Optimization of culture conditions (pH and temperature) for cellulase production by Trichoderma viride Using groundnut (Arachis hypogaea) shell as substrate.

Microbial cellulases are important group of enzymes which are used for the conversion of lignocellulosic biomass in to a variety of products in various industries. Agricultural residues are a great source of lignocellulosic biomass which is renewable, chiefly unexploited and inexpensive. Four (4) isolates of Trichoderma species were isolated from various sites within Ahmadu Bello University, Zaria environment. The isolates were screened for cellulase production and Trichoderma viride was recorded to have the highest clearance zone of (40mm), thus chosen for further studies. Groundnut shell pretreated with 0.25 N NaOH (Alkaline pretreatment) was used as the substrate for cellulase production. Temperature and pH of the fermentation medium were optimized and the optimum parameters were found to be temperature of 40oC and initial pH of 6.0. These optimum parameters were used for cellulase production and a maximum yield of 0.065 U/ml was obtained. Partial enzyme purification was carried out using solid ammonium sulphate and cellulase activity was found to increase from 0.065 U/ml for crude enzyme to 0.071 U/ml for the partially purified enzyme. The result of the study shows that T. viride isolated from the soil within the University environment can be used to produce cellulase using groundnut shell as substrate under the optimum conditions determined.