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1.
Bioprocess Biosyst Eng ; 47(1): 39-55, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37962643

RESUMEN

Phytase enzyme found in plants, animals, and microorganisms is mainly involved in catalyzing the systematic removal of a phosphate group from phytic acid. Enzyme immobilization is one of the cost-effective methods for the wide usage of enzymes in the industrial sector. This paper reports the covalent immobilization of phytase on glutaraldehyde-activated aluminum oxide beads. The immobilization yield, efficiency, and activation energy were found to be 47.8%, 71.5%, and 15.78 J/mol, respectively. The bound enzyme displayed a shift in pH optima from 5.5 to 4.5, which is more beneficial to increase digestibility in comparison with the free enzyme. Immobilized phytase retained 42.60% of its activity after 1.0 h incubation at 80 °C, whereas free enzyme retained only 4.20% of its activity. Thermodynami increase in half-lives, D-values, enthalpy and free energy change after covalent immobilization could be credited to the enhanced stability. Immobilized phytase could be reused for five consecutive cycles retaining 51% of its initial activity with sodium phytate. The immobilized phytase was also found effective to hydrolyze the soybean meal, thus increasing the digestibility of poultry feed. The hydrolyzing reaction of soybean meal was carried out for six consecutive cycles and immobilized phytase retained nearly 50% of activity till the fifth cycle. The amount of phosphorus released after treatment with immobilized phytase was far higher than that from free phytase. Immobilization on this support is significant, as this support can sustain high mechanical resistance at high pH and temperature. This considerable stability and reusability of the bound enzyme may be advantageous for its industrial application.


Asunto(s)
6-Fitasa , Aspergillus oryzae , 6-Fitasa/química , Aspergillus oryzae/metabolismo , Células Inmovilizadas/metabolismo , Harina , Glycine max , Fosfatos , Ácido Fítico/metabolismo
2.
Prep Biochem Biotechnol ; 54(6): 819-829, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38152875

RESUMEN

The study aims to statistically optimize the phytase production by Penicillium oxalicum PBG30 in solid-state fermentation using wheat bran as substrate. Variables viz. pH, incubation days, MgSO4, and Tween-80 were the significant parameters identified through the Plackett-Burman design (PBD) that majorly influenced the phytase production. Further, central composite design (CCD) method of response surface methodology (RSM) defined the optimum values for these factors i.e., pH 7.0, 5 days of incubation, 0.75% of MgSO4, and 3.5% of Tween-80 that leads to maximum phytase production of 475.42 U/g DMR. Phytase production was also sustainable in flasks and trays of different sizes with phytase levels ranging from 394.95 to 475.42 U/g DMR. Enhancement in phytase production is 5.6-fold as compared to unoptimized conditions. The in-vitro dephytinization of feed showed an amelioration in the nutritive value by releasing inorganic phosphate and other nutrients in a time-dependent manner. The highest amount of inorganic phosphate (33.986 mg/g feed), reducing sugar (134.4 mg/g feed), and soluble protein (115.52 mg/g feed) was achieved at 37 °C with 200 U of phytase in 0.5 g feed for 48 h. This study reports the economical and large-scale production of phytase with applicability in enhancing feed nutrition.


Asunto(s)
6-Fitasa , Fermentación , Penicillium , 6-Fitasa/metabolismo , 6-Fitasa/biosíntesis , Penicillium/metabolismo , Penicillium/enzimología , Concentración de Iones de Hidrógeno , Alimentación Animal/análisis , Fibras de la Dieta/metabolismo , Aditivos Alimentarios/metabolismo
3.
Crit Rev Food Sci Nutr ; 63(22): 5465-5487, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34965785

