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1.
Appl Spectrosc ; 78(4): 355-364, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38378014

RESUMO

The cell wall integrity (CWI) signaling pathway regulates yeast cell wall biosynthesis, cell division, and responses to external stress. The cell wall, comprised of a dense network of chitin, ß-1,3- and ß-1,6- glucans, and mannoproteins, is very thin, <100 nm. Alterations in cell wall composition may activate the CWI pathway. Saccharomyces cerevisiae, a model yeast, was used to study the role of individual wall components in altering the structure and biophysical properties of the yeast cell wall. Near-field Fourier transform infrared spectroscopy (nano-FT-IR) was used for the first direct, spectrochemical identification of cell wall composition in a background (wild-type) strain and two deletion mutants from the yeast knock-out collection: kre6Δ and knr4Δ. Killer toxin resistant 6 (Kre6) is an integral membrane protein required for biosynthesis of ß-1,6-glucan, while Knr4 is a cell signaling protein involved in the control of cell wall biosynthesis, in particular, biosynthesis and deposition of chitin. Complementary spectral data were obtained with far-field (FF)-FT-IR, in transmission, and with attenuated total reflectance (ATR) spectromicroscopy with 3-10 µm wavelength-dependent spatial resolution. The FF-FT-IR spectra of cells and spectra of isolated cell wall components showed that components of the cell body dominated transmission spectra and were still evident in ATR spectra. In contrast, the nano-FT-IR at ∼25 nm spatial resolution could be used to characterize the yeast wall chemical structure. Our results show that the ß-1,6-glucan content is decreased in kre6Δ, while all glucan content is decreased in the knr4Δ cell wall. The latter may be thinner than in wild type, since not only are mannan and chitin detectable by nano-FT-IR, but also lipid membranes and protein, indicative of cell interior.


Assuntos
Proteínas de Saccharomyces cerevisiae , beta-Glucanas , beta-Glucanas/análise , Parede Celular/química , Quitina/análise , Quitina/metabolismo , Glucanos/análise , Glucanos/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Carbohydr Polym ; 331: 121861, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38388057

RESUMO

Endo-xylanase and endo-glucanase are supplemented to poultry diets in order to improve nutrient digestion and non-starch polysaccharide (NSP) fermentation. Here, the action of these enzymes on alcohol insoluble solids (AIS) from wheat and maize grains as well as its implications for starch digestion in milled grains were evaluated in vitro, under conditions mimicking the poultry digestive tract. For wheat AIS, GH11 endo-xylanase depolymerized soluble arabinoxylan (AX) during the gizzard phase, and proceeded to release insoluble AX under small intestine conditions. At the end of the in vitro digestion (480 min), the endo-xylanase, combined with a GH7 endo-ß-1,4-glucanase, released 30.5 % of total AX and 18.1 % of total glucan in the form of arabinoxylo- and gluco-oligosaccharides, as detected by HPAEC-PAD and MALDI-TOF-MS. For maize AIS, the combined enzyme action released 2.2 % and 7.0 % of total AX and glucan, respectively. Analogous in vitro digestion experiments of whole grains demonstrated that the enzymatic release of oligomers coincided with altered grain microstructure, as examined by SEM. In the present study, cell wall hydrolysis did not affect in vitro starch digestion kinetics for cereal grains. This study contributes to understanding the action of feed enzymes on cereal NSP under conditions mimicking the poultry digestive tract.


