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1.
Mar Drugs ; 20(2)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35200618

RESUMO

In many African countries, the Bayoud is a common disease spread involving the fungus Fusarium oxusporum f. sp. albedinis (Foa). The induction of plant natural defenses through the use of seaweed polysaccharides to help plants against pathogens is currently a biological and ecological approach that is gaining more and more importance. In the present study, we used alginate, a natural polysaccharide extracted from a brown algae Bifurcaria bifurcata, to activate date palm defenses, which involve phenylalanine ammonia-lyase (PAL), a key enzyme of phenylpropanoid metabolism. The results obtained showed that at low concentration (1 g·L-1), alginate stimulated PAL activity in date palm roots 5 times more compared to the negative control (water-treated) after 24 h following treatment and 2.5 times more compared to the laminarin used as a positive stimulator of plant natural defenses (positive control of induction). Using qRT-PCR, the expression of a selection of genes involved in three different levels of defense mechanisms known to be involved in response to biotic stresses were investigated. The results showed that, generally, the PAL gene tested and the genes encoding enzymes involved in early oxidative events (SOD and LOX) were overexpressed in the alginate-treated plants compared to their levels in the positive and negative controls. POD and PR protein genes selected encoding ß-(1,3)-glucanases and chitinases in this study did not show any significant difference between treatments; suggesting that other genes encoding POD and PR proteins that were not selected may be involved. After 17 weeks following the inoculation of the plants with the pathogen Foa, treatment with alginate reduced the mortality rate by up to 80% compared to the rate in control plants (non-elicited) and plants pretreated with laminarin, which agrees with the induction of defense gene expression and the stimulation of natural defenses in date palm with alginate after 24 h. These results open promising prospects for the use of alginate in agriculture as an inducer that triggers immunity of plants against telluric pathogens in general and of date palm against Fusarium oxysporum f. sp. albedinis in particular.


Assuntos
Alginatos/farmacologia , Phaeophyceae/química , Phoeniceae/microbiologia , Doenças das Plantas/prevenção & controle , Alginatos/isolamento & purificação , Fusariose/prevenção & controle , Fusarium/isolamento & purificação , Regulação da Expressão Gênica de Plantas/genética , Glucanos/farmacologia , Lipoxigenase/metabolismo , Phoeniceae/genética , Doenças das Plantas/microbiologia , Metabolismo Secundário , Superóxido Dismutase/metabolismo
2.
Sci Rep ; 11(1): 16741, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408229

RESUMO

Alginates derived from macroalgae have been widely used in a variety of applications due to their stability, biodegradability and biocompatibility. Alginate was extracted from Egyptian Sargassum latifolium thallus yielding 17.5% w/w. The chemical composition of S. latifolium is rich in total sugars (41.08%) and uronic acids (47.4%); while, proteins, lipids and sulfates contents are 4.61, 1.13 and 0.09%, respectively. NMR, FTIR and TGA analyses were also performed. Crystallinity index (0.334) indicates alginate semicrystalline nature. Sodium alginate hydrolysate was evaluated as Chlorella vulgaris growth promoter. The highest stimulation (0.7 g/L biomass) was achieved by using 0.3 g/L alginate hydrolysate supplementation. The highest total soluble proteins and total carbohydrates were 179.22 mg/g dry wt and 620.33 mg/g dry wt, respectively. The highest total phenolics content (27.697 mg/g dry wt.), guaiacol peroxidase activity (2.899 µmol min-1 g-1) were recorded also to 0.3 g/L alginate hydrolysate supplementation. Riboflavin-entrapped barium alginate-Arabic gum polymeric matrix (beads) was formulated to achieve 89.15% optimum drug entrapment efficiency (EE%). All formulations exhibited prolonged riboflavin release over 120 min in simulated gastric fluid, followed Higuchi model (R2 = 0.962-0.887) and Korsmeyer-Peppas model with Fickian release (n ranges from 0.204 to 0.3885).


