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1.
J Appl Microbiol ; 127(6): 1716-1726, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31517429

RESUMO

AIMS: To purify and characterize an exopolysaccharide (EPS) from an Agrobacterium strain ZCC3656 with high EPS-secreting performance and investigate its anti-inflammatory activity using lipopolysaccharide (LPS)-induced macrophage cells in an acute liver injury mouse model. METHODS AND RESULTS: Twelve rhizobial strains were compared for EPS fermentation production in modified M9 salts supplemented with mannitol or sucrose as the sole carbon source. Agrobacterium sp. ZCC3656 exhibited the highest EPS yield (21·1 g l-1 ) and was characterized for EPS production by carbon source utilization, time course fermentation and serial subcultivation assays. The EPS, designated Riclin, was purified by deproteinization using the Sevag method. The combined results of gel permeation chromatography, monosaccharide composition, methylation analysis and nuclear magnetic resonance analyses indicated that Riclin is a succinoglycan-like polysaccharide comprised of glucose, galactose, succinate and pyruvate at a ratio of 7·8. : 1·0 : 0·9 : 1·1 and has an molecular weight of approximately 2·5 × 106  Da. Riclin inhibited TNF-α, IL-1ß and IL-6 expression in LPS-stimulated RAW 264.7 macrophage cells in a dose-dependent manner. In addition, Riclin pretreatment increased the survival rate of D-Gal/LPS treated mice, inhibited serum ALT and AST activities and reduced the production of the inflammatory mediators TNF-α, IL-1ß and IL-6. CONCLUSIONS: Agrobacterium sp. ZCC3656 is a highly stable EPS-producing strain. The EPS Riclin from ZCC3656 is a succinoglycan-type polysaccharide that is noncytotoxic and exhibits remarkable anti-inflammatory effects in vivo and in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: Succinoglycans are well known for good rheological properties and their physiological interactions with plants. However, their potential activity towards mammals has received little attention. Our study revealed that the succinoglycan Riclin exhibited excellent anti-inflammatory activities and could be considered as a promising reagent in anti-inflammatory treatment.


Assuntos
Agrobacterium/química , Anti-Inflamatórios/farmacologia , Macrófagos/efeitos dos fármacos , Polissacarídeos Bacterianos/farmacologia , Agrobacterium/metabolismo , Animais , Anti-Inflamatórios/química , Citocinas/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Masculino , Camundongos , Polissacarídeos Bacterianos/química , Células RAW 264.7
2.
J Agric Food Chem ; 67(35): 9831-9839, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31407897

RESUMO

Probiotic lactobacilli and their exopolysaccharides (EPS) are thought to modulate mucosal homeostasis; however, their mechanisms remain elusive. Thus, we tried to clarify the role of exopolysaccharides from Lactobacillus plantarum NCU116 (EPS116) in the intestinal mucosal homeostasis. Our results indicated that EPS116 regulated the colon mucosal healing and homeostasis, enhanced the goblet cell differentiation, and promoted the expression of Muc2 gene in vivo and in vitro. Further experiments showed that EPS116 promoted the expression and phosphorylation of transcription factor c-Jun and facilitated its binding to the promoter of Muc2. Moreover, knocking down c-Jun or inhibiting its function in LS 174T cells treated with EPS116 led to decreased expression of Muc2, implying that EPS116 promoted the colonic mucosal homeostasis and Muc2 expression via c-Jun. Therefore, our study uncovered a novel model where EPS116 enhanced colon mucosal homeostasis by controlling the epithelial cell differentiation and c-Jun/Muc2 signaling.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Colo/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Lactobacillus plantarum/química , Mucina-2/metabolismo , Polissacarídeos Bacterianos/farmacologia , Proteínas Proto-Oncogênicas c-jun/metabolismo , Animais , Linhagem Celular Tumoral , Colo/citologia , Colo/metabolismo , Colo/fisiopatologia , Homeostase/efeitos dos fármacos , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mucina-2/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-jun/genética , Transdução de Sinais/efeitos dos fármacos
3.
Molecules ; 24(16)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426284

RESUMO

Allergic disease is one of the most important and common health problems worldwide. We have previously demonstrated that a fig leaf-derived lactic acid bacterium Lactobacillus (Lb.) paracasei IJH-SONE68 produces a novel exopolysaccharide (EPS). Furthermore, we have shown that the EPS inhibits the catalytic activity of hyaluronidase (EC 3.2.1.36) promoting inflammatory reactions. To evaluate the anti-allergy and anti-inflammatory effects of the EPS, in the present study, we employed the picryl-chloride-induced delayed-type (type IV) allergy model mice, which is used to evaluate the contact dermatitis. Oral administration of the EPS was observed to reduce the ear swelling in the model mice. We also observed that the overexpression of ear interleukin-4 (T helper (Th) 2 cytokine) mRNA and the increase in serum immunoglobulin E (IgE) are repressed. However, the expression of interferon-γ (Th1 cytokine) was not accelerated in all of the allergen-challenged model mice. The improvement may be responsible for the Th2 downregulation rather than the Th1 upregulation. In addition, the symptom of immediate-type (type I) allergy model mice was improved by oral administration of the IJH-SONE68 cell (data not shown). We can conclude that the IJH-SONE68-derived EPS is useful to improve the type I and IV allergies including atopic dermatitis.