RESUMEN

Phytases are the most widely used food and feed enzymes, which aid in nutritional improvement by reducing anti-nutritional factor. Despite the benefits, enzymes usage in the industry is restricted by several factors such as their short life-span and poor reusability, which result in high costs for large-scale utilization at commercial scale. Furthermore, under pelleting conditions such as high temperatures, pH, and other factors, the enzyme becomes inactive due to lesser stability. Immobilization of phytases has been suggested as a way to overcome these limitations with improved performance. Matrices used to immobilize phytases include inorganic (Hydroxypatite, zeolite, and silica), organic (Polyacrylamide, epoxy resins, alginate, chitosan, and starch agar), soluble matrix (Polyvinyl alcohol), and nanomaterials including nanoparticles, nanofibers, nanotubes. Several surface analysis methods, including thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and FTIR analysis, have been used to characterize immobilized phytase. Immobilized phytases have been used in a broad range of biotechnological applications such as animal feed, biodegradation of food phytates, preparations of myo-inositol phosphates, and sulfoxidation by vanadate-substituted peroxidase. This article provides information on different matrices used for phytase immobilization from the last two decades, including the process of immobilization and support material, surface analysis techniques, and multifarious biotechnological applications of the immobilized phytases.


Asunto(s)
6-Fitasa , Animales , 6-Fitasa/química , 6-Fitasa/metabolismo , Biotecnología , Alimentación Animal , Calor , Fosfatos de Inositol
4.
Lett Appl Microbiol ; 76(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36763800

RESUMEN

Microbial phytases are potentially excellent candidates for eliminating anti-nutrient i.e. phytic acid, due to hydrolysis of phospho-monoester linkages present in the phytic acid. An average 2.29-fold increase in phytase production was obtained after statistical optimization in solid-state fermentation. Aspergillus oryzae SBS50 phytase was immobilized on a Ca-alginate matrix with an effectiveness of 53%. Immobilized-phytase retained > 50% activity after recycling for five cycles and also displayed more stability in the presence of organic solvents, metal ions, and detergents as compared to free enzyme. Values of Km and Vmax of immobilized phytase were recorded as 0.66 mM and 666.6 nmol/sec, respectively. Immobilized phytase efficiently hydrolyzed the phytate contents in wheat and pearl millet flours, exhibiting > 70% catalytic activity even after three cycles. Phytase supplementation resulted in the improved nutritional quality of these flours. Furthermore, the safety assessment of the treated and untreated samples reveals the absence of any aflatoxin in the phytase produced by the mould. The results revealed the improved stability of phytase after immobilization and as a safe and significant additive for application in the food industry.


Asunto(s)
6-Fitasa , Aspergillus oryzae , Ácido Fítico , Hidrólisis , Suplementos Dietéticos , Alimentación Animal
5.
World J Microbiol Biotechnol ; 40(1): 22, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38008864

RESUMEN

Phytases are important enzymes used for eliminating the anti-nutritional properties of phytic acid in food and feed ingredients. Phytic acid is major form of organic phosphorus stored during seed setting. Monogastric animals cannot utilize this phytate-phosphorus due to lack of necessary enzymes. Therefore, phytic acid excretion is responsible for mineral deficiency and phosphorus pollution. Phytases have been reported from diverse microorganisms, however, fungal phytases are preferred due to their unique properties. Aspergillus species are the predominant producers of phytases and have been explored widely as compared to other fungi. Solid-state fermentation has been studied as an economical process for the production of phytases to utilize various agro-industrial residues. Mixed substrate fermentation has also been reported for the production of phytases. Physical and chemical parameters including pH, temperature, and concentrations of media components have significantly affected the production of phytases in solid state fermentation. Fungi produced high levels of phytases in solid state fermentation utilizing economical substrates. Optimization of culture conditions using different approaches has significantly improved the production of phytases. Fungal phytases are histidine acid phosphatases exhibiting broad substrate specificity, are relatively thermostable and protease-resistant. These phytases have been found effective in dephytinization of food and feed samples with concomitant liberation of minerals, sugars and soluble proteins. Additionally, they have improved the growth of plants by increasing the availability of phosphorus and other minerals. Furthermore, phytases from fungi have played an important roles in bread making, semi-synthesis of peroxidase, biofuel production, production of myo-inositol phosphates and management of environmental pollution. This review article describes the production of fungal phytases in solid state fermentation and their biotechnological applications.


