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1.
J Sci Food Agric ; 102(3): 1056-1065, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34312850

RESUMEN

BACKGROUND: Foam-gels are one of the most important multicomponent-model systems in aerated confectionery, and an investigation of their microstructure is desirable. In this research, the structure-function relationship of xanthan gum/guar gum (XG/GG) and licorice (Glycyrrhiza glabra) root extract powder (LEP) was investigated in a high-sugar medium. Foam-gel systems were prepared at 4:10% to 8:20% ratios of LEP to biopolymer. RESULTS: The results show that increasing the LEP content reduced both the melting point and enthalpy, probably due to higher overrun and weaker junctions. Boosting the XG/GG ratio led the enhancement of mechanical properties, whereas increasing the LEP concentration weakened all textural parameters, which could be due to the poor structure of the network in the presence of the foaming agent, increased moisture content and overrun. In the whipped mixture samples containing 10 g kg-1 XG/GG, higher foaming capacity was observed. By increasing the level of biopolymers, smaller and more uniform air cells were formed according to a scanning electron microscopical study. At higher concentration of LEP, smaller bubbles and increased porosity were seen, which could be attributed to the availability of surfactant in the interfacial layer. CONCLUSION: Maximum structural strength was achieved at a 4:20 ratio of LEP to XG/GG. In rheological experiments, pseudoplastic behavior was seen in all samples. Generally, this model system can be simulated for other herbal extracts containing natural surfactants such as saponins. Achieving a more detailed understanding of these structures and their interactions could help in formulating novel food products. © 2021 Society of Chemical Industry.


Asunto(s)
Galactanos/química , Glycyrrhiza/química , Mananos/química , Extractos Vegetales/química , Gomas de Plantas/química , Polisacáridos Bacterianos/química , Azúcares/química , Galactanos/aislamiento & purificación , Mananos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Gomas de Plantas/aislamiento & purificación , Raíces de Plantas/química , Polisacáridos Bacterianos/aislamiento & purificación , Reología , Azúcares/aislamiento & purificación , Tensoactivos/química , Tensoactivos/aislamiento & purificación , Viscosidad
2.
Int J Biol Macromol ; 174: 144-152, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33482213

RESUMEN

An exopolysaccharide (EPS) was purified from the probiotic bacterium Bacillus licheniformis AG-06 isolated from the polyherbal fermented traditional medicine (Ashwagandharishta) of Indian Ayurveda. High-performance liquid chromatography (HPLC) based compositional analysis exhibits the heteropolymeric nature of the EPS consisting of galactose, rhamnose, xylose, mannose, and glucose, as the monomeric units. Fourier-transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopic analyses confirm the presence of typical carbohydrate polymer functional groups and structural units, respectively. The purified EPS demonstrates the web-like fibrous and porous nature in scanning electron microscopic and atomic force microscopic studies. The purified EPS had shown 71.83% and 67.79% of flocculation and emulsification activities, respectively. Antioxidant activity was evaluated against 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), nitric oxide, and superoxide free radicals and the scavenging actions were increased in a dose-dependent manner. Moreover, the purified EPS exhibits a significant cytotoxic activity against the human lung carcinoma cells (A549), which strongly suggests the anticancer potential of the EPS derived from B. licheniformis AG-06.


Asunto(s)
Bacillus licheniformis/metabolismo , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/metabolismo , Células A549 , Antineoplásicos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión/métodos , Fermentación/fisiología , Radicales Libres , Humanos , Espectroscopía de Resonancia Magnética/métodos , Medicina Tradicional/métodos , Polisacáridos Bacterianos/aislamiento & purificación , Probióticos/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier/métodos
3.
Biomed Pharmacother ; 129: 110469, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32768956

RESUMEN

The infections caused by Herpes simplex viruses (HSV-1 and -2) are seriously endangering the health of all human beings. Once infected with these two viruses, it will cause life-long latency in the host, and the continuous recurrence of the infection will seriously affect the quality of life. Moreover, infections with HSV-1 and HSV-2 have been reported to make the body susceptible to other diseases, such as Alzheimer's disease and HIV. Thus, more attention should be paid to the development of novel anti-HSV drugs. Polysaccharides obtained from medicinal plants and microorganism (both land and sea) are reported to be promising anti-herpes substances. However, their antiviral mechanisms are complex and diverse, which includes direct inhibition of virus life cycle (Adsorption, penetration, genetic material and protein synthesis) and indirectly through improving the body's immunity. And each step of the research processes from extraction to structural analysis contributes to the result in terms of antiviral activity. Therefore, The complex mechanisms involved in the treatment of Herpes simplex infections makes development of new antiviral compounds is difficult. In this paper, the mechanisms of polysaccharides in the treatment of Herpes simplex infections, the research processes of polysaccharides and their potential clinical applications were reviewed.