Assuntos
Grão Comestível , Amido , Animais , Amido/análise , Grão Comestível/química , Aves Domésticas , Polissacarídeos/análise , Dieta , Glucanos/análise , Digestão , Parede Celular , Ração Animal/análise , Endo-1,4-beta-Xilanases
3.
Ann Agric Environ Med ; 30(4): 623-633, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38153064

RESUMO

INTRODUCTION AND OBJECTIVE: Poultry house employees spend a significant part of their work shift being exposed to airborne particulate pollutants. The aim of this study was to assess their exposure at different stages of chicken production cycle, based on quantification of pro-inflammatory mediators (IL-1ß, IL-6, IL-8, and TNFα) in nasal lavage (NAL) samples. MATERIAL AND METHODS: The concentrations of airborne dust at 3 different stages of the production cycle (i.e. empty poultry house, with 7- and 42-day-old chickens) were stationary measured using Grimm spectrometer, as well as CIS and Button samplers. The dust collected by the latter 2 samplers was analyzed for endotoxin and (1→3)-ß-D-glucan content. NAL samples were collected from employees after their work shift to determine the pro-inflammatory mediator levels. RESULTS: The maximum particulate aerosol, endotoxin, and (1→3)-ß-D-glucan concentrations at workplaces reached the levels of 4.12 mg/m3, 45.21 ng/m3, and 56.54 ng/m3, respectively. The IL-1ß, IL-6, and IL-8 concentrations in NAL samples ranged between 0.62-18.12 pg/mL, <0.70-25.37 pg/mL, and <3.50-259.5 pg/mL, respectively. All TNFα levels were below 4 pg/mL. There were no significant differences between these cytokine concentrations in NAL samples collected at different stages of chicken breeding in either 'winter' or 'summer' seasons. CONCLUSIONS: Inhalation stimulation with poultry dust containing endotoxins and (1→3)-ß-D-glucans resulted in the production of pro-inflammatory mediators, which proves the course of immunological processes in the exposed employees that may lead to adverse effects. The use of nasal lavage fluid in the control of such exposure confirms that NAL analysis is a reliable laboratory tool for assessing the impact of poultry dust on exposed farm workers.


Assuntos
Poluentes Ocupacionais do Ar , Exposição Ocupacional , Humanos , Animais , Poeira/análise , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Poluentes Ocupacionais do Ar/análise , Interleucina-8 , Aves Domésticas , Fator de Necrose Tumoral alfa , Interleucina-6 , Mediadores da Inflamação/análise , Galinhas , Endotoxinas/análise , Glucanos/análise , Exposição por Inalação/análise
4.
Molecules ; 28(19)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37836774

RESUMO

It has long been known that containers for sample analysis or storage can play a role in endotoxin recovery and have to be taken into account when determining endotoxin concentrations. However, there is little data on the effects of containers regarding (1→3)-ß-D-glucan, which plays a role as a contaminant in endotoxin measurements. To determine the effect of the container on (1→3)-ß-D-glucan measurements, four different types of containers were investigated at different temperatures and stored for up to 28 days. For short-term storage for 3 h at room temperature, no effect of the container on the (1→3)-ß-D-glucan recovery could be observed, but for storage at -20 °C, the results indicate that the storage time and temperature influences (1→3)-ß-D-glucan detection. All containers showed a trend of lower recoveries over time, but the polyethylene container showed a significantly lower recovery compared to the other containers. We also showed that freeze/thaw cycles had a strong influence on the recovery of (1→3)-ß-D-glucan in polyethylene containers. Our study showed that the container can affect not only the detection of endotoxins but also the detection of (1→3)-ß-D-glucans.


Assuntos
Glucanos , beta-Glucanas , Glucanos/análise , beta-Glucanas/análise , Endotoxinas , Temperatura , Polietilenos
5.
Chem Biodivers ; 20(8): e202300161, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37337851

RESUMO

Aconitum septentrionale is known to contain toxic diterpene alkaloids, while other bioactive compounds in the plant remain unclear. The aim of this study was to explore the phenolic compounds and polysaccharides from the water extract of A. septentrionale roots. Fifteen phenolic compounds were isolated and identified by NMR and MS, including fourteen known and one new dianthramide glucoside (2-[[2-(ß-D-glucopyranosyloxy)-5-hydroxybenzoyl]amino]-4,5-dihydroxybenzoic acid methyl ester, 14). One neutral (complex of glucans with minor amounts of mannans) and two acidic polysaccharide fractions (complexes of pectic polysaccharides and glucans) were also obtained. Hydroxytyrosol (1), hydroxytyrosol-1-O-ß-glucoside (2) and bracteanolide A (7) inhibited the release of nitric oxide by dendritic cells. Magnoflorine (8) and 2-[[2-(ß-D-glucopyranosyloxy)-5-hydroxybenzoyl]amino]-5-hydroxybenzoic acid methyl ester (12) inhibited 15-lipoxygenase, and bracteanolide A (7) was a moderate inhibitor of xanthine oxidase. This study is the first to describe the diversity of phenolics and polysaccharides from A. septentrionale and their anti-inflammatory and anti-oxidant activities.