Asunto(s)
6-Fitasa , Animales , 6-Fitasa/química , 6-Fitasa/metabolismo , Fermentación , Ácido Fítico/metabolismo , Fósforo , Minerales
6.
Appl Microbiol Biotechnol ; 106(2): 505-521, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35015145

RESUMEN

Probiotics have been considered as an economical and safe alternative for the treatment of a large number of chronic diseases and improvement of human health. They are known to modulate the host immunity and protect from several infectious and non-infectious diseases. The colonization, killing of pathogens and induction of host cells are few of the important probiotic attributes which affect several functions of the host. In addition, prebiotics and non-digestible food substances selectively promote the growth of probiotics and human health through nutrient enrichment, and modulation of gut microbiota and immune system. This review highlights the role of probiotics and prebiotics alone and in combination (synbiotics) in the modulation of immune system, treatment of infections, management of inflammatory bowel disease and cancer therapy. KEY POINTS: • Probiotics and their derivatives against several human diseases. • Prebiotics feed probiotics and induce several functions in the host. • Discovery of novel and biosafe products needs attention for human health.


Asunto(s)
Microbioma Gastrointestinal , Enfermedades Inflamatorias del Intestino , Probióticos , Simbióticos , Humanos , Prebióticos
7.
Prep Biochem Biotechnol ; 52(2): 197-209, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34010094

RESUMEN

Production of cellulolytic and xylanolytic enzymes by Sporotrichum thermophile was enhanced using response surface methodology in solid-state fermentation (SSF) using wheat straw and cotton oil cake. Cellulolytic and xylanolytic enzymes were partially purified by ammonium sulfate precipitation followed by ion exchange and gel filtration chromatographic techniques. Xylanase of S. thermophile is neutral xylanase displaying optimal activity at 60 °C with Km and Vmax values of 0.2 mg/mL and 238.05 µmole/min, respectively. All cellulases produced by the thermophilic mold showed optimal activity at pH 5.0 and 60 °C with Km values of 0.312 mg/mL, 0.113 mg/mL, and 0.285 mM for carboxymethyl cellulase (CMCase), filter paper cellulase (FPase), and ß-glucosidase, respectively and while Vmax values were 181.81, 138.88, and 66.67 µmole/min, respectively. The presence of various metal ions (Ca2+ and Co2+), chemical reagent (glutaraldehyde), and surfactants (Tween 80 and Triton X-100) significantly improved the activities of all enzymes. All the enzymes showed high storage stability under low temperature (-20 and 4 °C) conditions. Cellulolytic and xylanolytic enzymes resulted in enhanced liberation of reducing sugars (356.34 mg/g) by hydrolyzing both cellulosic and hemicellulosic fractions of ammonia-pretreated rice straw as compared to other pretreatment methods used in the study. Fermentation of enzymatic hydrolysate resulted in the formation of 28.88 and 27.18 g/L of bioethanol in separate hydrolysis and fermentation (SHF) process by Saccharomyces cerevisiae and Pichia stipitis, respectively. Therefore, cellulolytic and xylanolytic enzymes of S. thermophile exhibited ideal properties of biocatalysts useful in the saccharification of cellulosic and hemicellulosic fractions of rice straw for the production of bioethanol.


Asunto(s)
Celulosa/metabolismo , Endo-1,4-beta Xilanasas/metabolismo , Etanol/metabolismo , Oryza/metabolismo , Sporothrix/enzimología , Celulasa/metabolismo , Fermentación , Hidrólisis
8.
Bioprocess Biosyst Eng ; 44(7): 1539-1555, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33765291

