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Mohamed Neifar - One of the best experts on this subject based on the ideXlab platform.
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doi:10.4061/2011/368525 Research Article Application of Asymetrical and Hoke Designs for Optimization of Laccase Production by the White-Rot Fungus Fomes Fomentarius in Solid-State Fermentation
2016Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Amel Kamoun, Semia Ellouze-chaabouniAbstract:Copyright © 2011 Mohamed Neifar et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Statistical approaches were employed for the optimization of different cultural parameters for the production of laccase by the white rot fungus Fomes Fomentarius MUCL 35117 in wheat bran-based solid medium. first, screening of production parameters was performed using an asymmetrical design 2533//16, and the variables with statistically significant effects on laccase production were identified. Second, inoculum size, CaCl2 concentration, CuSO4 concentration, and incubation time were selected for further optimization studies using a Hoke design. The application of the response surface methodology allows us to determine a set of optimal conditions (CaCl2, 5.5mg/gs, CuSO4, 2.5mg/gs, inoculum size, 3 fungal discs (6mmØ), and 13 days of static cultivation). Experiments carried out under these conditions led to a laccase production yield of 150U/g dry substrate. 1
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improving the nutritive value of olive cake by solid state cultivation of the medicinal mushroom Fomes Fomentarius
Chemosphere, 2013Co-Authors: Mohamed Neifar, Atef Jaouani, Amani Ayari, Olfa Abid, Hichem Ben Salem, Abdellatif Boudabous, Taha Najar, Raoudha Ellouze GhorbelAbstract:Abstract Olive Cake (OC) generated by the olive oil industries, well implanted in Tunisia, represents a major disposal and potentially severe pollution problem. This work presents the study of bioconversion of OC in solid state fermentation with the medicinal mushroom, Fomes Fomentarius so as to upgrade its nutritional values and digestibility for its use as ruminants feed. The fungus was cultured on OC for 7–30 d, and subsequently the chemical composition, lignocellulolytic enzyme activities and in vitro digestibility of the resultant substrate were determined. The results obtained showed an increase in the crude protein ranging from 6% to 22% for the control and for treated OC, respectively. Significant ( P in vitro digestibility improved from 9% (control) to 25% (treated OC). The present findings revealed F. Fomentarius to be an efficient organism for lignocellulolytic enzymes production and simultaneous enhancement in crude protein and in vitro digestibility of OC.
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Application of Asymetrical and Hoke Designs for Optimization of Laccase Production by the White-Rot Fungus Fomes Fomentarius in Solid-State Fermentation
Enzyme Research, 2011Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Amel Kamoun, Semia Ellouze-chaabouniAbstract:Statistical approaches were employed for the optimization of different cultural parameters for the production of laccase by the white rot fungus Fomes Fomentarius MUCL 35117 in wheat bran-based solid medium. first, screening of production parameters was performed using an asymmetrical design 2533//16, and the variables with statistically significant effects on laccase production were identified. Second, inoculum size, CaCl2 concentration, CuSO4 concentration, and incubation time were selected for further optimization studies using a Hoke design. The application of the response surface methodology allows us to determine a set of optimal conditions (CaCl2, 5.5 mg/gs, CuSO4, 2.5 mg/gs, inoculum size, 3 fungal discs (6 mm O), and 13 days of static cultivation). Experiments carried out under these conditions led to a laccase production yield of 150 U/g dry substrate.
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Purification, characterization and decolourization ability of Fomes Fomentarius laccase produced in solid medium
Journal of Molecular Catalysis B-enzymatic, 2010Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Semia Ellouze-chaabouniAbstract:Abstract Laccase produced by Fomes Fomentarius grown on wheat bran in solid cultures was purified to electrophoretic homogeneity by ammonium sulfate precipitation, size-exclusion chromatography and anion-exchange chromatography. A single laccase was found having apparent molecular mass of 51 kDa. The N-terminal amino acid sequence was IGPKTDLTIATGDVSPDG and the highest similarity value was found to the laccase from Trametes sp. 420 (94%). The enzyme exhibits a temperature optimum of 60 °C and has a half-life of 66 min at 60 °C. It manifested maximal activity at pH 4 and showed K m , k cat and k cat / K m values of 26 μM, 106 s −1 and 4 × 10 6 s −1 M −1 , respectively, with 2,6-dimethoxyphenol as substrate. The purified laccase was resistant to several metal ions such as Cd 2+ , Fe 2+ , Zn 2+ , Mg 2+ , Mn 2+ and Cu 2+ . In addition, the enzyme had ability to decolourize the anthraquinone dye Remazol Brilliant Blue R without mediators.
