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1.
J Agric Food Chem ; 72(23): 13415-13430, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38824655

RESUMO

This study aimed to investigate the hypothesis that dietary konjac glucomannan (KGM) could alleviate Salmonella typhimurium-induced colitis by modulating intestinal microbiota. Mice were fed an isocaloric and isofibrous diet supplemented with either 7% KGM or cellulose and were treated with 5 × 108 CFU of S. typhimurium. The results showed that KGM had an average molecular weight of 936 kDa and predominantly consisted of mannose and glucose at a molar ratio of 1:1.22. In vivo studies demonstrated that dietary KGM effectively mitigated colonic lesions, oxidative stress, disruption of tight junction protein 2 and occludin, and the inflammatory response induced by S. typhimurium. Moreover, KGM administration alleviated the dramatic upregulation of toll-like receptor 2 (TLR2) and phosphonuclear factor κB (NF-κB) protein abundance, induced by Salmonella treatment. Notably, dietary KGM restored the reduced Muribaculaceae and Lactobacillus abundance and increased the abundance of Blautia and Salmonella in S. typhimurium-infected mice. Spearman correlation analysis revealed that the gut microbiota improved by KGM contribute to inhibit inflammation and oxidative stress. These results demonstrated the protective effects of dietary KGM against colitis by modulating the gut microbiota and the TLR2-NF-κB signaling pathway in response to Salmonella infection.


Assuntos
Colite , Colo , Microbioma Gastrointestinal , Mananas , NF-kappa B , Salmonella typhimurium , Transdução de Sinais , Receptor 2 Toll-Like , Animais , Mananas/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Receptor 2 Toll-Like/metabolismo , Receptor 2 Toll-Like/genética , NF-kappa B/metabolismo , NF-kappa B/genética , Colo/microbiologia , Colo/metabolismo , Transdução de Sinais/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Colite/microbiologia , Colite/dietoterapia , Masculino , Humanos , Camundongos Endogâmicos C57BL , Fibras na Dieta/farmacologia , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Amorphophallus/química
2.
Int J Mol Sci ; 25(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38892275

RESUMO

We have previously performed preclinical studies with the oxidized mannan-conjugated peptide MOG35-55 (OM-MOG35-55) in vivo (EAE mouse model) and in vitro (human peripheral blood) and demonstrated that OM-MOG35-55 suppresses antigen-specific T cell responses associated with autoimmune demyelination. Based on these results, we developed different types of dendritic cells (DCs) from the peripheral blood monocytes of patients with multiple sclerosis (MS) or healthy controls presenting OM-MOG35-55 or MOG-35-55 to autologous T cells to investigate the tolerogenic potential of OM-MOG35-55 for its possible use in MS therapy. To this end, monocytes were differentiated into different DC types in the presence of IL-4+GM-CSF ± dexamethasone (DEXA) ± vitamin D3 (VITD3). At the end of their differentiation, the DCs were loaded with peptides and co-cultured with T cells +IL-2 for 4 antigen presentation cycles. The phenotypes of the DC and T cell populations were analyzed using flow cytometry and the secreted cytokines using flow cytometry or ELISA. On day 8, the monocytes had converted into DCs expressing the typical markers of mature or immature phenotypes. Co-culture of T cells with all DC types for 4 antigen presentation cycles resulted in an increase in memory CD4+ T cells compared to memory CD8+ T cells and a suppressive shift in secreted cytokines, mainly due to increased TGF-ß1 levels. The best tolerogenic effect was obtained when patient CD4+ T cells were co-cultured with VITD3-DCs presenting OM-MOG35-55, resulting in the highest levels of CD4+PD-1+ T cells and CD4+CD25+Foxp3+ Τ cells. In conclusion, the tolerance induction protocols presented in this work demonstrate that OM-MOG35-55 could form the basis for the development of personalized therapeutic vaccines or immunomodulatory treatments for MS.


Assuntos
Células Dendríticas , Tolerância Imunológica , Esclerose Múltipla , Glicoproteína Mielina-Oligodendrócito , Humanos , Glicoproteína Mielina-Oligodendrócito/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Esclerose Múltipla/imunologia , Esclerose Múltipla/terapia , Esclerose Múltipla/tratamento farmacológico , Tolerância Imunológica/efeitos dos fármacos , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/farmacologia , Adulto , Feminino , Mananas/farmacologia , Masculino , Diferenciação Celular/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Células Cultivadas , Pessoa de Meia-Idade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Citocinas/metabolismo
3.
Int J Biol Macromol ; 272(Pt 1): 132739, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825290

