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1.
World J Microbiol Biotechnol ; 28(4): 1523-31, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22805934

RESUMO

The aim of this work was to determine new, different and low-cost substrates that can be used for enzyme production from the white rot fungus Trametes versicolor (ATCC 11235) by taking advantage of the broad substrate specificity of pyranose 2-oxidase. In this report, we investigated the production of pyranose 2-oxidase from T. versicolor (ATCC 11235) using ten different agricultural residues such as clover straw, almond shells, hazelnut cobs, grass and others. Pyranose 2-oxidase activity was determined as 2.332 U/g at the 9th day in a submerged culture containing clover straw and tap water shaken at 150 rpm and 26°C, and the optimum clover straw concentration was determined to be 12 g/l. The effects of different glucose, nitrogen and phosphate sources on the production of pyranose 2-oxidase were studied in the clover straw medium. Analyses of biomass, protein, reduced sugar and nitrogen concentrations were also monitored in a clover straw medium that did not contain carbon or nitrogen and phosphate sources under the parameters determined. The produced pyranose 2-oxidase was used for improving the properties of cotton fabrics.


Assuntos
Desidrogenases de Carboidrato/metabolismo , Gossypium/metabolismo , Lignina/metabolismo , Trametes/enzimologia , Meios de Cultura/química , Glucose/metabolismo , Nitrogênio/metabolismo , Fosfatos/metabolismo , Temperatura , Fatores de Tempo , Trametes/crescimento & desenvolvimento
2.
Electron. j. biotechnol ; 15(1): 3-3, Jan. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640529

RESUMO

The biodegradation kinetics of o-cresol was examined by acclimatized P. putida DSM 548 (pJP4) in batch experiments at varying initial o-cresol concentrations (from 50 to 500 mg/L). The kinetic parameters of o-cresol aerobic biodegradation were estimated by using the Haldane substrate inhibition equation. The biodegradation kinetics of o-cresol was investigated. In batch culture reactors, the Maximum specific growth rate (μmax), Monod constant (Ks) and the inhibition constant (Ki) were established as 0.519 h-1, 223.84 mg/L and 130.883 mg/L, respectively. o-cresol biodegradation in a batch-recirculation bioreactor system by immobilized P. putida was also studied. The recycled packed bed reactor system, which was composed of Ca-alginate beads and pumice on which cells immobilized, has been performed to determine possible stability for further developments.


Assuntos
Biodegradação Ambiental , Cresóis/metabolismo , Pseudomonas putida/química , Reatores Biológicos , Células Imobilizadas , Fenóis/metabolismo , Cinética
3.
Electron. j. biotechnol ; 14(2): 3-3, Mar. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-591933

RESUMO

In this study, lyophilized Trametes versicolor biomass is used as a sorbent for biosorption of a textile dye, Sirius Blue K-CFN, from an aqueous solution. The batch sorption was studied with respect to dye concentration, adsorbent dose and equilibrium time. The effect of pH and temperature on dye uptake was also investigated and kinetic parameters were determined. Optimal initial pH (3.0), equilibrium time (2 hrs), initial dye concentration ( 100 mg l-1) and biomass concentration (1.2 mg l-1) were determined at 26ºC. The maximum biosorption capacity (q max) of Sirius Blue K-CFN dye on lyophilized T. versicolor biomass is 62.62 mg/g. The kinetic and isotherm studies indicated that the biosorption process obeys to a pseudo-second order model and Langmuir isotherm model. In addition, the biosorption capacities of fungal biomass compared to other well known adsorbents such as activated carbon and Amberlite, fungal biomass biosorptions capacities were found to be more efficient.


Assuntos
Trametes/química , Biomassa , Basidiomycota/química , Corantes , Compostos Azo/química , Liofilização , Concentração de Íons de Hidrogênio , Isoterma , Cinética , Temperatura
4.
Prep Biochem Biotechnol ; 40(4): 366-76, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21108140

RESUMO

Depending upon their structure, azo- and anthraquinonic dyes are the two major classes and together represent 90% of all organic colorants. Adsorption of dye molecules onto a sorbent can be an effective, low-cost method of color removal. Most of the techniques used for removal of dyes are of high production cost, and the regeneration also makes them uneconomical. There is much interest in the development of cheaper and effective newer materials for use as adsorbents. Molecular imprinting is a new kind of materials that can be alternative adsorbents. In this study, molecularly imprinted polymers of three textile dyes (Cibacron Orange P-4R, Cibacron Red P-4B, Cibacron Black PSG) were prepared. Methacrylic acid was used as a monomer for red and orange dyes and acrylamide was used for black dye. Methanol:acetonitrile was used as a porogen. The selective recognition ability of the molecularly imprinted polymers was studied by an equilibrium-adsorption batch method. The adsorption data are for Cibacron Black PSG 65% and nonimprinted polymer (NIP) 25%; Cibacron Red P-4B 72% and NIP 18%; and Cibacron Orange P-4R 45% and NIP 10%, respectively. Dye-imprinted polymers were used as a solid-phase extraction material for selective adsorption from wastewater of textile factory.