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Effect of culturing processes and copper addition on laccase production by the white-rot fungus Fomes Fomentarius MUCL 35117.
Letters in Applied Microbiology, 2009Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Semia Ellouze-chaabouni, Michel PenninckxAbstract:Aim: To produce high laccase activities from the white-rot fungus Fomes Fomentarius. Methods and Results: Different culturing methods, viz, cell immobilization on stainless steel sponges and plastic material and solid-state fermentation (SSF) using wheat bran as substrate were used for laccase production by the white-rot fungus F. Fomentarius. The SSF study expresses the highest laccase activities, nearly to 6400 U l−1 after 13 days of laboratory flasks cultivation. When the wheat bran medium was supplemented with 2 mmol l−1 copper sulfate, laccase activity increased by threefold in comparison to control cultures, reaching 27 864 U l−1. With the medium thus optimized, further experiments were performed in a 3 l fixed-bed bioreactor (working volume 1·5 l) leading to a laccase activity of about 6230 U l−1 on day 13. Conclusions: The results obtained clearly showed the superiority of wheat bran for laccase production over stainless steel sponges and plastic material. Supplementing the wheat bran solid medium with 2 mmol l−1 copper sulfate allowed obtaining high activities at flask scale. The system was scaled to fixed-bed laboratory reactor. Significance and Impact of the Study: The high enzyme production along with the low-cost of the substrate, showed the suitability of the system F. Fomentarius– SSF for industrial purposes.
Atef Jaouani - One of the best experts on this subject based on the ideXlab platform.
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doi:10.4061/2011/368525 Research Article Application of Asymetrical and Hoke Designs for Optimization of Laccase Production by the White-Rot Fungus Fomes Fomentarius in Solid-State Fermentation
2016Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Amel Kamoun, Semia Ellouze-chaabouniAbstract:Copyright © 2011 Mohamed Neifar et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Statistical approaches were employed for the optimization of different cultural parameters for the production of laccase by the white rot fungus Fomes Fomentarius MUCL 35117 in wheat bran-based solid medium. first, screening of production parameters was performed using an asymmetrical design 2533//16, and the variables with statistically significant effects on laccase production were identified. Second, inoculum size, CaCl2 concentration, CuSO4 concentration, and incubation time were selected for further optimization studies using a Hoke design. The application of the response surface methodology allows us to determine a set of optimal conditions (CaCl2, 5.5mg/gs, CuSO4, 2.5mg/gs, inoculum size, 3 fungal discs (6mmØ), and 13 days of static cultivation). Experiments carried out under these conditions led to a laccase production yield of 150U/g dry substrate. 1
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improving the nutritive value of olive cake by solid state cultivation of the medicinal mushroom Fomes Fomentarius
Chemosphere, 2013Co-Authors: Mohamed Neifar, Atef Jaouani, Amani Ayari, Olfa Abid, Hichem Ben Salem, Abdellatif Boudabous, Taha Najar, Raoudha Ellouze GhorbelAbstract:Abstract Olive Cake (OC) generated by the olive oil industries, well implanted in Tunisia, represents a major disposal and potentially severe pollution problem. This work presents the study of bioconversion of OC in solid state fermentation with the medicinal mushroom, Fomes Fomentarius so as to upgrade its nutritional values and digestibility for its use as ruminants feed. The fungus was cultured on OC for 7–30 d, and subsequently the chemical composition, lignocellulolytic enzyme activities and in vitro digestibility of the resultant substrate were determined. The results obtained showed an increase in the crude protein ranging from 6% to 22% for the control and for treated OC, respectively. Significant ( P in vitro digestibility improved from 9% (control) to 25% (treated OC). The present findings revealed F. Fomentarius to be an efficient organism for lignocellulolytic enzymes production and simultaneous enhancement in crude protein and in vitro digestibility of OC.
