Cellulases are a complex group of enzymes which are secreted by a broad range of microorganisms including fungi, bacteria, and actinomycetes. In the natural environment, synergistic interactions among cellulolytic microorganisms play an important role in the hydrolysis of lignocellulosic polymer materials. In fact, it is the combined action of three major enzymes which determines the efficiency of this process. They are exoglucanases, endoglucanases, and β-glucosidase. Microorganisms produce these enzymes in a diverse nature which determines their efficiency in cellulose hydrolysis. During the cellulose degradation reaction, the enzyme targets the β-1,4-linkages in its polymeric structure. This is an essential ecological process as it recycles cellulose in the biosphere. The application of this same scenario for industrial purposes is identified as an emerging area of research. Biofuel production, textile polishing and finishing, paper and pulp industry, and lifestyle agriculture are among the key areas where cellulase enzyme shows a broader potential. The objective of this chapter is to discuss the structure, function, possible applications, as well as novel biotechnological trends of cellulase enzymes. Furthermore, possible low-cost, enzymatic pretreatment methods of lignocellulosic material in order to use it as an efficient raw material for biofuel production will be discussed.

This study intended to compare the efficiency of fungal monocultures and co-cultures in the simultaneous delignification and saccharification of kitchen waste and Eichhornia crassipes in order to subject the hydrolysate into biofuel production. Three fungal isolates of genus Trichoderma, Aspergillus, Pycnoporus and an unidentified strain (F113) were grown in mono and co-cultures and the extracted enzymes were used for the degradation. Co-culture of Trichoderma spp with the other fungi improved its enzyme activity while the other co-cultures did not show significantly improved enzymatic degradation compared to monocultures. The highest percentage of saccharification (over total dry weight) achieved were 11.9% with kitchen waste after seven days and 9.8% with E. crassipes after 4 days. The drop in degradation rate normally seen after complete digestion of amorphous cellulose was not apparent probably due to the grinding of the substrates to fine particle size.