Assuntos
Alginatos , Chlorella vulgaris/crescimento & desenvolvimento , Sistemas de Liberação de Medicamentos , Riboflavina/química , Sargassum/química , Alginatos/química , Alginatos/isolamento & purificação , Alginatos/farmacologia
3.
Molecules ; 26(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34443312

RESUMO

Subcritical water extraction of Himanthalia elongata and the subsequent acetone fractionation to precipitate crude fucoidans generated a liquid phase which was used to recover alginates with a wide range of viscoelastic features and other soluble extracts with potential biological activities. The precipitated alginate was converted to sodium alginate using an environmentally friendly treatment before being characterized by Fourier transform infrared attenuated total reflectance, nuclear magnetic resonance, high performance size exclusion chromatography and rheological measurements. The cell viability of three human cell lines (A549, HCT-116, T98G) in the presence of the extracts obtained before and after acetone fractionation was assessed. Fractionation with different acetone volumes showed a slight effect in the behavior of the different tested cell lines. Results also indicated a notable effect of the processing conditions on the block structure and molar mass of the extracted biopolymer, with the subsequent impact on the rheological properties of the corresponding gelled matrices.


Assuntos
Alginatos/isolamento & purificação , Phaeophyceae/química , Água/química , Alginatos/química , Alginatos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Conformação Molecular , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
4.
Int J Biol Macromol ; 186: 656-685, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271047

RESUMO

Biomaterials are being extensively used in regenerative medicine including tissue engineering applications, as these enhance tissue development, repair, and help in the process of angiogenesis. Wound healing is a crucial biological process of regeneration of ruptured tissue after getting injury to the skin and other soft tissue in humans and animals. Besides, the accumulation of microbial biofilms around the wound surface can increase the risk and physically obstruct the wound healing activity, and may even lead to amputation. Hence, in both acute and chronic wounds, prominent biomaterials are required for wound healing along with antimicrobial agents. This review comprehensively addresses the antimicrobial and wound healing effects of chitosan, chitin, cellulose acetate, hyaluronic acid, pullulan, bacterial cellulose, fibrin, alginate, etc. based wound dressing biomaterials fabricated with natural resources such as honey, plant bioactive compounds, and marine-based polymers. Due to their excellent biocompatibility and biodegradability, bioactive compounds derived from honey, plants, and marine resources are commonly used in biomedical and tissue engineering applications. Different types of polymer-based biomaterials including hydrogel, film, scaffold, nanofiber, and sponge dressings fabricated with bioactive agents including honey, curcumin, tannin, quercetin, andrographolide, gelatin, carrageenan, etc., can exhibit significant wound healing process in, diabetic wounds, diabetic ulcers, and burns, and help in cartilage repair along with good biocompatibility and antimicrobial effects. Among the reviewed biomaterials, carbohydrate polymers such as chitosan-based biomaterials are prominent and widely used for wound healing applications followed by hyaluronic acid and alginate-based biomaterials loaded with honey, plant, and marine compounds. This review first provides an overview of the vast natural resources used to formulate different biomaterials for the treatment of antimicrobial, acute, and chronic wound healing processes.


Assuntos
Anti-Infecciosos/farmacologia , Organismos Aquáticos , Bandagens , Mel , Extratos Vegetais/farmacologia , Polímeros/farmacologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Alginatos/isolamento & purificação , Alginatos/farmacologia , Animais , Anti-Infecciosos/isolamento & purificação , Organismos Aquáticos/química , Quitosana/isolamento & purificação , Quitosana/farmacologia , Portadores de Fármacos , Composição de Medicamentos , Humanos , Ácido Hialurônico/isolamento & purificação , Ácido Hialurônico/farmacologia , Extratos Vegetais/isolamento & purificação , Polímeros/isolamento & purificação , Pele/lesões , Pele/microbiologia , Pele/patologia , Ferimentos e Lesões/microbiologia , Ferimentos e Lesões/patologia
5.
Mar Drugs ; 19(5)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068547

RESUMO

Alginates are naturally occurring polysaccharides extracted from brown marine algae and bacteria. Being biocompatible, biodegradable, non-toxic and easy to gel, alginates can be processed into various forms, such as hydrogels, microspheres, fibers and sponges, and have been widely applied in biomedical field. The present review provides an overview of the properties and processing methods of alginates, as well as their applications in wound healing, tissue repair and drug delivery in recent years.


