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1.
Bioresour Technol ; 413: 131482, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39270989

RESUMO

Sugarcane bagasse (SCB) has a recalcitrant structure, which hinders its component dismantling and subsequent high value utilization. Some organic solvents are favorable to dismantle lignocellulose, but their high viscosity prevents separation of components and reuse of solvents. Herein, ethylene glycol phenyl ether (EGPE)-acid system is used as an example to develop green and efficient methods to dismantle SCB, purify polysaccharides and lignin, and reuse solvents. Results show that dismantling SCB at 130 °C, 0.5 % H2SO4, and 100 min can obtain 85.5 % cellulose recovery, 94.1 % hemicellulose removal and 83.7 % lignin removal. Different molecular weight saccharides are separated by membranes filtration and centrifugation, and lignin recovered by antisolvent precipitation. The solvent recovered by distillation, achieving high dismantling efficiency of 89.2 % cellulose recovery, 94.1 % hemicellulose removal and 94.4 % lignin removal after four recycles. Results show a promising approach for the closed-loop process of dismantling lignocellulose, fractionating saccharides, and reusing solvents in high-viscosity systems.

2.
Carbohydr Polym ; 346: 122582, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39245481

RESUMO

The present study identified the protective effects of garlic oligo/poly-saccharides of different chain lengths against dextran sulfate sodium (DSS)-induced colitis in mice and elucidated the structure-function relationships. The results showed that oral intake of garlic oligo/poly-saccharides decreased disease activity index, reduced colon shortening and spleen enlargement, and ameliorated pathological damage in the mouse colon. The dysregulation of colonic pro/anti-inflammatory cytokines was significantly alleviated, accompanied by up-regulated antioxidant enzymes, blocked TLR4-MyD88-NF-κB signaling pathway, enhanced intestinal barrier integrity, and restored SCFA production. Garlic oligo/poly-saccharides also reversed gut microbiota dysbiosis in colitic mice by expanding beneficial bacteria and suppressing the growth of harmful bacteria. High-molecular-weight polysaccharides exhibited stronger alleviating effects on DSS-induced colitic symptoms in mice than low-molecular-weight oligo/poly-saccharides did, probably due to their greater ability to be fermented in the colon. Taken together, this study demonstrated the anti-inflammatory effects of garlic oligo/poly-saccharides and revealed that high-molecular-weight polysaccharide fractions were more effective in alleviating DSS-induced colitis.


Assuntos
Anti-Inflamatórios , Colite , Sulfato de Dextrana , Frutanos , Alho , Microbioma Gastrointestinal , Animais , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Alho/química , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Frutanos/farmacologia , Frutanos/química , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , Relação Estrutura-Atividade , Citocinas/metabolismo , Camundongos Endogâmicos C57BL , Peso Molecular , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Int J Pharm ; 664: 124626, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39208952

RESUMO

The manufacturing of tablets containing biologics exposes the biologics to thermal and shear stresses, which are likely to induce structural changes (e.g., aggregation and denaturation), leading to the loss of their activity. Saccharides often act as stabilizers of proteins in formulations, yet their stabilizing ability throughout solid oral dosage processing, such as tableting, has been barely studied. This work aimed to investigate the effects of formulation and process (tableting and spray-drying) variables on catalase tablets containing dextran, mannitol, and trehalose as potential stabilizers. Non-spray-dried and spray-dried formulations were prepared and tableted (100, 200, and 400 MPa). The enzymatic activity, number of aggregates, reflecting protein aggregation and structure modifications were studied. A principal component analysis was performed to reveal underlying correlations. It was found that tableting and spray-drying had a notable negative effect on the activity and number of aggregates formed in catalase formulations. Overall, dextran and mannitol failed to preserve the catalase activity in any unit operation studied. On the other hand, trehalose was found to preserve the activity during spray-drying but not necessarily during tableting. The study demonstrated that formulation and process variables must be considered and optimized together to preserve the characteristics of catalase throughout processing.


