Production of Cellulolytic Enzymes on Agricultural Waste by Different Zygomycetes

Filamentous fungi are good producers of different extracellular enzymes. Due to this feature, some of them assumed to play an important role in the decomposition of plant and other organic materials. Several members of the class Zygomycetes are involved in different biotechnological applications, in consequence of their efficient extracellular enzyme production. Because of the increasing interest in the microbial biodegradation, isolates of Mucor corticolus (syn.: M. circinelloides f. corticolus) and Gilbertella persicaria were screened for their secreted cellobiohydrolase (1,4-β-D-glucan cellobiohydrolase) and beta-glucosidase activities. These enzymes are key-players in the microbiological degradation of cellulose biomass. The aim of the present study was to evaluate the production of these cellulolytic enzymes on a cheap, exploitable agricultural waste. To investigate the production of cellobiohydrolase and beta-glucosidase, solid-state fermentations were performed on chopped corn-stalks and corn leaves as carbon source. Cultures incubated at 25°C for 12 days were repeatedly sampled to monitor changes in the enzyme activities. Results show that isolates of both species showed intensive growth on these substrates, and high activities of the investigated enzymes were observed during the fermentation period. The potential application of these fungi for biodegradation and enzyme production is discussed.