Assuntos
Alginatos/química , Alginatos/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Alginatos/isolamento & purificação , Animais , Materiais Biocompatíveis/isolamento & purificação , Materiais Biomédicos e Odontológicos/química , Materiais Biomédicos e Odontológicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Impressão Tridimensional , Engenharia Tecidual , Cicatrização
6.
Carbohydr Polym ; 267: 118158, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119132

RESUMO

Alginate is a biopolymer used extensively in the food, pharmaceutical, and chemical industries. Alginate oligosaccharides (AOS) derived from alginate exhibit superior biological activities and therapeutic potential. Alginate lyases with characteristic substrate specificity can facilitate the production of a broad array of AOS with precise structure and functionality. By adopting innovative analytical tools in conjunction with focused clinical studies, the structure-bioactivity relationship of a number of AOS has been brought to light. This review covers fundamental aspects and recent developments in AOS research. Enzymatic and microbial processes involved in AOS production from brown algae and sequential steps involved in AOS structure elucidation are outlined. Biological mechanisms underlying the health benefits of AOS and their potential industrial and therapeutic applications are elaborated. Withal, various challenges in AOS research are traced out, and future directions, specifically on recombinant systems for AOS preparation, are delineated to further widen the horizon of these exceptional oligosaccharides.


Assuntos
Alginatos/uso terapêutico , Oligossacarídeos/uso terapêutico , Alginatos/química , Alginatos/isolamento & purificação , Animais , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Humanos , Engenharia Metabólica , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Polissacarídeo-Liases/química , Engenharia de Proteínas
7.
Int J Biol Macromol ; 167: 1135-1145, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33188815

RESUMO

Brown seaweeds are rich source of functional polysaccharides that exhibit various bioactivities. However, Malaysian seaweeds are under-utilised, leading to low revenue throughout the supply chain of the seaweed industry. The aims of this study were to extract the functional polysaccharides, namely fucoidan (F), laminaran (L) and alginate (A) from Malaysian brown seaweeds (Sargassum polycystum, Turbinaria ornata and Padina boryana) and subsequently evaluate the properties of the extracted polysaccharides. P. boryana recorded the significantly (p ≤ 0.05) highest carbohydrate content (74.78 ± 1.63%) with highest fucoidan yield (Fpad = 1.59 ± 0.16%) while T. ornata contained significantly (p ≤ 0.05) highest alginate yield (Atur = 105.19 ± 3.45%). Water activities of these extracted polysaccharides varied from 0.63-0.71 with average score of browning indexes (~40). Fourier transform infrared (FTIR) spectroscopy analysis demonstrated that the extracted polysaccharides exhibited similar spectral pattern of spectra with the respective standards. Meanwhile, laminaran extracts showed the significantly highest (p ≤ 0.05) total phenolic contents (Lsar = 43.29 ± 0.43 mgGAE/g) and superoxide anion scavenging activity (Lsig = 21.7 ± 3.6%). On the other hand, the significantly highest (p ≤ 0.05) DPPH scavenging activity was recorded in alginate with Asar at 85.3 ± 0.8%. These findings reported the properties and bioactivities of natural polysaccharides from Malaysian brown seaweeds that revealed the potential to develop high-value functional ingredients from Malaysian brown seaweeds.


Assuntos
Alginatos/química , Glucanos/química , Polissacarídeos/química , Sargassum/química , Alga Marinha/química , Alginatos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fracionamento Químico , Fenômenos Químicos , Fibras na Dieta/análise , Glucanos/isolamento & purificação , Fenóis/química , Polissacarídeos/análise , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Análise Espectral
8.
Carbohydr Polym ; 251: 116992, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142563

RESUMO

Alginate only finds industrial applicability after undergoing a bleaching process to improve its visual appearance. Box-Behnken Design was used to optimize bleaching parameters (time, oxygen flow and temperature) for sodium alginate (SA) extracted from seaweeds using ozone as the bleaching agent. The optimal conditions (oxygen flow 2 L/min for 35 min at 25 °C) resulted in an ozone-bleached SA with a mannuronic/guluronic acids ratio of 0.70, viscosity-average molecular weight of 66.30 kDa and dynamic viscosity of 1.39 mPa.s, aligned to strong and brittle gels formation, which are potentially suitable for hydrogels and bioink application. Results indicated that ozonation caused depolymerization of the SA chain. Colorimetric parameters showed that ozone has a great bleaching efficacy. The bleached sample presented high antioxidant capacity, highlighting that discoloration by ozone might have minimal effects on the bioactive compounds which are valuable ingredients for food-based products.