Assuntos
Aconitum , Aconitum/química , Glucanos/análise , Glucosídeos/química , Fenóis/farmacologia , Fenóis/análise , Raízes de Plantas/química , Polissacarídeos/farmacologia , Polissacarídeos/química
6.
Carbohydr Polym ; 305: 120447, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36737220

RESUMO

A novel reuteran-like glucan with low digestibility was fabricated using microbial glucanotransferase (GTase) treated maltodextrin. For GTase treated maltodextrin with DE 6, the molecular weight of reuteran-like glucan increased from 8.35 × 104 to 5.14 × 106 g/mol in the initial 6 h, increasing to 1.47 × 107 g/mol at 72 h. The short chain fraction (DP 3-12) of reuteran-like glucan increased from 45.2 % to 100.0 %, accompanied by an increase in α-1,6 glycosidic linkage percentage from 3.9 % to 33.3 %. This reaction promoted rearrangements in glycosidic chains, leading to a substantial increase in resistant starch content (13.4 % to 37.4 %) in the reuteran-like glucan. During in vitro fecal fermentation for 48 h, the reuteran-like glucan yielded large amounts of short-chain fatty acids (212.33 mM), especially butyric acid (12.64 mM). Thus, reuteran-like glucan could be used as a low-digestible and highly fermentable fiber for controlling blood glucose levels and prebiotic potential.


Assuntos
Glucanos , Prebióticos , Glucanos/análise , Fezes/química , Prebióticos/análise , Amido/química
7.
Ann Work Expo Health ; 67(4): 485-495, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-36715220

RESUMO

OBJECTIVES: Dust generated from wood processing comprises a heterogeneous mixture of inorganic and organic particles, including wood fragments, microorganisms, endotoxins, (1-3)-ß-d-glucans, and allergens. This study characterized exposure to wood dust and its determinants in the Mozambiquan wood processing industry. METHODS: A total of 124 personal inhalable samples, collected from a stratified random sample of 30 workers, were analysed for dust particulate, endotoxins, and (1-3)-ß-d-glucans. Mixed-effects models were developed to investigate significant exposure determinants. RESULTS: The geometric mean (GM) inhalable dust particulate concentrations were 3.29 mg m-3, 98 endotoxin units (EU) m-3, and 123 ng m-3 for (1-3)-ß-d-glucans. Significant predictors for higher particulate levels included machinery (GMR = 1.93), sawing (GMR = 2.80), carpentry (GMR = 2.77), or painting (GMR = 3.03) tasks. Lebombo-ironwood species was associated with higher dust particulate levels (GMR = 1.97). Determinants of endotoxin concentrations included working with dry wood and damp cleaning methods, which were associated with lower levels. Working in closed buildings (GMR = 3.10) and dry sweeping methods were associated with higher (1-3)-ß-d-glucan concentrations (GMR = 1.99). CONCLUSIONS: Work tasks in certain exposure groups (machinery, sawing, carpentry, painting), processing certain wood species (Lebombo-ironwood) and working in closed buildings were associated with higher exposures, whilst using dry wood and damp cleaning practices reduced exposure levels.