Assuntos
Antialérgicos/farmacologia , Anti-Inflamatórios/farmacologia , Dermatite de Contato/prevenção & controle , Fármacos Dermatológicos/farmacologia , Lactobacillus paracasei/química , Polissacarídeos Bacterianos/farmacologia , Administração Oral , Alérgenos/imunologia , Alérgenos/metabolismo , Animais , Antialérgicos/isolamento & purificação , Anti-Inflamatórios/isolamento & purificação , Dermatite de Contato/etiologia , Dermatite de Contato/imunologia , Dermatite de Contato/patologia , Fármacos Dermatológicos/isolamento & purificação , Modelos Animais de Doenças , Orelha , Expressão Gênica/efeitos dos fármacos , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/imunologia , Hialuronoglucosaminidase/metabolismo , Imunoglobulina E/sangue , Imunoglobulina E/genética , Interferon gama/genética , Interferon gama/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Lactobacillus paracasei/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Cloreto de Picrila/administração & dosagem , Polissacarídeos Bacterianos/isolamento & purificação , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia
4.
Int J Radiat Biol ; 95(11): 1552-1563, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31348725

RESUMO

Purpose: To assess exopolysaccharides (EPS) of Bacillus siamensis CV5, isolated from irradiated roots of Cistanche violacea, for their induction by ionizing radiation (IR) and their antioxidant and radioprotective power.Materials and methods: Isolated bacteria from the roots of C. violacea were screened for EPS production. The most EPS-producing bacterium was selected and the response surface methodology (RSM) was applied to elucidate the IR dose effects on EPS production. Gamma irradiation effects on the morphology and functional groups of EPS were studied using microscopy and Fourier transform infra-red (FT-IR). The radioprotective potential of EPS on the survival of B. siamensis CV5 following IR was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Free radicals scavenging potentialities (FRSP) of non-irradiated and irradiated EPS were evaluated through 2, 2--diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and ferric reducing ability of plasma (FRAP) assays.Results: Twenty strains, isolated from irradiated roots of C. violacea, were screened for their EPS production. IR-resistant B. siamensis CV5 was the most EPS-producing strain. Its purified EPS contained rhamnose, fructose, mannose and glucose. RSM indicated that EPS of CV5 (CV5-EPS) are radiation inducible. Micrographs of CV5-EPS suggested an increase in the total area and a decrease in the Feret's statistical diameter following exposure to IR. FT-IR spectra of these EPS revealed an increase of various functional groups. The MTT survival assay demonstrated a positive correlation between the added quantity of CV5-EPS and the viability of irradiated CV5 (p < .01). DPPH, ABTS and FRAP assays indicated that the antioxidant activities of CV5-EPS increased significantly with the irradiation dose (p < .01).Conclusions: CV5-EPS were demonstrated as radiation-inducible and radioprotective biomolecules. This radioprotective potential of CV5-EPS could be associated with their antioxidant activities. In the future, irradiated EPS could be tested as a gel in cancer radiotherapy for minimizing the damage caused by rays to surrounding healthy tissues.


Assuntos
Bacillus/metabolismo , Bacillus/efeitos da radiação , Cistanche/microbiologia , Polissacarídeos Bacterianos/farmacologia , Protetores contra Radiação/farmacologia , Antioxidantes/química , Cistanche/efeitos da radiação , Depuradores de Radicais Livres/farmacologia , Radicais Livres , Raios gama , Raízes de Plantas/microbiologia , Raízes de Plantas/efeitos da radiação , Doses de Radiação , Radiação Ionizante
5.
Mater Sci Eng C Mater Biol Appl ; 103: 109770, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349525