Assuntos
Alginatos/isolamento & purificação , Phaeophyceae/química , Alga Marinha/química , Alginatos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Clareadores , Colorimetria , Aditivos Alimentares/química , Aditivos Alimentares/isolamento & purificação , Humanos , Hidrogéis , Tinta , Peso Molecular , Ozônio , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade
9.
Carbohydr Polym ; 252: 117221, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183647

RESUMO

Seaweed is a prominent source of polysaccharides with extraction processes properly established, allowing to employ them in several areas. Among all the types of biopolymers obtained from seaweed, furcellaran has gained notoriety in recent years. This is due to its abundance, water solubility and outstanding film-forming abilities. Despite still being little studied, in several works, remarkable advances in terms of improving properties of furcellaran-based films have been described in the literature. However, there are still numerous research opportunities to be explored regarding the improvement of material properties. Therefore, the objective of this review is to highlight the innovative method in preparation, characterization and performance of furcellaran-based films as food packaging. This is the first study in which current results in the area are presented. Initially, it concerns biopolymer chemical and extraction insights. In addition, a comprehensive description of the advances in film properties is outlined (from mechanical to active/intelligent responses). Ultimately, challenges and future prospects are also discussed.


Assuntos
Alginatos , Anti-Infecciosos , Antioxidantes , Filmes Comestíveis , Embalagem de Alimentos , Gomas Vegetais , Alginatos/química , Alginatos/isolamento & purificação , Alginatos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Fenômenos Mecânicos , Gomas Vegetais/química , Gomas Vegetais/isolamento & purificação , Gomas Vegetais/farmacologia
10.
Mar Drugs ; 18(10)2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33086600

RESUMO

Polysaccharides extracted from marine algae have attracted much attention due to their biotechnological applications, including therapeutics, cosmetics, and mainly in agriculture and horticulture as biostimulants, biofertilizers, and stimulators of the natural defenses of plants. This study aimed to evaluate the ability of alginate isolated from Bifurcaria bifurcata from the Moroccan coast and oligoalginates derivatives to stimulate the natural defenses of tomato seedlings. Elicitation was carried out by the internodal injection of bioelicitor solutions. The elicitor capacities were evaluated by monitoring the activity of phenylalanine ammonia-lyase (PAL) as well as polyphenols content in the leaves located above the elicitation site for 5 days. Alginate and oligoalginates treatments triggered plant defense responses, which showed their capacity to significantly induce the PAL activity and phenolic compounds accumulation in the leaves of tomato seedlings. Elicitation by alginates and oligoalginates showed an intensive induction of PAL activity, increasing from 12 h of treatment and remaining at high levels throughout the period of treatment. The amount of polyphenols in the leaves was increased rapidly and strongly from 12 h of elicitation by both saccharide solutions, representing peaks value after 24 h of application. Oligoalginates exhibited an effective elicitor capacity in polyphenols accumulation compared to alginate polymers. The alginate and oligosaccharides derivatives revealed a similar elicitor capacity in PAL activity whereas the accumulation of phenolic compounds showed a differential effect. Polysaccharides extracted from the brown seaweed Bifurcaria bifurcate and oligosaccharides derivatives induced significantly the phenylpropanoid metabolism in tomato seedlings. These results contribute to the valorization of marine biomass as a potential bioresource for plant protection against phytopathogens in the context of eco-sustainable green technology.


