Potential use of soybean hulls and waste paper as supports in SSF for cellulase production by Aspergillus niger

Cellulase has by vast applications in the biofuel, pulp and paper, detergent and textile industries. The three components of the enzyme complex (endoglucanase, exoglucanase and β-glucosidase) can effectively depolymerize the cellulose chains in lignocellulosic substrate. Solid-state fermentation (SSF) by fungi is a preferable production route for cellulase because of its low cost, among other advantages. This work describes the cellulase production by Aspergillus niger NRRL3 grown on SSF. SSF was carried out on soybean hulls and waste paper as supports. The effect of the support on cellulase production was assessed under a completely randomized factorial design. The support-time interaction was significant for all the variables studied. Both materials were characterized in terms of water absorption index and critical humidity point. Samples of culture were analyzed with scanning electron microscopy (SEM) to study spores and fungal growth.