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1.
3 Biotech ; 6(1): 70, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28330139

RESUMEN

Water hyacinth (Eichhornia crassipes) represents a promising candidate for fuel ethanol production in tropical countries because of their high availability and high biomass yield. Bioconversion of such biomass to bioethanol could be wisely managed through proper technological approach. In this work, pretreatment of water hyacinth (10 %, w/v) with dilute sulfuric acid (2 %, v/v) at high temperature and pressure was integrated in the simulation and economic assessment of the process for further enzymatic saccharification was studied. The maximum sugar yield (425.6 mg/g) through enzymatic saccharification was greatly influenced by the solid content (5 %), cellulase load (30 FPU), incubation time (24 h), temperature (50 °C), and pH (5.5) of the saccharifying medium. Central composite design optimized an ethanol production of 13.6 mg/ml though a mixed fermentation by Saccharomyces cerevisiae (MTCC 173) and Zymomonas mobilis (MTCC 2428). Thus the experiment imparts an economic value to water hyacinths that are cleared from choking waterways.

2.
Appl Biochem Biotechnol ; 175(7): 3371-86, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25649444

RESUMEN

This study aimed to explore the bactericidal activity of a feather-degraded active peptide against multiple-antibiotic-resistant (MAR) Staphylococcus aureus. An antibacterial peptide (ABP) was isolated from the chicken feathers containing fermented media of Paenibacillus woosongensis TKB2, a keratinolytic soil isolate. It was purified by HPLC, and its mass was found to be 4666.87 Da using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) spectroscopy. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of this peptide were 22.5 and 90 µg/ml, respectively. SEM study revealed the distorted cell wall of the test strain along with pore formation. The possible reason for bactericidal activity of the peptide is due to generation of reactive oxygen species (ROS), resulting in membrane damage and leakage of intracellular protein. Complete sequence of the peptide was predicted and retrieved from the sequence database of chicken feather keratin after in silico trypsin digestion using ExPASy tools. Further, net charge, hydrophobicity (77.7 %) and molecular modelling of the peptide were evaluated for better understanding of its mode of action. The hydrophobic region (17 to 27) of the peptide may facilitate for initial attachment on the bacterial membrane. The ABP exhibited no adverse effects on RBC membrane and HT-29 human cell line. This cytosafe peptide can be exploited as an effective therapeutic agent to combat Staphylococcal infections.


Asunto(s)
Farmacorresistencia Bacteriana/inmunología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Péptidos/administración & dosificación , Infecciones Estafilocócicas/inmunología , Animales , Pollos/inmunología , Cromatografía Líquida de Alta Presión , Plumas/química , Plumas/inmunología , Humanos , Staphylococcus aureus Resistente a Meticilina/inmunología , Pruebas de Sensibilidad Microbiana , Péptidos/inmunología , Péptidos/aislamiento & purificación , Infecciones Estafilocócicas/prevención & control
4.
Clin Exp Nephrol ; 19(2): 168-77, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24740592

RESUMEN

BACKGROUND: Currently kidney disease appears a foremost problem across the world. Acetaminophen is a commonly used antipyretic agent, which in high doses, causes uremia and used for experimentally induction of kidney disease. Bacteriotherapy affords a promising approach to mitigate uremic toxins by ingestion of urease positive bacteria, probiotics and symbiotic able to catabolize uremic solutes within the gut. The present study evaluates the effect of seven commercial symbiotic on kidney disease. METHODS: Fifty-four albino male rats were randomly divided into nine groups. Control group (Group-I) received distilled water interperitoneally for 7 days. Positive control group (Group-II) received 500 mg/kg acetaminophen interperitoneally for 7 days. Commercially available seven symbiotic combinations at a dose of 10(9)cells/day for 3 weeks was administered to the tested groups (Group III-IX) after receiving 500 mg/kg/day acetaminophen interperitoneally for 7 days. Blood, kidney, liver and stool samples were collected after scarification for biochemical tests and DNA fragmentation assay of kidney tissue, kidney histological studies. Limited fecal analysis was conducted. RESULT: Blood urea nitrogen and toxicity indicators were increased, and antioxidant enzymes were decreased in Group-II. Blood urea nitrogen, toxicity indicators, glomerular necrosis, DNA damage of kidney tissue were reduced, and antioxidant enzymes were increased significantly in the treated Groups IV and IX (p < 0.05) in response to Group-II. Number of pathogenic bacteria decreased in synbiotic treated groups than Group I and II. CONCLUSION: The study demonstrated that some of commercial symbiotic combination can reduce the sever effect of kidney disease.