RESUMO

In this work, the potential of titanium dioxide nanoparticles incorporated gellan gum (GG + TiO2-NPs) biofilm as wound dressing material was investigated. The GG + TiO2-NPs biofilm was prepared via evaporative casting technique and was characterized using FTIR, XRD, and SEM to study their physiochemical properties. The mechanical properties, swelling and water vapor transmission rate (WVTR) of biofilm was determined to comply with an ideal wound dressing material. In vitro and in vivo wound healing studies was carried out to evaluate the performance of GG + TiO2-NPs biofilm. In vitro wound healing was studied on 3 T3 mouse fibroblast cells for cell viability, cell proliferation, and scratch assay. The acridine orange/propidium iodide (AO/PI) staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay were used to evaluate the viability of cell and cell proliferation. Cell migration assay was analyzed using Essen BioScience IncuCyteTM Zoom system. In vivo wound healing via open excision wounds model on Sprague Dawley rat was studied within 14 days. The FT-IR spectra of GG + TiO2-NPs biofilm show main bands assigned to OH stretching, OH deformation, and TiO stretching modes. XRD pattern of GG + TiO2-NPs biofilm suggesting that TiO2-NPs was successfully incorporated in biofilm and well distributed on the surface as proved by SEM analysis. The GG + TiO2-NPs biofilm shows higher mechanical strength and swelling (3.76 ±â€¯0.11 MPa and 1061 ±â€¯6%) as compared to pure GG film (3.32 ±â€¯0.08 Mpa and 902 ±â€¯6%), respectively. GG + TiO2-NPs biofilm shows good antibacterial properties as 9 ±â€¯0.25 mm and 11 ±â€¯0.06 mm exhibition zone was observed against Staphylococcus aureus and Escherichia coli bacteria, respectively. While no exhibition zone was obtained for pure GG biofilm. GG + TiO2-NPs biofilm also demonstrated better cell-to-cell interaction properties, as it's promoted cell proliferation and cell migration to accelerate open excision wound healing on Sprague Dawley rat. The wound treated with GG + TiO2-NPs biofilm was healed within 14 days, on the other hand, the wound is still can be seen when it was treated with GG. However, GG and GG + TiO2-NPs biofilm show no cytotoxicity effects on mouse fibroblast cells.


Assuntos
Antibacterianos , Bandagens , Escherichia coli/crescimento & desenvolvimento , Membranas Artificiais , Nanopartículas/química , Polissacarídeos Bacterianos , Staphylococcus aureus/crescimento & desenvolvimento , Titânio , Cicatrização/efeitos dos fármacos , Células 3T3 , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Camundongos , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Ratos , Ratos Sprague-Dawley , Titânio/química , Titânio/farmacologia
6.
Int Heart J ; 60(4): 964-973, 2019 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-31257333

RESUMO

Acute myocardial infarction (AMI) is a serious heart disease and the main reason for heart failure and sudden death worldwide. This study investigated the effects of polysaccharides from Enteromorpha prolifera (PEP) on AMI in vitro and in vivo, as well as the underlying mechanisms.Human cardiac microvascular endothelial cells (HCMVEC) were cultured in vitro in an oxygen-glucose deprivation (OGD) environment to induce injury. The viability and apoptosis of HCMVEC were then detected using CCK-8 assay and Annexin V-FITC/PI staining, respectively. ELISA was performed to measure the concentrations of inflammatory cytokines. Cell transfection was conducted to reduce the expression of HIF-1α. Expression of key factors involving in cell proliferation, apoptosis, autophagy, MEK/ERK, and the NF-κB and mTOR pathways were evaluated using Western blotting. In vivo, Wistar rats were pre-treated by PEP and AMI was induced. The infarct size and cardiac functions (LVEDD, LVEF and LVFS) were measured.In vitro, PEP treatment significantly protected HCMVEC from OGD-induced viability loss, proliferation inhibition, apoptosis, inflammatory cytokine expression, and autophagy. Moreover, PEP enhanced the expression of HIF-1α in HCMVEC via the MEK/ERK pathway. HIF-1α participated in the protective effects of PEP on OGD-treated HCMVEC. Furthermore, PEP attenuated OGD-induced NF-κB pathway activation and promoted the mTOR pathway in HCMVEC. In vivo, PEP pre-treatment reduced the infarct size and enhanced the LVEDD, LVEF and LVFS of rats via up-regulation of HIF-1α.PEP ameliorated AMI in vitro and in vivo through up-regulation of HIF-1α. In vitro, PEP could activate the MEK/ERK and mTOR pathways, but inactivate the NF-κB pathway in OGD-treated HCMVEC.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Infarto do Miocárdio/genética , Polissacarídeos Bacterianos/farmacologia , RNA/genética , Regulação para Cima , Animais , Apoptose , Western Blotting , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Ratos , Ratos Wistar , Transdução de Sinais
7.
Food Funct ; 10(6): 3738-3747, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31173024

RESUMO

The present study aimed to evaluate different mates of Candida boidinii and Lactobacillus pentosus strains as starters in green table olive fermentation. Changes in fermentation characteristics as well as changes in the functional properties of the microbial exopolysaccharides (EPS) produced during the process were registered. The in vitro adhesion test demonstrated that most EPS samples could specifically attach ETEC K88. In vitro studies with porcine intestinal cells showed the improved blocking activity of the fimbria (blocking test) when the mutant strain L. pentosus 119-14MT was used alone as a starter. All EPS samples showed the ability to block receptors in the cells (exclusion test) although without differences between starter treatments. In the displacement test, EPS samples failed to remove the pathogen once attached. According to these results, L. pentosus 119-14MT, a high EPS variant, seemed to be the most effective starter improving the anti-adhesive properties of brine EPS and increasing its ability to block the ETEC K88 fimbria. These results illustrate that the anti-adhesive properties of the EPSs produced during the traditional fermentation of olives could be modulated by the use of defined starters. This opens the door to new fermentation processes aimed to produce green table olives as functional food to prevent ETEC diarrhea.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Candida/metabolismo , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Lactobacillus pentosus/metabolismo , Olea/microbiologia , Polissacarídeos Bacterianos/farmacologia , Sais/química , Animais , Escherichia coli Enterotoxigênica/fisiologia , Infecções por Escherichia coli/microbiologia , Fermentação , Humanos , Intestinos/microbiologia , Polissacarídeos Bacterianos/metabolismo , Sais/farmacologia , Suínos
8.
Int J Biol Macromol ; 136: 436-444, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31201910