Assuntos
Catalase , Dextranos , Composição de Medicamentos , Excipientes , Manitol , Comprimidos , Trealose , Catalase/química , Trealose/química , Manitol/química , Dextranos/química , Excipientes/química , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , Secagem por Atomização , Agregados Proteicos
4.
Talanta ; 280: 126677, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142127

RESUMO

Taylor dispersion analysis (TDA) is a rapid and precise method for determining the hydrodynamic radius (RH) of various substances. We present a versatile TDA system with a flow-through sample injection device, two compact 3-in-1 detectors, and a high-voltage power supply. The 3D-printed detectors combine fluorimetry (FD), photometry (AD@255 nm), and contactless conductometry (C4D) in a single head, enabling simultaneous detection at one capillary window. Using bovine serum albumin (BSA) as a model analyte, we compare TDA with different detection methods. BSA labeled with fluorescein isothiocyanate (FITC) is analyzed in both pulse mode and capillary electrophoresis (CE) TDA. FD and AD detection yield similar RH values, except when FITC binds with small ions in the buffer. In phosphate buffer, C4D underestimates RH values by approximately 18 % due to BSA self-association. In Tris-based buffers, C4D values are 87%-96 % of AD values in pulse mode. With CE-TDA using Tris-CHES buffer, no statistical difference is found across all detections. The system is also applied to CE-TDA of various compounds, particularly charged saccharides. CE-TDA improves the accuracy of TDA results from C4D. We demonstrate the resolution of mixed C4D-TDA signals with assistance from FD and AD signals, successfully resolving gluconate peaks fully covered by another compound. The versatile system with 3-in-1 detection offers a powerful tool for TDA of mixtures and enhances sample throughput.


Assuntos
Fluoresceína-5-Isotiocianato , Fluorometria , Fotometria , Soroalbumina Bovina , Soroalbumina Bovina/química , Soroalbumina Bovina/análise , Fluorometria/métodos , Bovinos , Fotometria/métodos , Fluoresceína-5-Isotiocianato/química , Animais , Hidrodinâmica , Eletroforese Capilar/métodos
5.
Int J Food Microbiol ; 424: 110840, 2024 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-39126753

RESUMO

The biosynthetic machinery for cell wall polysaccharide (CWPS) formation in Lactococcus lactis and Lactococcus cremoris is encoded by the cwps locus. The CWPS of lactococci typically consists of a neutral rhamnan component, which is embedded in the peptidoglycan, and to which a surface-exposed side chain oligosaccharide or polysaccharide pellicle (PSP) component is attached. The rhamnan component has been shown for several lactococcal strains to consist of a repeating rhamnose trisaccharide subunit, while the side chain is diverse in glycan content, polymeric status and glycosidic linkage architecture. The observed structural diversity of the CWPS side chain among lactococcal strains is reflected in the genetic diversity within the variable 3' region of the corresponding cwps loci. To date, four distinct cwps genotypes (A, B, C, D) have been identified, while eight subtypes (C1 through to C8) have been recognized among C-genotype strains. In the present study, we report the identification of three novel subtypes of the lactococcal cwps C genotypes, named C9, C10 and C11. The CWPS of four isolates representing C7, C9, C10 and C11 genotypes were analysed using 2D NMR to reveal their unique CWPS structures. Through this analysis, the structure of one novel rhamnan, three distinct PSPs and three exopolysaccharides were elucidated. Results obtained in this study provide further insights into the complex nature and fascinating diversity of lactococcal CWPSs. This highlights the need for a holistic view of cell wall-associated glycan structures which may contribute to robustness of certain strains against infecting bacteriophages. This has clear implications for the fermented food industry that relies on the consistent application of lactococcal strains in mesophilic production systems.