Asunto(s)
Antivirales/farmacología , Polisacáridos Fúngicos/farmacología , Herpes Simple/tratamiento farmacológico , Herpesvirus Humano 1/efectos de los fármacos , Herpesvirus Humano 2/efectos de los fármacos , Extractos Vegetales/farmacología , Plantas Medicinales , Polisacáridos Bacterianos/farmacología , Polisacáridos/farmacología , Animales , Antivirales/aislamiento & purificación , Polisacáridos Fúngicos/aislamiento & purificación , Herpes Simple/virología , Herpesvirus Humano 1/crecimiento & desarrollo , Herpesvirus Humano 1/patogenicidad , Herpesvirus Humano 2/crecimiento & desarrollo , Herpesvirus Humano 2/patogenicidad , Humanos , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/química , Polisacáridos/aislamiento & purificación , Polisacáridos Bacterianos/aislamiento & purificación
4.
Probiotics Antimicrob Proteins ; 12(4): 1542-1554, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32279232

RESUMEN

Functional foods and nutraceuticals frequently contain viable probiotic strains that, at certain titers, are considered to be responsible of beneficial effects on health. Recently, it was observed that secreted metabolites might play a key role in this respect, especially in immunomodulation. Exopolysaccharides produced by probiotics, for example, are used in the food, pharmaceutical, and biomedical fields, due to their unique properties. Lactobacillus brevis CD2 demonstrated the ability to inhibit oral pathogens causing mucositis and periodontal inflammation and to reduce Helycobacter pylori infections. Due to the lack of literature, for this strain, on the development of fermentation processes that can increase the titer of viable cells and associated metabolites to industrially attractive levels, different batch and fed-batch strategies were investigated in the present study. In particular, aeration was shown to improve the growth rate and the yields of lactic acid and biomass in batch cultures. The use of an exponential feeding profile in fed-batch experiments allowed to produce 9.3 ± 0.45 × 109 CFU/mL in 42 h of growth, corresponding to a 20-fold increase of viable cells compared with that obtained in aerated batch processes; moreover, also increased titers of exopolysaccharides and lactic acid (260 and 150%, respectively) were observed. A purification process based on ultrafiltration, charcoal treatment, and solvent precipitation was applied to partially purify secreted metabolites and separate them into two molecular weight fractions (above and below 10 kDa). Both fractions inhibited growth of the known gut pathogen, Salmonella typhimurium, demonstrating that lactic acid plays a major role in pathogen growth inhibition, which is however further enhanced by the presence of Lact. brevis CD2 exopolysaccharides. Finally, the EPS produced from Lact. brevis CD2 was characterized by NMR for the first time up to date.


Asunto(s)
Medios de Cultivo/farmacología , Ácido Láctico/biosíntesis , Levilactobacillus brevis/metabolismo , Polisacáridos Bacterianos/biosíntesis , Probióticos/análisis , Técnicas de Cultivo Celular por Lotes/métodos , Fraccionamiento Químico/métodos , Medios de Cultivo/química , Suplementos Dietéticos , Fermentación , Alimentos Funcionales , Humanos , Concentración de Iones de Hidrógeno , Levilactobacillus brevis/efectos de los fármacos , Peso Molecular , Oxígeno/farmacología , Polisacáridos Bacterianos/aislamiento & purificación , Polisacáridos Bacterianos/farmacología , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/crecimiento & desarrollo
5.
Int J Biol Macromol ; 141: 809-821, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31499110

