The potential of agro-industrial residues for production of holocellulase from filamentous fungi

Abstract

Fungal species, including Aspergillus oryzae, Aspergillus terreus, Emericella nidulans, Penicillium citrinum, Fusarium verticillioides, Fusarium proliferatum and Paecilomyces lilacinum, were isolated from cotton processing residues. They were screened for their ability to produce holocellulases when grown in liquid-state media containing agro-industrial residues as the carbon sources. Experiments on the growth of filamentous fungi on culture media containing cotton residue as the carbon source is reported for the first time. For convenience, cultivation conditions (other than temperature) and enzyme assays were the same for all fungi, i.e., no attempt at optimization of individual was made. The objective of this work was to identify fungi and holocellulase (cellulase, hemicellulase and pectinase) of academic interest and as well as of potential commercial application. The pattern of holocellulase production was influenced by the type of agro-industrial residue present in the medium. The best yields of holocellulases were obtained from extracts of A. oryzae and A. terreus. Enzyme multiplicity was evidenced by fractionation of the crude extracts on ultrafiltration, gel filtration and ion-exchange chromatography procedures and zymogram analysis.