Asunto(s)
Heces/microbiología , Glomérulos Renales/patología , Simbióticos/administración & dosificación , Uremia/tratamiento farmacológico , Uremia/patología , Acetaminofén , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Nitrógeno de la Urea Sanguínea , Catalasa/metabolismo , Creatinina/sangre , Fragmentación del ADN , Glutatión/metabolismo , Glomérulos Renales/metabolismo , Masculino , Malondialdehído/metabolismo , Necrosis/patología , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo , Urea/sangre , Uremia/sangre , Uremia/inducido químicamente
5.
Food Chem ; 158: 325-34, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-24731350

RESUMEN

Chitosaccharides (CS) of varied size were prepared from shrimp shell through sequential catalysis, using crude protease and chitinase enzymes immobilized on agar beads. In the optimized state, immobilization yield and activity yield for protease were 84% and 62%, and for chitinase were 75% and 57%, respectively. Immobilized protease and chitinase treatment improved CS yields (101 µg/ml) and retained 63% and 52% of activities after 10 reuses, respectively. Stronger radical-scavenging activity (RSA) of CS against ABTS, DPPH and hydroxyl radical was noted with EC50 values 19.1, 26.4 and 29.6 µg/ml, respectively. Peroxyl and superoxide RSAs of 96.8% and 88.6% were noticed at 70 µg/ml of CS. Singlet oxygen quenching, reducing power and ferrous ion-chelating activities of CS were also pronounced. CS reasonably reduced oxidative damage of DNA, protein and RBC by inhibiting H2O2 and AAPH radicals. Reversible CS-DNA condensation leads to DNA stabilization without changing its conformation and advocates its employment in gene therapy.


Asunto(s)
Antioxidantes/química , Quitosano/química , ADN/química , Péptido Hidrolasas/química , Residuos/análisis , Antioxidantes/farmacología , Quelantes/química , Quelantes/farmacología , Quitinasas/química , Quitosano/farmacología , Enzimas Inmovilizadas/química , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Radical Hidroxilo/química , Oxidación-Reducción
6.
Bioresour Technol ; 157: 327-40, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24613317

RESUMEN

Tannin-rich materials are abundantly generated as wastes from several agroindustrial activities. Therefore, tannase is an interesting hydrolase, for bioconversion of tannin-rich materials into value added products by catalyzing the hydrolysis of ester and depside bonds and unlocked a new prospect in different industrial sectors like food, beverages, pharmaceuticals, etc. Microorganisms, particularly bacteria are one of the major sources of tannase. In the last decade, cloning and heterologous expression of novel tannase genes and structural study has gained momentum. In this article, we have emphasized critically on bacterial tannase that have gained worldwide research interest for their diverse properties. The present paper delineate the developments that have taken place in understanding the role of tannase action, microbial sources, various cultivation aspects, downstream processing, salient biochemical properties, structure and active sites, immobilization, efforts in cloning and overexpression and with special emphasis on recent molecular and biotechnological achievements.


