Avicel-adsorbable endoglucanase production by the thermophilic fungus Scytalidium thermophilum type culture Torula thermophila

Scytalidium thermophilum type culture Torula thermophila was isolated from mushroom compost and the total cellulase, endoglucanase, Avicel-adsorbable endoglucanase activities, as well as the fungal biomass generation and cellulose utilisation were analyzed in shake flask cultures with Avicel (microcrystalline cellulose) as the carbon source. Results were compared with an industrial strain of Scytalidium thermophilum type culture Humicola insolens. The pH and temperature optima for endoglucanase activities during enzyme assays were also analyzed for both organisms and determined to be pH 6.0 and 65°C for type culture Torula thermophila, and pH 6.5 and 60°C for type culture Humicola insolens. Analysis of the effect of growth temperature showed that type culture T. thermophila can grow and produce cellulases in the range of 35 to 55°C although 40 to 50°C seemed to favor growth and cellulase production. Although 45°C was found optimal for fungal growth, both the specific endoglucanase and Avicel-adsorbable endoglucanase activities (U/mg protein) as well as the percentage of Avicel-adsorbable endoglucanase activity reached maxima at 50°C and were higher as compared to type culture H. insolens. Results indicate that type culture T. thermophila, with further optimisations, is of potential use in the industrial production of cellulases.