RESUMO

A stable Madhuca indica oil-in-water nanoemulsion (99-210 nm, zeta potential: > - 30 mV) was produced employing Tween 20 (surfactant) and Transcutol P (co-surfactant) (3:1). The nanoemulsion (oil: Smix = 3:7, 5:5, and 7:3) were subsequently incorporated into oxcarbazepine-loaded carboxymethylxanthan gum (DS = 1.23) dispersion. The hydrogel microspheres were formed using the ionic gelation process. Higher oil concentration had a considerable impact on particle size, drug entrapment efficiency, and buoyancy. The maximum 92 % drug entrapment efficiency was achieved with the microspheres having oil: Smix ratio 5:5. FESEM study revealed that the microspheres were spherical in shape and had an orange peel-like surface roughness. FTIR analysis revealed a hydrogen bonding interaction between drug and polymer. Thermal and x-ray examinations revealed the transformation of crystalline oxcarbazepine into an amorphous form. The microspheres had a buoyancy period of 7.5 h with corresponding release of around 83 % drug in 8 h in simulated stomach fluid, governed by supercase-II transport mechanism. In vivo neurobehavioral studies on PTZ-induced rats demonstrated that the microspheres outperformed drug suspension in terms of rotarod retention, number of crossings, and rearing activity in open field. Thus, Madhuca indica oil-in-water nanoemulsion-entrapped carboxymethyl xanthan gum microspheres appeared to be useful for monitoring oxcarbazepine release and managing epileptic seizures.


Assuntos
Mananas , Microesferas , Animais , Ratos , Mananas/química , Hidrogéis/química , Tamanho da Partícula , Epilepsia/tratamento farmacológico , Masculino , Portadores de Fármacos/química , Emulsões , Convulsões/tratamento farmacológico , Liberação Controlada de Fármacos , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Anticonvulsivantes/química , Anticonvulsivantes/farmacologia , Galactose/análogos & derivados
4.
Sci Rep ; 14(1): 14015, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890382

RESUMO

Optimized production of Aspergillus niger ATCC 26011 endo-ß-mannanase (ManAn) on copra meal resulted in 2.46-fold increase (10,028 U/gds). Purified ManAn (47 kDa) showed high affinity towards guar gum (GG) as compared to konjac gum and locust bean gum with Km 2.67, 3.25 and 4.07 mg/mL, respectively. ManAn efficiently hydrolyzed GG and liberated mannooligosaccharides (MOS). Changes occurring in the rheological and compositional aspects of GG studied using Differential scanning calorimetry (DSC), Thermal gravimetric analysis (TGA) and X-ray diffraction (XRD) revealed increased thermal stability and crystallinity of the partially hydrolyzed guar gum (PHGG). Parametric optimization of the time and temperature dependent hydrolysis of GG (1% w/v) with 100 U/mL of ManAn at 60 °C and pH: 5.0 resulted in 12.126 mg/mL of mannotetraose (M4) in 5 min. Enhanced growth of probiotics Lactobacilli and production of short chain fatty acids (SCFA) that inhibited enteropathogens, confirmed the prebiotic potential of PHGG and M4.


Assuntos
Aspergillus niger , Galactanos , Mananas , Oligossacarídeos , Gomas Vegetais , Prebióticos , beta-Manosidase , Mananas/química , Mananas/metabolismo , Gomas Vegetais/química , Galactanos/química , Aspergillus niger/enzimologia , Oligossacarídeos/química , Hidrólise , beta-Manosidase/metabolismo , beta-Manosidase/química , Concentração de Íons de Hidrogênio , Ácidos Graxos Voláteis/metabolismo , Difração de Raios X , Temperatura , Lactobacillus/metabolismo , Probióticos
5.
Int J Biol Macromol ; 272(Pt 2): 132934, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38862320

RESUMO

Guar gum (GG) as a polymer biopolymer is widely used in the field of bio-based packaging. However, its poor mechanical properties, barrier properties and high viscosity greatly hinder its use as an effective packaging material. Therefore, this study introduced CPTES to improve the mechanical (16.58-27.39 MPa) and tensile properties (26.80 %-30.67 %). The FTIR and XRD results indicated a strong interaction between the biofilm fractions modified by CPTES, CPTES bound to the hydroxyl groups on GG and formed a dense polysiloxane network through adsorption and grafting. OM and AFM reflect a denser and flatter film structure on the surface of the G30 film, which has the best film formation. Based on this, the pH of the solution was further adjusted to reach an alkaline environment, disrupting the intermolecular binding through electrostatic repulsion. The rheological behavior indicates that the viscosity and viscoelasticity of film solution gradually decrease with the increase in pH. OM and AFM results show that the G30/8 film has the best compact properties, while the nonporous compact film structure further improves the mechanical, barrierand and thermodynamic properties of the film. Accordingly, the findings of this study had a certain value for regulating the low viscoelasticity of GG emulsion and enhancing the stability of film formation.


