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1.
Molecules ; 29(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38611855

RESUMO

Quinoa, known as the "golden grain" for its high nutritional value, has polysaccharides as one of its sources of important nutrients. However, the biological functions of quinoa polysaccharides remain understudied. In this study, two crude polysaccharide extracts of quinoa (Q-40 and Q-60) were obtained through sequential precipitation with 40% and 60% ethanol, with purities of 58.29% (HPLC) and 62.15% (HPLC) and a protein content of 8.27% and 9.60%, respectively. Monosaccharide analysis revealed that Q-40 contained glucose (Glc), galacturonic acid (GalA), and arabinose (Ara) in a molar ratio of 0.967:0.027:0.006. Q-60 was composed of xylose (xyl), arabinose (Ara), galactose, and galacturonic acid (GalA) with a molar ratio of 0.889:0.036:0.034:0.020. The average molecular weight of Q-40 ranged from 47,484 to 626,488 Da, while Q-60 showed a range of 10,025 to 47,990 Da. Rheological experiments showed that Q-40 exhibited higher viscosity, while Q-60 demonstrated more elastic properties. Remarkably, Q-60 showed potent antioxidant abilities, with scavenging rates of 98.49% for DPPH and 57.5% for ABTS. Antibacterial experiments using the microdilution method revealed that Q-40 inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), while Q-60 specifically inhibited MRSA. At lower concentrations, both polysaccharides inhibited MDA (MD Anderson Cancer Center) cell proliferation, but at higher concentrations, they promoted proliferation. Similar proliferation-promoting effects were observed in HepG2 cells. The research provides important information in the application of quinoa in the food and functional food industries.


Assuntos
Chenopodium quinoa , Ácidos Hexurônicos , Staphylococcus aureus Resistente à Meticilina , Arabinose , Escherichia coli , Grão Comestível
2.
J Gen Virol ; 105(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38656455

RESUMO

Porcine epidemic diarrhea (PED) is a serious disease in piglets that leads to high mortality. An effective measure that provides higher IgA levels in the intestine and milk is required to decrease losses. Porcine epidemic diarrhea virus (PEDV) was dissolved in calcium alginate (Alg) and combined with chitosan (CS) via electrostatic interactions between cationic chitosan and anionic alginate to create a porous gel (Alg-CS+PEDV). The gel was used to immunize mice orally or in combination with subcutaneous injections of inactivated PEDV vaccine. At 12 and 24 days after immunization, levels of IgA and IgG in Alg-CS+PEDV were higher than with normal PEDV oral administration. At 24 days after immunization, the concentration of IFN-γ in Alg-CS+PEDV was higher than with normal PEDV oral administration. Furthermore, oral administration combining subcutaneous immunization induced higher levels of IgG and IgA than oral administration alone. Our study provides a new method for the preparation and administration of oral vaccines to achieve enhanced mucosal immunity against PEDV.


Assuntos
Alginatos , Anticorpos Antivirais , Quitosana , Imunidade nas Mucosas , Imunoglobulina A , Imunoglobulina G , Vírus da Diarreia Epidêmica Suína , Vacinas Virais , Animais , Administração Oral , Vírus da Diarreia Epidêmica Suína/imunologia , Alginatos/administração & dosagem , Quitosana/administração & dosagem , Camundongos , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Anticorpos Antivirais/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Suínos , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Feminino , Géis/administração & dosagem , Camundongos Endogâmicos BALB C , Interferon gama/imunologia , Ácido Glucurônico/administração & dosagem , Ácidos Hexurônicos/administração & dosagem
3.
Sci Rep ; 14(1): 9182, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649422

