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1.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 40: e20240017, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39043473

RESUMO

OBJECTIVE: This work is aimed to formulate and evaluate Mucoadhesive Microspheres contain Amoxicillin for the effective use in the treatment of H.Pylori. METHODS: Microspheres were prepared using Emulsification-cross linking technique. To this guar gum (GG) and sodium alginate (SA) was dissolved in 200 ml of water and allowed to swell for 24 h at room temperature. And separately chitosan (CH) was dissolved in 2% (v/v) glacial acetic acid and this also kept for 24 h to swell or dissolve properly. After 24 h this swelled mixture was mixed under magnetic stirrer (Remi, India) at specific stirring rate for 1 h in order to find homogeneous mass of both the gum. Then slurry of chitosan also was homogenized for half an hour. The drug, Amoxicillin (1g) was then added to the chitosan solution and mixed homogeneously. RESULTS: The aim of the study was to formulate and evaluate microspheres, for SR of the chosen drug. The particle size of microspheres was in the range of 200-500 µ, maximum mucoadhesive property observed was 57.41% for Optimized formulation F-9, Drug release 68.52% till 8 h, and the maximum entrapment was 94.87% for F-9 formulation. The work also aims to study various parameters affecting the behavior of microspheres in oral dosage form. CONCLUSION: Drugs with short half life that are absorbed from the gastrointestinal tract (GIT) are eliminated rapidly from the blood flow. To avoid this, the oral SR was developed as this formulation released the drug slowly into the GIT and maintained a stable drug concentration in the serum for a longer duration of time.


Assuntos
Alginatos , Amoxicilina , Quitosana , Mananas , Microesferas , Gomas Vegetais , Amoxicilina/administração & dosagem , Amoxicilina/farmacocinética , Amoxicilina/química , Quitosana/química , Gomas Vegetais/química , Mananas/química , Alginatos/química , Helicobacter pylori/efeitos dos fármacos , Galactanos/química , Tamanho da Partícula
2.
Nutrients ; 16(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38999863

RESUMO

The emptying rate of specific nutrients in enteral formulas is poorly understood, despite the importance of controlling the emptying rate in tube-fed patients. Because of their viscosity, thickened formulas are widely used to avoid gastric reflux and reduce the burden on caregivers. This study examined how thickeners in enteral formulas affected the gastric emptying rates of proteins and carbohydrates. A semi-dynamic gastric model was used to prepare and digest test enteral formulas that contained either no thickeners or agar (0.2%). The amounts of protein and carbohydrates in each emptied aliquot were determined, and the emptying rate was calculated. We found that agar accelerated protein emptying, and an exploratory experiment with agar (0.5%) suggested the possibility of concentration dependence. Additionally, experiments using gellan gum (0.08%), guar gum (0.2%), or carrageenan (0.08%, 0.2%) suggested that protein emptying could vary depending on the thickener type and that carrageenan might slow it. These results could help with the appropriate selection of thickeners added to liquid foods based on the patient's metabolic profile to manage nutrition, not only for tube-fed patients but also for those with oropharyngeal dysphagia or diabetes.


Assuntos
Proteínas Alimentares , Nutrição Enteral , Alimentos Formulados , Galactanos , Esvaziamento Gástrico , Mananas , Gomas Vegetais , Esvaziamento Gástrico/efeitos dos fármacos , Nutrição Enteral/métodos , Humanos , Mananas/farmacologia , Mananas/administração & dosagem , Viscosidade , Galactanos/farmacologia , Proteínas Alimentares/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Carragenina , Ágar , Polissacarídeos Bacterianos/farmacologia , Modelos Biológicos
3.
Carbohydr Res ; 542: 109204, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38981322

RESUMO

The hexasaccharide arabinan domain of Mycobacterial Arabinogalactan was provided with the versatile methodology toward ß-selective arabinofuranosylation directed by B(C6F5)3, demonstrating the effectiveness of the ß-arabinofuranosylation strategy. Derivatization of the amino moiety at the reducing end are essential prerequisites for elucidating the biosynthetic pathway and conjugating of this compound to a protein carrier for vaccine generation.