Assuntos
Galactanos , Mananas , Gomas Vegetais , Gomas Vegetais/química , Galactanos/química , Mananas/química , Concentração de Íons de Hidrogênio , Viscosidade , Silanos/química , Reologia , Resistência à Tração
6.
Carbohydr Polym ; 339: 122202, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823898

RESUMO

Interactions among multi-component play a critical role in modulating the foaming properties of aerated foods. This study evaluated the mechanisms of synergistic improvement of gellan gum (GEG) and guar gum (GUG) on the foaming properties of soy protein isolate (SPI)-based complex. The results showed that the GEG/GUG ratio was closely related to the intermolecular interactions of SPI-based ternary complex and the dynamical changing of its foaming properties. The SPI/GEG/GUG ternary complex with a GEG/GUG ratio of 2/3 exhibited the highest foamability (195 %) and comparable foam stability (99.17 %), which were 32.95 % and 2.99 % higher than that of SPI/GEG binary complex. At this ratio, GUG promoted the interactions between SPI and GEG, and bound to complex's surface through hydrogen bonding, resulting in the increase of particle size and surface charge, and the decrease of surface hydrophobicity. Although this reduced the diffusion of complex onto the air/water interface, it increased permeation rate and molecular rearrangement behavior, which were the potential mechanisms to improve the foaming properties. Additionally, the synergistic effect of GEG and GUG also enhanced the elastic strength and solid characteristics of foam systems. This study provided a theoretical guidance for the targeted modulation of foaming properties of multi-component aerated foods.


Assuntos
Galactanos , Mananas , Gomas Vegetais , Polissacarídeos Bacterianos , Proteínas de Soja , Gomas Vegetais/química , Galactanos/química , Proteínas de Soja/química , Mananas/química , Polissacarídeos Bacterianos/química , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Ligação de Hidrogênio
7.
Carbohydr Polym ; 339: 122268, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823931

RESUMO

The influence of locust bean gum (LBG) galactomannans (GMs) molecular weight (Mw) to assemble microparticulate systems was evaluated, and carriers for deep lung delivery were developed. A commercial batch of LBG with a mannose/galactose (M/G) ratio of 2.4 (batch 1) was used to study the influence of different microwave partial acid hydrolysis conditions on carbohydrate composition, glycosidic linkages, and aqueous solutions viscosity. The microwave treatment did not affect the composition, presenting 4-Man (36-42 %), 4,6-Man (27-35 %), and T-Gal (24-25 %) as the main glycosidic linkages. Depolymerization led to a viscosity reduction (≤0.005 Pa·s) with no major impact on polysaccharide debranching. The structural composition of the LBG galactomannans were further elucidated with sequence-specific proteins using carbohydrate microarray technologies. A second batch of LBG (M/G 3.3) was used to study the impact of GMs with different Mw on microparticle assembling, characteristics, and insulin release kinetics. The low-Mw GMs microparticles led to a faster release (20 min) than the higher-Mw (40 min) ones, impacting the release kinetics. All microparticles exhibited a safety profile to cells of the respiratory tract. However, only the higher-Mw GMs allowed the assembly of microparticles with sizes suitable for this type of administration.


Assuntos
Galactose , Mananas , Peso Molecular , Gomas Vegetais , Mananas/química , Galactose/química , Galactose/análogos & derivados , Gomas Vegetais/química , Humanos , Pulmão/metabolismo , Portadores de Fármacos/química , Tamanho da Partícula , Viscosidade , Insulina/química , Insulina/administração & dosagem , Liberação Controlada de Fármacos , Galactanos/química , Manose/química , Animais
8.
Carbohydr Polym ; 339: 122266, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823930

RESUMO

Konjac glucomannan (KG) is a dietary fiber hydrocolloid derived from Amorphophallus konjac tubers and is widely utilized as a food additive and dietary supplement. As a health-conscious choice, purified KG, along with konjac flour and KG-infused diets, have gained widespread acceptance in Asian and European markets. An overview of the chemical composition and structure of KG is given in this review, along with thorough explanations of the processes used in its extraction, production, and purification. KG has been shown to promote health by reducing glucose, cholesterol, triglyceride levels, and blood pressure, thereby offering significant weight loss advantages. Furthermore, this review delves into the extensive health benefits and pharmaceutical applications of KG and its derivatives, emphasizing its prebiotic, anti-inflammatory, and antitumor activities. This study highlights how these natural polysaccharides can positively influence health, underscoring their potential in various biomedical applications.