Assuntos
Parede Celular , Genótipo , Lactococcus , Leite , Parede Celular/química , Lactococcus/genética , Lactococcus/isolamento & purificação , Lactococcus/classificação , Animais , Leite/microbiologia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo , Alimentos Fermentados/microbiologia , Polissacarídeos/metabolismo , Microbiologia de Alimentos
6.
J Am Soc Mass Spectrom ; 35(9): 2041-2055, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39140654

RESUMO

In this investigation, we detail the synthesis of silver nanoparticles (AgNPs) via a precise chemical vacuum deposition (CVD) methodology, aimed at augmenting the analytical performance of laser desorption/ionization mass spectrometry (LDI-MS) for the detection of low-molecular-weight analytes. Employing a precursor supply rate of 0.0014 mg/s facilitated the formation of uniformly dispersed AgNPs, characterized by SEM and AFM to have an average diameter of 33.5 ± 1.5 nm and a surface roughness (Ra) of 11.8 nm, indicative of their homogeneous coverage and spherical morphology. XPS and SEM-EDX analyses confirmed the metallic silver composition of the nanoparticles with Ag peak splitting, reflecting the successful synthesis of metallic Ag. Comparative analytical evaluation with traditional MALDI matrices revealed that AgNPs significantly reduce signal suppression, thereby enhancing the sensitivity and specificity of LDI-MS for low-molecular-weight compounds such as triglycerides, saccharides, amino acids, and carboxylic acids. Notably, the application of AgNPs demonstrated a superior linear response for triglyceride signals with regression coefficients surpassing 0.99, markedly outperforming conventional matrices. The study further extends into quantitative analysis through nanoparticle-based laser desorption/ionization (NALDI), where AgNPs exhibited enhanced ionization efficiency, characterized by substantially lower limits of detection (LOD) and quantification (LOQ) for tested standards. Particular attention was paid to lipids with a detailed examination of their fragmentation pathways. These results highlight the significant potential of AgNPs synthesized via CVD to transform the analytical detection and quantification of low-molecular-weight compounds using NALDI. This approach offers a promising avenue for expanding the scope of analytical applications in mass spectrometry and introducing innovative methodologies for enhanced precision and sensitivity.


Assuntos
Nanopartículas Metálicas , Prata , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Prata/química , Nanopartículas Metálicas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Aminoácidos/análise , Aminoácidos/química , Peso Molecular , Triglicerídeos/análise , Triglicerídeos/química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/análise , Limite de Detecção
7.
Angew Chem Int Ed Engl ; : e202412436, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39206505

RESUMO

The selective functionalization of carbohydrates holds a central position in synthetic carbohydrate chemistry, driving the ongoing quest for ideal approaches to manipulate these compounds. In this study, we introduce a general strategy that enables the regiodivergent functionalization of saccharides. The use of electron-deficient photoactive 4-tetrafluoropyridinylthio (SPyf) fragment as an adaptable activating group, facilitated efficient functionalization across all saccharide sites. More importantly, this activating group can be directly installed at the C1, C5 and C6 positions of biomass-derived carbohydrates in a single step and in a site-selective manner, allowing for the efficient and precision-oriented modification of unprotected saccharides and glycans.

8.
Bioanalysis ; 16(16): 849-861, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39023344

RESUMO

Aim: Bioanalytical assays to measure rhamnose, erythritol, lactulose and sucralose in human urine and plasma were developed to support an indomethacin challenge study for intestinal permeability assessment in healthy participants.Methods: The multi-sugar assays utilized 5-µl sample matrix and a simple chemical derivatization with acetic anhydride, followed by RPLC-MS/MS detection.Results: Rhamnose and erythritol quantification was established between 1.00-1,000 µg/ml in urine and 250-250,000 ng/ml in plasma. For lactulose and sucralose, dynamic ranges of 0.1-100 µg/ml (urine) and 25-25,000 ng/ml (plasma) were applied for biological measurements.Conclusion: This work helped overcome some of the common analytical challenges associated with the bioanalysis of mono- and disaccharides and achieved improved limits of quantification.