RESUMEN

Endoxylanase production from M. thermophila BJTLRMDU3 using rice straw was enhanced to 2.53-fold after optimization in solid state fermentation (SSF). Endoxylanase was purified to homogeneity employing ammonium sulfate precipitation followed by gel filtration chromatography and had a molecular mass of ~ 25 kDa estimated by SDS-PAGE. Optimal endoxylanase activity was recorded at pH 5.0 and 60 °C. Purified enzyme showed complete tolerance to n-hexane, but activity was slightly inhibited by other organic solvents. Among surfactants, Tweens (20, 60, and 80) and Triton X 100 slightly enhanced the enzyme activity. The Vmax and Km values for purified endoxylanase were 6.29 µmol/min/mg protein and 5.4 mg/ml, respectively. Endoxylanase released 79.08 and 42.95% higher reducing sugars and soluble proteins, respectively, which control after 48 h at 60 °C from poultry feed. Synergistic effect of endoxylanase (100 U/g) and phytase (15 U/g) on poultry feed released higher amount of reducing sugars (58.58 mg/feed), soluble proteins (42.48 mg/g feed), and inorganic phosphate (28.34 mg/feed) in contrast to control having 23.55, 16.98, and 10.46 mg/feed of reducing sugars, soluble proteins, and inorganic phosphate, respectively, at 60 °C supplemented with endoxylanase only.


Asunto(s)
Alimentación Animal , Endo-1,4-beta Xilanasas/química , Sordariales/metabolismo , 6-Fitasa/química , Cromatografía en Gel , Fermentación , Concentración de Iones de Hidrógeno , Octoxinol/química , Compuestos Orgánicos , Oryza , Solventes/química , Azúcares/química , Tensoactivos/química , Temperatura , Agua/química
9.
Prep Biochem Biotechnol ; 51(7): 697-704, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33302792

RESUMEN

Optimization of cellulase production by Bacillus subtilis subsp. subtilis JJBS300 resulted in maximum cellulase (CMCase 9.7 U/g substrate) using wheat bran and rice straw in 1:1 ratio at substrate to moisture ratio of 1:3 at 35 °C and pH 4.0 after 48 h. Partially purified cellulase of B. subtilis subsp. subtilis showed optimal activity at 50 °C and pH 5.0. Among the metal ions, Na+, Ca2+ and Fe2+ stimulated the cellulase activity. Glutaraldehyde and 1-butanol also enhanced the cellulase activity as compared to other solvents. Bacterial cellulase hydrolyzed ammonia-pretreated rice straw more efficiently as compared to sodium-carbonate pretreated and untreated biomass. Optimization of saccharification of untreated and pretreated (sodium carbonate and ammonia) rice straw by bacterial cellulase resulted in high liberation of reducing sugars with enzyme dose of 100 U/g substrate (221 mg/g substrate) at pH 5.0 (103 mg/g substrate) and 50 °C (142 mg/g substrate) after 6 h in ammonia-pretreated rice straw. Furthermore, liberation of reducing sugars increased with incubation time showing maximum reducing sugars (171 mg/g substrate) after 24 h in ammonia-pretreated rice straw. HPLC analysis of enzymatic hydrolysate of ammonia-pretreated rice straw verified the ability of bacterial cellulase in liberation of various monomeric and oligomeric sugars.


Asunto(s)
Amoníaco/química , Bacillus subtilis/enzimología , Proteínas Bacterianas/biosíntesis , Biocatálisis , Celulasa/biosíntesis , Oryza/química , Proteínas Bacterianas/química , Carbonatos/química , Celulasa/química
10.
Bioprocess Biosyst Eng ; 43(6): 1081-1091, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32065289

RESUMEN

An investigation was carried out using sugarcane bagasse as the agricultural residue to study the optimization of xylanase production by solid-state fermentation. Maximum xylanase production (20.35 U/g substrate) was achieved by Bacillus substilis subsp. subtilis JJBS250 using 'one variable at a time approach' at pH 7.0, 40 °C after 48 h. After statistical optimization by response surface methodology (RSM) there was 4.82-fold improvement in xylanase production (98.16 U/g substrate). Further optimization of untreated and sodium carbonate pretreated sugarcane bagasse enzymatic hydrolysis was carried out using both bacterial (Bacillus substilis subsp. subtilis JJBS250) and fungal (Myceliophthora thermophila BJTLRMDU3) xylanases that showed high amount of reducing sugar liberation from untreated sugarcane bagasse (124.24 mg/g substrate) as compared to pretreated (76.23 mg/g substrate) biomass. Furthermore, biophysical characterization of untreated and sodium carbonate pretreated sugarcane bagasse using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM), revealed the structural changes in the pretreated biomass.


