Microbial cellulase: production and application in enzymatic treatment of biosolids

Abstract

One of the main objectives in the treatment of biosolids is to reduce the cellulolytic materials which represent 40 to 50% of the total dry weight. Cellulose degradation is initiated primarily by micro-organism (fungi, bacteria and protozoa) with the aid of extracellular enzymes. The cellulase(s) is a multiple enzyme system consisting of endoglucanase, exoglucanase and β-glucosidase which act as a synergistic effect for the degradation of complex cellulose to glucose. Cellulase enzyme has applied for several industrial activities including production of animal feed, and wine, formulation of detergents, juice clarification, as well as in the treatment of domestic and industrial wastes. The enzymatic treatment of biosolids is named white technology which has raised recently due to the efficiency and absence of toxic by-products. In this chapter the factors affecting production of cellulase enzyme by microorganisms, the potential of indigenous microorganisms for the bio-augmentation process of biosolids and occurrence of catabolite repression phenomenon of cellulase production during the enzymatic degradation of biosolids will be discussed.