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Application of Asymetrical and Hoke Designs for Optimization of Laccase Production by the White-Rot Fungus Fomes Fomentarius in Solid-State Fermentation
Enzyme Research, 2011Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Amel Kamoun, Semia Ellouze-chaabouniAbstract:Statistical approaches were employed for the optimization of different cultural parameters for the production of laccase by the white rot fungus Fomes Fomentarius MUCL 35117 in wheat bran-based solid medium. first, screening of production parameters was performed using an asymmetrical design 2533//16, and the variables with statistically significant effects on laccase production were identified. Second, inoculum size, CaCl2 concentration, CuSO4 concentration, and incubation time were selected for further optimization studies using a Hoke design. The application of the response surface methodology allows us to determine a set of optimal conditions (CaCl2, 5.5 mg/gs, CuSO4, 2.5 mg/gs, inoculum size, 3 fungal discs (6 mm O), and 13 days of static cultivation). Experiments carried out under these conditions led to a laccase production yield of 150 U/g dry substrate.
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Purification, characterization and decolourization ability of Fomes Fomentarius laccase produced in solid medium
Journal of Molecular Catalysis B-enzymatic, 2010Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Semia Ellouze-chaabouniAbstract:Abstract Laccase produced by Fomes Fomentarius grown on wheat bran in solid cultures was purified to electrophoretic homogeneity by ammonium sulfate precipitation, size-exclusion chromatography and anion-exchange chromatography. A single laccase was found having apparent molecular mass of 51 kDa. The N-terminal amino acid sequence was IGPKTDLTIATGDVSPDG and the highest similarity value was found to the laccase from Trametes sp. 420 (94%). The enzyme exhibits a temperature optimum of 60 °C and has a half-life of 66 min at 60 °C. It manifested maximal activity at pH 4 and showed K m , k cat and k cat / K m values of 26 μM, 106 s −1 and 4 × 10 6 s −1 M −1 , respectively, with 2,6-dimethoxyphenol as substrate. The purified laccase was resistant to several metal ions such as Cd 2+ , Fe 2+ , Zn 2+ , Mg 2+ , Mn 2+ and Cu 2+ . In addition, the enzyme had ability to decolourize the anthraquinone dye Remazol Brilliant Blue R without mediators.
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Effect of culturing processes and copper addition on laccase production by the white-rot fungus Fomes Fomentarius MUCL 35117.
Letters in Applied Microbiology, 2009Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Semia Ellouze-chaabouni, Michel PenninckxAbstract:Aim: To produce high laccase activities from the white-rot fungus Fomes Fomentarius. Methods and Results: Different culturing methods, viz, cell immobilization on stainless steel sponges and plastic material and solid-state fermentation (SSF) using wheat bran as substrate were used for laccase production by the white-rot fungus F. Fomentarius. The SSF study expresses the highest laccase activities, nearly to 6400 U l−1 after 13 days of laboratory flasks cultivation. When the wheat bran medium was supplemented with 2 mmol l−1 copper sulfate, laccase activity increased by threefold in comparison to control cultures, reaching 27 864 U l−1. With the medium thus optimized, further experiments were performed in a 3 l fixed-bed bioreactor (working volume 1·5 l) leading to a laccase activity of about 6230 U l−1 on day 13. Conclusions: The results obtained clearly showed the superiority of wheat bran for laccase production over stainless steel sponges and plastic material. Supplementing the wheat bran solid medium with 2 mmol l−1 copper sulfate allowed obtaining high activities at flask scale. The system was scaled to fixed-bed laboratory reactor. Significance and Impact of the Study: The high enzyme production along with the low-cost of the substrate, showed the suitability of the system F. Fomentarius– SSF for industrial purposes.
Petr Baldrian - One of the best experts on this subject based on the ideXlab platform.