[Box: see text].


Assuntos
Permeabilidade , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Mucosa Intestinal/metabolismo , Ramnose/urina , Sacarose/análogos & derivados , Sacarose/urina , Lactulose/urina , Cromatografia Líquida de Alta Pressão , Eritritol/análogos & derivados , Eritritol/metabolismo , Eritritol/urina , Função da Barreira Intestinal
9.
J Hazard Mater ; 476: 134995, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38909468

RESUMO

To address two current issues in evaluating the toxicity of microplastics (MPs) namely, conflicting results due to species specificity and the ecological irrelevance of laboratory data, this study conducted a 10-day exposure experiment using a microalgal community comprising three symbiotic species. The experiment involved virgin and Benzo[a]pyrene-spiked micron-scale fibers and fragments made of polyethylene terephthalate (PET) and polypropylene (PP). The results showed that, from a physiological perspective, environmentally relevant concentrations of micron-scale MPs decreased saccharide accumulation in microalgal cells, as confirmed by ultrastructural observations. MPs may increase cellular energy consumption by obstructing cellular motility, interfering with nutrient uptake, and causing sustained oxidative stress. Additionally, MPs and adsorbed B[a]P induced DNA damage in microalgae, potentially further disrupting cellular energy metabolism. Ecologically, MPs altered the species abundance in microalgal communities, suggesting they could weaken the ecological functions of these communities as producers and affect ecosystem diversity and stability. This study marks a significant advancement from traditional single-species toxicity experiments to community-level assessments, providing essential insights for ecological risk assessment of microplastics and guiding future mechanistic studies utilizing multi-omics analysis.


Assuntos
Metabolismo Energético , Microalgas , Microplásticos , Microplásticos/toxicidade , Microalgas/efeitos dos fármacos , Microalgas/metabolismo , Metabolismo Energético/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Polipropilenos/toxicidade , Polipropilenos/química , Dano ao DNA/efeitos dos fármacos , Benzo(a)pireno/toxicidade , Benzo(a)pireno/metabolismo , Polietilenotereftalatos/química , Polietilenotereftalatos/toxicidade , Tamanho da Partícula , Estresse Oxidativo/efeitos dos fármacos
10.
Int J Biol Macromol ; 273(Pt 2): 133045, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38942666

RESUMO

This work was to investigate the effect of four prebiotic saccharides gum arabic (GA), fructooligosaccharide (FOS), konjac glucomannan (KGM), and inulin (INU) incorporation on the encapsulation efficiency (EE), physicochemical stability, and in vitro digestion of urolithin A-loaded liposomes (UroA-LPs). The regulation of liposomes on gut microbiota was also investigated by in vitro colonic fermentation. Results indicated that liposomes coated with GA showed the best EE, bioaccessibility, storage and thermal stability, the bioaccessibility was 1.67 times of that of UroA-LPs. The UroA-LPs coated with FOS showed the best freeze-thaw stability and transformation. Meanwhile, saccharides addition remarkably improved the relative abundance of Bacteroidota, reduced the abundances of Proteobacteria and Actinobacteria. The UroA-LPs coated with FOS, INU, and GA exhibited the highest beneficial bacteria abundance of Parabacteroides, Monoglobus, and Phascolarctobacterium, respectively. FOS could also decrease the abundance of harmful bacteria Collinsella and Enterococcus, and increase the levels of acetic acid, butyric acid and iso-butyric acid. Consequently, prebiotic saccharides can improve the EE, physicochemical stability, gut microbiota regulation of UroA-LPs, and promote the bioaccessibility of UroA, but the efficiency varied based on saccharides types, which can lay a foundation for the application of UroA in foods industry and for the enhancement of its bio-activities.