Asunto(s)
Bacterias/enzimología , Biotecnología/métodos , Hidrolasas de Éster Carboxílico/metabolismo , Fermentación , Taninos/química , Taninos/metabolismo
7.
J Biosci Bioeng ; 117(2): 170-177, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23994224

RESUMEN

Production and optimization of ß-N-acetyl glucosaminidase and chitinase by Ca-alginate immobilized Aeromonas hydrophila SBK1 was carried out using prawn shell as cost-effective substrate. Beads prepared with 5.0% Na-alginate (containing 2.0% colloidal chitin) and 1.0 M CaCl2 showed considerable beads integrity and supported maximum production of chitinolytic enzymes. Bead diameter, 3 mm; temperature, 35°C; pH 7.0; agitation, 90 rpm were found ideal for the maximum production of the enzymes. The fermentation and thermodynamic indices revealed the feasibility of immobilized cells over free cells for enzymes production. Reasonable amount of chitosaccharides (degree of polymerization; 1-6) accumulated in the production media which have paramount antioxidant activity. Scale up experiment was successfully carried out in 5 L fermentor. In immobilized state, the chitosaccharides yield and antioxidant activity increased about 44.76% and 22.22%, whereas specific productivity of ß-N-acetyl glucosaminidase and chitinase increased by 22.86% and 33.37% over free state. The cell entrapped beads can be reused upto ten cycles without marked loss of its biocatalytic efficiency. High level of protoplast of Aspergillus niger was generated by treating mycelia with 10 U/ml of crude chitinase after 4 h at pH 7.0 and in the temperature 35-40°C, and 67% of the protoplasts were found to be regenerated.


Asunto(s)
Aeromonas hydrophila/metabolismo , Exoesqueleto/metabolismo , Aspergillus niger/citología , Quitinasas/biosíntesis , Quitinasas/metabolismo , Protoplastos/metabolismo , Acetilglucosaminidasa/biosíntesis , Acetilglucosaminidasa/metabolismo , Alginatos/metabolismo , Alginatos/farmacología , Exoesqueleto/química , Animales , Reactores Biológicos , Cloruro de Calcio/metabolismo , Cloruro de Calcio/farmacología , Células Inmovilizadas/metabolismo , Quitina/metabolismo , Fermentación , Ácido Glucurónico/metabolismo , Ácido Glucurónico/farmacología , Ácidos Hexurónicos/metabolismo , Ácidos Hexurónicos/farmacología , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Tamaño de la Partícula , Penaeidae , Temperatura
8.
J Basic Microbiol ; 54 Suppl 1: S142-51, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23832828

RESUMEN

An endoglucanase from Aspergillus fumigatus ABK9 was purified from the culture extract of solid-state fermentation and its some characteristics were evaluated. The molecular weight of the purified enzyme (56.3 kDa) was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, zymogram analysis and confirmed by MALDI-TOF mass spectrometry. The enzyme was active optimally at 50 °C, pH 5.0 and stable over a broad range of pH (4.0-7.0) and NaCl concentration of 0-3.0 M. The pKa1 and pKa2 of the ionizable groups of the active sites were 2.94 and 6.53, respectively. The apparent Km , Vmax , and Kcat values for carboxymethyl cellulose were 6.7 mg ml(-1), 775.4 µmol min(-1) , and 42.84 × 10(4) s(-1), respectively. Thermostability of the enzyme was evidenced by the high activation energy (91.45 kJ mol(-1)), large enthalpy for activation of denaturation (88.77 kJ mol(-1)), longer half-life (T1/2) (433 min at 50 °C), higher melting temperature (Tm ) (73.5 °C), and Q10 (1.3) values. All the characteristics favors its suitability as halotolerant and thermostable enzyme during bioprocessing of lignocellulosic materials.