RESUMEN

In this study, the sulfated polysaccharide (SPs) was isolated from Spirulina platensis. The isolated SPs contains carbohydrate, sulfate, protein and uronic acid at 38.7 ±â€¯0.30%, 21.3 ±â€¯0.87%, 7.1 ±â€¯0.15% and 7.9 ±â€¯0.4% respectively. The elemental analysis confirmed the presence of carbon (18.01 ±â€¯0.10%), hydrogen (1.83 ±â€¯0.02%) and nitrogen (3.43 ±â€¯0.01%). The monosaccharide composition and molecular weight of SPs were analyzed by high-performance liquid chromatography and size exclusion chromatography respectively. The monosaccharide composition analysis showed the existence of glucose, rhamnose, xylose, fucose, mannose, galactose and the molecular weight of SPs was 1016 kDa. Further, the characterization of SPs was done by UV-visible spectroscopy, X-ray diffraction, FT-IR, 1H NMR and 13C NMR analysis. The obtained SPs exhibited potent antioxidant activity in DPPH (76.45 ±â€¯0.49%), reducing power (absorbance: 1.3 ±â€¯0.02), hydrogen peroxide scavenging (66.3 ±â€¯1.16%), hydroxyl scavenging (68.6 ±â€¯3.2%), nitric oxide (81.36 ±â€¯1.85%) and total antioxidant (absorbance:1.66 ±â€¯0.02) activities at 5 mg/ml. In addition, SPs revealed the highest antibacterial efficacy against the pathogenic bacteria Vibrio vulnificus in disc diffusion, agar bioassay and protein leakage assays at 100 µg/ml. Furthermore, the supplementation of 2% SPs through a feed to the Danio rerio fish enhances the growth and reproductive performances. This finding confirmed that the isolated SPs from S. platensis possess pharmaceutical as well as nutritional properties.


Asunto(s)
Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Spirulina/química , Sulfatos/química , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Peso Molecular , Polisacáridos Bacterianos/farmacología , Reproducción/efectos de los fármacos , Solubilidad , Análisis Espectral , Pez Cebra
6.
Int J Biol Macromol ; 128: 421-428, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30660569

RESUMEN

Based on the theory of extraction and diffusion of Chinese herbal medicine, the dynamic model of ultrasonic-assisted extraction process of polysaccharide from Nostoc commune Vauch. was established according to the second law of Fick, and further verified at different solid-liquid ratio (1/40-1/80 g/mL), temperature (313.15-353.15 K), ultrasonic power (240-600 W) and extraction time (0-25 min), the dynamic parameters including rate constant and relative extraction rate were respectively analyzed. The rate constant (k) gradually increased with the increase of temperature at different solid-liquid ratio. The maximum concentration of polysaccharide (NCVP) from N. commune was obtained with an optimal extraction condition at solid-liquid ratio of 1:50, extraction temperature of 353.15 K, ultrasonic power of 540 W and extraction time of 25 min. NCVP, the non reducing sugar with typical infrared spectrum characteristics of polysaccharide, dissolves in water but not dissolved in ethanol, acetone and petroleum ether and displays a good stability and smooth surface. The results provide the basis for NCVP in depth theoretical study of polysaccharide extraction processing.


Asunto(s)
Fraccionamiento Químico/métodos , Fenómenos Químicos , Modelos Teóricos , Nostoc commune/química , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Ondas Ultrasónicas , Cinética , Propiedades de Superficie , Termodinámica
7.
Mar Drugs ; 16(9)2018 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-30223612

RESUMEN

Many marine bacteria secrete exopolysaccharides (EPSs), which are made up of a substantial component of the macro-molecules surrounding cells. Recently, the wide demand for EPSs for food, cosmetics, pharmaceutical and other applications has led to great interest in them. In this study, an EPS produced by marine bacteria Aerococcus uriaeequi HZ strains (EPS-A) was isolated and purified to examine its structure and biological function. The molecular weight of EPS-A analyzed by high-performance liquid gel filtration chromatography (HPGFC) is found to have a number average of 2.22 × 105 and weight average of 2.84 × 105, respectively. High-performance liquid chromatography (HPLC) and Fourier-transform⁻infrared (FT⁻IR) analysis indicate that EPS-A was a polysaccharide composed of glucose and a little mannose. In addition, the flocculating rate of sewage of EPS-A was 79.90%. The hygroscopicity studies showed that hygroscopicity of EPS-A was higher than chitosan but lower than that of sodium hyaluronate. The moisture retention of EPS-A showed similar retention activity to both chitosan and sodium hyaluronate. EPS-A also can scavenge free radicals including both OH• free radical and O2•- free radical and the activity to O2•- free radical is similar to vitamin C. Safety assessment on mice indicated that the EPS-A is safe for external use and oral administration. EPS-A has great potential for applications in medicine due to its characteristics mentioned above.