RESUMO

In order to obtain high yield pomelo peel pectin with better physicochemical properties, four pectin extraction methods, including hot acid extraction (HAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction, and enzymatic assisted extraction (EAE) were compared. MAE led to the highest pectin yield (20.43%), and the lowest pectin recovery was found for EAE (11.94%). The physicochemical properties of pomelo peel pectin obtained by different methods were also significantly different. Pectin samples obtained by MAE had the highest methoxyl content (8.35%), galacturonic acid content (71.36%), and showed a higher apparent viscosity, thermal and emulsion stability. The pectin extracted by EAE showed the highest total phenolic content (12.86%) and lowest particle size (843.69 nm), showing higher DPPH and ABTS scavenging activities than other extract methods. The pectin extracted by HAE had the highest particle size (966.12 nm) and degree of esterification (55.67%). However, Fourier-transform infrared spectroscopy showed that no significant difference occurred among the different methods in the chemical structure of the extracted pectin. This study provides a theoretical basis for the industrial production of pomelo peel pectin.


Assuntos
Citrus , Ácidos Hexurônicos , Pectinas , Pectinas/química , Pectinas/isolamento & purificação , Citrus/química , Viscosidade , Tamanho da Partícula , Micro-Ondas , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Fracionamento Químico/métodos , Fenômenos Químicos , Frutas/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fenóis/análise , Fenóis/química , Fenóis/isolamento & purificação , Esterificação
4.
J Mater Sci Mater Med ; 35(1): 19, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526655

RESUMO

The efficacy of stem-cell therapy depends on the ability of the transplanted cells to escape early immunological reactions and to be retained at the site of transplantation. The use of tissue engineering scaffolds or injectable biomaterials as carriers has been proposed, but they still present limitations linked to a reliable manufacturing process, surgical practice and clinical outcomes. Alginate microbeads are potential candidates for the encapsulation of mesenchymal stromal cells with the aim of providing a delivery carrier suitable for minimally-invasive and scaffold-free transplantation, tissue-adhesive properties and protection from the immune response. However, the formation of stable microbeads relies on the cross-linking of alginate with divalent calcium ions at concentrations that are toxic for the cells, making control over the beads' size and a single-cell encapsulation unreliable. The present work demonstrates the efficiency of an innovative, high throughput, and reproducible microfluidic system to produce single-cell, calcium-free alginate coatings of human mesenchymal stromal cells. Among the various conditions tested, visible light and confocal microscopy following staining of the cell nuclei by DAPI showed that the microfluidic system yielded an optimal single-cell encapsulation of 2000 cells/min in 2% w/v alginate microcapsules of reproducible morphology and an average size of 28.2 ± 3.7 µm. The adhesive properties of the alginate microcapsules, the viability of the encapsulated cells and their ability to escape the alginate microcapsule were demonstrated by the relatively rapid adherence of the beads onto tissue culture plastic and the cells' ability to gradually disrupt the microcapsule shell after 24 h and proliferate. To mimic the early inflammatory response upon transplantation, the encapsulated cells were exposed to proliferating macrophages at different cell seeding densities for up to 2 days and the protection effect of the microcapsule on the cells assessed by time-lapse microscopy showing a shielding effect for up to 48 h. This work underscores the potential of microfluidic systems to precisely encapsulate cells by good manufacturing practice standards while favouring cell retention on substrates, viability and proliferation upon transplantation.


Assuntos
Células-Tronco Mesenquimais , Microfluídica , Humanos , Encapsulamento de Células , Cápsulas , Medula Óssea , Alginatos/química , Ácidos Hexurônicos/química , Sobrevivência Celular , Ácido Glucurônico/química
5.
Plant Physiol Biochem ; 208: 108495, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452451

RESUMO

Solanum lycopersicum (Tomato) leaves and stems are considered waste. Valorization of this waste can be achieved by for example the extraction of proteins. This prospect is promising but currently not feasible, since protein extraction yields from tomato leaves are low, amongst other due to the (physical) barrier formed by the plant cell walls. However, the molecular aspects of the relationship between cell wall properties and protein extractability from tomato leaves are currently not clear and thus objective of this study. To fill this knowledge gap the biochemical composition of plant cell walls was measured and related to protein extraction yields at different plant ages, leaf positions, and across different tomato accessions, including two Solanum lycopersicum cultivars and the wildtype species S. pimpinellifolium and S. pennellii. For all genotypes, protein extraction yields from tomato leaves were the highest in young tissues, with a decreasing trend towards older plant material. This decrease of protein extraction yield was accompanied by a significant increase of arabinose and galacturonic acid content and a decrease of galactose content in the cell walls of old-vs-young tissues. This resulted in strong negative correlations between protein extraction yield and the content of arabinose and galacturonic acid in the cell wall, and a positive correlation between the content of galactose and protein extraction yield. Overall, these results point to the importance of the pectin network on protein extractability, making pectin a potential breeding target for enhancing protein extractability from tomato leaves.


