Novel Sources of Fungal Cellulases for Efficient Deinking of Composite Paper Waste

Twenty thermophilic/thermotolerant fungal strains were isolated from compositing soils and screened for production of different enzymes (Endoglucanases, β-glucosidase, Fpase and xylanases) to assess their deinking efficiency. Three isolates, Aspergillus sp. AMA, Aspergillus terreus AN1, and Myceliophthora fergusii T4I, identified on the basis of morphological and sequencing of amplified ITS1-5.8S-ITS2 rDNA region, showed significant deinking of composite waste paper (70% magazine and 30% Xerox copier/ laser print paper waste) as well as improved properties (brightness, tensile strength, tear index) of recycled paper sheets. The chosen strains Aspergillus sp. AMA, Aspergillus terreus AN1 and Myceliophthora fergusii T4I, showed 53, 52.7, and 40.32% deinking with increase in brightness by 4.32, 3.56, and 3.01 % ISO, respectively. These cultures were found to produce multiple endoglucanases and were characterized to lack a cellulose binding module (CBD), which may be responsible for their better deinking efficiency.