Assuntos
Galactanos , Galactanos/química , Galactanos/síntese química , Oligossacarídeos/síntese química , Oligossacarídeos/química , Sequência de Carboidratos , Mycobacterium/química , Polissacarídeos
4.
Fish Shellfish Immunol ; 151: 109753, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38977111

RESUMO

Bimetallic (Au/Ag) nanoparticles (BNPs) have shown enhanced antibacterial activity compared to their monometallic counterparts. Sulfated galactans (SG) are a naturally occurring polymer commonly found in red seaweed Gracilaria fisheri. They are biocompatible and biodegradable and environmentally friendly. In this study, we utilized SG in combination with BNPs to develop composite materials that potentially enhance antibacterial activity against shrimp pathogens Vibrio parahaemolyticus and Vibrio harveyi, compared to BNPs or SG alone. BNPs were coated with sulfated galactan (SGBNPs) and characterized using UV-vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, zeta potential, and transmission electron microscopy (TEM). UV-vis spectroscopy analysis revealed that the surface plasmon peaks of BNPs and SGBNPs appeared at 530 nm and 532 nm, respectively. Zeta potential measurements showed that SGBNPs had a negative charge of -32.4 mV, while the BNPs solution had a positive charge of 38.7 mV. TEM images demonstrated the spherical morphology of both BNPs and SGBNPs with narrow size distributions (3-10 nm). Analysis of the FTIR spectra indicated that SG maintained its backbone structure in SGBNPs, but some functional groups were altered. Notably, SGBNPs showed superior antimicrobial and antibiofilm activities against V. parahaemolyticus and V. harveyi compared to SG and BNPs. Furthermore, treatment with SGBNPs significantly down-regulated the expression of virulence-related genes (toxR, cpsQ, and mfpA) for V. parahaemolyticus 3HP compared to the respective control, bacteria treated with BNPs or SG. Diets supplemented with SGBNPs, BNPs, or SG showed no detrimental impact on the growth of shrimp Penaeus vannamei. Shrimp fed with SGBNPs-supplemented feed showed significantly higher survival rates than those fed with BNPs-supplemented feed when infected with 3HP after being on the supplemented feed for seven days and a subsequent number of fifteen days. These findings collectively demonstrate the benefit of using SG capped Au-Ag BNPs as an antibacterial agent for the prevention and control of Vibrio sp. Infection in shrimp while reducing the risk of environmental contamination.


Assuntos
Galactanos , Nanopartículas Metálicas , Penaeidae , Vibrio parahaemolyticus , Vibrio , Animais , Vibrio parahaemolyticus/efeitos dos fármacos , Vibrio parahaemolyticus/fisiologia , Penaeidae/imunologia , Nanopartículas Metálicas/química , Galactanos/química , Galactanos/farmacologia , Vibrio/efeitos dos fármacos , Vibrio/fisiologia , Antibacterianos/farmacologia , Antibacterianos/química , Prata/farmacologia , Prata/química , Ouro/química , Ouro/farmacologia
5.
Environ Geochem Health ; 46(8): 298, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980518

RESUMO

Grass carp intestinal waste-mediated biosynthesized nanosilver (AgNPs) was valorized using guaran and zeolite matrices, resulting in AgNPs-guaran, AgNPs-zeolite, and AgNPs-guaran -zeolite composites. The valorized products were examined using Environmental Scanning Electron Microscopy, Energy Dispersive X-ray analysis and X-ray Diffraction analysis to confirm uniform dispersion and entrapment of AgNPs within the matrixes. These valorized products were evaluated for their efficacy in detoxifying the ubiquitous and toxic hexavalent chromium (Cr6+) in aquatic environments, with Anabas testudineus exposed to 2 mg l-1 of Cr6+ for 60 days. Remarkable reduction of Cr6+ concentration to 0.86 ± 0.007 mg l-1 was achieved with AgNPs-guaran-zeolite composite, indicating successful reclamation of contaminated water and food safety assurance. Consistency in results was further corroborated by minimal stress-related alterations in fish physiological parameters and integrated biomarker response within the experimental group treated with the AgNPs-guaran-zeolite composite. Despite observed chromium accumulation in fish tissues, evidence of physiological stability was apparent, potentially attributable to trivalent chromium accumulation, serving as an essential nutrient for the fish. Additionally, the challenge study involving Anabas testudineus exposed to Aeromonas hydrophila exhibited the lowest cumulative mortality (11.11%) and highest survival rate (87.5%) within the same experimental group. The current study presents a novel approach encompassing the valorization of AgNPs for Cr6+ detoxification under neutral to alkaline pH conditions, offering a comprehensive framework for environmental remediation.