Assuntos
Ácidos Hexurônicos , Solanum lycopersicum , Solanum lycopersicum/genética , Arabinose , Galactose , Melhoramento Vegetal , Parede Celular/metabolismo , Folhas de Planta/metabolismo , Pectinas/metabolismo
6.
Int J Biol Macromol ; 263(Pt 2): 130452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417755

RESUMO

As a traditional Chinese medicinal and edible homologous plant, Onosma glomeratum Y. L. Liu has been used for treating lung diseases in Tibet. In this study, a pectin polysaccharide, OGY-LLPA, with a molecular weight of 62,184 Da, was isolated and characterized by GC-MS and NMR analysis. It mainly consists of galacturonic acid (GalA), galactose (Gal), rhamnose (Rha), and arabinose (Ara), with a linear main chain of galacturonic acid (homogalacturonan, HG) inserted by part of rhamnose galacturonic acid (rhamnogalacturonan, RG), attaching with arabinogalactan (AG) branches at RG-I. Both in the LPS-induced A549 cell model and LPS-induced pneumonia mouse model, OGY-LLPA demonstrated strong anti-inflammatory effects, even comparable to DEX, indicating its potential as an anti-pneumonia candidate agent. Moreover, low-dose OGY-LLPA alleviated LPS-induced pulmonary inflammation by inhibiting the NF-κB signaling pathway. Overall, these findings could not only contribute to the utilization of Onosma glomeratum Y. L. Liu., but also provides a theoretical basis for the treatment of inflammation-related diseases.


Assuntos
Ácidos Hexurônicos , NF-kappa B , Pneumonia , Camundongos , Animais , Lipopolissacarídeos , Ramnose , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos/análise , Transdução de Sinais , Pneumonia/induzido quimicamente , Pneumonia/tratamento farmacológico
7.
Int J Biol Macromol ; 262(Pt 1): 130006, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331067

RESUMO

The processing characteristics of yogurt are closely related to the composition and arrangement of exopolysaccharides (EPS) in lactic acid bacteria (LAB). To fully understand and develop the functional properties of EPS and to study the effect of EPS molecular weight on yogurt and its mechanism, the physicochemical properties of high molecular weight EPS-LH43, medium molecular weight EPS-LH13, and low molecular weight EPS-LH23, as well as the gel properties and protein conformation of yogurt, were determined and analyzed in this experiment. The results indicate that EPS-LH43 and EPS-LH13 are both composed of mannose, rhamnose, galacturonic acid, glucose, and galactose. EPS-LH23 is composed of mannose, galacturonic acid, glucose, and galactose. Their Number-average Molecular Weight is 5.21 × 106 Da, 2.39 × 106 Da and 3.76 × 105 Da, respectively. In addition, all three types of EPS have good thermal stability and can improve the stability of casein. In addition, the analysis of the texture, particle size, potential, water holding capacity, rheology, low field nuclear magnetic resonance, microstructure, and flavor characteristics of yogurt confirmed the relationship between the molecular weight of LAB EPS and the gel properties of yogurt. Fluorescence spectrophotometer and circular dichroism analysis indicate that the different molecular weights of LAB EPS have different effects on protein structure, which is an intrinsic factor leading to significant differences in the gel properties of the three types of fermented milk. These findings provide new references for enhancing the understanding of the structure-activity relationship of EPS and indicate that EPS-LH43 can be used to improve the gel properties of dairy products.