RESUMO

Leuconostoc mesenteroides S81 was isolated from traditional sourdough as an exopolysaccharide (EPS) producer strain. The monosaccharide composition of the EPS from strain S81 was characterized by HPLC analysis and only fructose was found in the repeating unit structure. The NMR spectroscopy analysis revealed that EPS was a levan type EPS as a ß-(2 → 6)-linked fructan. The FTIR analysis further confirmed the presence of the furanoid rings in the EPS structure. The levan S81 showed high level of thermal stability determined by DSC and TGA analysis. The lyophilised levan S81 showed a sheet-like compact morphology and its aqueous solution formed spheroidal lumps with a compact structure detected by SEM and AFM analysis, respectively. Importantly the levan S81 showed a high level of immunomodulatory role, induced the anti-inflammatory cytokine IL-4, and exhibited a strong antioxidant capacity with EC50 value 1.7 mg mL-1 obtained by hydroxyl radical scavenging activity test under in vitro conditions. These findings reveal potential of levan S81 for technological purposes and as a potential natural immunomodulatory and antioxidant.


Assuntos
Frutanos/química , Leuconostoc mesenteroides/metabolismo , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Fermentação , Células HT29 , Humanos , Fatores Imunológicos/biossíntese , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Peso Molecular , Polissacarídeos Bacterianos/biossíntese , Temperatura Ambiente , Água/química
9.
J Agric Food Chem ; 67(28): 8029-8034, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31246026

RESUMO

A special levan-type exopolysaccharide (EPS) from Bacillus amyloliquefaciens JN4 with antiadhesive activity against enterotoxigenic Escherichia coli (ETEC) was purified and identified. Chemical analysis indicated that EPS-JN4 with a low molecular weight of 8 kDa is composed of fructose and glucose with a molar ratio of 46.1:1. Structural analysis clarified that EPS-JN4 contains a main chain of ß-(2,6)-linked Fruf residues and intensive branches of a single 2-linked Fruf at every six residues. Furthermore, the superior antiadhesive activity of EPS-JN4 against ETEC showed its potential usage as an antiadhesive agent for diarrhea prevention. EPS-JN4 is a specific type of levan family, for its small molecular size and intensive branches. The results expand the knowledge on structural types of levan and illustrate its potential as an antiadhesive agent for diarrhea prevention, which will be conducive to elucidate the relation between structure and function.


Assuntos
Antibacterianos/farmacologia , Bacillus amyloliquefaciens/química , Aderência Bacteriana/efeitos dos fármacos , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Frutanos/farmacologia , Polissacarídeos Bacterianos/farmacologia , Antibacterianos/química , Antibacterianos/metabolismo , Bacillus amyloliquefaciens/metabolismo , Escherichia coli Enterotoxigênica/fisiologia , Frutanos/química , Frutanos/metabolismo , Espectroscopia de Ressonância Magnética , Peso Molecular , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo
10.
Int J Biol Macromol ; 133: 1090-1101, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054300

RESUMO

The aim of this study is to probe new functions of a polysaccharide from Spirulina platensis (PSP) on constipation and intestinal microbiota in mice. Diphenoxylate-induced constipation in mice was treated with different doses of PSP, followed by examining the defecation patterns, levels of acetyl cholinesterase (AchE), nitric oxide (NO), and tissue section histopathology. The composition of intestinal microbiota was determined by genome sequencing analysis of the 16S rDNA. This study found that the average molecular weight of PSP was 29, 600 Da, and mainly monosaccharides of PSP were rhamnose (24.7%), glucose (16.15%) and galactose (13.32%). The beneficial effects of PSP treatment include defecation improvement, increase of AchE activity, reduction of NO concentration, renovation of the damaged intestinal villus and affection on the expression of some related genes in the constipated mice. In addition, PSP had significant effects on the gut microbiota, showing the enhancement in abundance of beneficial bacteria including Akkermansia, Lactobacillus, Butyricimonas, Candidatus Arthromitus and Prevotella, and the reduction in abundance of harmful bacteria such as Clostridium and Dorea. The present s uncovered a new function of PSP, indicating that PSP could be used in constipation therapies.