Assuntos
Amorphophallus , Mananas , Mananas/química , Mananas/isolamento & purificação , Humanos , Amorphophallus/química , Animais , Fibras na Dieta/análise , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Suplementos Nutricionais , Prebióticos , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia
9.
Mycoses ; 67(6): e13756, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38886163

RESUMO

BACKGROUND: Serum galactomannan (GM) testing is essential for diagnosing invasive aspergillosis (IA), particularly in immunocompromised individuals. The global lack of on-site GM testing capacities necessitates cost-effective alternatives, such as .the clarus Aspergillus GM enzyme immunoassay prototype (clarus AGM prototype). METHODS: This single-centre, cross-sectional study compared the diagnostic performance of the clarus AGM prototype (IMMY, Norman, Oklahoma) with the serological gold standard (=Platelia AGM assay; Bio-Rad, Marnes-la-Cocquette, France). IA was classified according to modified 2020 EORTC/MSG consensus and 2024 FUNDICU criteria. In total, 300 prospectively (May-Dec 2023) and retrospectively (2012-2015) collected samples were included. RESULTS: Among 300 samples from 232 patients, 49 (16%) were classified as proven (n = 1) or probable IA (n = 48). In non-IA cases (n = 250), one patient was classified as possible IA. With the manufacturer recommended cut-off of ≥0.2, sensitivity and specificity of the clarus AGM prototype were 27% (13/49; 95% confidence interval [CI]: 15%-41%) and 99% (248/250; 95% CI: 97%-100%), respectively, while sensitivity and specificity were 78% and 79% when using the optimised Youden's cut-off of 0.0045 ODI. ROC curve analysis demonstrated an area under the curve (AUC) of 0.829 (95% CI: 0.760-0.898) for the clarus AGM prototype in distinguishing between proven/probable IA and non-IA. The AUC for the Platelia AGM was 0.951 (95% CI: 0.909-994). Spearman's correlation analysis showed a weak correlation between the two assays (0.382; p < .001). CONCLUSIONS: The weak correlation between the clarus AGM prototype and Platelia AGM highlights the need for further investigation into the clinical performance of the clarus AGM prototype, giving the different antigen epitopes addressed.


Assuntos
Aspergillus , Galactose , Técnicas Imunoenzimáticas , Aspergilose Pulmonar Invasiva , Mananas , Sensibilidade e Especificidade , Humanos , Mananas/sangue , Galactose/análogos & derivados , Aspergilose Pulmonar Invasiva/diagnóstico , Técnicas Imunoenzimáticas/métodos , Estudos Transversais , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Estudos Retrospectivos , Aspergillus/isolamento & purificação , Aspergillus/imunologia , Adulto , Estudos Prospectivos , Antígenos de Fungos/sangue , Idoso de 80 Anos ou mais , Adulto Jovem , Curva ROC
10.
Carbohydr Polym ; 340: 122244, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38858017

RESUMO

This study introduces a novel multi-functional double-layer intelligent packaging. It focuses on developing a dual-function system capable of real-time monitoring and freshness preservation. Specifically, cellulose nanocrystalline (CNC) was obtained through acid hydrolysis, and then CNC/soybean protein isolate (CNC/SPI) complex colloid particles were prepared via antisolvent method. These particles served as stabilizers to prepare oil-in-water (O/W) cinnamon essential oil Pickering emulsion (CSCEO). The CSCEO was then integrated into the emulsified hydrophobic layer of a konjac glucomannan (Kgm) matrix through intermolecular hydrogen bonding. Finally, alginate (Alg) matrix containing alizarin (Al) as an indicator was added to construct the bilayer structure using a layer-by-layer casting strategy. The inner layer Alg/Al was the pH/NH3-responsive indicator layer, while the outer layer Kgm/CSCEO acted as the high-barrier bacteriostatic layer. The obtained dual-function, double-layer film (Alg/Al-Kgm/CSCEO), which possesses a sensitive, reversible and rapid response towards pH/NH3, shows exceptional antibacterial and antioxidant properties, as well as excellent mechanical property, light-blocking capability and hydrophobicity. For monitoring and maintaining the actual freshness of shrimp, such a bilayer packaging displays smallest change of ∆E and TVB-N (18.65 mg/100 g) even after 72 h, which further highlighting its potential in enhancing food safety and extending shelf life.


