Three vegetable residues from the palm oil industry were used as substrate for
cultivation of different white rot fungi strains (basidiomycetes). The growth and
production of lignocellulolytic enzymes were evaluated by solid and submerged
fermentation. The enzymatic extracts obtained from fermentations were used in
enzymatic hydrolysis process of pretreated sugarcane bagasse and oil palm empty
bunch. Fifty-four macrofungal strains were cultivated in three formulations of oil palm
biomass on Petri dishes, where 5 strains with faster and dense growth were chosen.
These five macrofungal strains were cultivated in solid state fermentation and
evaluated by the enzymatic activities of the extracts obtained. In these extracts,
activities of laccase, peroxidase, manganese peroxidase and protease were found to
be predominant. Three of the five strains were selected with predominance in oxidative
activities on solid state fermentation cultures to be evaluated in submerged
fermentation (monocultures) using synthetic medium supplemented with oil palm
biomass. The enzymatic activities of the three basidiomycetes srtains were compared
with five fungal strains frequently used in the literature. There were significant
differences in function of the oxidative activities (laccase and peroxidases) and
hydrolytic activities (PFase and β-glucosidases) among the tested strains. These
differences were used to establish subgroups which were evaluated through the
interaction in plates and cocultures in submerged fermentation. The enzymatic
activities of the extracts obtained from monocultures and cocultures presented
differences, with predominantly positive interactions between the three basidiomycetes
and T. reesei ATCC® 60787. Monocultures and cocultures were compared as a
function of the glucose release after the enzymatic hydrolysis of sugarcane bagasse
pretreated by autohydrolysis. The enzymatic hydrolysis of the coculture extracts
obtained higher percentages (maximum value 44.7%) when compared to
monocultures. An analysis of simplex lattice mixtures was made using the monoculture
extracts as components to obtain an enzymatic cocktail in order to optimize the glucose
release of the pretreated sugarcane bagasse. The results showed that extracts with
higher hydrolytic activities are correlated with the higher glucose release and extracts
with oxidative enzymes can improve the sugar yield, thus having a mixture or cocktail
characterized by hydrolytic and oxidative enzymes with the potential to obtain sugars. Finally, this cocktail was used in the hydrolysis of untreated, physically, biologically and
biologically-physically (combined) pretreated oil palm empty bunch, obtaining a
maximum yield of 11.8 gL-1 of glucose in the biomass of palm oil when pretreated
biological-physically, which corresponded between 40-60% of the yield of the
commercial enzymes Cellic® Ctec3 and Cellic® Ctec2.
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