Assuntos
Microbioma Gastrointestinal , Lipossomos , Prebióticos , Microbioma Gastrointestinal/efeitos dos fármacos , Lipossomos/química , Polimerização , Cumarínicos/química , Cumarínicos/metabolismo , Fermentação
11.
Chemphyschem ; : e202400419, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38945838

RESUMO

Scanning probe microscopy (SPM), in particular at low temperature (LT) under ultra-high vacuum (UHV) conditions, offers the possibility of real-space imaging with resolution reaching the atomic level. However, its potential for the analysis of complex biological molecules has been hampered by requirements imposed by sample preparation. Transferring molecules onto surfaces in UHV is typically accomplished by thermal sublimation in vacuum. This approach however is limited by the thermal stability of the molecules, i. e. not possible for biological molecules with low vapour pressure. Bypassing this limitation, electrospray ionisation offers an alternative method to transfer molecules from solution to the gas-phase as intact molecular ions. In soft-landing electrospray ion beam deposition (ESIBD), these molecular ions are subsequently mass-selected and gently landed on surfaces which permits large and thermally fragile molecules to be analyzed by LT-UHV SPM. In this concept, we discuss how ESIBD+SPM prepares samples of complex biological molecules at a surface, offering controls of the molecular structural integrity, three-dimensional shape, and purity. These achievements unlock the analytical potential of SPM which is showcased by imaging proteins, peptides, DNA, glycans, and conjugates of these molecules, revealing details of their connectivity, conformation, and interaction that could not be accessed by any other technique.

12.
Food Res Int ; 187: 114392, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763654

RESUMO

Variations in cultivars and cultivation altitudes have significant impacts on tea flavour compounds however lack of comprehensive understanding. This study provided insights into differential accumulation of crucial flavour compounds in response to cultivars, cultivation altitudes, and processing. Twelve flavonoids (262.4 âˆ¼ 275.4 mg•g-1) and 20 amino acids (AAs) (56.5 âˆ¼ 64.8 mg•g-1) were comparative analyzed in 'Longjing 43' and 'Qunti' fresh leaves harvested at low (80 m, LA) and high (500 m, HA) altitudes. Additionally, an in-depth correlation unravelling of 31 alkaloids, 25 fatty acids, 31 saccharides, 8 organic acids, and 7 vitamins and flavonoids/AAs during green tea (GT) and black tea (BT) processing was performed. Enhenced flavonoid accumulation alongside higher AAs and saccharides in HA GT promoted a sweet/mellow flavour. Abundant flavonoids, AAs, and saccharides derivates in LA BT gave rise to a sweet aftertaste. The study presents an integrated illustration of major flavour compounds' differential accumulation patterns and their interrelations, providing new insights into the influence of cultivation conditions on tea flavour.


Assuntos
Altitude , Camellia sinensis , Flavonoides , Folhas de Planta , Chá , Folhas de Planta/química , Folhas de Planta/metabolismo , Flavonoides/análise , Chá/química , Camellia sinensis/química , Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/metabolismo , Paladar , Aminoácidos/análise , Aminoácidos/metabolismo , Manipulação de Alimentos/métodos , Aromatizantes/análise , Alcaloides/análise , Alcaloides/metabolismo
13.
Food Chem ; 454: 139805, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810442

RESUMO

The poor thermal stability and ion tolerance of whey protein hydrolysates (WPH) restrict its application in emulsions, while glycosylation shows potential benefits in improving WPH stability. However, the relationship between saccharides with different Mw and the glycosylation behavior of WPH rich in short peptides is unclear. In response, the effect of different saccharides on glycosylated WPH rich in short peptides and its emulsion stability were investigated. Grafted small Mw saccharides were more beneficial to the emulsion stability of WPH. Specifically, grafting xylose effectively inhibited 121 °C sterilization and 5 mM CaCl2-induced coalescence of WPH emulsion (687.50 nm) by comprehensively enhancing steric hindrance, conformational flexibility and electrostatic repulsion, and dissociating large aggregates into small aggregates. Conversely, grafting maltodextrin (30,590 Da) reduced thermal stability of WPH emulsion (4791.80 nm) by steric shielding and bridging flocculation. These findings provide new sights into glycosylation mechanism for WPH and achieving its application in nutritional emulsions.