Assuntos
Alginatos , Antibacterianos , Embalagem de Alimentos , Mananas , Alimentos Marinhos , Alginatos/química , Embalagem de Alimentos/métodos , Mananas/química , Antibacterianos/química , Animais , Antioxidantes/química , Conservação de Alimentos/métodos , Interações Hidrofóbicas e Hidrofílicas , Penaeidae/química , Proteínas de Soja/química , Concentração de Íons de Hidrogênio , Escherichia coli/efeitos dos fármacos
11.
Carbohydr Res ; 541: 109150, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788560

RESUMO

Aim of the study was to optimize and produce beta-mannanase at fermenter scale by using cheaper minimal media. Increased production of beta-mannanase from Microbacterium camelliasinensis CIAB417 was achieved by heterologous expression in E. coli BL21 (DE3). The scale-up production of beta-mannanase was optimized from shake flask to 5-L fermenter. The cost-effective minimal media (M9+e) without any vitamins was found to be most effective and optimized for culturing the cells. The same media displayed no significant fluctuation in the pH while culturing the cells for the production of beta-mannanase both at shake flask and fermenter level. Additionally, E. coli cells were able to produce similar amount of dry cell weight and recombinant beta-mannanase both in the presence of micro and macro-oxygen environment. The optimized media was demonstrated to show no significant drop in pH throughout the recombinant protein production process. In one litre medium, 2.0314 g dry weight of E. coli cells yielded 1.8 g of purified recombinant beta-mannanase. The purified enzyme was lyophilized and demonstrated to hydrolyse locust bean gum to release mannooligosaccharides.


Assuntos
Escherichia coli , Fermentação , Proteínas Recombinantes , beta-Manosidase , beta-Manosidase/metabolismo , beta-Manosidase/genética , beta-Manosidase/biossíntese , beta-Manosidase/química , Escherichia coli/metabolismo , Escherichia coli/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Mananas/metabolismo , Mananas/química , Mananas/biossíntese , Reatores Biológicos , Concentração de Íons de Hidrogênio , Aerobiose , Galactanos/metabolismo , Galactanos/biossíntese , Galactanos/química , Meios de Cultura/química , Meios de Cultura/metabolismo , Gomas Vegetais/química , Gomas Vegetais/metabolismo , Actinobacteria/enzimologia , Actinobacteria/metabolismo , Actinobacteria/genética , Hidrólise
12.
N Biotechnol ; 82: 75-84, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-38750817

RESUMO

Natural biopolymers become increasingly attractive as bio-based alternatives to petrol-based rheological modifiers, especially in personal care applications. However, many polysaccharides exhibit undesired properties in cosmetic applications such as limited viscosifying characteristics, unpleasant sensory properties, or incompatibility with certain formulation compounds. Here, a comprehensive rheological analysis of non-decorated acetan-like heteroexopolysaccharides derived from two Kozakia baliensis strains was performed in selected surfactant formulations. The results were compared to native xanthan gum and a genetically engineered xanthan variant, Xan∆gumFGL, which lacks any acetyl- and pyruvyl moieties and whose rheological properties are unaffected by saline environments. All four polysaccharides displayed a highly similar rheological performance in the non-ionic surfactant lauryl glucoside, while the rheological properties differed in amphoteric and anionic surfactants cocamidopropyl betaine and sodium laureth sulfate due to minor changes in side chain composition. Polysaccharide precipitation was observed in the presence of the cationic surfactant. Nevertheless, the native heteroexopolysaccharide derived from K. baliensis LMG 27018 shows significant potential as a salt-independent rheological modifier compared to the genetically engineered Xan∆gumFGL variant. In addition, blends of heteroexopolysaccharides from K. baliensis and several galactomannans displayed synergistic effects which were comparable to native xanthan gum-galactomannan blends. This study shows that heteroexopolysaccharides of K. baliensis are capable of further extending the portfolio of bio-based rheological modifiers.


Assuntos
Galactose , Mananas , Polissacarídeos Bacterianos , Reologia , Tensoativos , Mananas/química , Galactose/análogos & derivados , Galactose/química , Tensoativos/química , Polissacarídeos Bacterianos/química , Glicosaminoglicanos/química , Glicosaminoglicanos/metabolismo
13.
Int J Biol Macromol ; 271(Pt 1): 132369, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750846

RESUMO

Curcumin and epigallocatechin gallate have the disadvantage of low aqueous solubility and first-pass metabolism, resulting in limited bioavailability. This work aimed to enhance oral bioavailability by forming gastric pH-stable shellac nanoparticles containing curcumin and epigallocatechin gallate using locust bean gum by anti-solvent precipitation (CESL-NP). The nanoparticles were characterized by their particle size, morphology, zeta potential, gastric pH stability, release profile, drug loading, and entrapment efficiency. The findings showed that a network of hydrolyzed shellac, locust bean gum, curcumin, and epigallocatechin gallate successfully entrapped individual particles inside a complex system. The morphological investigation of the CESL-NP formulation using FESEM, TEM, and AFM revealed the presence of spherical particles. FTIR, DSC, and XRD analysis revealed that curcumin and epigallocatechin gallate were amorphous due to their bond interactions with the matrix. Streptozotocin-treated mice, upon treatment with CESL-NP, showed kidney and pancreatic improvements with normalized kidney hypertrophy index and histopathology, maintained biochemical parameters, increased beta cell count, and a 38.68-fold higher blood glucose level inhibition were observed when compared to free-(CUR + EGCG). This research affirms that the shellac-locust bean gum complex shows potential for the sustained oral delivery of curcumin and epigallocatechin gallate, specifically for treating diabetic nephropathy.