Asunto(s)
Bacillus subtilis/enzimología , Proteínas Bacterianas/biosíntesis , Celulosa/metabolismo , Endo-1,4-beta Xilanasas/biosíntesis , Saccharum , Sordariales/enzimología
11.
Appl Microbiol Biotechnol ; 103(21-22): 8763-8784, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31641815

RESUMEN

Microbial xylanases have gathered great attention due to their biotechnological potential at industrial scale for many processes. A variety of lignocellulosic materials, such as sugarcane bagasse, rice straw, rice bran, wheat straw, wheat bran, corn cob, and ragi bran, are used for xylanase production which also solved the great issue of solid waste management. Both solid-state and submerged fermentation have been used for xylanase production controlled by various physical and nutritional parameters. Majority of xylanases have optimum pH in the range of 4.0-9.0 with optimum temperature at 30-60 °C. For biochemical, molecular studies and also for successful application in industries, purification and characterization of xylanase have been carried out using various appropriate techniques. Cloning and genetic engineering are used for commercial-level production of xylanase, to meet specific economic viability and industrial needs. Microbial xylanases are used in various biotechnological applications like biofuel production, pulp and paper industry, baking and brewing industry, food and feed industry, and deinking of waste paper. This review describes production, characteristics, and biotechnological applications of microbial xylanases.


Asunto(s)
Bacterias/enzimología , Bacterias/metabolismo , Reactores Biológicos/microbiología , Endo-1,4-beta Xilanasas/metabolismo , Lignina/metabolismo , Biocombustibles/microbiología , Endo-1,4-beta Xilanasas/química , Fermentación/fisiología , Ingeniería Genética/métodos
12.
Phytother Res ; 33(9): 2163-2178, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31290201

RESUMEN

Ageratum conyzoides L. (Asteraceae) is an invasive aromatic herb with immense therapeutic importance. The herb is distributed in tropical and subtropical regions. A. conyzoides has imparted numerous ethnomedicinal uses because it has been used to cure various ailments that include leprosy, skin disorders, sleeping sickness, rheumatism, headaches, dyspnea, toothache, pneumonia and many more. A number of phytoconstituents have been scrutinized such as alkaloids, flavonoids, terpenes, chromenes, and sterols from almost every part of this plant. These phytoconstituents have shown diverse pharmacological properties including antimicrobial, anti-inflammatory, analgesic, antioxidant, anticancer, antiprotozoal, antidiabetic, spasmolytic, allelopathy, and many more. The plant A. conyzoides has provided a platform for doing pharmaceutical and toxicological research in order to isolate some promising active compounds and authenticate their safety in clinical uses. A. conyzoides provides principal information for advanced studies in the field of pharmaceutical industries and agriculture. Present review article describes the cytogenetics, ethnobotany, phytochemistry, pharmacology, and toxicological aspects of A. conyzoides.


Asunto(s)
Ageratum/química , Etnofarmacología/métodos , Fitoquímicos/uso terapéutico , Fitoterapia/métodos , Humanos , Fitoquímicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología
13.
Prep Biochem Biotechnol ; 48(8): 718-724, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30015561

RESUMEN

A novel protease-resistant and thermostable phytase from Bacillus subtilis subsp. subtilis JJBS250 was purified 36-fold to homogeneity with a combination of ammonium sulfate precipitation followed by Q-Sepharose and Sephadex G-50 chromatographic techniques. The estimated molecular mass of the purified phytase was 46 kDa by electrophoresis with optimal activity at pH 7.0 and 70 °C. About 19% of original activity was maintained at 80 °C for 10 min. Phytase activity was stimulated in presence of surfactants like Tween-20, Tween-80, and Triton X-100 and metal ions like Ca+2, K+, and Co+2 and it was inhibited by SDS and Mg+2, Al+2, and Fe+2. Purified enzyme showed specificity to different salts of phytic acid and values of Km and Vmax were 0.293 mM and 11.49 nmoles s-1, respectively for sodium phytate. The purified enzyme was resistant to proteases (trypsin and pepsin) that resulted in amelioration of food nutrition with simultaneous release of inorganic phosphate, reducing sugars, and soluble protein.