Assuntos
Alginatos/farmacologia , Oligossacarídeos/farmacologia , Phaeophyceae/química , Substâncias Protetoras/farmacologia , Plântula/metabolismo , Solanum lycopersicum/química , Solanum lycopersicum/metabolismo , Alginatos/química , Alginatos/isolamento & purificação , Marrocos , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Fenilalanina Amônia-Liase/análise , Fenilalanina Amônia-Liase/efeitos dos fármacos , Fenilalanina Amônia-Liase/isolamento & purificação , Folhas de Planta/química , Polifenóis/análise , Polifenóis/isolamento & purificação , Polifenóis/metabolismo , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Metabolismo Secundário , Plântula/química
11.
Molecules ; 25(18)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971782

RESUMO

Alginates are widely used as gelling agents in textile print pastes, medical industries, impression material in dentistry, and anticoagulant material in toothpaste. In the present study, the content and spectroscopic characterization (1H NMR and FT-IR) of the sodium alginates were investigated in the eight brown seaweeds Sargassum muticum, Fucus vesiculosus f. volubilis, Carpodesmia tamariscifolia, Bifurcaria bifurcata, Laminaria ochroleuca, Cystoseira humilis, Saccorhiza polyschides, and Fucus guiryi harvested from the NW Atlantic coast of Morocco. The results proved that the most studied algae depicted alginate yields higher than 18% dry weight. The FT-IR analysis showed that the spectra of the extracted alginates exhibited significant similarities to the commercial alginate from Sigma-Aldrich. The 1H NMR spectroscopy indicated that the extracted alginates have a high content of ß-d-mannuronic (M) than α-l-guluronic acid (G) with M/G ratio values ranging from 1.04 to 4.41. The homopolymeric fractions FMM are remarkably high compared to the FGG and heteropolymeric fractions (FGM = FMG) especially for F. guiryi, C humilis, C. tamariscifolia, L. ochroleuca, and S. polyschides. Nevertheless, the heteropolymeric fractions (FGM/FMG) are quite abundant in the alginates of S. muticum, F. vesiculosus f. volubilis, and B. bifurcata accounting for more than 52% of the polymer diads. Based on these results, the investigated algal species (except Fucus guiryi and Bifurcaria bifurcata) could be regarded as potential sources of alginates for industrial uses.


Assuntos
Alginatos/química , Alginatos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Alga Marinha/química , Espectroscopia de Infravermelho com Transformada de Fourier , Oceano Atlântico , Marrocos
12.
Carbohydr Polym ; 245: 116419, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32718593

RESUMO

Sargassum valorization has become increasingly important as the Caribbean region continues to struggle with the massive growth of the seaweed and its damaging effects. Sodium alginate extraction is one method where the seaweed biomass can be utilized to produce a useful biopolymer. However, current processing generally giving low yields of inferior quality, making it unattractive for commercialization. This article seeks to optimize the extraction process using a Box-Behnken Response Surface Design combined with multistage extraction to obtain higher product yield and purity, as well as giving insights, for the first time, into the physiochemical properties of the extracted alginate from Sargassum biomass. Optimum conditions were found and confirmed through validation, with a crude yield as high as 28 % after 2 stages and a purity of 92 % for purified alginate samples. Characterization of the bleached alginate through NMR studies validated with FTIR, gave an M/G ratio of 0.45 with a molecular weight of 3.14 × 105 g mol-1 and viscosity of 14.10 cP aligned to high gelling capabilities.


Assuntos
Alginatos/química , Alginatos/isolamento & purificação , Sargassum/química , Alga Marinha/química , Biomassa , Biopolímeros/química , Região do Caribe , Espectroscopia de Ressonância Magnética , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Viscosidade
13.
Carbohydr Polym ; 245: 116547, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32718640

RESUMO

In this report, polysaccharides - alginate, fucoidan, laminaran - were isolated from marine algae Saccharina cichorioides and Fucus evanescens and their activity as a reducing and stabilizing agents in the biogenic synthesis of silver nanoparticles was evaluated. The cytotoxic and antibacterial properties of obtained nanoparticles were also assessed. It was found that all tested polysaccharides could be used as a reducing agent; however, their catalytic activities varied significantly in the following range alginate < fucoidan < laminaran. Nanoparticles demonstrated cytotoxicity against rat C6 glioma cells. It was considerably higher for alginate- and laminaran-obtained nanosilver samples compared to fucoidan. Additionally, silver nanoparticles possessed considerable antibacterial properties more pronounced in fucoidan-obtained samples. Our data demonstrate that different algal polysaccharides can be used for the synthesis of silver nanoparticles with varying bioactivities.