Assuntos
Catequina , Curcumina , Nefropatias Diabéticas , Galactanos , Mananas , Nanopartículas , Gomas Vegetais , Animais , Curcumina/farmacologia , Curcumina/química , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Gomas Vegetais/química , Galactanos/química , Galactanos/farmacologia , Camundongos , Nanopartículas/química , Mananas/química , Mananas/farmacologia , Nefropatias Diabéticas/tratamento farmacológico , Portadores de Fármacos/química , Diabetes Mellitus Experimental/tratamento farmacológico , Masculino , Estreptozocina , Modelos Animais de Doenças , Tamanho da Partícula , Liberação Controlada de Fármacos
14.
Int J Biol Macromol ; 271(Pt 1): 132333, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754686

RESUMO

The fabrication of scaffolds capable of the sustained release of the vascular endothelial growth factor (VEGF) to promote angiogenesis for a long time remains a challenge in tissue engineering. Here, we report a facile approach for effectively fabricating a bioactive scaffold that gradually releases VEGF to promote angiogenesis. The scaffold was fabricated by coating polydopamine (PDA) on a konjac glucomannan (KGM) scaffold, followed by the surface immobilization of VEGF with PDA. The resulting VEGF-PDA/KGM scaffold, with a porous and interconnected microstructure (392 µm pore size with 84.80 porosity), combined the features of long-term biodegradability (10 weeks with 51 % degradation rate), excellent biocompatibility, and sustained VEGF release for up to 21 days. The bioactive VEGF-PDA/KGM scaffold exhibited multiple angiogenic activities over time, as confirmed by in vivo and in vitro experiments. For example, the scaffold significantly promoted the attachment and proliferation of human umbilical vein endothelial cells and the formation of vascular tubes in vitro. Moreover, the in vivo results demonstrated the formation and maturation of blood vessels after subcutaneous implantation in rats for four weeks. This promising strategy is a feasible approach for producing bioactive materials that can induce angiogenesis in vivo. These findings provide a new avenue for designing and fabricating biocompatible and long-term biodegradable scaffolds for sustained VEGF release to facilitate angiogenesis.


Assuntos
Preparações de Ação Retardada , Células Endoteliais da Veia Umbilical Humana , Indóis , Mananas , Neovascularização Fisiológica , Polímeros , Alicerces Teciduais , Fator A de Crescimento do Endotélio Vascular , Indóis/química , Indóis/farmacologia , Polímeros/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Mananas/química , Mananas/farmacologia , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Alicerces Teciduais/química , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Preparações de Ação Retardada/farmacologia , Ratos , Porosidade , Proliferação de Células/efeitos dos fármacos , Ratos Sprague-Dawley , Liberação Controlada de Fármacos , Masculino , Angiogênese
15.
Int J Biol Macromol ; 271(Pt 2): 132585, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38810849

RESUMO

Benefiting from the tissue-like mechanical properties, conductive hydrogels have emerged as a promising candidate for manufacturing wearable electronics. However, the high water content within hydrogels will inevitably freeze at subzero temperature, causing a degradation or loss of functionality, which severely prevent their practical application in wearable electronics. Herein, an anti-freezing hydrogel integrating high conductivity, superior stretchability, and robust adhesion was fabricated by dissolving choline chloride and gallium in gelatin/guar gum network using borax as the cross-linker. Based on the synergistic effect of dynamic borate ester bonds and hydrogen bonds, the hydrogel exhibited rapid self-healing property and excellent fatigue resistance. Profiting from these fascinating characteristics, the hydrogel was assembled as strain sensor to precisely detect various human activities with high strain sensitivity and fast response time. Meanwhile, the hydrogel was demonstrated high sensitivity and rapid response to temperature, which can be used as thermal sensor to monitor temperature. Moreover, the conductive hydrogel was encapsulated into supercapacitors with high areal capacitance and favorable cycle stability. Importantly, the flexible sensor and supercapacitors still maintain stable sensing performance and good electrochemical performance even at subzero temperature. Therefore, our work broaden hydrogels application in intelligent wearable devices and energy storage in extreme environments.