Asunto(s)
Aerococcus/química , Organismos Acuáticos/química , Depuradores de Radicales Libres/farmacología , Polisacáridos Bacterianos/farmacología , Administración Oral , Animales , Cromatografía en Gel , Evaluación Preclínica de Medicamentos , Femenino , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Radicales Libres/metabolismo , Ratones , Peso Molecular , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de Fourier , Pruebas de Toxicidad Aguda
8.
Carbohydr Polym ; 181: 752-759, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29254032

RESUMEN

Green synthesis of silver nanoparticle (SNPs) has gained considerable attention in nano-biotechnology and nano-medicine owing their potency and eco-friendliness. In this, we account the exopolysaccharide and its mediated synthesis of SNPs and their biological activities. Exopolysaccharide of the Streptomyces violaceus composed of total carbohydrate (61.4%), ash (16.1%), moisture content (1.8%) and NMR confirmed their structural composition. SNPs synthesized by the exopolysaccharide, confirmed using UV-vis spectral analysis and characterized by TEM and XRD analyses. Further, the SNPs evaluated for its antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis using disc diffusion method. The SNPs has shown promising antibacterial activity were evaluated for MIC. Furthermore, the SNPs were tested for antioxidant activities and was found to have promising antioxidant activity over the standards. The above results prove that SNPs can be considered as a potent antibacterial and antioxidant drug in future.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Nanopartículas del Metal/uso terapéutico , Polisacáridos Bacterianos/química , Plata/química , Antibacterianos/síntesis química , Antioxidantes/síntesis química , Bacillus subtilis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Peróxido de Hidrógeno/química , Hierro/química , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Polisacáridos Bacterianos/aislamiento & purificación , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Streptomyces/química
9.
Int J Biol Macromol ; 94(Pt A): 187-193, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27720965

RESUMEN

This study evaluated five extracellular polymers of bacterial origin possessing mucoadhesive properties for their antimicrobial properties and toxicological characteristics. Of the five tested mucoadhesive biopolymers, the extracellular polymer produced by a strain of Acinetobacter haemolyticus exhibited broad antimicrobial efficacy towards Yersinia enterocolitica, Salmonella typhimurium, Listeria monocytogenes, Escherichia coli O157:H7 and Bacillus subtilis. Significant (p<0.05) inhibition of gram negative bacterial pathogens followed by gram positives were observed with the biopolymer at a dose of 40-60µg ml-1 at ambient temperature. The cytotoxicity under in vitro conditions and oral toxicity in murine models was also evaluated. The biopolymer did not elicit either haemolytic activity or toxicity in RAW 264.7 cell lines. Haemotological, histopathological and general examinations indicated no adverse effects in Swiss albino mice fed with the biopolymer (120mg kg-1 body weight-1 day1) over a period of 30 days. These results suggested that the biopolymer was well tolerated without any signs of toxicity and may have several potential biomedical applications where disinfection is desired.


Asunto(s)
Acinetobacter/química , Antibacterianos/farmacología , Polisacáridos Bacterianos/farmacología , Administración Oral , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibiosis , Pruebas Antimicrobianas de Difusión por Disco , Evaluación Preclínica de Medicamentos , Concentración 50 Inhibidora , Masculino , Ratones , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Células RAW 264.7
10.
Arch Pharm Res ; 39(9): 1223-31, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27357535

RESUMEN

Angiogenesis is an essential physiological step in wound healing and other regenerative processes. Here, we evaluated the angiogenic properties of an exopolysaccharide (EPS) secreted by MK1 (MK1-EPS), a novel bacterial strain isolated from Neungee mushrooms. MK1-EPS significantly increased human umbilical vein endothelial cell (HUVEC) proliferation, migration, and vascular tube formation. MK1-EPS enhanced the phosphorylation of extracellular signal-related kinase (ERK), c-Jun N-terminal kinase (JNK), and p38, which are mitogen-activated protein kinases. In addition, the expression of p21 and intercellular adhesion molecule 1 (ICAM1), and phosphorylation of signal transducer and activator of transcription 3 (STAT3), but not of protein kinase B (AKT), were increased. Specific inhibitors of p38 (SB203580), ERK (PD98059), and JNK (SP600125) inhibited MK1-EPS-induced HUVEC proliferation, tube formation, and cell migration, and partially attenuated MKI-EPS-induced expression of p21 and ICAM1, and STAT3 phosphorylation. After surgical implantation into rabbit calvarial bone defects, new blood vessel formation was significantly higher with MK1-EPS composite bone granules than with granules alone, and new bone formation increased significantly. Therefore, MK1-EPS induces angiogenesis and may have potential for use as a bone regeneration agent in bone tissue engineering applications.