Assuntos
Cálcio , Emulsões , Temperatura Alta , Hidrolisados de Proteína , Proteínas do Soro do Leite , Proteínas do Soro do Leite/química , Emulsões/química , Glicosilação , Hidrolisados de Proteína/química , Cálcio/química , Tamanho da Partícula
14.
Nano Lett ; 24(18): 5639-5646, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38668743

RESUMO

Structural complexity brings a huge challenge to the analysis of sugar chains. As a single-molecule sensor, nanopores have the potential to provide fingerprint information on saccharides. Traditionally, direct single-molecule saccharide detection with nanopores is hampered by their small size and weak affinity. Here, a carbon nitride nanopore device is developed to discern two types of trisaccharide molecules (LeApN and SLeCpN) with minor structural differences. The resolution of LeApN and SLeCpN in the mixture reaches 0.98, which has never been achieved in solid-state nanopores so far. Monosaccharide (GlcNAcpN) and disaccharide (LacNAcpN) can also be discriminated using this system, indicating that the versatile carbon nitride nanopores possess a monosaccharide-level resolution. This study demonstrates that the carbon nitride nanopores have the potential for conducting structure analysis on single-molecule saccharides.

15.
Bioorg Chem ; 147: 107388, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38678775

RESUMO

In this study, we investigated the potential of long-range fluorine-carbon J-coupling for determining the structures of deoxyfluorinated disaccharides. Three disaccharides, previously synthesized as potential galectin inhibitors, exhibited through-space fluorine-carbon J-couplings. In our independent conformational analysis of these disaccharide derivatives, we employed a combination of density functional theory (DFT) calculations and nuclear magnetic resonance (NMR) experiments. By comparing the calculated nuclear shieldings with the experimental carbon chemical shifts, we were able to identify the most probable conformers for each compound. A model comprising fluoromethane and methane molecules was used to study the relationship between molecular arrangements and intermolecular through-space J-coupling. Our study demonstrates the important effect of internuclear distance and molecular orientation on the magnitude of fluorine-carbon coupling. The experimental values for the fluorine-carbon through-space couplings (TSCs) of the disaccharides corresponded with values calculated for the most probable conformers identified by the conformational analysis. These results unlock the broader application of fluorine-carbon TSCs as powerful tools for conformational analysis of flexible molecules, offering valuable insights for future structural investigations.


Assuntos
Teoria da Densidade Funcional , Dissacarídeos , Flúor , Espectroscopia de Ressonância Magnética , Flúor/química , Dissacarídeos/química , Carbono/química , Configuração de Carboidratos , Conformação Molecular
16.
Int J Mol Sci ; 25(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38255883

RESUMO

In various life forms, fucose-containing glycans play vital roles in immune recognition, developmental processes, plant immunity, and host-microbe interactions. Together with glucose, galactose, N-acetylglucosamine, and sialic acid, fucose is a significant component of human milk oligosaccharides (HMOs). Fucosylated HMOs benefit infants by acting as prebiotics, preventing pathogen attachment, and potentially protecting against infections, including HIV. Although the need for fucosylated derivatives is clear, their availability is limited. Therefore, synthesis methods for various fucosylated oligosaccharides are explored, employing enzymatic approaches and α-L-fucosidases. This work aimed to characterise α-L-fucosidases identified in an alpaca faeces metagenome. Based on bioinformatic analyses, they were confirmed as members of the GH29A subfamily. The recombinant α-L-fucosidases were expressed in Escherichia coli and showed hydrolytic activity towards p-nitrophenyl-α-L-fucopyranoside and 2'-fucosyllactose. Furthermore, the enzymes' biochemical properties and kinetic characteristics were also determined. All four α-L-fucosidases could catalyse transfucosylation using a broad diversity of fucosyl acceptor substrates, including lactose, maltotriose, L-serine, and L-threonine. The results contribute insights into the potential use of α-L-fucosidases for synthesising fucosylated amino acids.