Assuntos
Condutividade Elétrica , Gelatina , Hidrogéis , Dispositivos Eletrônicos Vestíveis , Hidrogéis/química , Gelatina/química , Congelamento , Gomas Vegetais/química , Capacitância Elétrica , Mananas/química , Humanos , Metais/química
16.
Int J Biol Macromol ; 271(Pt 2): 132711, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38815942

RESUMO

Biobased materials are expanding dramatically in various industrial applications due to their unique intrinsic properties. In this study, various chemical functionalization procedures were used to synthesize guar gum, a naturally occurring polysaccharide-based polyurea, and its iodine complexes. Firstly, guar gum was subjected to tosylation reaction using p-toluene sulphonyl chloride to introduce tosyl moieties in the polymer chain with the degree of substitution (DS) ranging between 0.16 and 1.54. Sample having the highest degree of tosyl moiety was further reacted with tris(2-aminoethyl) amine to produce 6-deoxy-6-tris(2-aminoethyl) amine derivative via nucleophilic substitution reaction to impart amino functional groups. The degree of substitution in 6-deoxy-6-tris(2-aminoethyl) amine derivative was found to be 0.59. 6-deoxy-6-tris(2-aminoethyl) amine derivative was reacted with different diisocyanates (Toluene-2,4-diisocyanate (TDI), 1,6-diisocyanatohexane (HMDI)) to produce guar gum based polyurea. Iodine complexes of the resulting polyurea were prepared by reacting with different iodinating agents. Different chemical reactions, formation of polyurea and its iodine complexes were thoroughly analyzed by different analytical techniques such as FT-IR, NMR, elemental analysis, XRD, UV-Vis spectroscopy, and a reaction scheme has been proposed. Morphological and rheological characteristics were analyzed by SEM and viscosity measurement. Thermal analysis was carried out by TGA and DSC studies. Finally, by examining the complex's UV-Vis spectra, the iodine release characteristics from polyurea­iodine complexes were investigated.


Assuntos
Galactanos , Iodo , Mananas , Gomas Vegetais , Polímeros , Gomas Vegetais/química , Galactanos/química , Mananas/química , Iodo/química , Polímeros/química , Polímeros/síntese química , Técnicas de Química Sintética
17.
Int J Biol Macromol ; 271(Pt 2): 132733, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821298

RESUMO

The Gleditsia sinensis Lam. pods (GSP) are consistently discarded as waste after saponin extraction due to a lack of industrial or high-value utilization. Herein, the hemicelluloses were extracted from two varieties of GSP and subjected to comprehensive characterization. The molar mass of DMSO-soluble hemicelluloses (53.3-66.0 kDa) was higher compared to that of alkali-soluble ones (24.9-32.6 kDa). The presence of minimal acetyl substitution (3.85-4.49 %) on xylan was unequivocally confirmed. NMR spectroscopic analysis indicated that the hemicelluloses in GSP predominantly consist of a 1,4-ß-ᴅ-Xyl backbone with arabinose substituents at O-3 and 4-O-methyl-α-ᴅ-GlcA substituents at O-2 of the xylose residues. p-Coumaric acid substitution also occurred on the 1,4-ß-ᴅ-Xyl backbone. Hydrothermal treatment significantly reduced the hemicelluloses' relative molar mass and produced 7-10 % xylo-oligosaccharides. Furthermore, the moderately degraded hemicelluloses exhibited significantly enhanced biological activity. Finally, the incorporation of the moderately degraded hemicelluloses imparted the galactomannan film with exceptional antioxidant properties (81.1 % DPPH scavenging activity), while negligibly affecting its transparency. Our study's findings will contribute to a comprehensive understanding of the structural and biochemical properties of hemicellulose in waste G. sinensis pods, thereby facilitating their enhanced utilization in industrial applications.


Assuntos
Galactose , Gleditsia , Mananas , Polissacarídeos , Polissacarídeos/química , Mananas/química , Galactose/análogos & derivados , Galactose/química , Gleditsia/química , Peso Molecular , Antioxidantes/química
18.
Int J Biol Macromol ; 271(Pt 1): 132537, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821806

RESUMO

Cyanidin-3-O-glucoside (C3G) is a type of water-soluble flavonoid compound that is abundantly found in fruits and vegetables. C3G possesses numerous biological activities, however, it is prone to breakdown under environmental conditions. To overcome these issues, we developed nano-nutriosome (NS) carriers created by vortex-mixing and probe-sonication techniques for C3G encapsulation in which the phospholipid and Nutriose® FB06 were chosen as carrier material, and guar gum (GG) as a coating material to formulate a unilamellar and multicompartment structure. This study aimed to develop and evaluate C3G-loaded nano-nutriosomes coated by GG (GG-C3G-NS) for improving physicochemical stability, antioxidant activity, cellular uptake, and controlled release properties. The C3G-NS and GG-C3G-NS are nanosized (143.47 to 154.13 nm), with high encapsulation efficiency (>93.31 %). The NS carriers successfully encapsulated C3G which was confirmed by transmission electron microscopy, differential scanning calorimetry, and Fourier transform infrared spectroscopy. C3G showed more stability in storage, thermal, pH, ionic, and oxidative conditions. Furthermore, the NS exhibited a better-controlled release of C3G in different food stimulant conditions and in vitro release study. Additionally, NS systems enhanced cellular uptake and showed no cytotoxicity. Overall, GG-NS could be a promising nanocarrier for improving the stability, controlled release, and antioxidant activity of bioactive compounds.


