Kinetic Study and Characterization of Cellulase Enzyme from Isolated <em>Aspergillus niger subsp. awamori</em> for Cellulosic Biofuels

Abstract

In the present study, a cellulase producing <em>Aspergillus </em> species was isolated from wood chips and was identified as <em>Aspergillus niger subsp. awamori</em> (also called <em>A. awamori</em>) using 18s rRNA sequencing (Genbank Accession number KP164968). The enzyme was purified to 42.5 fold by gel filtration chromatography and the molecular mass of the enzyme was determined as 66±1 kDa using SDS-PAGE. The purified enzyme showed an optimum temperature of 50°C and pH 5. Metal ions such as Ca²⁺, Mg²⁺, Zn²⁺, Pb²⁺, Fe²⁺ and Fe³⁺ had positive influence on the enzyme activity. The K_M and V_max for the enzyme was found to be 0.011g and 0.1098U/ml respectively. The addition of this cellulase to lignocellulosic biomass showed good degradation of cellulose and therefore this fungus could be a future source for production of bioethanol from Lignocellulosic Biomass (LB).