Assuntos
Camelídeos Americanos , Lactente , Animais , Humanos , Fucose , Metagenoma , alfa-L-Fucosidase/genética , Escherichia coli/genética , Fezes , Lactose
17.
Anal Chim Acta ; 1288: 342166, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38220298

RESUMO

BACKGROUND: As an essential compound in living organism, saccharides have attracted enormous attentions from scientists in various fields. Understanding the distribution of saccharides in various samples is of great scientific importance. However, the low signal response and lack of specific recognition technology of saccharides and the complex matrix of samples make the analysis of saccharides a very challenge task. Thus, the development of a simple and straightforward strategy for the analysis of saccharides would represent a great contribution to the field. RESULTS: In this study, by employing the sulfonyl functionalized magnetic dendritic mesoporous silica nanoparticles as the substrate, we develop an integrated platform for analysis of saccharides. The construction of the platform mainly relied on multi-functional boronic acid, which serves as separation and derivation ligands at the same time. In the general procedure, the boronic acid is first immobilized onto the surface of substrate, then the selective enrichment of saccharides can be realized via boronate affinity separation. Finally, by the rational choice of the solution, we are able to elute the labelled complex (boronic acid-saccharide) from the substrate, which can be direct subjected to HPLC-UV analysis. The reliable precision (<15 %), accuracy (80-100 %), reproducibility (<10 %), improved sensitivity (20x) and limited time-consuming (down to minutes) of the proposed platform are experimentally demonstrated. SIGNIFICANCE AND NOVELTY: The successful quantification of different saccharides (alditols, glucose) in real samples is achieved. The proposed strategy is not only straightforward and fast, but also avoid the requirement of special equipment. With these attractive features, we believe that this strategy will greatly prompt the analysis of saccharides in various samples (eg. food, pharmaceutics and biosamples).


Assuntos
Nanopartículas , Dióxido de Silício , Dióxido de Silício/química , Reprodutibilidade dos Testes , Carboidratos/análise , Ácidos Borônicos/química , Nanopartículas/química , Fenômenos Magnéticos
18.
Eur J Pharm Sci ; 192: 106625, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918545

RESUMO

Saccharides are a popular group of stabilizers in liquid, frozen and freeze dried protein formulations. The current work reviewed the stabilization mechanisms of three groups of saccharides: (i) Disaccharides, specifically sucrose and trehalose; (ii) cyclodextrins (CDs), a class of cyclic oligosaccharides; and (iii) dextrans, a class of polysaccharides. Compared to sucrose, trehalose exhibits a more pronounced preferential exclusion effect in liquid protein formulations, due to its stronger interaction with water molecules. However, trehalose obtains higher phase separation and crystallization propensity in frozen solutions, resulting in the loss of its stabilization function. In lyophilized formulations, sucrose has a higher crystallization propensity. Besides, its glass matrix is less homogeneous than that of trehalose, thus undermining its lyoprotectant function. Nevertheless, the hygroscopic nature of trehalose may result in high water absorption upon storage. Among all the CDs, the ß form is believed to have stronger interactions with proteins than the α- and γ-CDs. However, the stabilization effect, brought about by CD-protein interactions, is case-by-case - in some examples, such interactions can promote protein destabilization. The stabilization effect of hydroxypropyl-ß-cyclodextrin (HPßCD) has been extensively studied. Due to its amphiphilic nature, it can act as a surface-active agent in preventing interfacial stresses. Besides, it is a dual functional excipient in freeze dried formulations, acting as an amorphous bulking agent and lyoprotectant. Finally, dextrans, when combined with sucrose or trehalose, can be used to produce stable freeze dried protein formulations. A strong stabilization effect can be realized by low molecular weight dextrans. However, the terminal glucose in dextrans yields protein glycation, which warrants extra caution during formulation development.


