title: Characterization, optimization, and scale-up of cellulases production by trichoderma reesei cbs 836.91 in solid-state fermentation using agro-industrial products.
abstract: The application of cellulases in saccharification processes is restricted by its production cost. Consequently, new fungal strains able to elaborate higher cellulases titers and with special activity profiles are required to make the process economical. The aim of this investigation was to find a promising wild-type Trichoderma strain for cellulases production. The Trichoderma reesei strain 938 (CBS 836.91) was selected among twenty strains on the basis of cellulase-agar-plate screening. Evaluation of the selected strain on six solid substrates indicated the highest activities to be obtained from wheat bran. Statistical analyses of the experimental design indicated a significant effect of pH and moisture on the generation of endoglucanase (EGA) and filter-paper (FPA) activity. Furthermore, a central-composite design-based optimization revealed that pH values between 6.4 and 6.6 and moisture from 74 to 94% were optimal for cellulases production. Under these conditions, 8-10 IU gds(-1) of FPA and 15.6-17.8 IU gds(-1) of EGA were obtained. In addition, cultivation in a rotating-drum reactor under optimal conditions gave 8.2 IU gds(-1) FPA and 13.5 IU gds(-1) EGA. Biochemical characterization of T. reesei 938 cellulases indicated a substantially higher resistance to 4 mM Fe(+2) and a slightly greater tolerance to alkaline pH in comparison to Celluclast(®). These results suggest that T. reesei 938 could be a promising candidate for improved cellulases production through direct-evolution strategies.
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico Chascomús (IIB-INTECH, UNSAM-CONICET), Universidad de San Martín, Av. 25 de Mayo y Francia, Campus UNSAM, 1650, San Martín, Buenos Aires, Argentina. gas.ortiz@gmail.com.|Downstream Processing Laboratory, Jacobs University Bremen, 28759, Bremen, Germany. gas.ortiz@gmail.com.
authors.forename: Gastón E
authors.initials: GE
authors.lastname: Ortiz
authors.affiliation: Downstream Processing Laboratory, Jacobs University Bremen, 28759, Bremen, Germany.|Institute of Chemistry and Biological Physicochemistry (IQUIFIB), School of Pharmacy and Biochemistry, University of Buenos Aires and National Research Council (CONICET), Junín 956, Buenos Aires, Argentina.
authors.forename: María E
authors.initials: ME
authors.lastname: Guitart
authors.affiliation: Research and Development Center for Industrial Fermentations (CINDEFI) (UNLP, CONICET La Plata), Calle 47 y 115, 1900, La Plata, Argentina.
authors.forename: Sebastián F
authors.initials: SF
authors.lastname: Cavalitto
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico Chascomús (IIB-INTECH, UNSAM-CONICET), Universidad de San Martín, Av. 25 de Mayo y Francia, Campus UNSAM, 1650, San Martín, Buenos Aires, Argentina.
authors.forename: Edgardo O
authors.initials: EO
authors.lastname: Albertó
authors.affiliation: Downstream Processing Laboratory, Jacobs University Bremen, 28759, Bremen, Germany.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Fernández-Lahore
authors.affiliation: Centro de Investigación y Desarrollo en Biotecnología Industrial, Instituto Nacional de Tecnología Industrial, Av. General Paz 5445, Edificio 51, San Martín, Buenos Aires, Argentina. mblasco@inti.gob.ar.
authors.forename: Martín
authors.initials: M
authors.lastname: Blasco
mesh_terms: D044602:Cellulases / Q000096:biosynthesis*; D004043:Dietary Fiber / Q000378:metabolism*; D005656:Fungal Proteins / Q000096:biosynthesis*; D014242:Trichoderma / Q000254:growth & development*
chemical_list: D004043:Dietary Fiber; D005656:Fungal Proteins; D044602:Cellulases
keywords: Cellulases production; Design of experiments; Drum bioreactor; Solid-state fermentation; Trichoderma reesei