Assuntos
Poluentes Ocupacionais do Ar , Exposição Ocupacional , Humanos , Endotoxinas/análise , Glucanos/análise , Exposição Ocupacional/análise , Poluentes Ocupacionais do Ar/análise , Madeira/química , Exposição por Inalação/análise , Poeira/análise
8.
Nat Rev Microbiol ; 21(4): 248-259, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36266346

RESUMO

The fungal cell wall is essential for growth and survival, and is a key target for antifungal drugs and the immune system. The cell wall must be robust but flexible, protective and shielding yet porous to nutrients and membrane vesicles and receptive to exogenous signals. Most fungi have a common inner wall skeleton of chitin and ß-glucans that functions as a flexible viscoelastic frame to which a more diverse set of outer cell wall polymers and glycosylated proteins are attached. Whereas the inner wall largely determines shape and strength, the outer wall confers properties of hydrophobicity, adhesiveness, and chemical and immunological heterogeneity. The spatial organization and dynamic regulation of the wall in response to prevailing growth conditions enable fungi to thrive within changing, diverse and often hostile environments. Understanding this architecture provides opportunities to develop diagnostics and drugs to combat life-threatening fungal infections.


Assuntos
Glucanos , beta-Glucanas , Glucanos/análise , Glucanos/química , Glucanos/metabolismo , Parede Celular/metabolismo , Antifúngicos , beta-Glucanas/análise , beta-Glucanas/metabolismo , Quitina/análise , Quitina/química , Quitina/metabolismo , Proteínas Fúngicas/análise , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo
9.
Ann Work Expo Health ; 66(8): 967-973, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-35957588

RESUMO

Airborne concentrations of organic dust on animal farms are known to be very high. This dust is partly composed of microorganisms such as bacteria, fungi and their components [endotoxins, (1→3)-ß-d-glucans, mould allergens, mycotoxins], recognised as being responsible for numerous health effects. Several cross-sectional studies have measured levels of airborne bacteria, fungi and endotoxins on pig farms. However, the temporal dynamics of organic dust's components throughout the year have rarely been assessed, and airborne concentrations of (1→3)-ß-d-glucans and mould allergens remain poorly understood in these work environments. This longitudinal, four-season study measured cultivable fungi, endotoxins, (1→3)-ß-d-glucans, Aspergillus versicolor (AveX), Aspergillus fumigatus (Asp f1) and Alternaria sp (Alt a1) allergens on 31 pig farms in Switzerland. Results showed that exposure to AveX occurred in all four seasons. Total mean airborne concentration of endotoxins were between 3 and 4 times higher than the Swiss recommended limit value of 1000 EU m-3 and mean airborne concentrations of fungi were between 30 and 50 times higher than the Swiss recommended limit value of 1000 cfu m-3. Finally, accumulations of faecal matter on floors, humidity and dusty pathways were associated with increased concentrations of (1→3)-ß-d-glucans. In conclusion, pig farmers require better information about biological occupational risks, and measures to improve air quality should be implemented, especially in winter.


Assuntos
Poluentes Ocupacionais do Ar , Micotoxinas , Exposição Ocupacional , Microbiologia do Ar , Poluentes Ocupacionais do Ar/análise , Alérgenos , Animais , Bactérias , Estudos Transversais , Poeira/análise , Endotoxinas/análise , Fazendas , Fungos , Glucanos/análise , Exposição Ocupacional/análise , Suínos
10.
Work ; 73(1): 181-187, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35912760

RESUMO

BACKGROUND: Sewage treatment plant workers (STPs) are exposed to gaseous pollutants (H2S) and bioaerosols and their health is at risk. OBJECTIVE: The aim of the study was to evaluate exposures to dust, 1,3 Beta D Glucans, endotoxins and gaseous pollutants in different process plants and to provide suitable recommendations. METHODS: Gaseous pollutants and bioaerosols (inhalable dust, 1,3 beta D-glucans and endotoxins) were evaluated in two sewage treatment plants (STPs) of Ahmedabad city, India. The concentration of H2S, CO, CH4 and Cl2 were monitored in two process areas of STPs using real-time gas detectors. The dust, 1,3 beta D-glucans and endotoxins were evaluated as per standard methods. RESULTS: The mean concentration of H2S exceeded the permissible exposure limit of 10 ppm, whereas the concentration of other gaseous pollutants (CO, Cl2 and CH4) were below the permissible exposure limits of Indian Factories Act, 1948. The inhalable dust concentration was also within the permissible exposure limit of 10 mg/m3 as per Indian Factories Act, 1948. CONCLUSIONS: Significant exposures to gaseous and bioaerosols were found in the work environment of STPs. The paired t-test result showed a significant difference between two STPs for H2S, 1,3 beta D-Glucans and endotoxins. STPs were advised to reduce the exposure to H2S and bioaerosols as per CPCB guidelines applicable to India to prevent health effects.