Asunto(s)
Aspergillus fumigatus/enzimología , Celulasa/química , Celulasa/metabolismo , Carboximetilcelulosa de Sodio/metabolismo , Celulasa/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Cinética , Peso Molecular , Cloruro de Sodio/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Temperatura
9.
Indian J Exp Biol ; 51(2): 174-80, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23923611

RESUMEN

The total antioxidative activity of L. ingluviei ADK10 isolated from chicken intestine intact cells and cell free culture supernatant (CFCS) was 54- 67.95%. The ability to scavenge a,a-Diphenyl-b-Picrylhydrazyl free radical ranged from 71 and 64% in intact cells and CFCS respectively. Total reducing activity of bacteria was equivalent to 290 microM/L of cysteine. Reducing glutathione activity was equivalent to 93.95 microg/mL. Oral administration of the strain at a dose of 10(9) cfu/kg body weight to acetaminophen induced oxidative stress in rats increased catalase, glutathione and superoxide dismutase activity in the blood, liver and kidney and lowered malondialdehyde level. The results indicate that L. ingluviei ADK10 has potential free radical scavenging activity for the treatment of oxidative stress related disease.


Asunto(s)
Pollos/microbiología , Intestinos/microbiología , Lactobacillus/aislamiento & purificación , Lactobacillus/metabolismo , Estrés Oxidativo , Acetaminofén , Animales , Antioxidantes/metabolismo , Catalasa/sangre , Glutatión/sangre , Riñón/enzimología , Lactobacillus/clasificación , Hígado/enzimología , Hígado/patología , Masculino , Malondialdehído/sangre , Datos de Secuencia Molecular , Oxidación-Reducción , Filogenia , Ratas , Ratas Wistar , Superóxido Dismutasa/sangre
10.
Pol J Microbiol ; 62(1): 31-43, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23829075

RESUMEN

This study was aimed to evaluate the pattern of cellulase biosynthesis from Aspergillusfumigatus ABK9 under submerged fermentation. Production was increased concomitantly with fungal growth up to 72 h and reached maximum (Xmax -6.72 g/l) with specific growth rate (mu max) of 0.126/h. Highest specific rate of enzyme production (q ) was found at initial medium pH of 5.0 and incubation temperature of 30 degrees C. At the same time, in the presence of 2-deoxy-D-glucose concentration of 0.5 mg/ml, the production of cellulolytic enzymes, viz, carboxymethyl cellulase activity (CMCase), filter paper degrading activity (FPase) and P-glucosidase activity reached maximum of 132.2, 21.3 and 28.9 U/ml, respectively. Cellulase biosynthesis was induced in respect to higher volumetric production rate (Qp), specific rate of enzymes production (qp, U/g biomass/h) and enzyme/biomass yield (YE/X) when grown in carboxymethyl cellulose in comparison to other saccharides as sole carbon source. Induction ratios (IR) of cellulases were between 12.3 and 24.4 in the presence of 1.5% (w/v) CMC in the culture media. The strain was quite resistant to catabolic repression by glucose up to 0.4% (w/v). Cellulases production was greatly influenced in the presence of yeast extract and potassium dihydrogen phosphate (KH2POA) as nitrogen and phosphate sources in the culture media. C/N ratio of 10.0 and C/P ratio of 4.0 proved to be the best for the production of enzyme cocktail. Along with the high production yield, the crude enzymes showed a promising cellulose hydrolyzing efficiency of rice straw, indicating the enzyme could be beneficial for its large scale industrial exploitation.


Asunto(s)
Aspergillus fumigatus/clasificación , Aspergillus fumigatus/enzimología , Celulasa/metabolismo , Celulosa/metabolismo , Aspergillus fumigatus/genética , Aspergillus fumigatus/metabolismo , Carbono , Celulasa/genética , Desoxiglucosa , Fermentación , Regulación Enzimológica de la Expresión Génica , Regulación Fúngica de la Expresión Génica/fisiología , Concentración de Iones de Hidrógeno , Nitrógeno , Oryza , Fósforo , Filogenia , Tallos de la Planta/metabolismo , Temperatura
11.
Bioresour Technol ; 128: 290-6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23196251