Assuntos
Ácidos Hexurônicos , Lactobacillus helveticus , Iogurte , Iogurte/microbiologia , Polissacarídeos Bacterianos/química , Peso Molecular , Galactose/análise , Manose , Glucose/análise , Fermentação
8.
Int J Biol Macromol ; 254(Pt 1): 127658, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37898241

RESUMO

Pectin yield of 22.22 ± 0.98 % (dry basis) was achieved from prematurely dropped Golden Delicious apples, having a light orange hue (hue value: 78.08 ± 0.04) and an overall color difference (ΔE) of 9.92 ± 0.01 compared to commercial pectin (CP). Extracted AP exhibited a lower equivalent weight (725.24 ± 29.73) and higher methoxy content (8.36 ± 0.28 %) in contrast to CP. However, a similar degree of esterification of 71.57 ± 0.79 and 70.55 ± 0.59 %, was observed in AP and CP respectively. Apple pectin demonstrated slight lower galacturonic acid (GalA) content of 68.10 ± 3.94 % in comparison to 72.31 ± 4.62 % of CP, which was further corroborated by reduced intensity in FTIR fingerprint region (912-1025 cm-1). Morphology revealed a sheet-like cloudy appearance indicating a significant presence of associated sugars whereas X-ray diffraction highlighted the highly amorphous nature of AP. AP and CP solutions (3-9 %) displayed a shear-thinning flow and viscoelastic behavior where the loss (G') moduli dominated over the storage moduli (G"). Owing to high degree of esterification, galacturonic acid content (>65 %) that aligns with commercial standards and viscoelastic behavior, the extracted AP holds promise for potential utilization in commercial applications. This study underscores the potential for sustainable utilization of prematurely dropped apples through pectin extraction, contributing to valorization of the wasted bioresource.


Assuntos
Malus , Pectinas , Pectinas/química , Malus/química , Ácidos Hexurônicos
9.
J Sci Food Agric ; 104(4): 2458-2466, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37975168

RESUMO

BACKGROUND: Calcium alginate gels are widely used to encapsulate active compounds. Some characteristic parameters of these gels are necessary to describe the release of active compounds through mechanistic mathematical models. In this work, transport and kinetics properties of calcium alginate gels were determined through simple experimental techniques. RESULTS: The weight-average molecular weight ( M ¯ w = 192 × 103 Da) and the fraction of residues of α-l-guluronic acid ( F G = 0.356) of sodium alginate were determined by capillary viscometry and 1 H-nuclear magnetic resonance at 25 °C, respectively. Considering the half egg-box model, both values were used to estimate the molecular weight of calcium alginate as M g = 2.02 × 105 Da. An effective diffusion coefficient of water ( D eff , w = 2.256 × 10-9 m2 s-1 ) in calcium alginate was determined using a diffusion cell at 37 °C. Finally, a kinetics constant of depolymerization ( k m = 9.72 × 10-9 m3 mol-1 s-1 ) of calcium alginate was obtained considering dissolution of calcium to a medium under intestinal conditions. CONCLUSION: The experimental techniques used are simple and easily reproducible. The obtained values may be useful in the design, production, and optimization of the alginate-based delivery systems that require specific release kinetics of the encapsulated active compounds. © 2023 Society of Chemical Industry.


Assuntos
Alginatos , Imageamento por Ressonância Magnética , Alginatos/química , Géis/química , Espectroscopia de Ressonância Magnética , Modelos Teóricos , Cálcio/química , Ácidos Hexurônicos/química , Ácido Glucurônico/química
10.
Int J Biol Macromol ; 254(Pt 3): 127869, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939773