Asunto(s)
Agaricales , Inductores de la Angiogénesis/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Polisacáridos Bacterianos/farmacología , Inductores de la Angiogénesis/aislamiento & purificación , Animales , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Polisacáridos Bacterianos/aislamiento & purificación , Conejos
11.
Carbohydr Polym ; 144: 205-14, 2016 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-27083810

RESUMEN

The exopolysaccharides (EPS) produced by Se-enriched Lactobacillus plantarum BC-25 was purified to illustrate its structure and conformational characterization. The yield of EPS (324.80mg/l) was obtained with a sodium selenite concentration of 6µg/ml. The results indicated that the EPS was soluble in water, but insoluble in organic solvents. The molecular weight of this highly thermal stability EPS was 1.83×10(4)Da and 1.33×10(4)Da with or without Se enriched respectively. The EPS was composed of mannose, galactose and glucose in a molar ratio of 92.21:1.79:6.00 and 91.36:2.44:6.20 with or without Se. This compound had a backbone of (1→2)-linked Man, (1→2.6)-linked Glc, (2→6)-linked Man, and (2→6)-linkedGal confirmed by GC-MS. IR analysis suggested that the EPS belonged to heteropolysaccharide with a pyran group, with possible presence of SeO and CSeC residues that Se may substitutes CH3 in -OCH3 in the polysaccharide as confirmed by NMR spectroscopy.


Asunto(s)
Lactobacillus plantarum/química , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Secuencia de Carbohidratos , Lactobacillus plantarum/metabolismo , Monosacáridos/análisis , Polisacáridos Bacterianos/biosíntesis , Selenio/química
12.
Molecules ; 21(2)2016 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-26861269

RESUMEN

An endophytic bacterium was isolated from the Chinese medicinal plant Artemisia annua L. The phylogenetic and physiological characterization indicated that the isolate, strain SZ-1, was Bacillus cereus. The endophyte could produce an exopolysaccharide (EPS) at 46 mg/L. The 1,1-diphenyl-2-picrylhydracyl (DPPH) radical scavenging activity of the EPS reached more than 50% at 3-5 mg/mL. The EPS was also effective in scavenging superoxide radical in a concentration dependent fashion with an EC50 value of 2.6 mg/mL. The corresponding EC50 for scavenging hydroxyl radical was 3.1 mg/mL. Moreover, phenanthroline-copper complex-mediated chemiluminescent emission of DNA damage was both inhibited and delayed by EPS. The EPS at 0.7-1.7 mg/mL also protected supercoiled DNA strands in plasmid pBR322 against scission induced by Fenton-mediated hydroxyl radical. The preincubation of PC12 cells with the EPS prior to H2O2 exposure increased the cell survival and glutathione (GSH) level and catalase (CAT) activities, and decreased the level of malondialdehyde (MDA) and lactate dehydrogenase (LDH) activity in a dose-dependent manner, suggesting a pronounced protective effect against H2O2-induced cytotoxicity. Our study indicated that the EPS could be useful for preventing oxidative DNA damage and cellular oxidation in pharmaceutical and food industries.


Asunto(s)
Bacillus cereus/química , Depuradores de Radicales Libres/farmacología , Polisacáridos Bacterianos/farmacología , Animales , Bacillus cereus/genética , Compuestos de Bifenilo/química , Daño del ADN , Evaluación Preclínica de Medicamentos , Endófitos/química , Endófitos/genética , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Peróxido de Hidrógeno/farmacología , Tipificación Molecular , Oxidantes/farmacología , Oxidación-Reducción , Estrés Oxidativo , Células PC12 , Filogenia , Picratos/química , Plásmidos/química , Plásmidos/genética , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Ratas , Superóxidos/química
13.
Carbohydr Polym ; 116: 67-73, 2015 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-25458274

RESUMEN

Haemophilus influenzae type b (Hib) is a human pathogen that causes meningitis in infants worldwide. Capsular polysaccharide linked to a protein has been used as an efficient vaccine, and this approach has reduced the incidence of Hib disease since its inclusion in national immunisation campaigns. The traditional polysaccharide downstream process is based on several ethanol precipitations, treatment with detergents and centrifugation. The aim of this study was to introduce tangential microfiltration (TMF) in the place of centrifugation to simplify handling and to scale up the process. The purity of the polysaccharide was RPNA=1747.2 and RPPrt=196.1 for nucleic acid and protein, respectively, meeting the quality requirements for this polysaccharide. Moreover, the polysaccharide was recognised by at specific antibody, and the ribose and phosphate contents were within the expected limits. Thus, we established a process for the purification of capsular polysaccharide produced by H. influenzae type b that is effective, robust and feasible to be scaling up.