Assuntos
Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Difenoxilato/efeitos adversos , Polissacarídeos Bacterianos/farmacologia , Spirulina/química , Animais , Vilosidades Coriônicas/efeitos dos fármacos , Vilosidades Coriônicas/metabolismo , Constipação Intestinal/metabolismo , Constipação Intestinal/fisiopatologia , Defecação/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neurotransmissores/metabolismo , Polissacarídeos Bacterianos/uso terapêutico , Água/metabolismo
11.
Int J Biol Macromol ; 134: 575-587, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31067487

RESUMO

In this study, we assessed the bio-functional attributes of an exopolysaccharide (EPS) produced by the actinobacterial probiont Streptomyces griseorubens GD5. The EPS production was doubled to 9.50 g/L by varying the concentration of media components using Response surface methodology. The physio-chemical properties of GD5EPS were examined by various analytical techniques. Several functional groups were detected in FT-IR spectra, including ß-glycosidic linkages, hydroxyl, carboxyl, and amide groups. Glucose, galactose, and mannose were detected from NMR spectra whilst the occurrence of arabinose, glucose, galactose, mannose, and xylose, were detected from HPLC chromatogram, signifying that GD5EPS is heteropolysaccharide in nature. The thermogram profile and SEM-EDX spectra of the extracted EPS indicated that it was highly thermo-stable, compact and porous, with flake-like structural units with the elemental composition of C, O, P, Mg, K, Ca, and Na. The GD5EPS also revealed potential antioxidant, emulsifying and antibiofilm efficacies, which corroborated that EPS derived from S. griseorubens GD5 might be a promising food supplement.


Assuntos
Polissacarídeos Bacterianos/farmacologia , Probióticos/química , Streptomyces/química , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Biofilmes/efeitos dos fármacos , Quelantes/química , Quelantes/farmacologia , Fenômenos Químicos , Monossacarídeos/química , Monossacarídeos/farmacologia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/ultraestrutura , Análise Espectral , Streptomyces/crescimento & desenvolvimento
12.
Int J Biol Macromol ; 134: 1013-1021, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31077696

RESUMO

Identification and rheological behaviour of succinoglycan exopolysaccharide (EPS) from Rhizobium radiobacter CAS isolated from curd was published in earlier reports. In current investigation physicochemical and functional properties of CAS EPS has been studied. SEC-MALLS revealed molecular weight (Mw), number molecular weight (Mn) and polydispersity index (PDI) of CAS EPS as 4.05×106g·mol-1, 3.82×106g·mol-1 and, 1.06 respectively. Thermogravimetric analysis showed the high thermal stability of CAS polymer where approximately 77% of CAS hydrocolloid maintain physical integrity and stability with temperature degradation (Td) at 290°C. Scanning electron microscopy and particle size analysis confirmed the porous and hygroscopic nature and 2.049µm size of CAS EPS respectively. Equally important functional properties such as water activity (0.55), water solubility (95%), water contact angle (54.83°), water binding capacity (101g/g), water holding capacity (68.19g/g), oil binding ability (soybean and groundnut oils were found 4.35g/g and 3.68g/g) and swelling index (17.5mL/g) were examined for CAS EPS. Prevention of syneresis has been studied at 1% CAS EPS concentration which significantly prohibited the degree of syneresis of starch. These physico-functional properties make CAS EPS a prominent candidate for food processing and product development sector.


Assuntos
Agrobacterium tumefaciens/química , Polissacarídeos Bacterianos/química , Agrobacterium tumefaciens/metabolismo , Fenômenos Químicos , Peso Molecular , Tamanho da Partícula , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/ultraestrutura , Solubilidade , Termogravimetria
13.
Carbohydr Polym ; 217: 79-89, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079688

RESUMO

Several scientific evidences have revealed probiotics implications on human health. A wide range of lactic acid bacteria (LAB) have been extensively studied for their ability to produce extracellular polysaccharides (EPSs), which are repeating units of mono/oligosaccharides with various chemical compositions and properties. Despite the conventional belief regarding probiotics that states bacteria must be alive to exert their beneficial effects, mounting evidence opened up new perspectives on health-promoting effects of bacterial-derived molecules/metabolites. Employing EPSs seems safer alternative in complicated disorders like cancer and immune related diseases. EPSs have potential applications in textiles, cosmetology, wastewater treatment, food, and pharmaceutical industries, but little is known about their function therefore the present review aims to discuss the health-promoting properties of EPSs produced by LAB. Antioxidant, antiviral, antitumor and immunomodulating activity, with focus on the mechanisms involved, are discussed in the study. Ever-growing number of researches indicate that EPSs beneficiary effects have a promising future ahead.