RESUMO

There is an increasing demand for obtaining pectin from new sources. Red radish (Raphanus sativus L.) pomace pectin extracted by alkali was low-methoxyl pectin with esterification degree of 10.17 %, galacturonic acid content of 69.71 % (wt), and average molar weight of 78.59 kDa. The pectin primarily consisted of rhamnogalacturonan I and homogalacturonan domains. The predominant monosaccharides of the pectin were galacturonic acid (46.32 mol%), arabinose (16.03 mol%), galactose (10.46 mol%), and rhamnose (10.28 mol%), respectively. The red radish pomace pectin solution exhibited a shear-thinning behavior. NaCl could induce gelation of red radish pomace pectin, and the gel properties of red radish pomace pectin were considerably affected by the NaCl concentration. As the NaCl concentration (0.25-0.50 mol/L) increased, the rate of gelation accelerated, and the time to gelation point appeared earlier. There was an optimal NaCl concentration (0.50 mol/L) for the pectin to form a gel with the greatest solid-like properties, gel hardness (33.84 g) and water-holding capacity (62.41 %). Gelation force analysis indicated gel formation mainly caused by electrostatic shielding effect of Na+ and hydrogen bonding. This research could facilitate the applications of the red radish pomace pectin in the realm of edible hydrocolloids.


Assuntos
Raphanus , Cloreto de Sódio , Pectinas/análise , Ácidos Hexurônicos/análise
11.
Langmuir ; 40(3): 1950-1960, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-37991242

RESUMO

Core-shell hydrogel microcapsules have sparked great interest due to their unique characteristics and prospective applications in the medical, pharmaceutical, and cosmetic fields. However, complex synthetic procedures and expensive costs have limited their practical application. Herein, we designed and prepared several multichannel and multijunctional droplet microfluidic devices based on soft lithography for the effective synthesis of core-shell hydrogel microcapsules for different purposes. Additionally, two different cross-linking processes (ultraviolet (UV) exposure and interfacial polymerization) were used to synthesize different types of core-shell structured hydrogel microcapsules. Hydrogel microcapsules with gelatin methacryloyl (GelMA) as the core and polyacrylamide (PAM) as the thin shell were synthesized using UV cross-linking. Using an interfacial polymerization process, another core-shell structured microcapsule with GelMA as the core and Ca2+ cross-linked alginate with polyethylenimine (PEI) as the shell was constructed, and the core diameter and total droplet diameter were flexibly controlled by carving. Noteworthy, these hydrogel microcapsules exhibit stimuli-responsiveness and controlled release ability. Overall, a novel technique was developed to successfully synthesize various hydrogel microcapsules with core-shell microstructures. The hydrogel microcapsules possess a multilayered structure that facilitates the coassembly of cells and drugs, as well as the layered assembly of multiple drugs, to develop synergistic therapeutic regimens. These adaptable and controllable hydrogel microdroplets shall held great promise for multicell or multidrug administration as well as for high-throughput drug screening.


Assuntos
Alginatos , Hidrogéis , Hidrogéis/química , Cápsulas/química , Alginatos/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química
12.
Int J Biol Macromol ; 258(Pt 2): 129062, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159691

RESUMO

A natural polysacharide, gum odina was collected from Odina wodier tree and purified. Purified gum odina was used with sodium alginate for immobilization of α-amylase. Calcium alginate-gum odina (CA-GO) beads were prepared by ionotropic gelation method to find the improvement of immobilization efficiency and reusability of α-amylase over calcium alginate (CA) beads. XRD, SEM, FTIR, beads diameter, enzyme leaching from beads, moisture content, total soluble matter and swelling study have been carried out to understand the physical morphology and mechanism of immobilization of enzyme in beads matrix. It has been observed that if the polymer ratio changes (keeping enzyme conc. & calcium Chloride conc. constant) then the size and shape of the beads will vary and at a particular range of polymer ratio, the optimal beads forms. At a certain conc.(4%w/v of SA and 1%w/v GO), the immobilization efficiency of CA-GO and CA beads were 92.71 ± 0.85 % (w/w) and 89.19 ± 0.35 %(w/w) respectively. After 8th time use, the CA-GO beads remain (~4 fold) more active than that of CA beads. The FTIR confirms that GO does not interfere with α-Amylase and alginate. Here, it can be concluded that CA-GO beads show better efficiency in respect to immobilization, reusability than CA beads only.