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Extracellular Enzymes of the White-Rot Fungus Fomes Fomentarius and Purification of 1,4-β-Glucosidase
Applied Biochemistry and Biotechnology, 2012Co-Authors: Tomáš Větrovský, Petr Baldrian, Jiří GabrielAbstract:Production of the lignocellulose-degrading enzymes endo-1,4-β-glucanase, 1,4-β-glucosidase, cellobiohydrolase, endo-1,4-β-xylanase, 1,4-β-xylosidase, Mn peroxidase, and laccase was characterized in a common wood-rotting fungus Fomes Fomentarius, a species able to efficiently decompose dead wood, and compared to the production in eight other fungal species. The main aim of this study was to characterize the 1,4-β-glucosidase produced by F. Fomentarius that was produced in high quantities in liquid stationary culture (25.9 U ml−1), at least threefold compared to other saprotrophic basidiomycetes, such as Rhodocollybia butyracea, Hypholoma fasciculare, Irpex lacteus, Fomitopsis pinicola, Pleurotus ostreatus, Piptoporus betulinus, and Gymnopus sp. (between 0.7 and 7.9 U ml−1). The 1,4-β-glucosidase enzyme was purified to electrophoretic homogeneity by both anion-exchange and size-exclusion chromatography. A single 1,4-β-glucosidase was found to have an apparent molecular mass of 58 kDa and a pI of 6.7. The enzyme exhibited high thermotolerance with an optimum temperature of 60 °C. Maximal activity was found in the pH range of 4.5–5.0, and KM and Vmax values were 62 μM and 15.8 μmol min−1 l−1, respectively, when p-nitrophenylglucoside was used as a substrate. The enzyme was competitively inhibited by glucose with a Ki of 3.37 mM. The enzyme also acted on p-nitrophenylxyloside, p-nitrophenylcellobioside, p-nitrophenylgalactoside, and p-nitrophenylmannoside with optimal pH values of 6.0, 3.5, 5.0, and 4.0–6.0, respectively. The combination of relatively low molecular mass and low KM value make the 1,4-β-glucosidase a promising enzyme for biotechnological applications.
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Ecology of coarse wood decomposition by the saprotrophic fungus Fomes Fomentarius
Biodegradation, 2011Co-Authors: Tomáš Větrovský, Jana Voříšková, Jaroslav Šnajdr, Jiří Gabriel, Petr BaldrianAbstract:Saprotrophic wood-inhabiting basidiomycetes are the most important decomposers of lignin and cellulose in dead wood and as such they attracted considerable attention. The aims of this work were to quantify the activity and spatial distribution of extracellular enzymes in coarse wood colonised by the white-rot basidiomycete Fomes Fomentarius and in adjacent fruitbodies of the fungus and to analyse the diversity of the fungal and bacterial community in a fungus-colonised wood and its potential effect on enzyme production by F. Fomentarius . Fungus-colonised wood and fruitbodies were collected in low management intensity forests in the Czech Republic. There were significant differences in enzyme production by F. Fomentarius between Betula pendula and Fagus sylvatica wood, the activity of cellulose and xylan-degrading enzymes was significantly higher in beech wood than in birch wood. Spatial analysis of a sample B. pendula log segment proved that F. Fomentarius was the single fungal representative found in the log. There was a high level of spatial variability in the amount of fungal biomass detected, but no effects on enzyme activities were observed. Samples from the fruiting body showed high β-glucosidase and chitinase activities compared to wood samples. Significantly higher levels of xylanase and cellobiohydrolase were found in samples located near the fruitbody (proximal), and higher laccase and Mn-peroxidase activities were found in the distal ones. The microbial community in wood was dominated by the fungus (fungal to bacterial DNA ratio of 62-111). Bacterial abundance composition was lower in proximal than distal parts of wood by a factor of 24. These results show a significant level of spatial heterogeneity in coarse wood. One of the explanations may be the successive colonization of wood by the fungus: due to differential enzyme production, the rates of biodegradation of coarse wood are also spatially inhomogeneous.
Paul Boutié - One of the best experts on this subject based on the ideXlab platform.
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Histoire des utilisations thérapeutiques de l'amadouvier, Fomes Fomentarius (L. : Fr.) Fr.
Revue d'Histoire de la Pharmacie, 2002Co-Authors: Bertrand Roussel, Sylvie Rapior, Colette Charlot, Christian-louis Masson, Paul BoutiéAbstract:Cet article est une presentation des principales utilisations therapeutiques de Fomes Fomentarius (L. : Fr.) Fr, l'amadouvier. La trame de ce champignon est une matiere douce et cotonneuse nommee amadou. Elle etait utilisee aux XVIIIe et XIXe siecles pour realiser des pansements hemostatiques. Elle servit egalement, sous forme de plaques, pour conserver la chaleur ou pour comprimer certaines parties du corps et, sous forme de cautere, dans le cadre de la moxibustion. Son role dans differentes pharmacopees traditionnelles (hongroise, chinoise, indienne) est egalement evoque.