RESUMEN

Response surface methodology was employed to optimize mixed substrate solid state fermentation for the production of cellulases and xylanase by Aspergillus fumigatus ABK9. Among 11 different parameters, fermentation time (86-88 h), medium pH (6.1-6.2), substrate amount (10.0-10.5 g) and substrate ratio (wheat bran:rice straw) (1.1) had significantly influences on enzyme production. Under these conditions endoglucanase, ß-glucosidase, FPase (filter paper degrading activity) and xylanase activities of 826.2, 255.16, 102.5 and 1130.4 U/g, respectively were obtained. The enzyme cocktail extracted (solid to water ratio of 1:10) from the ferments increased brightness of waste office paper pulp by 82.8% ISO, Ink(D) value by 82.1%, removed chromophores (2.53 OD; A(237)nm) and hydrophobic compounds (1.15 OD; A(465)nm) and also decreased the kappa number to 13.5 from 16.8.


Asunto(s)
Aspergillus fumigatus/enzimología , Celulasa/biosíntesis , Celulasa/química , Tinta , Oryza/microbiología , Papel , Triticum/microbiología , Celulosa/química , Residuos Industriales/prevención & control
12.
Indian J Exp Biol ; 51(11): 924-34, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24416927

RESUMEN

In the present study the bioactivities of chitooligosaccharides of fermented shrimp-shell hydrolysate (SSH) in respect to hypocholesterolemic, antioxidant and prebiotic activity were tested in male albino rat. Rats were treated with four different diets, viz., (i) cholesterol-rich (5%) basal diet (ChB), (ii) ChB+10% chitin, (iii) ChB+10% SSH and (iv) control group (without cholesterol). After 4 weeks of treatment, body mass index, liver weight, serum total cholesterol and LDL-cholesterol in groups (ii) and (iii) were decreased significantly than group (i). SSH supplementation significantly resists oxidative stress by reducing the thiobarbituric acid reactive substances and by increasing catalase, superoxide dismutase and free radical scavenging activity. The colonization of Lactobacillus and Bifidobacterium population in small and large intestine were more in group (iii) than other groups. Reduction of Clostridium perfringens population and non-significant changes of E. coli was also noted in SSH supplement group. Histological study revealed that the villus height and villus:crypt of the small intestine were increased significantly in SSH supplemented group (iii) without any diarrheal symptoms. The results demonstrated that the shrimp-shells hydrolysate has hypocholesterolemic effect, can resist lipid peroxidation and can influence the growth of health beneficial microbes, hence can be used as functional food for hypercholesterolemic patients.


Asunto(s)
Anticolesterolemiantes/farmacología , Antioxidantes/farmacología , Crustáceos , Fermentación , Alimentos Funcionales , Prebióticos , Animales , Cromatografía en Capa Delgada , Hidrólisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
13.
Indian J Exp Biol ; 51(11): 954-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24416930

RESUMEN

Low cost agro-waste was used as adsorption support for single-step purification of endoglucanase from the culture filtrate of A. fumigatus ABK-9. Among various agro-waste substrates, 1% NaOH pretreated rice bran was proved to be the best for adsorbing about 74.8 and 71.1% of endoglucanase at 4 degrees C and 10 degrees C respectively. Langmuir type adsorption isotherm at 4 degrees C showed maximum adsorption of enzyme at pH 5.0, which was in the range of optimum pH of the enzyme. The rice bran column bound enzyme was maximally eluted by a mixture of acetate buffer (0.05 M, pH 5.5) and ethanol (40%, v/v) at a ratio of 3:2 and a flow rate of 1 mL/min. A 5.52-fold purification of the enzyme was achieved from culture supernatant. The specific activity and recovery yield after purification were 294.0 U/mg and 40.15%, respectively, which were comparable with other contemporary protocols. The homogeneity of the enzyme was tested through sodium dodecyl sulphate polyacrylamide gel electrophoresis and a single band of 56.3 kDa was observed. Zymogram analysis finally confirmed the occurrence of endoglucanase in the single band.


Asunto(s)
Aspergillus fumigatus/enzimología , Celulasa/aislamiento & purificación , Adsorción , Celulasa/metabolismo , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Temperatura , Termodinámica
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