Assuntos
Poluentes Ocupacionais do Ar , Poluentes Ambientais , Exposição Ocupacional , Poluentes Ocupacionais do Ar/análise , Poeira/análise , Endotoxinas/análise , Gases , Glucanos/análise , Humanos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Esgotos
11.
Methods Mol Biol ; 2542: 323-360, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36008676

RESUMO

The cell wall contains mannans and glucans that are recognized by the host immune system. In this chapter, we will describe the methods to isolate mannans and glucans from the C. albicans cell wall. In addition, we describe how to determine purity, molecular size, and structure of the mannans and glucans. We also detail how to prepare the carbohydrates for in vitro, ex vivo, or in vivo use by describing endotoxin removal (depyrogenation), derivatization, and labeling and evaluation of bioactivity.


Assuntos
Glucanos , Mananas , Candida albicans , Parede Celular/química , Glucanos/análise
12.
J Vis Exp ; (181)2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35435899

RESUMO

Glycogen particles are branched polysaccharides composed of linear chains of glucosyl units linked by α-1,4 glucoside bonds. The latter are attached to each other by α-1,6 glucoside linkages, referred to as branch points. Among the different forms of carbon storage (i.e., starch, ß-glucan), glycogen is probably one of the oldest and most successful storage polysaccharides found across the living world. Glucan chains are organized so that a large amount of glucose can quickly be stored or fueled in a cell when needed. Numerous complementary techniques have been developed over the last decades to solve the fine structure of glycogen particles. This article describes Fluorophore-Assisted Carbohydrate Electrophoresis (FACE). This method quantifies the population of glucan chains that compose a glycogen particle. Also known as chain length distribution (CLD), this parameter mirrors the particle size and the percentage of branching. It is also an essential requirement for the mathematical modeling of glycogen biosynthesis.


Assuntos
Glucanos , Glicogênio , Eletroforese , Glucanos/análise , Glucanos/química , Glucosídeos , Polissacarídeos
13.
Methods Mol Biol ; 2457: 151-165, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35349138

RESUMO

The deposition and turnover of callose (beta-1,3 glucan polymer) in the cell wall surrounding the neck regions of plasmodesmata (PD) controls the cell-to-cell diffusion rate of molecules and, therefore, plays an important role in the regulation of intercellular communication in plants.Here we describe a simple and fast in vivo staining procedure for the imaging and quantification of callose at PD. We also introduce calloseQuant, a plug-in for semiautomated image analysis and non-biased quantification of callose levels at PD using ImageJ.


Assuntos
Glucanos , Plasmodesmos , Compostos de Anilina , Glucanos/análise , Plasmodesmos/química , Coloração e Rotulagem
14.
Mikrochim Acta ; 189(3): 88, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35129697