Asunto(s)
Haemophilus influenzae tipo b , Polisacáridos Bacterianos/aislamiento & purificación , Proteínas Bacterianas/análisis , Reactores Biológicos , Precipitación Química , Filtración , Haemophilus influenzae tipo b/metabolismo , Ácidos Nucleicos/análisis , Fósforo/análisis , Polisacáridos Bacterianos/metabolismo
14.
Acta Sci Pol Technol Aliment ; 14(3): 247-255, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-28068032

RESUMEN

BACKGROUND: The ability of lactobacilli to adhere to the surface of the intestine is an important functional characteristic which can largely determine the effective colonization of the intestinal tract by probiotics. The following study compares the adhesion efficiency of the twenty strains of Lactobacillus genus belonging to Casei group to the Caco-2 cells and gastrointestinal mucus. METHODS: Twenty isolates of lactobacilli belonging to Casei group were tested. The ability of bacterial cells to adhere to mucus was examined using adhesion assay to gastrointestinal mucus. Obtained results were compared with adhesion efficiency to Caco-2 cells. Phylogenetic relationship between isolates was analysed by rep-PCR. RESULTS: The results showed large differences in adhesion efficiency between strains, as well as differences in the efficiency of adhesion to the intestinal epithelial cells and mucus. Group similarity highlighted by a rep-PCR technique does not correspond with groups of similarity in terms of the characteristics of the ability to adhere to mucus or the epithelial cells of intestinal tract. CONCLUSIONS: Strains having a high adhesion efficiency to enterocytes do not always show a high adhesion efficiency to the mucus. This may indicate the presence of different and multiple factors responsible for adhesion efficiency of Lactobacillus group Casei strains to epithelial cells and mucus.


Asunto(s)
Enterocitos/microbiología , Lacticaseibacillus casei/fisiología , Moco/microbiología , Probióticos , Adhesión Bacteriana , Células CACO-2 , Suplementos Dietéticos/microbiología , Heces/microbiología , Humanos , Mucosa Intestinal/microbiología , Lacticaseibacillus casei/clasificación , Lacticaseibacillus casei/genética , Lacticaseibacillus casei/aislamiento & purificación , Tipificación Molecular , Filogenia , Polonia , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Probióticos/clasificación , Especificidad de la Especie
15.
Carbohydr Polym ; 114: 48-56, 2014 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-25263863

RESUMEN

Mixtures of gellan gum (GL) and a xyloglucan (XGJ) extracted from Hymenaea courbaril seeds were prepared in a solution of 0.15 mol L(-1) NaCl. Rheology measurements revealed that 2.4 g L(-1) pure GL formed a brittle hydrogel, and GL-XGJ blends showed improved pseudoplastic character with higher XGJ contents. SAXS analyses showed that the Rg dimensions ranged from 1.3 to 4.9 nm, with larger values occurring as the amount of XGJ increased, and diffusion tests indicated that better diffusion of methylene blue dye was obtained in the network with a higher XGJ content. AFM topographic images of the films deposited onto mica revealed fewer heterogeneous surfaces with increased XGJ contents. The water contact angle revealed more hydrophobic character on all of the films, and the wettability decreased with increasing amounts of XGJ. Therefore, the demonstrated benefit of using XGJ blends is the production of a soft material with improved interface properties.


Asunto(s)
Glucanos/aislamiento & purificación , Hidrogeles/aislamiento & purificación , Nanotecnología/métodos , Polisacáridos Bacterianos/aislamiento & purificación , Xilanos/aislamiento & purificación , Glucanos/química , Hidrogeles/química , Hymenaea , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Polisacáridos Bacterianos/química , Difracción de Rayos X , Xilanos/química
16.
Carbohydr Polym ; 112: 615-21, 2014 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-25129790

RESUMEN

The crude exopolysaccharides (EPSs) were obtained from Arthrobacter ps-5 fermentation using various carbohydrate sources followed by centrifugation, ethanol precipitation, and the isolated EPSs were further deproteinized and lyophilized. Carbohydrates from various sources resulted in different yield of EPSs from the fermentation and different molecular weight of EPSs. A maximum yield of 0.27 mg/g was achieved by using the culture medium supplemented with sucrose. The EPS produced by glucose-supplemented medium had the maximum content of acidic polysaccharides, subsequently presented the highest biosorption capacity for Cu(2+) and Pb(2+) at 257.9 mg/g and 331.8 mg/g, respectively. The ratio of acidic to neutral polysaccharides presented in EPSs was a key factor to explicate the biosorption mechanism, the higher the ratio, the stronger the biosorption capacity.