Asunto(s)
6-Fitasa , Bacillus subtilis/enzimología , Proteínas Bacterianas , Calor , Pepsina A/química , Tripsina/química , 6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Estabilidad de Enzimas
14.
World J Microbiol Biotechnol ; 33(6): 109, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28466305

RESUMEN

Sporotrichum thermophile BJAMDU5 secreted high titres of xylanolytic and cellulolytic enzymes in solid state fermentation using mixture of wheat straw and cotton oil cake (ratio 1:1) at 45 °C, pH 5.0 after 72 h inoculated with 2.9 × 107 CFU/mL conidiospores. Supplementation of solid medium with lactose and ammonium sulphate further enhanced the production of hydrolytic enzymes. Among different surfactants studied, Tween 80 enhanced the production of all enzymes [3455 U/g DMR (dry mouldy residue), 879.26 U/g DMR, 976.28 U/g DMR and 35.10 U/g DMR for xylanase, CMCase (Carboxymethylcellulase), FPase (Filter paper activity) and ß-glucosidase, respectively] as compared to other surfactants. Recycling of solid substrate reduced the production of all these enzymes after second cycle. End products analysis by TLC showed the ability of hydrolytic enzymes of S. thermophile to liberate monomeric (xylose and glucose) as well as oligomeric (xylobiose, cellobiose and higher ones) sugars. Supplementation of enzyme resulted in improved nutritional properties of the bread. Formation of oligomeric sugars by xylanase enzyme of S. thermophile BJAMDU5 make it a good candidate in food industry.


Asunto(s)
Celulasas/metabolismo , Industria de Alimentos/métodos , Sporothrix/fisiología , Xilosidasas/metabolismo , Sulfato de Amonio/metabolismo , Pan , Fermentación , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Lactosa/metabolismo , Sporothrix/enzimología , Temperatura
15.
Crit Rev Microbiol ; 42(6): 985-1006, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26777293

RESUMEN

Thermophilic molds thrive in a variety of natural habitats including soils, composts, wood chip piles, nesting materials of birds and other animals, municipal refuse and others, and ubiquitous in their distribution. These molds grow in simple media containing carbon and nitrogen sources and mineral salts. Polyamines are synthesized in these molds and the composition of lipids varies considerably, predominantly containing palmitic, oleic and linoleic acids with low levels of lauric, palmiotoleic and stearic acids. Thermophilic molds are capable of efficiently degrading organic materials by secreting thermostable enzymes, which are useful in the bioremediation of industrial wastes and effluents that are rich in oil, heavy metals, anti-nutritional factors such as phytic acid and polysaccharides. Thermophilic molds synthesize several antimicrobial substances and biotechnologically useful miscellaneous enzymes. The analysis of genomes of thermophilic molds reveals high G:C contents, shorter introns and intergenic regions with lesser repetitive sequences, and further confirms their ability to degrade agro-residues efficiently. Genetic engineering has aided in ameliorating the characteristics of the enzymes of thermophilic molds. This review is aimed at focusing on the biology of thermophilic molds with emphasis on recent developments in the analysis of genomes, genetic engineering and potential applications.