RESUMO

The development of an intracellular metabolite imaging platform for live microorganisms has been a challenge in the study of microbes. Herein, we performed metabolite imaging in live microalgal cells using a graphene oxide (GO)/aptamer complex. The properties of the GO were characterized using dynamic light scattering (DLS) and atomic force microscopy (AFM), which were determined to have 140 ± 3 nm in mean diameter. An ATP-specific aptamer was mixed with GO to form a GO/aptamer complex, and the feasibility of the complex was tested in vitro. The high correlation between the fluorescence intensity and concentration of ATP was observed in the range 0-10 mM. Next, the feasibility of the complex was confirmed in vivo. Under both phototrophic and heterotrophic culture conditions, Euglena gracilis internalized the complex, and bright fluorescence was observed as the aptamer was bound to the target metabolite (ATP). The fluorescence intensity of cells was correlated to the ATP concentration in the cells. Imaging of dual intracellular metabolites (ATP and paramylon) was achieved by simply using two different aptamers (ATP-specific aptamer and paramylon-specific aptamer) together, showing the great potential of the complex as a dual-sensing/imaging platform. In addition, the GO/aptamer complex exhibited low cytotoxicity; the proliferation and viability of E. gracilis cells were not significantly affected by the complex. Our results suggested that this new imaging platform can be efficiently used for detecting dual intracellular metabolites in live microalgal cells.


Assuntos
Trifosfato de Adenosina/análise , Aptâmeros de Nucleotídeos/química , Euglena gracilis/química , Glucanos/análise , Grafite/química , Nanopartículas/química , Trifosfato de Adenosina/metabolismo , Técnicas Biossensoriais , Euglena gracilis/citologia , Euglena gracilis/metabolismo , Glucanos/metabolismo
15.
Carbohydr Polym ; 273: 118540, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560952

RESUMO

Linkage patterns and relaxation dynamics of baobab (Adansonia digitata) polysaccharides have been investigated by means of linkage analysis and rheometry. The fruit polysaccharide was mostly xylogalacturonan, with co-extracted α-glucan. The leaf polysaccharide consists predominantly of two domains, one branched at O-4 of the →2)-Rhap-(1→ residues and another branched at O-3 of the →4)-GalpA-(1→ backbone to single GlcpA-(1→ residues. Master curves of viscoelasticity of fruit polysaccharides manifested strong pH-dependency. At pH below the dissociation constant of galacturonic acid, dispersions showed liquid-like behaviour. In contrast, at neutral pH, a weak gel network formation was observed that destabilised rapidly under the influence of flow fields. The present work identifies xylogalacturonans from baobab fruit as polysaccharides with unique rheological characteristics that may point to new directions in food and pharmaceutical formulation.


Assuntos
Adansonia/química , Frutas/química , Pectinas/química , Folhas de Planta/química , Polissacarídeos/química , Glucanos/análise , Ácidos Hexurônicos/análise , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Pectinas/análise , Polissacarídeos/análise , Reologia/métodos
16.
Sci Rep ; 11(1): 13640, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210998

RESUMO

Euglena gracilis is widely utilized as food or supplement to promote human and animal health, as it contains rich nutrients. In this study, we administered spray-dried powder of E. gracilis and paramylon, ß-glucan stored in E. gracilis cells, to A4gnt knockout (KO) mice. A4gnt KO mice are a mutant mouse model that spontaneously develops gastric cancer through hyperplasia-dysplasia-adenocarcinoma sequence in the antrum of the stomach, and we observed the effects of E. gracilis and paramylon on the early involvements of A4gnt KO mice. Male and female 10-week-old A4gnt KO mice and their age-matched wildtype C57BL/6J mice were orally administered with 50 mg of E. gracilis or paramylon suspended in saline or saline as a control. After 3-week administration, animals were euthanatized and the stomach was examined histopathologically and immunohistochemically. Gene expression patterns of the stomach, which have been reported to be altered with A4gnt KO, and IgA concentration in small intestine were also analyzed with real-time PCR and ELISA, respectively. Administration of Euglena significantly reduced the number of stimulated CD3-positive T-lymphocytes in pyloric mucosa of A4gnt KO mice and tend to reduce polymorphonuclear leukocytes infiltration. Euglena administration further downregulated the expression of Il11 and Cxcl1 of A4gnt KO mice. Euglena administration also affected IgA concentration in small intestinal contents of A4gnt KO mice. Paramylon administration reduced the number of CD3-positive lymphocytes in pyloric mucosa of A4gnt KO mice, and downregulated the expressions of Il11 and Ccl2 of A4gnt KO mice. Although we found no significant effects on gross and microscopic signs of gastric dysplasia and cell proliferation, the present study suggests that the administration of Euglena and paramylon may ameliorate the early involvements of A4gnt mice through the effects on inflammatory reactions in the gastric mucosa. The cancer-preventing effects should be studied with long-term experiments until actual gastric cancer formation.