Assuntos
Alginatos/química , Antibacterianos/química , Excipientes/química , Glucanos/química , Nanopartículas Metálicas/química , Phaeophyceae/química , Polissacarídeos/química , Substâncias Redutoras/química , Prata/química , Agrobacterium tumefaciens/efeitos dos fármacos , Alginatos/isolamento & purificação , Animais , Antibacterianos/farmacologia , Catálise , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Glucanos/isolamento & purificação , Polissacarídeos/isolamento & purificação , Ratos , Alga Marinha/química
14.
Mar Drugs ; 18(7)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605020

RESUMO

A green extraction process using only water was proposed for the simultaneous extraction of alginate and bioactive compounds from Laminaria ochroleuca. Operation was carried out during non-isothermal heating up to maximal temperatures over the range of 70 °C to 100 °C. Once separated, the alginate and the crude extract were characterised and the biological activities and cytotoxicity of the extracts was studied, the latter in intestinal epithelial cells. Those alginates obtained at 90 °C exhibited the highest extraction yields and viscoelastic features of the corresponding hydrogels. The obtained results show that the extracts obtained by non-isothermal extraction were suitable to formulate nanoparticles, which showed the smallest size (≈ 250-350 nm) when the higher content of fucoidan extract was present. Given the evidenced properties, the extracts may find an application in the formulation of nanoparticulate carriers for drug delivery.


Assuntos
Misturas Complexas/química , Química Verde/métodos , Laminaria/química , Nanopartículas/química , Polímeros/química , Alginatos/química , Alginatos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular , Células HCT116 , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Food Funct ; 11(3): 2704-2713, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32163080

RESUMO

Marine seaweed polysaccharides have been considered as a potential resource for antiallergic therapy. Alginate is an acidic linear polysaccharide and soluble dietary fiber that was extracted from brown algae, Laminaria japonica. The molecular weight of alginate was 108 kDa, and its water solution exhibited non-Newtonian characteristics, including viscoelasticity and shear-thinning behavior. The ability of alginate to inhibit allergic reactions was investigated in ovalbumin (OVA)-induced BALB/c mice, which have been widely used as a mouse model of egg allergy. The results showed that alginate could effectively attenuate the occurrence of allergic reactions, including improving the integrity of the intestinal epithelial villi and inhibition of mast cell degranulation in the jejunum, in OVA-induced mice. Moreover, after treatment with alginate, the levels of IgE, histamine and IL-4 in OVA-induced mice were remarkably decreased, and the levels of IFN-γ were markedly increased. In addition, the number of Treg cells in spleen tissues in OVA-induced mice was increased by alginate, and the OVA-induced differentiation of Th0 cells into Th2 cells was significantly inhibited. These results demonstrate that alginate possesses potential antiallergic activities in a mouse model of egg allergy, which might provide important evidence that alginate, extracted from Laminaria japonica, can be developed into a novel functional food for inhibiting egg allergy.


Assuntos
Alginatos/farmacologia , Antialérgicos/farmacologia , Hipersensibilidade a Ovo , Alginatos/isolamento & purificação , Animais , Antialérgicos/isolamento & purificação , Modelos Animais de Doenças , Duodeno/citologia , Duodeno/efeitos dos fármacos , Hipersensibilidade a Ovo/metabolismo , Hipersensibilidade a Ovo/prevenção & controle , Feminino , Histamina/metabolismo , Imunoglobulina E/metabolismo , Laminaria/química , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/efeitos adversos , Baço/citologia , Baço/efeitos dos fármacos , Subpopulações de Linfócitos T/efeitos dos fármacos
16.
Int J Biol Macromol ; 136: 386-394, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31173834

RESUMO

In recent years, there has been considerable interest in essential oils encapsulation and in developing biodegradable microparticles. The aim of this present work was to prepare clove essential oil loaded microspheres, by a modified emulsification method, using sodium alginate extracted from a Tunisian Brown seaweed Algae Padina pavonica as biopolymer. The obtained microparticles were characterized by FT-IR, DSC and SEM. Loading capacity yield, encapsulation efficiency (%EE) and in vitro release of the essential oil were also investigated. Sodium alginate microspheres were successfully prepared as confirmed by physico-chemical characterizations. %yield of microspheres and %EE of essential oil were 72.73% and 24.77% ±â€¯7.47%, respectively. SEM showed pseudospherical microspheres with rough surface ranging, in size, from 1500 µm to 3000 µm. In vitro dissolution study indicates a controlled released of the essential oil which follows, mainly, classical Fickian diffusion. Thus, this present work highlighted the potential of this polysaccharide as a biopolymer to formulate polymeric microspheres.