Assuntos
Antineoplásicos/uso terapêutico , Fatores Imunológicos/uso terapêutico , Lactobacillales/química , Polissacarídeos Bacterianos/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Sequência de Carboidratos , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia
14.
Int J Nanomedicine ; 14: 2557-2571, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118605

RESUMO

Introduction: Global increase in the consumption of antibiotics has induced selective stress on wild-type microorganisms, pushing them to adapt to conditions of higher antibiotic concentrations, and thus an increased variety of resistant bacterial strains have emerged. Metal nanoparticles synthesized by green methods have been studied and proposed as potential antimicrobial agents against both wild-type and antibiotic-resistant strains; in addition, exopolysaccharides have been used as capping agent of metal nanoparticles due to their biocompatibility, reducing biological risks in a wide variety of applications. Purpose: In this work, we use an exopolysaccharide, from Rhodotorula mucilaginosa UANL-001L, an autochthonous strain from the Mexican northeast, as a capping agent in the synthesis of Zn, and Ni, nanoparticle biopolymer biocomposites. Materials and methods: To physically and chemically characterize the synthesized biocomposites, FT-IR, UV-Vs, TEM, SAED and EDS analysis were carried out. Antimicrobial and antibiofilm biological activity were tested for the biocomposites against two resistant clinical strains, a Gram-positive Staphylococcus aureus, and a Gram-negative Pseudomonas aeruginosa. Antimicrobial activity was determined using a microdilution assay whereas antibiofilm activity was analyzed through crystal violet staining. Results: Biocomposites composed of exopolysaccharide capped Zn and Ni metal nanoparticles were synthesized through a green synthesis methodology. The average size of the Zn and Ni nanoparticles ranged between 8 and 26 nm, respectively. The Ni-EPS biocomposites showed antimicrobial and antibiofilm activity against resistant strains of Staphylococcus aureus and Pseudomonas aeruginosa at 3 and 2 mg/mL, respectively. Moreover, Zn-EPS biocomposites showed antimicrobial activity against resistant Staphylococcus aureus at 1 mg/mL. Both biocomposites showed no toxicity, as renal function showed no differences between treatments and control in the in vivo assays with male rats tests in this study at a concentration of 24 mg/kg of body weight. Conclusion: The exopolysaccharide produced by Rhodotorula mucilaginosa UANL-001L is an excellent candidate as a capping agent in the synthesis of biopolymer-metal nanoparticle biocomposites. Both Ni and Zn-EPS biocomposites demonstrate to be potential contenders as novel antimicrobial agents against both Gram-negative and Gram-positive clinically relevant resistant bacterial strains. Moreover, Ni-EPS biocomposites also showed antibiofilm activity, which makes them an interesting material to be used in different applications to counterattack global health problems due to the emergence of resistant microorganisms.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Biopolímeros/farmacologia , Nanopartículas Metálicas/química , Níquel/farmacologia , Polissacarídeos Bacterianos/farmacologia , Rhodotorula/metabolismo , Zinco/farmacologia , Animais , Antibacterianos/farmacologia , Masculino , Nanopartículas Metálicas/ultraestrutura , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos Wistar , Rhodotorula/efeitos dos fármacos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Int J Biol Macromol ; 133: 575-582, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31004639

RESUMO

Exopolysaccharides (EPSs) are metabolites of probiotics that have gained wide interest recently. A strain of Lactobacillus reuteri Mh-001 with high exopolysaccharide (EPS) production ability was isolated, identified, and were used to investigate the anti-inflammatory effects of the EPSs. Among the three unpurified EPSs, RAW246.7 murine macrophages treated with 5 ppm of EPS 1 revealed the lowest tumour necrosis factor α (TNF-α) secretion (325.32 ±â€¯51.10 pg/ug DNA). The second lowest TNF- α secretion occurred with EPS 2 (701.12 ±â€¯86.108 pg/ug DNA) from Mh-002. EPSs 4, 5, and 6 were further purified from EPS 1. Cells treated with 1 ppm of EPS 4 had the lowest TNF-α secretion of all (209.20 ±â€¯84.34 pg/ug DNA). The monosaccharide components, EPS 4 and EPS 1, had the highest galactose content (45 ±â€¯2.75% and 39 ±â€¯2.75%, respectively). The monosaccharide percentages (galactose > rhamnose > glucose) were related to the anti-inflammatory activity of the EPSs. The galactose content of EPSs enhanced their anti-inflammatory effects on the macrophages. These data indicate that EPS possesses beneficial physiological effects such as anti-inflammatory properties, and the monosaccharide content of the EPS was the factor influencing the anti-inflammatory properties.


Assuntos
Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Monossacarídeos/análise , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Probióticos/química , Animais , Relação Dose-Resposta a Droga , Hidrólise , Camundongos , Células RAW 264.7 , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/biossíntese
16.
J Dairy Sci ; 102(7): 5922-5932, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31030915