Asunto(s)
Arthrobacter/metabolismo , Polisacáridos Bacterianos/química , Adsorción , Carbono/metabolismo , Cobre/química , Medios de Cultivo/química , Fermentación , Plomo/química , Metales/química , Peso Molecular , Monosacáridos/análisis , Polisacáridos Bacterianos/aislamiento & purificación , Polisacáridos Bacterianos/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Sacarosa/metabolismo
17.
Enzyme Microb Technol ; 55: 113-20, 2014 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-24411453

RESUMEN

In an ongoing survey for bioactive potential of microorganisms from different biosphere zones of India, a promising Kocuria rosea strain BS-1 was identified which produced an exopolysaccharide (designated as Kocuran) exhibiting in vitro antioxidant and immunosuppression properties. Kocuran was characterized as a heteropolysaccharide with repeating monosaccharide residues of glucose, galactose, mannose and glucuronic acid with an average molecular mass of 51.2 kDa. In RAW 264.7 macrophages, Kocuran significantly downregulated the LPS-stimulated ROS, NO, TNF-α, IL-6 and C3 complement component secretion to 4.71±0.08%, 4.11±0.06%, 11.19±0.06 pg ml⁻¹, 9.12±0.07 pg ml⁻¹ and 20.81±0.06 ng/106 cells ml⁻¹, respectively. Furthermore, it inhibited the PHA-stimulated proliferation of human peripheral blood mononuclear cells with IC50 of 100.13±2.1 µg ml⁻¹. In addition, the classical and alternative pathway mediated hemolysis was also inhibited with CH50 and AH50 of 100.96±1.75 and 98.60±1.93 µg ml⁻¹, respectively. Kocuran did not inhibit the LPS-induced LAL enzyme and the binding of FITC-LPS to macrophages suggesting that Kocuran does not neutralize the LPS activity. These results demonstrate the in vitro suppression of activation and macrophage-derived inflammatory cytokines and complement mediated hemolysis indicating its in vitro immunosuppression activity.


Asunto(s)
Antioxidantes/aislamiento & purificación , Inmunosupresores/aislamiento & purificación , Micrococcaceae/química , Polisacáridos Bacterianos/aislamiento & purificación , Animales , Antioxidantes/química , Antioxidantes/farmacología , Secuencia de Carbohidratos , Línea Celular , Activación de Complemento/efectos de los fármacos , Inactivadores del Complemento/aislamiento & purificación , Inactivadores del Complemento/farmacología , Proteínas del Sistema Complemento/efectos de los fármacos , Citocinas/metabolismo , Evaluación Preclínica de Medicamentos , Hemólisis/efectos de los fármacos , Humanos , Inmunosupresores/química , Inmunosupresores/farmacología , Concentración 50 Inhibidora , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Lipopolisacáridos/farmacología , Activación de Linfocitos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Datos de Secuencia Molecular , Peso Molecular , Monosacáridos/análisis , Óxido Nítrico/biosíntesis , Fitohemaglutininas/farmacología , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/farmacología , Especies Reactivas de Oxígeno/metabolismo
18.
Arch Oral Biol ; 58(12): 1804-11, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24200307

RESUMEN

OBJECTIVE: Oral ailments are often treated with antibiotics, which are rendered ineffective as bacteria continue to develop resistance against them. It has been suggested that the nanoparticles (NPs) approach may provide a safer and viable alternative to traditional antibacterial agents. Therefore, nickel (Ni)- and nickel oxide (NiO)-NPs were synthesized, characterized and assessed for their efficacy in reducing oral bacterial load in vitro. Also, the effects of bulk compound NiCl2 (Ni ions), along with the Ni- and NiO-NPs on bacterial exopolysaccharide (EPS) production and biofilm formation on the surface of artificial teeth, and acrylic dentures, were investigated. METHODS: Total bacteria from a healthy male were collected and adjusted to 4×109cells/ml for all the tests. Effect of the NPs on growth, biofilm formation, EPS production and acid production from glucose was tested using standard protocols. RESULTS: Data revealed that the Ni-NPs (average size 41.23nm) exhibited an IC50 value of 73.37µg/ml against total oral bacteria. While, NiO-NPs (average size 35.67nm) were found less effective with much higher IC50 value of 197.18µg/ml. Indeed, the Ni ions exhibited greater biocidal activity with an IC50 value of 70µg/ml. Similar results were obtained with biofilm inhibition on the surfaces of dental prostheses. The results explicitly suggested the effectiveness of tested Ni compounds on the growth of oral bacteria and biofilm formation in the order as NiCl2>Ni-NPs>NiO-NPs. CONCLUSION: The results elucidated that Ni-NPs could serve as effective nanoantibiotics against oral bacteria.