Assuntos
Antocianinas , Antioxidantes , Galactanos , Mananas , Gomas Vegetais , Gomas Vegetais/química , Galactanos/química , Antocianinas/química , Antocianinas/farmacologia , Mananas/química , Antioxidantes/química , Antioxidantes/farmacologia , Portadores de Fármacos/química , Nanopartículas/química , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio
19.
J Environ Sci (China) ; 144: 1-14, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38802222

RESUMO

Nanoscale zero-valent iron (NZVI), which has the advantages of small particle size, large specific surface area, and high reactivity, is often injected into contaminated aquifers in the form of slurry. However, the prone to passivation and agglomeration as well as poor stability and mobility of NZVI limit the further application of this technology in fields. Therefore, sulfided NZVI loaded on reduced graphene oxide (S-NZVI/rGO) and guar gum (GG) with shear-thinning properties as stabilizers were used to synthesize S-NZVI/rGO@GG slurries. SEM, TEM, and FT-IR confirmed that the dispersion and anti-passivation of NZVI were optimized in the coupled system. The stability and mobility of the slurry were improved by increasing the GG concentration, enhancing the pH, and decreasing the ionic strength and the presence of Ca2+ ions, respectively. A modified advection-dispersion equation (ADE) was used to simulate the transport experiments considering the strain and physicochemical deposition/release. Meanwhile, colloidal filtration theory (CFT) demonstrated that Brownian motion plays a dominant role in the migration of S-NZVI/rGO@GG slurry, and the maximum migration distance can be increased by appropriately increasing the injection rate. Extended-Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory showed that the excellent stability and migration of S-NZVI/rGO@GG slurry mainly came from the GG spatial forces. This study has important implications for the field injection of S-NZVI/rGO@GG slurry. According to the injection parameters, the injection range of S-NZVI/rGO@GG slurry is effectively controlled, which lays the foundation for the promotion of application in actual fields.


Assuntos
Galactanos , Grafite , Ferro , Mananas , Gomas Vegetais , Grafite/química , Gomas Vegetais/química , Galactanos/química , Mananas/química , Ferro/química , Modelos Químicos , Nanopartículas Metálicas/química
20.
Carbohydr Res ; 540: 109145, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759341

RESUMO

The cell wall of endophytic strain Rathayibacter oskolensis VKM Ac-2121T (family Microbacteriaceae, class Actinomycetes) was found to contain neutral and acidic glycopolymers. The neutral polymer is a block-type rhamnomannan partially should be substitutied by xylose residues, [→2)-α-[ß-D-Xylp-(1 â†’ 3)]-D-Manp-(1 â†’ 3)-α-D-Rhap-(1→]∼30 [→2)-α-D-Manp-(1 â†’ 3)-α-D-Rhap-(1→]∼45. The acidic polymer has branched chain, bearing lactate and pyruvate residues, →4)-α-D-[S-Lac-(2-3)-α-L-Rhap-(1 â†’ 3)]-D-Manp-(1 â†’ 3)-α-D-[4,6-R-Pyr]-D-Galp-(1 â†’ 3)-ß-D-Glcp-(1 â†’. The structures of both glycopolymers were not described in the Gram-positive bacteria to date. The glycopolymers were studied by chemical and NMR spectroscopic methods. The results of this study provide new data on diversity of bacterial glycopolymers and may prove useful in the taxonomy of the genus Rathayibacter and for understanding the molecular mechanisms of interaction between plants and plant endophytes.


Assuntos
Parede Celular , Xilose , Parede Celular/química , Parede Celular/metabolismo , Xilose/química , Xilose/metabolismo , Ácido Láctico/química , Ácido Láctico/metabolismo , Ácido Pirúvico/química , Ácido Pirúvico/metabolismo , Mananas/química , Sequência de Carboidratos , Actinobacteria/química , Actinobacteria/metabolismo , Ramnose/química , Polissacarídeos Bacterianos/química , Polissacarídeos/química , Actinomycetales/química , Actinomycetales/metabolismo
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