Assuntos
Biomarcadores , Cromo , Nanopartículas Metálicas , Prata , Poluentes Químicos da Água , Zeolitas , Animais , Cromo/química , Zeolitas/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Prata/química , Prata/toxicidade , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Hidrogéis/química , Bioacumulação , Inativação Metabólica , Galactanos , Mananas , Gomas Vegetais
6.
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
7.
Int J Biol Macromol ; 273(Pt 1): 132825, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38852724

RESUMO

Glycyrrhiza glabra Linn (liquorice) has been widely used for therapeutic purposes to treat digestive disorders, immunomodulatory disorders, inflammatory disorders, diabetes, viral infections, and cancer. Liquorice contains a wide variety of bioactive compounds, including glycyrrhizin, flavonoids, and terpenoids. Several factors compromise their therapeutic efficacy, such as poor pharmacokinetic profiles and physicochemical properties. Therefore, to improve its overall effectiveness, liquorice solid dispersion (LSD) was incorporated into biopolymer-based guar gum-grafted-2-acrylamido-2-methylpropane sulfonic acid (Guar gum-g-AMPS) hydrogels designed for controlled delivery via the oral route and characterized. The qualitative analysis of LSD revealed 51 compounds. Hydrogel structural properties were assessed for their effect on swelling and release. The highest swelling ratio (6413 %) and drug release (84.12 %) occurred at pH 1.2 compared to pH 7.4 (swelling ratio of 2721 % and drug release of 79.36 %) in 48 h. The hydrogels exhibited high porosity (84.23 %) and biodegradation (9.30 % in 7 days). In vitro hemolysis tests have demonstrated the compatibility of the hydrogel with blood. CCK-8 assay confirmed the biocompatibility of the synthesized hydrogel using osteoblasts and RIN-m5f cells. LSD exhibited good anti-inflammatory activity when loaded into hydrogels after being subjected to protein denaturation experiments. Moreover, LSD-loaded hydrogels have good antioxidant and antibacterial properties.


Assuntos
Preparações de Ação Retardada , Liberação Controlada de Fármacos , Galactanos , Hidrogéis , Mananas , Gomas Vegetais , Gomas Vegetais/química , Galactanos/química , Galactanos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Mananas/química , Mananas/farmacologia , Glycyrrhiza/química , Humanos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Portadores de Fármacos/química , Antibacterianos/farmacologia , Antibacterianos/química , Linhagem Celular
8.
Int J Biol Macromol ; 273(Pt 1): 132824, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38857736

RESUMO

Herein, we synthesized hydrogel films from crosslinked polyethylene oxide (PEO) and guar gum (GG) which can offer hydrophilicity, antibacterial efficacy, and neovascularization. This study focuses on synthesis and material/biological characterization of rosemary (RM) and citric acid (CA) loaded PEO/GG hydrogel films. Scanning Electron Microscopy images confirmed the porous structure of the developed hydrogel film matrix (PEO/GG) and the dispersion of RM and CA within it. This porous structure promotes moisture adsorption, cell attachment, proliferation, and tissue layer formation. Fourier Transform Infrared Spectroscopy (FTIR) further validated the crosslinking of the PEO/GG matrix, as confirmed by the appearance of C-O-C linkage in the FTIR spectrum. PEO/GG and PEO/GG/RM/CA revealed similar degradation and release kinetics in Dulbecco's Modified Eagle Medium, Simulated Body Fluid, and Phosphate Buffer Saline (degradation of ∼55 % and release of ∼60 % RM in 168 h.). The developed hydrogel film exhibited a zone of inhibition against Escherichia. coli (2 mm) and Staphylococcus. aureus (9 mm), which can be attributed to the presence of RM in the hydrogel film. Furthermore, incorporating CA in the hydrogel film promoted neovascularization, as confirmed by the Chorioallantoic Membrane Assay. The developed RM and CA-loaded PEO/GG-based hydrogel films offered suitable in-vitro properties that may aid in potential wound healing applications.


