corn snacks were analyzed for physical, textural, and sensory attributes. Results showed that piece density (0.34-0.44 g/cm3 ), moisture (3.40-5.25%), water activity (0.203-0.361), hardness (64.4-133.2 N), and cohesiveness (0.25-0.44) was increased Whereas, expansion ratio (3.72-2.64), springiness (0.82-0.69), chewiness (1.63-0.42), and resilience (1.37-0.14) was decreased as supplementation with soy and chickpea flour increased from 20 to 40/100 g. Overall corn snack supplemented with 15/100 g of soy and 15/100 g of chickpea flour got the highest acceptance from the sensory panelists. PRACTICAL APPLICATIONS: The article focuses on physical, textural, and sensory attributes of extruded corn snacks enriched with protein, dietary fiber, and micronutrients Awareness about the importance of healthy snacks has grown among the consumers during the last decade. Extruded snacks developed using nutrient rich ingredients with good textural and sensory properties has always remained a challenge for the snack industry. Texture of the extruded snacks varies a lot with high levels of protein and dietary fiber. This study is helpful for the development of healthy snacks especially in developing countries lacking storage infrastructure or tropical environment. Nutrient rich extruded snacks can also be used to alleviate malnutrition by incorporating in school lunch programs.


Assuntos
Fibras na Dieta/análise , Manipulação de Alimentos/métodos , Alimentos Formulados/análise , Micronutrientes/análise , Proteínas de Vegetais Comestíveis/análise , Lanches , Zea mays/química , Adulto , Cicer/química , Cor , Feminino , Galactanos/análise , Humanos , Julgamento , Masculino , Mananas/análise , Valor Nutritivo , Percepção , Gomas Vegetais/análise , Sensação , Alimentos de Soja/análise , Adulto Jovem
19.
J Texture Stud ; 48(3): 198-204, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28573730

RESUMO

Some patients with dysphagia are prone to aspiration of low-viscosity liquids. Thickened liquids are often used in attempts to prevent aspiration. The patients should be given thickened liquids with suitable thickness, and the thickness should be constant at all time. While rotational and cone-and-plate viscometers are used for the evaluation of thickened liquids, they are high-precision and expensive equipment. To control the thickness of liquids, a simple and objective evaluation method is thus necessary. We developed a method to evaluate thickened liquids using funnels, and verified the appropriateness of this method. We measured the outflow times of five thickened liquids through funnels. One of the thickened liquids was a commercially available nutritional supplement, another was made with a thickening agent that contained guar gum, and all others were made with a thickening agent that contained xanthan gum. Four funnels with different stem sizes were tested. We found that the outflow time of thickened liquids through a funnel depended on their viscosities at a shear rate between 10 and 50 s-1 , when the average inner diameter of the stem was in the range of 5.3-9.0 mm, and the volume of the liquid poured into the funnel was 30 mL. The correlation coefficient between the value of the sensory evaluation and the outflow time of the funnel with an average stem ID of 5.3 mm was 0.946. Therefore, this method may be useful in hospital and nursing home kitchens for evaluating thickened liquids. PRACTICAL APPLICATIONS: The findings of this study will help develop a new method for the evaluation of thickened liquids. Funnels made from polypropylene, which are inexpensive and light, were used in this method. The process for measuring the outflow time of thickened liquids through a funnel is simple, and we can obtain quantitative data that are objective. Even though line spread test (LST) is well known as a simple measurement method, nutritional supplements and liquids thickened using a thickening agent containing guar gum have not been evaluated accurately. The funnel method was found to have a stronger correlation with sensory evaluation compared to LST. This method is useful in hospital and nursing home kitchens for evaluating thickened liquids.


Assuntos
Deglutição , Alimentos Formulados/análise , Galactanos/análise , Mananas/análise , Gomas Vegetais/análise , Polissacarídeos Bacterianos/análise , Reologia/instrumentação , Adolescente , Adulto , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/fisiopatologia , Transtornos de Deglutição/terapia , Nutrição Enteral/métodos , Desenho de Equipamento , Feminino , Alimentos Formulados/normas , Galactanos/normas , Humanos , Julgamento , Mananas/normas , Modelos Teóricos , Variações Dependentes do Observador , Gomas Vegetais/normas , Polissacarídeos Bacterianos/normas , Limiar Sensorial , Soluções , Fatores de Tempo , Viscosidade , Adulto Jovem
20.
Exp Parasitol ; 179: 28-35, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28655584

RESUMO

This study investigated the possible biological, biochemical and histological changes in Bradybaena similaris(Gastropoda: Pulmonata) infected by Heterorhabditis indica (Rhabditida: Heterorhabditidae), strain LPP1. Two groups of 16 snails were formed: the control group (unexposed) and the treated group, which was exposed for three weeks to infective juveniles (J3) of H. indica LPP1. The experiment was conducted in duplicate, using a total of 64 snails. After the exposure period, the snails were dissected to collect the hemolymph and tissues, for evaluation of the physiological changes caused by the infection. The number of eggs laid/snail and the viability of these eggs were also assessed as indicators of the reproductive activity of B. similaris. Intense glycogenolysis was accompanied by a significant reduction (p < 0.05) in the glucose content of the hemolymph of the exposed snails, indicating that infection by H. indica induces breakdown of the host's glycemic homeostasis. Significant variations (p < 0.05) in the lactate dehydrogenase activity occurred together with changes in the concentration of pyruvic and lactic acid in the hemolymph of the infected B. similaris snails, corroborating the transition from aerobic to anaerobic metabolism in the hosts. These metabolic alterations reflect the parasitic castration process in this interface. The results suggest that the use of H. indica LPP1 is a potential alternative for biological control of B. similaris.


Assuntos
Gastrópodes/parasitologia , Rhabditoidea/fisiologia , Animais , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Galactanos/análise , Gastrópodes/anatomia & histologia , Gastrópodes/metabolismo , Glucose/metabolismo , Glicogênio/metabolismo , Hemolinfa/química , Hemolinfa/enzimologia , Hemolinfa/metabolismo , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/análise , Mariposas/parasitologia , Ácido Pirúvico/análise
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