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Although a number of filamentous fungi, such as Trichoderma and Aspergillus, are well known as producers of cellulases, xylanases, and accessory cellulolytic enzymes, the search for new strains and new enzymes has become a priority with the increase in diversity of biomass sources. Moreover, according to the type of pretreatment applied, biomass of the same type may require different enzyme blends to be efficiently hydrolyzed. This study evaluated cellulases, xylanases, and beta-glucosidases produced by two fungi, the thermotolerant Acrophialophora nainiana and Ceratocystis paradoxa. Cells were grown in submerged culture on three carbon sources: lactose, wheat bran, or steam-pretreated sugarcane bagasse, a commonly used cattle feed in Brazil. Xylanase and endo-1-4-beta-glucanase (CMCase) highest production were found in A. nainiana growing on lactose and reached levels of 2,200 and 2,016 IU/L, respectively. C. paradoxa showed highest activity for xylanase when grown on wheat bran and for beta-glucosidase when grown on steam-treated bagasse, at levels of 12,728 and 1,068 IU/mL, respectively.

Aiming to decrease the cost of enzymes used to hydrolyze biomass, the liquid stream from the hotcompressed water (HCW) treatment of sugarcane bagasse was used in the growth medium of Aspergillus awamori 2B.361 U2/1. Statistical experimental design was used to determine the HCW 1 temperature and residence time for maximum hemicellulose-derived sugar recovery to the liquid stream. The HCW reactor was fed with 10 % (w/v) bagasse, and the treatment was performed under agitation using an initial pressure of 20 bar (N 2 ) at 170°C for 40 min. The HCW liquid stream (23.70 ±0.

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