Assuntos
Antibacterianos , Liberação Controlada de Fármacos , Galactanos , Hidrogéis , Mananas , Gomas Vegetais , Polietilenoglicóis , Mananas/química , Galactanos/química , Gomas Vegetais/química , Polietilenoglicóis/química , Hidrogéis/química , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Cinética , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Membrana Corioalantoide/efeitos dos fármacos , Portadores de Fármacos/química
9.
Int J Biol Macromol ; 273(Pt 2): 133061, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38866272

RESUMO

Secondary lymphedema is a chronic and incurable disease lacking satisfactory therapeutic drugs. It primarily results from lymphatic vessel dysfunction resulting from factors such as tumor-related surgery, injury, or infection. Promoting lymphangiogenesis and lymphatic vessel remodeling is crucial for restoring tissue fluid drainage and treating secondary lymphedema. In this study, we discovered that the oral administration of a type-II arabinogalactan (CAPW-1, molecular weight: 64 kDa) significantly promoted lymphangiogenesis and alleviated edema in mice with secondary lymphedema. Notably, the tail diameter of the CAPW-1200 group considerably decreased in comparison to that of the lymphedema group, with an average diameter difference reaching 0.98 mm on day 14. CAPW-1 treatment also reduced the average thickness of the subcutaneous area in the CAPW-1200 group to 0.37 mm (compared with 0.73 mm in the lymphedema group). It also facilitated the return of injected indocyanine green (ICG) from the tail tip to the sciatic lymph nodes, indicating that CAPW-1 promoted lymphatic vessel remodeling at the injury site. In addition, CAPW-1 enhanced the proliferation and migration of lymphatic endothelial cells. This phenomenon was associated with the activation of the toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) signaling pathway, thereby promoting the expression of vascular endothelial growth factor-C (VEGF-C), which can be abolished using a TLR4 antagonist. Despite these findings, CAPW-1 did not alleviate the symptoms of lymphedema or restore lymphatic drainage in VEGFR3flox/flox/Prox1-CreERT2 mice. In summary, CAPW-1 alleviates secondary lymphedema by promoting lymphangiogenesis and lymphatic vessel remodeling through the activation of the TLR4/NF-κB/VEGF-C signaling pathway, indicating its potential as a therapeutic lymphangiogenesis agent for patients with secondary lymphedema.


Assuntos
Galactanos , Linfangiogênese , Vasos Linfáticos , Linfedema , Receptor 4 Toll-Like , Animais , Linfangiogênese/efeitos dos fármacos , Camundongos , Linfedema/tratamento farmacológico , Linfedema/metabolismo , Linfedema/etiologia , Vasos Linfáticos/efeitos dos fármacos , Vasos Linfáticos/metabolismo , Galactanos/farmacologia , Galactanos/química , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , NF-kappa B/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Masculino
10.
PLoS Genet ; 20(6): e1011127, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829907