Assuntos
Alginatos , alfa-Amilases , Enzimas Imobilizadas , Cloreto de Cálcio , Polímeros , Ácidos Hexurônicos , Ácido Glucurônico
13.
J Environ Manage ; 351: 119872, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157579

RESUMO

Controlled release of active ingredients are important for drug delivery and more recently environmental applications including modulated dosing of chemical and biological controls. This study demonstrates the importance of investigating various material science factors that can influence the diffusion rates of alginate beads to improve and tune their performance for marine environmental applications. This investigation aimed to design a rational workflow to aid in leveraging alginate bead use as a carrier matrix for releasing a specific active agent into water. Experiments were conducted to focus on the narrow a large list of relevant material formulation parameters, which included chitosan molecular weight, chitosan concentration, calcium concentration, drop height, and bead size. Once the most relevant material preparation methods were screened, a more robust statistic Design of Experiments approach was performed and results determined the important (and unimportant) factors for increasing dye release kinetics in marine water. The process was further streamlined by narrowing the critical experimental factors to a three-level based on the prior analysis: chitosan MW, chitosan concentration, and bead size. Analysis of the collected data indicated that while chitosan MW had a negligible impact (Fstatistic = 0.22), bead size (Fstatistic = 60.33) significantly influenced the diffusion rates based on surface area. However, chitosan MW had minor effects where lower chitosan MW enabled higher product release rates. This case investigation was a novel application of the design of experiment approach towards environmental applications to understand differences in release rates to marine waters for the first time and the workflow provided also serve as the basis for researchers to optimize other environmental applications requiring optimization when it is unknown how a large number of formulation variables will impact performance in different environmental scenarios.


Assuntos
Quitosana , Quitosana/química , Alginatos/química , Cálcio , Água , Ácidos Hexurônicos/química , Ácido Glucurônico/química
14.
Int J Mol Sci ; 24(22)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38003391

RESUMO

This study considers the potential of elemental analysis of polysaccharide ionotropic gels in elucidating the junction zones for different divalent cations. The developed algorithm ensures the correct separation of contributions from physically adsorbed and structure-forming ionic compounds, with the obtained results scaled to alginate C12 block. Possible versions of chain association into dimers and their subsequent integration into flat junction zones were analyzed within the framework of the "egg-box" model. The application of combinatorial analysis made it possible to derive theoretical relations to find the probability of various types of egg-box cell occurrences for alginate chains with arbitrary monomeric units ratio µ = M/G, which makes it possible to compare experimental data for alginates of different origins. Based on literature data and obtained chemical formulas, the possible correspondence of concrete biopolymer cells to those most preferable for filling by alkaline earth cations was established. The identified features of elemental composition suggest the formation of composite hydrated complexes with the participation of transition metal cations. The possibility of quantitatively assessing ordered secondary structures formed due to the physical sorption of ions and molecules from environment, correlating with the sorption capabilities of Me2+ alginate, was established.


Assuntos
Alginatos , Ácidos Hexurônicos/química , Alginatos/química , Ácido Glucurônico/química , Cátions/química , Cátions Bivalentes/química , Géis/química
15.
Pak J Pharm Sci ; 36(5(Special)): 1627-1635, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38008961

RESUMO

The study aimed to prepare and characterize biodegradable sustained-release beads of letrozole (LTZ) for treating cancerous disease. The ionotropic gelation method was used for the preparation and calcium chloride (CaCl2) was used as a gelating agent, while chitosan (CTS) and sodium alginate (NaAlg) as biodegradable polymeric matrices in the blend hydrogel beads. The beads were characterized for their size, surface morphology, drug entrapment efficiency, drug-polymer interaction and crystallinity using different analytic techniques, including optical microscopy, Scanning Electron Microscopy (SEM), UV-spectroscopy, Fourier-transform Infrared Spectroscopy (FTIR), Thermo gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and X-ray Diffraction Analysis (XRD) respectively. In vitro swelling studies were also applied to observe the response of these polymeric networks against different pH (at 1.2, 6.8 and 7.4 pH). The results from TGA and DSC exhibited that the components in the formulation possess better thermal stability. The XRD of polymeric networks displays a minor crystalline and significant amorphous nature. The SEM micrographs revealed that polymeric networks have uneven surfaces and grooves. Better swelling and in vitro outcomes were achieved at a high pH (6.8,7.4), which endorsed the pH-responsive characteristics of the prepared beads. Hence, beads based on chitosan and sodium alginate were successfully synthesized and can be used for the controlled release of letrozole.