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Histoire des utilisations thérapeutiques de l’amadouvier, Fomes Fomentarius (L.:Fr.) Fr.
Revue d'histoire de la pharmacie, 2002Co-Authors: Bertrand Roussel, Sylvie Rapior, Colette Charlot, Christian-louis Masson, Paul BoutiéAbstract:Cet article est une présentation des principales utilisations thérapeutiques de Fomes Fomentarius (L. : Fr.) Fr, l'amadouvier. La trame de ce champignon est une matière douce et cotonneuse nommée amadou. Elle était utilisée aux XVIIIe et XIXe siècles pour réaliser des pansements hémostatiques. Elle servit également, sous forme de plaques, pour conserver la chaleur ou pour comprimer certaines parties du corps et, sous forme de cautère, dans le cadre de la moxibustion. Son rôle dans différentes pharmacopées traditionnelles (hongroise, chinoise, indienne) est également évoqué.
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Fomes Fomentarius (L.:Fr.) Fr. : un champignon aux multiples usages
Cryptogamie Mycologie, 2002Co-Authors: Bertrand Roussel, Sylvie Rapior, Christian-louis Masson, Paul BoutiéAbstract:Cet article propose une présentation des usages de Fomes Fomentarius (amadouvier) à travers l'histoire. Ce polypore a en effet été utilisé par l'homme depuis la préhistoire et au moins jusqu'à la première guerre mondiale. Sa trame (ou context) est une matière douce et cotonneuse bien connue sous le nom d'amadou. Après une description du champignon, les auteurs s'attachent à inventorier ses utilisations traditionnelles (production du feu, utilisations médicales, fabrication de vêtements et d'articles pour la pêche) ainsi que quelques usages plus marginaux avant de présenter les aspects symboliques et légendaires de l'amadouvier. L'expérimentation de certaines des techniques présentées: production du feu et fabrication de tissu en amadou, a permis de mieux interpréter les sources et d'évaluer l'efficacité de ces techniques. Les nombreuses utilisations de F. Fomentarius montrent qu'il se situe au coeur des activités et des besoins de l'homme depuis l'époque préhistorique jusqu'à un passé proche.
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Fomes Fomentarius l fr fr un champignon aux multiples usages
Cryptogamie Mycologie, 2002Co-Authors: Bertrand Roussel, Sylvie Rapior, Christian-louis Masson, Paul BoutiéAbstract:Cet article propose une presentation des usages de Fomes Fomentarius (amadouvier) a travers l'histoire. Ce polypore a en effet ete utilise par l'homme depuis la prehistoire et au moins jusqu'a la premiere guerre mondiale. Sa trame (ou context) est une matiere douce et cotonneuse bien connue sous le nom d'amadou. Apres une description du champignon, les auteurs s'attachent a inventorier ses utilisations traditionnelles (production du feu, utilisations medicales, fabrication de vetements et d'articles pour la peche) ainsi que quelques usages plus marginaux avant de presenter les aspects symboliques et legendaires de l'amadouvier. L'experimentation de certaines des techniques presentees: production du feu et fabrication de tissu en amadou, a permis de mieux interpreter les sources et d'evaluer l'efficacite de ces techniques. Les nombreuses utilisations de F. Fomentarius montrent qu'il se situe au coeur des activites et des besoins de l'homme depuis l'epoque prehistorique jusqu'a un passe proche.
Semia Ellouze-chaabouni - One of the best experts on this subject based on the ideXlab platform.