Assuntos
Anticarcinógenos/uso terapêutico , Euglena gracilis , Glucanos/uso terapêutico , N-Acetilglucosaminiltransferases/genética , Neoplasias Gástricas/prevenção & controle , Administração Oral , Animais , Anticarcinógenos/administração & dosagem , Anticarcinógenos/análise , Suplementos Nutricionais/análise , Euglena gracilis/química , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Glucanos/administração & dosagem , Glucanos/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
17.
World J Microbiol Biotechnol ; 37(7): 114, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34115218

RESUMO

Interspecific hybridization between Ganoderma lingzhi and G. applanatum was attempted through polyethylene glycol (PEG) induced fusion technique. The protoplast isolation procedure was simplified, and we obtained a significant number of protoplasts from both Ganoderma species. The number of protoplasts obtained was 5.27 ± 0.31 × 107/mL in G. lingzhi and 5.57 ± 0.49 × 106/mL in G. applanatum. Osmotic stabilizer NaCl (0.4 M) at pH 5.8 and enzymolysis time 3.5 h have supported high frequency of protoplast regeneration. G. lingzhi and G. applanatum regeneration frequency was 1.73 ± 0.04% and 0.23 ± 0.02%, respectively. 40% of PEG induced high number of protoplast fusion the regeneration frequency was 0.09% on a minimal medium. Two hundred fifty-two fusant colonies were isolated from the following four individual experiments. Among them, ten fusants showed the mycelial morphological difference compared to their parents and other fusant isolates. The fruiting body could be generated on oak sawdust and wheat bran substrate, and a few of them showed recombined morphology of the parental strains. The highest yield and biological efficacy (BE) were recorded in GF248, while least in GF244. The hybridity of the fusant was established based on mycelia, fruiting morphology, and PCR fingerprinting. ISSR and RAPD profile analysis of ten fusants and parents depicted that fusants contained polymorphic bands, which specified the rearrangement and deletion of DNA in the fusants. A Dendrogram was constructed based on the RAPD profile, and the clustering data exhibited two major clusters: cluster I included the G. lingzhi and Cluster II, including the G. applanatum and fusant lines. Total polysaccharide (α, ß and total glucan) content was compared with fusants and parental strains. The present study highlighted the efficient methods for protoplast isolation from Ganoderma species. PEG-induced fusants showed high polymorphic frequency index, while the phenotypic characters showed high similarity to G. applanatum. A significant difference was observed in the mushroom yield and its total polysaccharide between the fusants and parental strains.


Assuntos
Ganoderma/fisiologia , Glucanos/análise , Protoplastos/fisiologia , Meios de Cultura/química , Impressões Digitais de DNA , Fibras na Dieta/microbiologia , Ganoderma/química , Hibridização Genética , Polietilenoglicóis/química , Protoplastos/química , Quercus/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico
18.
Int J Biol Macromol ; 182: 207-216, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33831453

RESUMO

Arca subcrenata Lischke is a seafood with high nutritional value. In this study, we purified and characterized a novel water-soluble polysaccharide (ASPG-2) from Arca subcrenata with significant immunoregulatory effects and no apparent cell toxicity. ASPG-2 is a class of mixed-linkage α,ß-d-glucan backbones with α-linked side chains with a molecular weight of 4.39 × 105 Da. Its structure was characterized as a repeating unit consisting of (1 → 3)-ß-d-Glcp, (1 → 4)-α-d-Glcp, (1 → 4,6)-α-d-Glcp and (1 → 6)-α-d-Glcp. Using mouse RAW264.7 macrophages, we demonstrated that ASPG-2 exerted marked immunoregulatory effects by promoting the secretion of NO and increasing the phagocytosis of RAW264.7 cells in vitro. Moreover, flow cytometry analysis of the expression of the cell surface molecule CD86 revealed that ASPG-2 could polarize RAW264.7 cells into the M1 type. The immunomodulatory mechanism of ASPG-2 in macrophages was associated with the activation of the TLR4-MAPK/Akt-NF-κB signalling pathways. These results indicated that ASPG-2 might be researched and developed as a potential immunomodulatory agent or health product from marine organisms.