RESUMO

Exopolysaccharide (EPS) of Lactobacillus plantarum WLPL04 and its sulfated EPS were systematically investigated for their antioxidant activities and effects on protecting the oxidative damage of Caco-2 cells from H2O2. Exopolysaccharide was successfully sulfonated from purified EPS as confirmed by Fourier-transform infrared spectroscopy, and the degree of sulfonation was 0.30. Both EPS and sulfated EPS showed antioxidant activities in vitro determined by 1,1-diphenyl-2-picrylhydrazyl, superoxide, and hydroxyl radical scavenging tests, and those activities of sulfated EPS were significantly enhanced at 1,000 µg/mL. Cell viabilities of Caco-2 in the range of 1 to 100 µg/mL of EPS and sulfated EPS showed no significant difference. In H2O2-damaged Caco-2 cells models, EPS and sulfated EPS significantly inhibited the enhancement of reactive oxygen species and malondialdehyde levels, and sulfated EPS enhanced the effects by 40.86% and 61.11% when compared with the purified EPS at the same concentration of 100 µg/mL, respectively. For the activities of antioxidant-related enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and expression of genes (SOD2, GPX2, MT1M) on Caco-2 cells, strong protection abilities against the oxidative stress were displayed from both EPS and sulfated EPS, and sulfated EPS exhibited significant enhancement as compared with either EPS or control groups. In summary, sulfonation is an effective strategy for improving the antioxidant activities of EPS from L. plantarum WLPL04 in vitro and on Caco-2 cells.


Assuntos
Antioxidantes/farmacologia , Lactobacillus plantarum/química , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos Bacterianos/farmacologia , Substâncias Protetoras/farmacologia , Antioxidantes/química , Compostos de Bifenilo/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Humanos , Radical Hidroxila/química , Mucosa Intestinal/efeitos dos fármacos , Lactobacillus plantarum/isolamento & purificação , Picratos/química , Polissacarídeos Bacterianos/química , Substâncias Protetoras/química , Superóxidos/química
17.
Food Funct ; 10(3): 1707-1717, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30839970

RESUMO

Correlations between oxidative stress and degenerative diseases have been gaining increasing attention. A number of studies affirm that exopolysaccharide (EPS) produced by lactic acid bacteria (LAB) can alleviate oxidative stress and further prevent the related diseases. In our previous study, Lactobacillus helveticus KLDS1.8701 has been shown to possess high antioxidant capacity in vitro. The aim of this study was to evaluate the ameliorative effects of EPS produced by L. helveticus KLDS1.8701 on oxidative stress. Firstly, EPS was isolated from the culture of L. helveticus KLDS1.8701 and purified using DEAE-Sepharose Fast Flow chromatography. Secondly, the antioxidant capacities of EPS fractions were evaluated using in vitro methods. Thirdly, an in vivo study was performed to investigate the possible protective effects of EPS on d-galactose (d-gal)-induced liver damage and gut microbiota disorder. In vitro antioxidant activity results suggested that EPS-1 exhibited strong scavenging properties on 2,2-diphenyl-1-picrylhydrazyl radical, superoxide radical, hydroxyl radical, and chelating activity on ferrous ion. In vivo, EPS-1 supplementation significantly attenuated oxidative status such as decreased organic index, liver injury and liver oxidative stress. EPS-1 supplementation shifted the gut microbiota composition to that of the control group. In addition, the analysis of Spearman's rank correlation suggested that the protective effects of EPS correlated with manipulating the gut microbiota composition in d-gal-induced mice. These results implied that EPS-1 supplementation could mitigate hepatic oxidative stress via manipulating the gut microbiota composition and be used as a potential candidate to attenuate oxidative damage.


Assuntos
Lactobacillus helveticus/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos Bacterianos/farmacologia , Animais , Compostos de Bifenilo , Depuradores de Radicais Livres , Radical Hidroxila , Ferro/química , Quelantes de Ferro , Lactobacillus helveticus/classificação , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Picratos , Organismos Livres de Patógenos Específicos , Superóxidos
18.
Yakugaku Zasshi ; 139(3): 385-391, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-30828015

RESUMO

Sacran, a new polysaccharide isolated from cyanobacterium Aphanothece sacrum (Sur.) Okada, is known to have potential as an active pharmaceutical ingredient (API) for the treatment of atopic dermatitis, various types of dermatitis, skin wound, hemorrhoids and corneal epithelium disorder. In the present studies, the effects of sacran on skin injury and skin pain induced by stratum corneum tape-stripping and gastric ulcer induced by indomethacin, a non-steroidal anti-inflammatory drug (NSAID), and hydrochloride/ethanol (HCl/EtOH) in mice were investigated. Sacran solution 0.05% (w/v) showed greater reduction of skin injury and skin pain induced by stratum corneum tape-stripping, compared to that of 0.01% (w/v) and 0.1% (w/v) sacran solutions. In addition, the inhibitory effects of 0.05% (w/v) sacran on skin injury and skin pain induced by tape-stripping were significantly superior to 0.05% (w/v) hyaluronic acid solution. On the other hand, 1.0% (w/v) sacran solution significantly inhibited gastric ulcer formation induced by indomethacin, compared with 1% (w/v) dextran solution and the inhibitory effect of sacran was comparable to that of the positive control omeprazole. In addition, 1% (w/v) and 2% (w/v) sacran solution reduced HCl/EtOH-induced gastric ulcer in mice, with the alleviative effect of sacran was comparable to or greater than that of the positive control sodium alginate. These results suggest that sacran has potential as API to treat skin injury and pain induced by tape-stripping and gastric ulcer induced by NSAIDs and EtOH.


