Characterization, optimization, and scale-up of cellulases production by Trichoderma reesei CBS 836.91 in solid-state fermentation using agro-industrial products

ORTIZ GE; GUITAR ME; CABALLITO SF; ALBERTÓ E.; FERNÁNDEZ-LAHORE M; BLASCO M.

BIOPROCESS AND BIOSYSTEMS ENGINEERING

SPRINGER

Lugar: Berlin; Año: 2015 vol. 38 p. 2117 - 2128

1615-7591

The appl ication of cellulases in sacc harificati on processe s is restricted by its produc tion cost. Conseque ntly, new funga l strains able to ela borate highe r cellulase s titers and with special activi ty profiles are require d to make the process econom ical. The aim of this investigati on was to find a promis ing wild-ty pe Tric hoderma strain for cellu-lases produc tion. The Tricho derma reesei strain 938 (CB S 836.91) was sel ected amo ng twenty strains on the basis of cellulase -agar-p late screeni ng. Ev aluation o f the selected strain on six solid substra tes indicated the highest activit ies to be obtained from whe at bran. Statis tical analyses of the experim ental design indicated a significa nt effect of pH and moistu re on the generation of endogl ucanase (EGA) and filter-p aper (FPA ) activit y. Furt hermore, a central-c om-posite design-b ased optim ization reve aled that pH values betwee n 6.4 and 6.6 and moist ure from 74 to 94 % were optim al for cellul ases produc tion. Unde r these conditions, 8?10 IU gds - 1of FPA and 15.6?17.8 IU gds - 1 of EGA were obta ined. In addition, cultivat ion in a rotating- drum reactor under optimal condi tions gave 8.2 IU gds - 1 FPA and 13.5 IU gds - 1 EGA . Biochemica l characteriza tion of T. reesei 938 cellulase s indicated a substant ially higher resistanc e to 4 mM Fe ? 2 and a slight ly grea ter tol erance to alkaline pH in comparison to Celluclast  . These results sugges t that T. reesei 938 could be a prom ising candi date for improv ed cellulases produc tion through direct-ev olu-tion strategi es.