RESUMO

The cell envelope fortifies bacterial cells against antibiotics and other insults. Species in the Mycobacteriales order have a complex envelope that includes an outer layer of mycolic acids called the mycomembrane (MM) and a cell wall composed of peptidoglycan and arabinogalactan. This envelope architecture is unique among bacteria and contributes significantly to the virulence of pathogenic Mycobacteriales like Mycobacterium tuberculosis. Characterization of pathways that govern envelope biogenesis in these organisms is therefore critical in understanding their biology and for identifying new antibiotic targets. To better understand MM biogenesis, we developed a cell sorting-based screen for mutants defective in the surface exposure of a porin normally embedded in the MM of the model organism Corynebacterium glutamicum. The results revealed a requirement for the conserved σD envelope stress response in porin export and identified MarP as the site-1 protease, respectively, that activate the response by cleaving the membrane-embedded anti-sigma factor. A reporter system revealed that the σD pathway responds to defects in mycolic acid and arabinogalactan biosynthesis, suggesting that the stress response has the unusual property of being induced by activating signals that arise from defects in the assembly of two distinct envelope layers. Our results thus provide new insights into how C. glutamicum and related bacteria monitor envelope integrity and suggest a potential role for members of the σD regulon in protein export to the MM.


Assuntos
Membrana Celular , Parede Celular , Corynebacterium glutamicum , Ácidos Micólicos , Fator sigma , Parede Celular/metabolismo , Parede Celular/genética , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Ácidos Micólicos/metabolismo , Fator sigma/metabolismo , Fator sigma/genética , Membrana Celular/metabolismo , Estresse Fisiológico , Porinas/metabolismo , Porinas/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Galactanos/metabolismo , Regulação Bacteriana da Expressão Gênica , Peptidoglicano/metabolismo
11.
Sci Total Environ ; 946: 174085, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38908596

RESUMO

Coalbed methane (CBM) presents a promising energy source for addressing global energy shortages. Nonetheless, challenges such as low gas production from individual wells and difficulties in breaking gels at low temperatures during extraction hinder its efficient utilization. Addressing this, we explored native microorganisms within coal seams to degrade guar gum, thereby enhancing CBM production. However, the underlying mechanisms of biogenic methane production by synergistic biodegradation of lignite and guar gum remain unclear. Research results showed that the combined effect of lignite and guar gum enhanced the production, yield rate and concentration of biomethane. When the added guar gum content was 0.8 % (w/w), methane production of lignite and guar gum reached its maximum at 561.9 mL, which was 11.8 times that of single lignite (47.3 mL). Additionally, guar gum addition provided aromatic and tryptophan proteins and promoted the effective utilization of CC/CH and OCO groups on the coal surface. Moreover, the cooperation of lignite and guar gum accelerated the transformation of volatile fatty acids into methane and mitigated volatile fatty acid inhibition. Dominant bacteria such as Sphaerochaeta, Macellibacteroides and Petrimonas improved the efficiency of hydrolysis and acidification. Electroactive microorganisms such as Sphaerochaeta and Methanobacterium have been selectively enriched, enabling the establishment of direct interspecies electron transfer pathways. This study offers valuable insights for increasing the production of biogenic CBM and advancing the engineering application of microbial degradation of guar gum fracturing fluid. Future research will focus on exploring the methanogenic capabilities of lignite and guar gum in in-situ environments, as well as elucidating the specific metabolic pathways involved in their co-degradation.


Assuntos
Biodegradação Ambiental , Carvão Mineral , Galactanos , Mananas , Metano , Gomas Vegetais , Gomas Vegetais/metabolismo , Mananas/metabolismo , Galactanos/metabolismo , Metano/metabolismo
12.
An Acad Bras Cienc ; 96(3): e20230073, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38896737

RESUMO

In this study, the Box-Behnken experimental planning was used to optimize the extraction of polysaccharides from the cell wall of Rhizopus microspore var. oligosporus, with analysis of the quantitative effects of parameters pH, temperature and extraction time for polysaccharide yield. The optimal conditions for extraction were determined by the regression equation and evaluation of the response surface graphs, which indicated: pH 13, temperature of 120ºC and time of 60 min, with maximum yield around 18.5%. Fourier transform infrared spectroscopy analysis indicated typical polysaccharide signals. Nuclear magnetic resonance spectroscopy and monosaccharide analysis indicated a ß(1,3) ß(1,6) glucogalactan. The polysaccharide exhibited an average molecular weight of 120 kDa and a polymerization degree of 741. Antioxidant assays in vitro revealed the potential of polysaccharide in elimination of ABTS+ radical and hydroxyl radicals. EC50 values for free radical elimination were 7.69 and 17.8 mg/mL, for ABTS+ and hydroxyls, respectively. The polysaccharides showed potential for α-amylase inhibition with an EC50 of 1.66 mg/mL. The results suggest that ß(1,3) ß(1,6) glucogalactan from Rhizopus microsporus var. oligosporus can be used in biotechnological applications.