Assuntos
Acrilamida/química , Corantes/isolamento & purificação , Metacrilatos/química , Impressão Molecular , Extração em Fase Sólida/métodos , Adsorção , Polímeros/química
5.
Water Environ Res ; 82(7): 579-85, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20669718

RESUMO

To investigate biodegradability by Trametes versicolor, five structurally different direct azo-dyes--Direct Black 38, Direct Blue 15 (DB 15), Direct Orange 26, Direct Green 6, and Direct Yellow 12--were studied. The DB 15 was determined as the best biodegradable dye by this white-rot fungus. Laccase and manganese peroxidase activities were monitored with the biodegradation process; it was observed that laccase played an important role in the dye degradation, while manganese peroxidase activity could not be detected. Possible degradation products also were examined by gas chromatography-mass spectrometry, but no metabolite was detected after the degradation and/or decolorization process. To enhance performance of the fungi during the degradation, Trametes versicolor cells were immobilized in alginate beads. Then, DB 15 decolorization by immobilized Trametes versicolor was studied in a small-scale packed-bed reactor. The color removal efficiency in repeated batches was found to be 98 and 93% for 50 mg/L DB 15.


Assuntos
Compostos Azo/metabolismo , Biodegradação Ambiental , Trametes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Lacase/metabolismo , Peroxidases/metabolismo , Trametes/enzimologia
6.
Braz. j. microbiol ; 40(2): 346-353, Apr.-June 2009. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-520222

RESUMO

This study presents new and alternative fungal strains for the production of ligninolytic enzymes which have great potential to use in industrial and biotechnological processes. Thirty autochthonous fungal strains were harvested from Bornova-Izmir in Turkiye. In the fresh fruitbody extracts laccase, manganese peroxidase and lignin peroxidase activities, which are the principal enzymes responsible for ligninocellulose degradation by Basidiomycetes, were screened. Spores of some of the basidiomycetes species such as Cortinarius sp., Trametes versicolor, Pleurotus ostreatus, Abortiporus biennis, Lyophyllum subglobisporium, Ramaria stricta, Ganoderma carnosum, Lactarius delicious ve Lepista nuda were isolated and investigated optimum cultivation conditions in submerged fermentation for high yields of ligninolytic enzyme production. In addition, isolated fungal strains were monitored on agar plates whether having the capability of decolorization of a textile dye Remazol Marine Blue.


Este estudo apresenta novas cepas de fungos produtores de enzimas ligninolíticas com potencial de aplicação em processos industriais e biotecnológicos. Trinta cepas de fungos autóctones foram obtidos em Bornova-Izmir, Turquia. Os extratos frescos dos corpos de frutificação foram submetidos à triagem de atividade de lacase, manganês peroxidase e lignina peroxidase, que são as principais enzimas de degradação de ligninocelulose pelos Basidiomycetes. Foram isolados esporos de Cortinarius sp, Tramnetes versicolor, Pleorotus ostreatus, Abortiporus biennis, Lyophyllum subglobisporium, Ramaria stricta, Ganoderma carnosum, Lactarius delicius ve Lepista desnuda, investigando-se as condições ótimas de cultivo em fermentação submersa para produção de enzimas ligninolíticas com elevado rendimento. Além disso, as cepas fúngicas isoladas foram monitoradas em placas de ágar quanto a capacidade de descoloramento do corante têxtil Remazole Marine Blue.


Assuntos
Corantes/análise , Basidiomycota/isolamento & purificação , Celulose/análise , Esporos Fúngicos/isolamento & purificação , Fermentação , Fungicidas Industriais/isolamento & purificação , Lignina/análise , Oxirredutases/análise , Ativação Enzimática , Métodos , Métodos , Indústria Têxtil
7.
Braz J Microbiol ; 40(2): 346-53, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031371

RESUMO

This study presents new and alternative fungal strains for the production of ligninolytic enzymes which have great potential to use in industrial and biotechnological processes. Thirty autochthonous fungal strains were harvested from Bornova-Izmir in Turkiye. In the fresh fruitbody extracts laccase, manganese peroxidase and lignin peroxidase activities, which are the principal enzymes responsible for ligninocellulose degradation by Basidiomycetes, were screened. Spores of some of the basidiomycetes species such as Cortinarius sp., Trametes versicolor, Pleurotus ostreatus, Abortiporus biennis, Lyophyllum subglobisporium, Ramaria stricta, Ganoderma carnosum, Lactarius delicious ve Lepista nuda were isolated and investigated optimum cultivation conditions in submerged fermentation for high yields of ligninolytic enzyme production. In addition, isolated fungal strains were monitored on agar plates whether having the capability of decolorization of a textile dye Remazol Marine Blue.

