A detailed description of the microbial glycoside hydrolases able to degrade
lignocellulosic biomass is very important for a better understanding of the new
processes involving biorefinery - the conversion of biomass into biofuels. Cellulose
and hemicellulose, the major carbohydrates of plant biomass, together with lignin,
constitute the most abundant organic compounds present in nature. Cellulose and
hemicellulose are converted enzymatically into glucose, xylose or other sugars, which
may be fermented by yeasts into second-generation bioethanol or other chemicals. In
order to process the lignocellulosic biomass in biorefinery, the use of efficient
degrading enzymes is essential for the bioconversion. In this chapter, we describe recent
advances in the characterization of glycoside hydrolases, auxiliary activities and
synergism between cellulases and accessory proteins involved in cellulose hydrolysis.
Furthermore, considering that pretreatments are necessary for efficient biomass
degradation and exposition of the lignocellulosic components, a detailed description of
several physical, chemical, physicochemical, biological and integrated pretreatments is
also presented. Modern and classical methods, including spectroscopy, coupled
chromatography, electron microscopy, MALDI- imaging MS, and others, are also
discussed as strategies for improving both fiber characterization and understanding of
the saccharification of lignocellulose and subsequent biofuel production.
Keywords: Biomass, biorefinary, cellulases, filamentous fungi, ligninases,
pretreatment, prospecting, xylanases.