Assuntos
Antioxidantes , Rhizopus , alfa-Amilases , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , alfa-Amilases/antagonistas & inibidores , Espectroscopia de Infravermelho com Transformada de Fourier , Galactanos/isolamento & purificação , Galactanos/farmacologia , Galactanos/química , Espectroscopia de Ressonância Magnética , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/isolamento & purificação , Concentração de Íons de Hidrogênio
13.
Food Chem ; 456: 140056, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38878546

RESUMO

In this study, carrageenan (CG), xanthan gum (XG) and locust bean gum (LBG), which can be used in infant formulas in China national standards, were selected to prepare LF-polysaccharide complexes to improve the stability of lactoferrin. The results showed that LF interacted more strongly with polysaccharides and did not affect the LF structure to a large extent when the pH and protein/polysaccharide mass ratio were 7 and 10:1 for LF-CG, 8 and 5:1 for LF-XG, 7 and 15:1 for LF-LBG. The zeta potential and fluorescence intensity of the LF-polysaccharide complexes displayed a decreasing trend with the increase in pH. When pH < 6, LF-CG and LF-XG exhibited precipitation and increased UV absorbance. Complexation between LF and CG/XG mainly attributed to electrostatic interactions, while LF and LBG form complexes based on hydrogen bonding or hydrophobic interactions. This study could provide a reference for the practical application of LF in infant formula.


Assuntos
Fórmulas Infantis , Lactoferrina , Polissacarídeos , Lactoferrina/química , Concentração de Íons de Hidrogênio , Polissacarídeos/química , Fórmulas Infantis/química , Galactanos/química , Polissacarídeos Bacterianos/química , Gomas Vegetais/química , Mananas/química , Humanos , Carragenina/química
14.
Food Chem ; 456: 140090, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38878542

RESUMO

Few studies have been conducted on the relationship between the crosslinking ability of dialdehyde polysaccharides (DPs) with different structures and the structure and properties of hydrogels. Herein, the effects of dialdehyde sodium alginate (DSA), dialdehyde guar gum (DGG), and dialdehyde dextran (DDE) as crosslinking agents for gelatin (GE)-based hydrogels were comparatively studied. First, the structure and aldehyde content of DPs were evaluated. Subsequently, the structure, crosslinking degree, and physicochemical properties of GE/DP hydrogels were characterized. Compared with pure GE hydrogels, GE/DP hydrogels had higher thermal stability and mechanical properties. Moreover, the aldehyde content of DPs was ordered as follows: DSA < DGG < DDE. The higher crosslinking degree of the hydrogels formed by DPs with a higher aldehyde content resulted in smaller hydrogel pores, higher mechanical strength, and a lower equilibrium swelling rate. These observations provide a theoretical basis for selecting crosslinking candidates for hydrogel-specific applications.


Assuntos
Reagentes de Ligações Cruzadas , Gelatina , Hidrogéis , Polissacarídeos , Bases de Schiff , Gelatina/química , Hidrogéis/química , Polissacarídeos/química , Reagentes de Ligações Cruzadas/química , Bases de Schiff/química , Galactanos/química , Gomas Vegetais/química , Mananas/química
15.
Bioresour Technol ; 406: 130979, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38879054

RESUMO

Addressing the drawbacks of traditional flocculants on microalgae biomass harvesting is crucial for large-scale industrial applications of microalgae production. In this study, cationic bioflocculant was successfully prepared by introducing cationic groups into the side chain of guar gum, achieving in-situ algae flocculation efficiency of 83.5 % with the dosage of 18.0 mg/L under pH = 10.0. Through a harmonious integration of predictive modelling and practical experimentation, a superior cell flocculation capacity of 23.5 g/g was achieved. In addition, the environmental safety and biocompatibility of cationic guar gum was assessed, using the typical suspension quantitative bacteriostatic method and the fluorescent double-staining technique. The results showed that the inhibition efficiency of Staphylococcus aureus in the system containing 60.0 mg/L cationic guar gum was only 12.0 % and there was no inhibition against Escherichia coli colonies. These findings provide a safe and green flocculant for efficient microalgae harvesting and spent medium treatment.