8.
Prep Biochem Biotechnol ; 39(1): 32-45, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19090419

RESUMO

Optimization of pyranose-2-oxidase (P2O) production conditions from Trametes versicolor was carried out in shaking cultures containing glucose, malt, and yeast extracts; the optimum concentration values were found to be 1.5% glucose, 1.0% yeast extract, and 1.0% malt extract, pH 5.0, temperature, 26 degrees C, and agitation rate 150 rpm. For the first time, P2O production was also carried out in a stirred tank reactor (STR) with 2.2 L working volume in the optimized medium composition, and biomass, P2O activity, protein, nitrogen and glucose concentrations were also monitored besides pH and dissolved oxygen (DO). In the STR, P2O activity peaked on day 9. Partial enzyme characterization occurred and optimum pH and temperature were detected as 7.0 and 37 degrees C, respectively. K(m) value was found to be 1.009 mM.


Assuntos
Reatores Biológicos/microbiologia , Desidrogenases de Carboidrato/química , Desidrogenases de Carboidrato/metabolismo , Trametes/classificação , Trametes/enzimologia , Ativação Enzimática , Estabilidade Enzimática , Especificidade da Espécie
9.
Prep Biochem Biotechnol ; 38(1): 1-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18080906

RESUMO

Manganese-dependent peroxidase (MnP) production was performed in an immobilized cell bioreactor in which Phanerochaete chrysosporium BKM-F-1767 was immobilized on polystyrene foam. The immobilized cell culture yielded significantly greater MnP activity than the conventional stationary liquid culture. Cultivation was carried out in batch mode; the effect of glucose concentration was investigated and growth kinetics parameters were found as, micromax=0.59 day(-1), Ks=0.33 g/L and Kss=14.5. Batch operation led to maximum MnP (770.82 U/L) in the culture medium containing 0.05% Tween 80, 10 g/L glucose, and 174 microM Mn2+ at 37 degrees C and pH 4.5. Enzyme productivity was obtained as 110.12 U/day/L.


Assuntos
Reatores Biológicos , Peroxidases/biossíntese , Phanerochaete/enzimologia , Células Cultivadas , Células Imobilizadas , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Phanerochaete/citologia , Poliestirenos/química , Temperatura
10.
Braz. arch. biol. technol ; 50(6): 913-920, Nov. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-476217

RESUMO

Production of manganese-dependent peroxidase (MnP) by the white-rot fungus Phanerochaete chrysosporium BKM-F-1767 (ATCC 24725) was monitored during growth in different media and growth conditions. The effect of some activators of MnP production, Mn2+, Tween 80, phenylmethylsulphonylfloride (PMSF), oxygen, temperature, pH, glycerol and nitrogen was studied. Supplementing the cultures with Tween 80 (0.05 percent, v/v) and Mn2+ (174 µM) resulted a maximum MnP activity of 356 U/L which was approximately two times higher than that obtained in the control culture (without Tween 80). Decolourisation of Direct Blue 15 and Direct Green 6 (50 mg/L) was also achieved with MnP.

11.
Artigo em Inglês | MEDLINE | ID: mdl-15974183

RESUMO

Phanerochaete chrysosporium BKMF-1767 cells were immobilized on different carriers. The optimum carrier according to adsorbed P. chrysosporium cells number (86.38%) was determined to be polystyrene foam, a novel carrier. The conditions for the immobilization of cells on polystyrene foam were optimized and determined as 50 rpm, 37 degrees C, and 2h. The results show that the adsorption of P. chrysosporium on polystyrene foam follows the Langmuir adsorption isotherm. High manganese peroxidase activity (421 U/L) and dry mass (4.7 g/L) were recovered from the batch mode polystyrene foam solid state fermentation system.


Assuntos
Reatores Biológicos/microbiologia , Proteínas Fúngicas/biossíntese , Peroxidases/biossíntese , Phanerochaete/crescimento & desenvolvimento , Plásticos/química , Células Imobilizadas/metabolismo
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