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doi:10.4061/2011/368525 Research Article Application of Asymetrical and Hoke Designs for Optimization of Laccase Production by the White-Rot Fungus Fomes Fomentarius in Solid-State Fermentation
2016Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Amel Kamoun, Semia Ellouze-chaabouniAbstract:Copyright © 2011 Mohamed Neifar et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Statistical approaches were employed for the optimization of different cultural parameters for the production of laccase by the white rot fungus Fomes Fomentarius MUCL 35117 in wheat bran-based solid medium. first, screening of production parameters was performed using an asymmetrical design 2533//16, and the variables with statistically significant effects on laccase production were identified. Second, inoculum size, CaCl2 concentration, CuSO4 concentration, and incubation time were selected for further optimization studies using a Hoke design. The application of the response surface methodology allows us to determine a set of optimal conditions (CaCl2, 5.5mg/gs, CuSO4, 2.5mg/gs, inoculum size, 3 fungal discs (6mmØ), and 13 days of static cultivation). Experiments carried out under these conditions led to a laccase production yield of 150U/g dry substrate. 1
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Application of Asymetrical and Hoke Designs for Optimization of Laccase Production by the White-Rot Fungus Fomes Fomentarius in Solid-State Fermentation
Enzyme Research, 2011Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Amel Kamoun, Semia Ellouze-chaabouniAbstract:Statistical approaches were employed for the optimization of different cultural parameters for the production of laccase by the white rot fungus Fomes Fomentarius MUCL 35117 in wheat bran-based solid medium. first, screening of production parameters was performed using an asymmetrical design 2533//16, and the variables with statistically significant effects on laccase production were identified. Second, inoculum size, CaCl2 concentration, CuSO4 concentration, and incubation time were selected for further optimization studies using a Hoke design. The application of the response surface methodology allows us to determine a set of optimal conditions (CaCl2, 5.5 mg/gs, CuSO4, 2.5 mg/gs, inoculum size, 3 fungal discs (6 mm O), and 13 days of static cultivation). Experiments carried out under these conditions led to a laccase production yield of 150 U/g dry substrate.
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Purification, characterization and decolourization ability of Fomes Fomentarius laccase produced in solid medium
Journal of Molecular Catalysis B-enzymatic, 2010Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Semia Ellouze-chaabouniAbstract:Abstract Laccase produced by Fomes Fomentarius grown on wheat bran in solid cultures was purified to electrophoretic homogeneity by ammonium sulfate precipitation, size-exclusion chromatography and anion-exchange chromatography. A single laccase was found having apparent molecular mass of 51 kDa. The N-terminal amino acid sequence was IGPKTDLTIATGDVSPDG and the highest similarity value was found to the laccase from Trametes sp. 420 (94%). The enzyme exhibits a temperature optimum of 60 °C and has a half-life of 66 min at 60 °C. It manifested maximal activity at pH 4 and showed K m , k cat and k cat / K m values of 26 μM, 106 s −1 and 4 × 10 6 s −1 M −1 , respectively, with 2,6-dimethoxyphenol as substrate. The purified laccase was resistant to several metal ions such as Cd 2+ , Fe 2+ , Zn 2+ , Mg 2+ , Mn 2+ and Cu 2+ . In addition, the enzyme had ability to decolourize the anthraquinone dye Remazol Brilliant Blue R without mediators.
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Effect of culturing processes and copper addition on laccase production by the white-rot fungus Fomes Fomentarius MUCL 35117.
Letters in Applied Microbiology, 2009Co-Authors: Mohamed Neifar, Atef Jaouani, Raoudha Ellouze-ghorbel, Semia Ellouze-chaabouni, Michel PenninckxAbstract:Aim: To produce high laccase activities from the white-rot fungus Fomes Fomentarius. Methods and Results: Different culturing methods, viz, cell immobilization on stainless steel sponges and plastic material and solid-state fermentation (SSF) using wheat bran as substrate were used for laccase production by the white-rot fungus F. Fomentarius. The SSF study expresses the highest laccase activities, nearly to 6400 U l−1 after 13 days of laboratory flasks cultivation. When the wheat bran medium was supplemented with 2 mmol l−1 copper sulfate, laccase activity increased by threefold in comparison to control cultures, reaching 27 864 U l−1. With the medium thus optimized, further experiments were performed in a 3 l fixed-bed bioreactor (working volume 1·5 l) leading to a laccase activity of about 6230 U l−1 on day 13. Conclusions: The results obtained clearly showed the superiority of wheat bran for laccase production over stainless steel sponges and plastic material. Supplementing the wheat bran solid medium with 2 mmol l−1 copper sulfate allowed obtaining high activities at flask scale. The system was scaled to fixed-bed laboratory reactor. Significance and Impact of the Study: The high enzyme production along with the low-cost of the substrate, showed the suitability of the system F. Fomentarius– SSF for industrial purposes.