Assuntos
Cátions , Floculação , Galactanos , Mananas , Microalgas , Gomas Vegetais , Galactanos/farmacologia , Galactanos/química , Gomas Vegetais/química , Gomas Vegetais/farmacologia , Floculação/efeitos dos fármacos , Mananas/farmacologia , Mananas/química , Microalgas/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio
16.
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
17.
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
18.
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
19.
J Med Invest ; 71(1.2): 121-128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38735707

RESUMO

OBJECTIVES: Partially hydrolyzed guar gum (PHGG) is a soluble dietary fiber;in addition to improving bowel movements, it maintains intestinal health by producing short-chain fatty acids. However, majority of clinical studies on PHGG have been concluded within a month and excluded usual drug therapy. Hence, this study aimed to determine the effects of long-term consumption of PHGG, in combination with drug therapy, on gut bacteria ratios, laboratory values for inflammatory response, and fecal characteristics. METHODS AND RESULTS: The study was performed in patients with irritable bowel syndrome (IBS), Crohn's disease (CD), and ulcerative colitis (UC), by the administration of PHGG for six months while they continued their usual treatment. PHGG treatment caused significant changes in patients with IBS, including an increase in the abundance of short-chain fatty acid-producing bacteria, a significant decrease in Bacteroides abundance, and normalization of the Bristol scale of stool. In patients with UC, non-significant normalization of soft stools and decrease in fecal calprotectin were observed. Adverse events were not observed in any of the groups. CONCLUSION: Thus, it would be beneficial to include PHGG in the usual drug therapies of patients with IBS. J. Med. Invest. 71 : 121-128, February, 2024.


Assuntos
Fibras na Dieta , Galactanos , Microbioma Gastrointestinal , Síndrome do Intestino Irritável , Mananas , Gomas Vegetais , Humanos , Microbioma Gastrointestinal/efeitos dos fármacos , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/microbiologia , Masculino , Feminino , Fibras na Dieta/administração & dosagem , Adulto , Pessoa de Meia-Idade , Mananas/administração & dosagem , Gomas Vegetais/administração & dosagem , Galactanos/administração & dosagem , Doenças Inflamatórias Intestinais/tratamento farmacológico , Fezes/microbiologia , Fezes/química , Ácidos Graxos Voláteis/análise , Ácidos Graxos Voláteis/metabolismo
20.
Langmuir ; 40(19): 10305-10312, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38696716

RESUMO

The limited elasticity and inadequate bonding of hydrogels made from guar gum (GG) significantly hinder their widespread implementation in personalized wearable flexible electronics. In this study, we devise GG-based self-adhesive hydrogels by creating an interpenetrating network of GG cross-linked with acrylic, 4-vinylphenylboronic acid, and Ca2+. With the leverage of the dynamic interactions (hydrogen bonds, borate ester bonds, and coordination bonds) between -OH in GG and monomers, the hydrogel exhibits a high stretchability of 700%, superior mechanical stress of 110 kPa, and robust adherence to several substrates. The adhesion strength of 54 kPa on porcine skin is obtained. Furthermore, the self-adhesive hydrogel possesses stable conductivity, an elevated gauge factor (GF), and commendable durability. It can be affixed to the human body as a strain sensor to obtain precise monitoring of human movement behavior. Our research offers possibilities for the development of GG-based hydrogels and applications in wearable electronics and medical monitoring.


Assuntos
Condutividade Elétrica , Galactanos , Hidrogéis , Mananas , Gomas Vegetais , Hidrogéis/química , Mananas/química , Gomas Vegetais/química , Galactanos/química , Animais , Dispositivos Eletrônicos Vestíveis , Humanos , Suínos , Adesivos/química
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