Asunto(s)
Hongos/metabolismo , Animales , Antibacterianos/metabolismo , Biodegradación Ambiental , Biotecnología , Contaminantes Ambientales/metabolismo , Hongos/química , Hongos/genética , Calor , Metales Pesados/metabolismo
16.
Crit Rev Biotechnol ; 36(1): 59-69, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25025273

RESUMEN

Myceliophthora thermophila syn. Sporotrichum thermophile is a ubiquitous thermophilic mould with a strong ability to degrade organic matter during optimal growth at 45 °C. Both genome analysis and experimental data have suggested that the mould is capable of hydrolyzing all major polysaccharides found in biomass. The mould is able to secrete a large number of hydrolytic enzymes (cellulases, laccases, xylanases, pectinases, lipases, phytases and some other miscellaneous enzymes) employed in various biotechnological applications. Characterization of the biomass-hydrolyzing activity of wild and recombinant enzymes suggests that this mould is highly efficient in biomass decomposition at both moderate and high temperatures. The native enzymes produced by the mould are more efficient in activity than their mesophilic counterparts beside their low enzyme titers. The mould is able to synthesize various biomolecules, which are used in multifarious applications. Genome sequence data of M. thermophila also supported the physiological data. This review describes the biotechnological potential of thermophilic mould, M. thermophila supported by genomic and experimental evidences.


Asunto(s)
Biotecnología , Genoma Fúngico , Sordariales/metabolismo , Biomasa , Celulasas , Hidrólisis , Lipasa/genética , Lipasa/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo , Sordariales/genética
17.
Bioprocess Biosyst Eng ; 39(1): 181-91, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26581490

RESUMEN

Economical production of xylanase and three cellulases, endo-ß-1,4-glucanase (CMCase), exo-ß-1,4-glucanase (FPase), ß-glucosidase (BGL) was studied in submerged fermentation using cane molasses medium. A statistical optimization approach involving Plackett-Burman design and response surface methodology (RSM) resulted in the production of 72,410, 36,420, 32,420 and 5180 U/l of xylanase, CMCase, FPase and ß-glucosidase, respectively. Optimization resulted in more than fourfold improvements in production of xylanolytic and cellulolytic enzymes. Scale up of enzymes production in shake flasks of varied volumes was sustainable, suggesting a good scope for large scale enzyme production. Addition of microparticles engineered fungal morphology and enhanced enzymes production. Xylanase of S. thermophile is a neutral xylanase displaying its optimal activity at 60 °C while all the cellulases are optimally active at pH 5.0 and 60 °C. The efficacy of enzyme cocktail in waste tea cup paper and rice straw hydrolysis showed that maximum sugar yield of 578.12 and 421.79 mg/g substrate for waste tea cup and rice straw, respectively, were achieved after 24 h. Therefore, concomitant production of cellulolytic and xylanolytic enzymes will be beneficial for the saccharification of lignocellulosics in generating both monomeric and oligomeric sugars for biofuels and other biotechnological applications.


Asunto(s)
Celulasas/química , Endo-1,4-beta Xilanasas/química , Proteínas Fúngicas/química , Sporothrix/enzimología , Celulasas/biosíntesis , Celulasas/economía , Endo-1,4-beta Xilanasas/biosíntesis , Endo-1,4-beta Xilanasas/economía , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/economía , Calor , Concentración de Iones de Hidrógeno
18.
Cell Microbiol ; 15(8): 1341-56, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23387921

RESUMEN

Host cell invasion by Plasmodium falciparum requires multiple molecular interactions between host receptors and parasite ligands. A family of parasite proteins, which contain the conserved thrombospondin structural repeat motif (TSR), has been implicated in receptor binding during invasion. In this study we have characterized the functional role of a TSR containing blood stage protein referred to as P. falciparum thrombospondin related apical merozoite protein (PfTRAMP). Both native and recombinant PfTRAMP bind untreated as well as neuraminidase, trypsin or chymotrypsin-treated human erythrocytes. PfTRAMP is localized in the rhoptry bulb and is secreted during invasion. Adhesion of microneme protein EBA175 with its erythrocyte receptor glycophorin A provides the signal that triggers release of PfTRAMP from the rhoptries. Rabbit antibodies raised against PfTRAMP block erythrocyte invasion by P. falciparum suggesting that PfTRAMP plays an important functional role in invasion. Combination of antibodies against PfTRAMP with antibodies against microneme protein EBA175 provides an additive inhibitory effect against invasion. These observations suggest that targeting multiple conserved parasite ligands involved in different steps of invasion may provide an effective strategy for the development of vaccines against blood stage malaria parasites.