Assuntos
Ciclodextrinas , Trealose , Trealose/química , Sacarose/química , Ciclodextrinas/química , Dextranos/química , Excipientes/química , Água/química , Liofilização
19.
Sci Total Environ ; 912: 168849, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38056638

RESUMO

Saccharides are ubiquitous organic compounds that are omnipresent in nature and are considered tracers of aerosol sources. Saccharides and hemicellulose were analyzed in the aerosols of two polluted regions (Allahabad, India and Sosnowiec, Poland). The chemical compositions of the compounds and their abundances were significantly different at the two sites. Levoglucosan was the most dominant saccharide present at both sites. Galactosan, anhydroglucofuranose, mannosan, glucose, arabitol, D-pinitol, sucrose, and trehalose were found in Allahabad samples in high abundance but were significantly lower than levoglucosan. Mannosan, galactosan, arabinose, glycerol, and sucrose were significant compounds in Sosnowiec after dominating levoglucosan. The major sources of saccharides present in the Allahabad aerosols are hardwood and agricultural waste-burning emissions, whereas those at Sosnowiec are attributed to the burning of softwood (mainly gymnosperm trees), pine needles, or sporadically grass during the winter. Further, the chemical characteristics of hemicellulose remnants present in ambient aerosol at the Indian and European sites were analyzed and discussed. At both locations, hemicellulose was found using methanolysis of the filter samples; however, its state of preservation was poor. We believe that the primary sources of hemicellulose remnants are incomplete wood burning, crop straw, grass burning, or plant debris. Relatively poor preservation is associated with partial hemicellulose degradation when exposed to elevated temperatures or due to the oxidation and microbial degradation of plant fragments.


Assuntos
Poluentes Atmosféricos , Material Particulado , Polissacarídeos , Material Particulado/análise , Poluentes Atmosféricos/análise , Europa (Continente) , Sacarose , Aerossóis/análise , Monitoramento Ambiental , Biomassa , Estações do Ano
20.
Int J Biol Macromol ; 258(Pt 2): 129034, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38151080

RESUMO

The impacts of four extraction techniques, including hot water, ultrasonic-assisted, complex enzyme-assisted and acid-assisted methods, on the morphological, physicochemical properties and bioactivities of Asparagus cochinchinensis (poly)saccharides (EACP, WACP, UACP, and AACP) were investigated and compared. The four samples were mainly composed of glucose, fructose, and galactose with molar ratios of 50.8:22.7:4.4 for WACP, 53.9:26.0:5.3 for UACP, 35.6:14.1:21.4 for AACP and 45.0:15.6:9.0 for EACP, respectively. The rheological result showed that ACPs were non-Newtonian fluids. EACP with high purity (97.65 %) had good DPPH, O2- and ABTS+ radical scavenging activities, and significantly promoted the proliferation of the RAW264.7 cells at low concentration. UACP had good Fe2+ chelating ability, radical (DPPH, O2- and OH) scavenging activities, which might be attributed to the existence of triple-helix structure. AACP had high yield, molecular weight (17,477.2 Da), high crystallinity (23.33 %), and good radical (OH and ABTS+) scavenging activities. All four significantly stimulated the transcript expression levels of TNF-α, IL-1ß and IL-6, as determined by RT-PCR. These results suggest that the exploitation and utilization of non-inulin (poly)saccharides extracted by ultrasonic-assisted, complex enzyme-assisted and acid-assisted extraction methods are potentially valuable as effective and natural immune adjuvants and antioxidants.


Assuntos
Antioxidantes , Benzotiazóis , Antioxidantes/química , Ácidos Sulfônicos , Peso Molecular , Polissacarídeos/química
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