Assuntos
Arcidae/química , Glucanos/isolamento & purificação , Fagocitose/efeitos dos fármacos , Alimentos Marinhos/análise , Transdução de Sinais , Animais , Sequência de Carboidratos , Glucanos/análise , Glucanos/farmacologia , Imunomodulação , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Peso Molecular , NF-kappa B/metabolismo , Células RAW 264.7
19.
Carbohydr Polym ; 259: 117743, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33674003

RESUMO

The mature basal stipe of mushroom Coprinopsis cinerea loses wall extensibility. We found that an endo-ß-1,3-glucanase ENG from C. cinerea could restore mature basal stipe wall extensibility via pretreatment such that the ENG-pretreated basal stipe walls could be induced to extend by chitinase ChiIII. ENG pretreatment released glucose, laminaribiose, and 3-O-D-gentiobiose-D-glucose from the basal stipe walls, consistent with ENG-digested products of ß-1,6-branched ß-1,3-glucan. Different effects of endo-ß-1,3-glucanase ENG and exo-ß-1,3-glucanase EXG pretreatment on the structure, amount and ratio (ß-1,3-glucoside bonds to ß-1,6-glucoside bonds) of products from the basal stipe and the apical stipe cell walls, respectively, and on the cell wall extensibility and the cell wall ultra-architecture of the basal stipes were analyzed. All results demonstrate that the more accumulation and cross-linkage of ß-1,6-branched ß-1,3-glucan with wall maturation lead to loss of wall extensibility of the basal stipe regions compared to the apical stipe cell walls.


Assuntos
Agaricales/química , Parede Celular/química , Glucanos/análise , Agaricales/metabolismo , Sequência de Aminoácidos , Parede Celular/metabolismo , Quitinases/química , Quitinases/genética , Quitinases/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Dextranase/química , Dextranase/genética , Dextranase/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Espectrometria de Massas em Tandem
20.
J Dairy Res ; 88(1): 98-104, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33594965

RESUMO

In this research communication we evaluate the impact of the addition of prebiotic components (inulin, polydextrose, and modified starch, 40 g/l) as fat substitutes on the physicochemical characteristics, probiotic survival, and sensory acceptance of probiotic (Lacticaseibacillus casei 01, 108 CFU/ml) Greek yogurts during storage (7 °C, 28 d). All formulations had probiotic counts higher than 107 CFU/ml during storage and simulated gastrointestinal conditions (SGIC). The prebiotic components increased the probiotic survival to the enteric phase of the SGIC, with inulin producing the most pronounced effect. Inulin addition resulted in products with lower pH values and consistency and higher titratable acidity during storage, with negative impact on the sensory acceptance (flavor, texture, and overall impression) at the end of the storage period. Modified starch addition impacted negatively on the acceptance of the products (appearance, flavor, texture, and overall impression). Polydextrose addition resulted in products with lower consistency, but similar sensory acceptance to the full-fat yogurt. It can be concluded that it is possible to prepare potentially synbiotic Greek yogurts by desorption technique using L. casei as probiotic culture and inulin, polydextrose or modified starch as prebiotic components, with the utilization of polydextrose being advisable.


Assuntos
Substitutos da Gordura/análise , Prebióticos/análise , Probióticos/análise , Sensação , Iogurte/análise , Iogurte/microbiologia , Fenômenos Químicos , Comportamento do Consumidor , Glucanos/análise , Inulina/análise , Amido/análise
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