Asunto(s)
Eritrocitos/parasitología , Plasmodium falciparum/patogenicidad , Proteínas Protozoarias/análisis , Proteínas Protozoarias/fisiología , Trombospondinas/análisis , Trombospondinas/fisiología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Antígenos de Protozoos/efectos de los fármacos , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/metabolismo , Células Cultivadas , Eritrocitos/metabolismo , Glicoforinas/metabolismo , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Ratones , Modelos Animales , Unión Proteica/fisiología , Proteínas Protozoarias/efectos de los fármacos , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/metabolismo , Conejos , Transducción de Señal/fisiología
19.
J Infect Dis ; 207(11): 1664-74, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23448726

RESUMEN

BACKGROUND: Antibodies against VAR2CSA, the Plasmodium falciparum variant surface antigen that binds placental chondroitin sulfate A, have been suggested to mediate protection against malaria in pregnancy but also to be markers of infection. Here, we aimed to identify clinically relevant antibody responses, taking into consideration variations in parasite exposure and human immunodeficiency virus type 1 (HIV) infection status. METHODS: Levels of immunoglobulin G (IgG) against placental and pediatric isolates, VAR2CSA (DBL2X, DBL3X, DBL5ε, and DBL6ε domains), and other blood-stage antigens (DBLγ, DBLα, MSP119, AMA1, and EBA175) were measured in plasma specimens from 293 pregnant Mozambican women at delivery. Associations between antibody responses, factors influencing malaria exposure, HIV infection status, and pregnancy outcomes were assessed. RESULTS: Maternal antibodies were affected by placental infection, parity, season, and neighborhood of residence. HIV infection modified these associations and attenuated the parity-dependent increase in IgG level. High levels of antibody against AMA1, DBL3X, DBL6ε, placental isolates, and pediatric isolates were associated with increased weight and gestational age of newborns (P ≤ .036) among women with malaria episodes during pregnancy. CONCLUSIONS: Antiparasite IgGs in women at delivery are affected by HIV infection, as well as by variations in the exposure to P. falciparum. Heterogeneity of malaria transmission needs to be considered to identify IgGs against VAR2CSA and other parasite antigens associated with improved pregnancy outcomes.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Malaria Falciparum/inmunología , Plasmodium falciparum/inmunología , Complicaciones Infecciosas del Embarazo/inmunología , Adolescente , Adulto , Antígenos de Protozoos/inmunología , Femenino , Infecciones por VIH/complicaciones , Humanos , Inmunoglobulina G/sangre , Embarazo , Resultado del Embarazo , Adulto Joven
20.
Int J Biol Macromol ; : 135740, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39304049

RESUMEN

Among different microbes, fungi are proficient candidates for the extracellular synthesis of iron nanoparticles. For biogenic synthesis of iron nanoparticles, a thermophilic mould Myceliophthora thermophila BJTLRMDU7 was used in this study. Mycogenic magnetic nanoparticles were used for phosphatase immobilization and therapeutic applications such as antimicrobial and antimalarial activity. Firstly, the phosphatase was immobilized on biogenic iron nanoparticles with an efficiency of >56 %. Immobilized enzyme was optimally active at 60 °C and pH 5. Immobilized phosphatase was recycled using external magnetic field up to 4th cycle retaining >50 % activity. The immobilized phosphatase efficiently released inorganic phosphate from different flours such as wheat, maize and gram at 37 °C and 60 °C. There was continuous increase in the release of inorganic phosphorus from all samples with incubation time at 37 °C and slight reduction at 60 °C. These nanoparticles showed the effective antimicrobial activity against Bacillus subtilis, Escherichia coli and Myceliophthora thermophila. Further, the synthesized iron nanoparticles showed antimalarial potential against Plasmodium falciparum. Biogenic nanoparticles did not exhibit hemolytic activity and cytotoxicity. Therefore, biogenic iron nanoparticles could be used as a suitable matrix for immobilization of enzymes and safe therapeutics.

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