Assuntos
Quitosana , Preparações de Ação Retardada , Letrozol , Quitosana/química , Tamanho da Partícula , Polímeros , Alginatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Hexurônicos/química , Microscopia Eletrônica de Varredura , Ácido Glucurônico/química
16.
Int J Biol Macromol ; 249: 126117, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37541481

RESUMO

Kidney tea saponin (KTS) exhibits considerable efficacy in lowering glucose levels; however, it does not have widespread applications owing to its low intestinal utilization. Therefore, in the present study, we prepared sodium alginate (SA)/sodium hyaluronate (HA)/hydrolyzed silk (SF) gel beads for the effective encapsulation and targeted intestinal release of KTS. The gel beads exhibited an encapsulation rate of 90.67 % ± 0.27 % and a loading capacity of 3.11 ± 0.21 mg/mL; furthermore, the release rate of KTS was 95.46 % ± 0.02 % after 8 h of simulated digestion. Fourier transform infrared spectroscopy revealed that the hydroxyl in SA/HA/SF-KTS was shifted toward the strong peak; this was related to KTS encapsulation. Furthermore, scanning electron microscopy revealed that the gel bead space network facilitates KTS encapsulation. In addition, the ability of KTS and the gel beads to inhibit α-amylase (IC50 = 0.93 and 1.37 mg/mL, respectively) and α-glucosidase enzymes (IC50 = 1.17 and 0.93 mg/mL, respectively) was investigated. In vitro colonic fermentation experiments revealed that KTS increased the abundance of Firmicutes/Bacteroidetes and butyric acid-producing bacteria. The study showed that the developed gel-loading system plays a vital role in delivering bioactive substances, achieving slow release, and increasing the abundance and diversity of intestinal flora.


Assuntos
Alginatos , Microbioma Gastrointestinal , Humanos , Alginatos/química , Preparações de Ação Retardada/farmacologia , Ácido Hialurônico , Seda , Chá , Rim , Ácidos Hexurônicos/química , Ácido Glucurônico/química
17.
Molecules ; 28(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446863

RESUMO

The present article describes a one-pot and cascade mode process using biocompatible/biodegradable reagents, for simply obtaining surfactant compositions comprising mixtures of d-mannuronic acid and l-guluronic acid directly from oligoalginates or semi-refined alginates (mixtures of alginate, cellulose, hemicellulose, laminaran, and fucan). Simple treatments of partial purification of the reaction crudes (elimination of the salts and/or the residual fatty alcohols) or isolation of the surfactant compositions result in sugar-based compounds having performance levels appropriate to applications in detergency. In addition, the challenging extension of this cascading one-pot synthesis technology to crude milled brown seaweeds was successfully carried out to provide promising surface-active compositions made up of alkyl uronate and alkyl glycoside monosaccharides.


Assuntos
Alga Marinha , Ácidos Urônicos , Alginatos , Tensoativos , Ácidos Hexurônicos , Glicosaminoglicanos
18.
Chembiochem ; 24(19): e202300456, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37439603