Asunto(s)
Antibacterianos/uso terapéutico , Biopelículas/efectos de los fármacos , Prótesis Dental/microbiología , Boca/microbiología , Nanopartículas/uso terapéutico , Níquel/uso terapéutico , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Antibacterianos/química , Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Boca/efectos de los fármacos , Nanopartículas/química , Níquel/farmacología , Polisacáridos Bacterianos/aislamiento & purificación , Difracción de Rayos X
19.
J Sci Food Agric ; 91(12): 2284-91, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21560134

RESUMEN

BACKGROUND: Immunomodulation by probiotic microorganisms has become a topic of increasing interest in food microbiology. Polysaccharides are broadly used in the food industry as gelling, thickening, stabilizing, or emulsifying agents. Some probiotics such as lactic acid bacteria also produce exopolysaccharides that stimulate macrophage production of cytokines. The aim of this study was to characterize the effects of exopolysaccharides of Lactobacillus paracasei subsp. paracasei NTU 101 (101EP) and Lactobacillus plantarum NTU 102 (102EP) exopolysaccharides on antioxidant activity and immunomodulation in vitro. RESULTS: The sugar composition (including arabinose, galactose, glucose, fructose, mannose, and maltose) of 101EP and 102EP was quantified by high-performance anion-exchange chromatography. Cytokine production (including IL-6, TNF-α, and IL-1ß) was induced by 101EP and 102EP in Raw 264.7 in a dose-dependent manner (5-500 µg mL(-1) ). 101EP and 102EP also demonstrated potential antioxidant properties (1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, chelation of ferrous ions, inhibition of linoleic acid peroxidation, and reducing power) in vitro. CONCLUSION: 101EP and 102EP stimulate cell proliferation and may be useful as a mild immune modulator of macrophages.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Antioxidantes/farmacología , Lactobacillus/metabolismo , Polisacáridos Bacterianos/farmacología , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/aislamiento & purificación , Adyuvantes Inmunológicos/metabolismo , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/metabolismo , Línea Celular Transformada , Proliferación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Citocinas/metabolismo , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/metabolismo , Depuradores de Radicales Libres/farmacología , Quelantes del Hierro/química , Quelantes del Hierro/aislamiento & purificación , Quelantes del Hierro/metabolismo , Quelantes del Hierro/farmacología , Lactobacillus/inmunología , Lactobacillus plantarum/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Maltosa/análisis , Ratones , Monosacáridos/análisis , Oxidación-Reducción/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Polisacáridos Bacterianos/metabolismo , Probióticos/metabolismo , Especificidad de la Especie , Propiedades de Superficie
20.
Pharm Biol ; 49(3): 319-26, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21323484

RESUMEN

CONTEXT: Previously, we showed the essential oils (EO) of the mountain celery [Cryptotaenia japonica Hass (Umbelliferae)] seeds (MCS) to be a prominent hypolipidemic agent. OBJECTIVE: We hypothesized the aqueous extract (AE) of its seeds could also exhibit a comparable nutritional effect. MATERIALS AND METHODS: Experiments were carried out for compositional analysis, antioxidant assay, and hypolipidaemic assay with AE in hamsters. RESULTS: AE contained soluble arabinogalactan (AGal) with molecular weight (MW) 878 kDa. AE also was enriched in polyphenolics and flavonoids, reaching 30.4 and 2.20 mg/100 g, respectively. AGal consisted of eight monosaccharides (in mols %), galactose (28.75), arabinose (24.84), glucose (17.91), mannose (6.93), ribose (6.03), fucose (5.83), xylose (5.30), and rhamnose (4.41), with average MW 878 kDa. In vitro, AE showed potent ferrous chelating and DPPH scavenging effects but only moderate H2O2 scavenging capability. In hamsters, AE exhibited promising hypolipidemic bioactivity, in particular, the HDL-C and hepatic unsaturated fatty acid (UFA) biosynthesis regarding oleic, linoleic, and arachidonic acids. DISCUSSION AND CONCLUSION: The presence of AGal enhanced the hypolipidemic and antioxidative bioactivity of MCS. MCS is feasibly beneficial to the hepatic de novo UFA synthesis and the hypolipidemics as evidenced by hamster model.


Asunto(s)
Apium , Galactanos/aislamiento & purificación , Hipolipemiantes/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Polifenoles/aislamiento & purificación , Polisacáridos Bacterianos/aislamiento & purificación , Semillas , Animales , Cricetinae , Sinergismo Farmacológico , Ácidos Grasos/metabolismo , Galactanos/metabolismo , Hipolipemiantes/metabolismo , Masculino , Mesocricetus , Extractos Vegetales/metabolismo , Polifenoles/metabolismo , Polisacáridos Bacterianos/metabolismo , Distribución Aleatoria
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