Assuntos
Cianobactérias/química , Polissacarídeos Bacterianos , Polissacarídeos , Dermatopatias/tratamento farmacológico , Úlcera Gástrica/tratamento farmacológico , Administração Oral , Administração Tópica , Animais , Anti-Inflamatórios não Esteroides , Modelos Animais de Doenças , Humanos , Camundongos , Dor/tratamento farmacológico , Dor/etiologia , Polissacarídeos/administração & dosagem , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos Bacterianos/administração & dosagem , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/uso terapêutico , Pele/lesões , Soluções
19.
Mater Sci Eng C Mater Biol Appl ; 99: 905-918, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889765

RESUMO

BACKGROUND: Due to unmet need for bone augmentation, our aim was to promote osteogenic differentiation of human adipose stem cells (hASCs) encapsulated in gellan gum (GG) or collagen type I (COL) hydrogels with bioactive glass (experimental glass 2-06 of composition [wt-%]: Na2O 12.1, K2O 14.0, CaO 19.8, P2O5 2.5, B2O3 1.6, SiO2 50.0) extract based osteogenic medium (BaG OM) for bone construct development. GG hydrogels were crosslinked with spermidine (GG-SPD) or BaG extract (GG-BaG). METHODS: Mechanical properties of cell-free GG-SPD, GG-BaG, and COL hydrogels were tested in osteogenic medium (OM) or BaG OM at 0, 14, and 21 d. Hydrogel embedded hASCs were cultured in OM or BaG OM for 3, 14, and 21 d, and analyzed for viability, cell number, osteogenic gene expression, osteocalcin production, and mineralization. Hydroxyapatite-stained GG-SPD samples were imaged with Optical Projection Tomography (OPT) and Selective Plane Illumination Microscopy (SPIM) in OM and BaG OM at 21 d. Furthermore, Raman spectroscopy was used to study the calcium phosphate (CaP) content of hASC-secreted ECM in GG-SPD, GG-BaG, and COL at 21 d in BaG OM. RESULTS: The results showed viable rounded cells in GG whereas hASCs were elongated in COL. Importantly, BaG OM induced significantly higher cell number and higher osteogenic gene expression in COL. In both hydrogels, BaG OM induced strong mineralization confirmed as CaP by Raman spectroscopy and significantly improved mechanical properties. GG-BaG hydrogels rescued hASC mineralization in OM. OPT and SPIM showed homogeneous 3D cell distribution with strong mineralization in BaG OM. Also, strong osteocalcin production was visible in COL. CONCLUSIONS: Overall, we showed efficacious osteogenesis of hASCs in 3D hydrogels with BaG OM with potential for bone-like grafts.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular , Colágeno Tipo I/farmacologia , Vidro/química , Osteogênese , Polissacarídeos Bacterianos/farmacologia , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Calcificação Fisiológica/efeitos dos fármacos , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Reagentes para Ligações Cruzadas/química , Durapatita/química , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Íons , Pessoa de Meia-Idade , Minerais/química , Osteocalcina/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Ratos , Soro/metabolismo , Análise Espectral Raman , Células-Tronco/efeitos dos fármacos , Tecidos Suporte/química
20.
Int J Biol Macromol ; 131: 10-18, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30851325

RESUMO

Marine bacteria secrete exopolysaccharides (EPS) with unique structural and functional properties and serve as a source of newer bioactive biopolymers. This study reports an EPS produced by a marine bacterium identified as Alteromonas sp. PRIM-28 for its bioactivities. The EPS was characterised using standard methods and tested for its bioactivities using in vitro models. EPS-A28 is an anionic heteropolysaccharide with a molecular weight of 780 kDa and exists as triple helical structure in aqueous solution. Monosaccharide composition is mannuronic acid, glucose and N-acetyl glucosamine repeating units in the ratio 1:3.67:0.93. The FT-IR spectra showed the presence of sulphate, phosphate and uronic acid residues. The thermal analysis showed partial degradation of the EPS-A28 at 190 °C and 40% of residues were stable up to 800 °C. It showed biocompatibility and induced proliferation and migration of dermal fibroblasts (HDF) and keratinocytes. EPS-A28 could increase the S-phase of cell cycle. The proliferative property of the EPS-A28 was established by the increased expression of fibroblast proliferation marker (Ki-67) also its capability of binding to cell surface. It also induced nitric oxide and arginase synthesis in macrophages. These findings suggest that EPS-A28 can be potentially used as a multifunctional bioactive polymer in wound care.


Assuntos
Alteromonas/química , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Biomarcadores , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibroblastos , Humanos , Queratinócitos , Camundongos , Peso Molecular , Monossacarídeos , Células RAW 264.7 , Termodinâmica
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