Assuntos
Alginatos/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Microesferas , Óleos Voláteis/química , Phaeophyceae/química , Alginatos/isolamento & purificação , Cápsulas
17.
Mar Biotechnol (NY) ; 21(4): 503-514, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31111339

RESUMO

Although alginate is known as an immunostimulant in shrimp, the comprehensive and simultaneous study on its activity to resolve the relationship of the hematological parameters, upregulation of immune-related gene expression, and resistance to pathogen has not been found in shrimp. We performed experiments to evaluate the effect and mechanism of alginate from S. siliquosum on Pacific white shrimp immune system. Hematological parameters were examined after oral administration of Na alginate in the shrimp. White spot syndrome virus (WSSV) was injected to the shrimp at 14 days, and its copy number was examined quantitatively (qRT-PCR). Immune-related gene expression was evaluated by qRT-PCR. Alginate increased some hematological immune parameters of shrimp. Before WSSV infection, expression levels of Toll and lectin genes were upregulated. The lectin gene were upregulated post infection, and the Toll gene in all the treatments were downregulated, except the shrimps fed with alginate at 6.0 g kg-1 at 48 h post infection (hpi). The shrimps fed with alginate at 6.0 g kg-1 were the most resistant and gave the least WSSV copy number at 48 hpi. Resistance of shrimps fed the alginate-supplemented diets against WSSV was significantly higher compared to that of the control treatment with 56% and 10% of survival rates, respectively. Oral administration of alginate did not affect the growth and total protein plasma. At 120 h post challenge, alginate treatment at 6.0 g kg-1 exhibited the highest survival rate. It is concluded that oral administration of alginate enhanced the innate immunity by upregulating immune-related gene expression. Consequently, the enhancement of the shrimp innate immunity improves the resistance against WSSV infection.


Assuntos
Alginatos/administração & dosagem , Resistência à Doença/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Penaeidae/efeitos dos fármacos , Sargassum/química , Vírus da Síndrome da Mancha Branca 1/efeitos dos fármacos , Administração Oral , Alginatos/isolamento & purificação , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Resistência à Doença/genética , Dosagem de Genes , Regulação da Expressão Gênica , Genes Virais/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Lectinas/genética , Lectinas/imunologia , Penaeidae/genética , Penaeidae/imunologia , Penaeidae/virologia , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Vírus da Síndrome da Mancha Branca 1/genética , Vírus da Síndrome da Mancha Branca 1/metabolismo
18.
Carbohydr Polym ; 217: 152-159, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079672

RESUMO

Composite biomaterials offer a new approach for engineering novel, minimally-invasive scaffolds with properties that can be modified for a range of soft tissue applications. In this study, a new way of controlling the gelation of alginate hydrogels using Ga-based glass particles is presented. Through a comprehensive analysis, it was shown that the setting time, mechanical strength, stiffness and degradation properties of this composite can all be tailored for various applications. Specifically, the hydrogel generated through using a glass particle, wherein toxic aluminium is replaced with biocompatible gallium, exhibited enhanced properties. The material's stiffness matches that of soft tissues, while it displays a slow and tuneable gelation rate, making it a suitable candidate for minimally-invasive intra-vascular injection. In addition, it was also found that this composite can be tailored to deliver ions into the local cellular environment without affecting platelet adhesion or compromising viability of vascular cells in vitro.


