Evaluation of methods for screening of extracellular cellulase In filamentous fungi

Abstract

Twenty-eight fungal species belonging to fifteen genera were isolated from Saudi Arabian soil and were screened for the production of extracellular cellulase enzymes. Cleared-zone technique, cellulose azure method and agar diffusion test for rapid screening were used. The cleared-zone technique was found to be much less reliable as compared to other methods. Trichoderma viride, T. pseudokoningii and Aspergillus fumigatus were the best producers of cellulase enzyme. The data obtained also suggest that caution is needed using these methods. The disadvantages of using one method for screening, which has been a common practise up to now, are discussed.