RESUMO

Horse Liver Alcohol Dehydrogenase (HLADH) has been immobilized on calcium-alginate beads and used for both oxidation and reduction reactions. To avoid swelling of the beads and their subsequent breakage, calcium ions were added to both reaction and storage solutions, allowing the beads to maintain the initial structural features. The techniques used for this purpose revealed that 2 mM Ca2+ is the optimal concentration, which does not significantly change the weight of the beads, the amount of water in them, and their external and internal structure. The optimized experimental procedure has been used to verify the properties of the enzyme in terms of reusability, storage, and thermal stability. The addition of calcium ions allows the enzyme to retain more than 80 % of its initial activity for fourteen cycles and approximately 50 % at the twentieth cycle. Moreover, when the biocatalyst has been stored in a buffer solution containing 2 mM Ca2+ , the retention of enzyme activity after 30 days was 100 %, compared to that measured before incubation. The encapsulated enzyme exhibits greater thermal stability than free HLADH up to at least 60 °C, preventing dimer dissociation into the two subunits.


Assuntos
Álcool Desidrogenase , Enzimas Imobilizadas , Cavalos , Animais , Enzimas Imobilizadas/metabolismo , Cálcio/química , Alginatos/química , Fígado , Íons , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Estabilidade Enzimática
19.
Int J Pharm ; 643: 123260, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37481097

RESUMO

The Ca2+ ion-driven emulsification-ionotropic gelation method produced chitosan-alginate microspheres (CAMSs) with a narrow particle size distribution (PSD). Particle size distribution and zeta potential studies, as well as spectral electron microscopy, were used to assess the microspheres' physicochemical properties and morphology. The tyrosols (hydroxytyrosol (HT), tyrosol (TY), and oleuropein (OE) were loaded into these microspheres using a polyphenol extract (PPE) from Koroneki olive mill waste (KOMW). The microencapsulation efficiency and loading capacity of microspheres for PPE were 98.8% and 3.9%, respectively. Three simulated fluids, including gastric (pH = 1.2), intestinal (pH = 6.8), and colonic (pH = 7.4), were used to examine how the pH of the releasing medium affected the ability of CAMSs to release bioactive phenols. At a severely acidic pH (1.2, SGF), PPE release is nearly halted, while at pH 6.8 (SCF), release is at its maximum. Additionally, the PPE-CAMPs have ameliorated the endogenous antioxidant content SOD, GST, GPx with significant values from 0.05 to 0.01 in the treated LPS/human skin fibroblast cells. The anti-inflammatory response was appeared through their attenuations activity for the released cytokines TNF-α, IL6, IL1ß, and IL 12 with levels significantly from 0.01 to 0.001. Microencapsulation of PPE by CAMPs significantly improved its antioxidant and anti-inflammatory capabilities.


Assuntos
Quitosana , Olea , Humanos , Quitosana/química , Lipopolissacarídeos , Alginatos/química , Inflamação , Fibroblastos , Microesferas , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Ácidos Hexurônicos , Ácido Glucurônico
20.
Int J Biol Macromol ; 244: 125481, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37343612

RESUMO

In the past decades, the microencapsulation of mammalian cells into microparticles has been extensively studied for various in vitro and in vivo applications. The aim of this study was to demonstrate the viability of bacterial polyglucuronic acid (PGU), an exopolysaccharide derived from bacteria and composed of glucuronic acid units, as an effective material for cell microencapsulation. Using the method of dropping an aqueous solution of PGU-containing cells into a Ca2+-loaded solution, we produced spherical PGU microbeads with >93 % viability of the encapsulated human hepatoma HepG2 cells. Hollow-core microcapsules were formed via polyelectrolyte complex layer formation of PGU and poly-l-lysine, after which Ca2+, a cross-linker of PGU, was chelated, and this was accomplished by sequential immersion of microbeads in aqueous solutions of poly-l-lysine and sodium citrate. The encapsulated HepG2 cells proliferated and formed cell aggregates within the microparticles over a 14-day culture, with significantly larger aggregates forming within the microcapsules. Our results provide evidence for the viability of PGU for cell microencapsulation for the first time, thereby contributing to advancements in tissue engineering.


Assuntos
Polilisina , Engenharia Tecidual , Animais , Humanos , Cápsulas , Microesferas , Alginatos , Ácido Glucurônico , Ácidos Hexurônicos , Mamíferos
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