Assuntos
Alginatos/química , Materiais Biocompatíveis/química , Gálio/química , Vidro/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Alginatos/isolamento & purificação , Alginatos/toxicidade , Animais , Aorta/citologia , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/toxicidade , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Módulo de Elasticidade , Células Endoteliais/efeitos dos fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Hidrogel de Polietilenoglicol-Dimetacrilato/toxicidade , Miócitos de Músculo Liso/efeitos dos fármacos , Engenharia Tecidual/métodos , Alicerces Teciduais/química
19.
Mar Drugs ; 17(3)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30889794

RESUMO

Alginate oligosaccharides (AlgO), agarose oligosaccharides (AO), and κ-carrageenan oligosaccharides (KCO) were obtained by specific enzymatic hydrolysis method. The molecular weight distributions of the three oligosaccharides were 1.0⁻5.0 kDa, 0.4⁻1.4 kDa, and 1.0⁻7.0 kDa, respectively. The culture medium was supplemented with the three oligosaccharides and fermented by pig fecal microbiota in vitro, for 24 h. Each oligosaccharide was capable of increasing the concentration of short-chain fatty acids (SCFAs), especially butyric acid, and altering the microbiota composition. Linear discriminant analysis effect size (LEfSe) analysis results showed that the opportunistic pathogenic bacteria Escherichia, Shigella, and Peptoniphilus, were significantly decreased in AlgO supplemented medium. AO could improve the gut microbiota composition by enriching the abundance of Ruminococcaceae, Coprococcus, Roseburia, and Faecalibacterium. Besides, KCO could increase the abundance of SCFA microbial producers and opportunistic pathogenic flora. Therefore, these results indicate that AlgO and AO can be used as gut microbial regulators and can potentially improve animal/human gastrointestinal health and prevent gut disease, whereas the physiological function of KCO needs further evaluation.


Assuntos
Organismos Aquáticos/química , Bactérias/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Oligossacarídeos/administração & dosagem , Prebióticos/administração & dosagem , Alginatos/administração & dosagem , Alginatos/química , Alginatos/isolamento & purificação , Animais , Bactérias/isolamento & purificação , Carragenina/administração & dosagem , Carragenina/química , Carragenina/isolamento & purificação , Fezes/microbiologia , Hidrólise , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Phaeophyceae/química , Rodófitas/química , Alga Marinha/química , Sefarose/administração & dosagem , Sefarose/química , Sefarose/isolamento & purificação , Suínos
20.
Dermatol Ther ; 32(1): e12779, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30371977

RESUMO

Although alginate has been known to be a good wound dressing, it does not have antimicrobial properties, has low availability, and is expensive. To overcome these problems, the present study was conducted, where the extraction of this material from an available small factory Pseudomonas aeruginosa and the improvement of its wound healing property by its combination with herb extract, Alhagi maurorum, done. Nineteen P. aeruginosa strains were isolated and identified from burned skin, and the one isolated strain with the highest ability of alginate production was selected. A. maurorum aqueous extract was prepared, and the toxicity of each material was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide assay. A mixture of nontoxic doses of each substance was then prepared. Thirty-two Wistar rats were divided into four groups (n = 8). The control group and the rest three groups, which were treated by alginate, A. maurorum extract, and alginate- A. maurorum extract. Throughout the 21 days of treatment, the open wound sites were checked. Finally, the rats were sacrificed and the effect of each substance on their skin tissue was evaluated. The results showed that the high alginate production without any toxic effect was obtained from the P. aeruginosa strain K1. A. maurorum aqueous extract had dose-dependent toxicity. The aqueous solution of alginate- A. maurorum extract complex group showed the best wound healing activity in both macroscopic and microscopic examinations. Recent research has introduced a new type of wound dressing with high wound healing properties. This could decrease the time for re-epithelialization and increase wound contraction percentage.


Assuntos
Alginatos/administração & dosagem , Fabaceae/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/química , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ferimentos Penetrantes/tratamento farmacológico , Administração Cutânea , Alginatos/isolamento & purificação , Animais , Modelos Animais de Doenças , Combinação de Medicamentos , Géis , Masculino , Extratos Vegetais/isolamento & purificação , Ratos Wistar , Reepitelização/efeitos dos fármacos , Pele/lesões , Pele/patologia , Fatores de Tempo , Ferimentos Penetrantes/patologia
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