Effect of Various Physiological Parameters and Different Carbon Sources on Cellulase and Xylanase Induction by Different Strains of Trichoderma Species

Abstract

The recent interest in bioconversion of cellulosic wastes to value added chemicals has led to extensive studies onmicroorganisms capable of producing the enzyme. Cellulases are multi-enzyme complex proteins that catalyze theconversion of cellulose to glucose. Trichoderma is the main industrial source of cellulases and hemicellulases usedto depolymerize plant biomass to simple sugars that are converted to chemical intermediates such as biofuels. Thecurrent study was carried out to isolate and characterize different Trichoderma species for successful applications.The strains were characterized for cellulase and xylanase assays to determine their extracellular hydrolytic activities.Expression of xylanase was induced maximally by xylan and repressed by glucose. Moreover, a comparativeanalysis was done between two different Trichoderma species which revealed that Trichoderma harzianum andTrichoderma harzianum Th-azad shows better enzyme activity than T. viride 01PP. Furthermore, optimal conditionsfor enzyme activity and induction of enzyme synthesis were also determined. The results revealed that the optimalpH, temperature and incubation time for cellulase production was found to be 5.5, 28° C and 120 h respectively. Inthe present study, we also evaluate the effects of wheat bran, cellulose powder as carbon sources for cellulase andxylanase production. The result showed that the enzyme production was highest with wheat bran as sole source ofcarbon.