Strain improvement and genetic characterization of Alternaria tenuissima FCBP-252 for hyper-active α-amylase

Production of extra cellular α–amylase enzyme by a filamentous fungus, Alternaria tenuissima was studied in solid-state fermentation (SSF) as well as submerged fermentation (SmF). The potential strain was successfully mutated by UV and ethyl methanesulfonate (EMS). High-level of α–amylase activity was obtained by the mutant At-Ch-5.6 (76.75 Units ml^-1) after chemical treatment followed by UV mutant At-UV-2.8 (63.12 Units ml^-1) which was significantly higher than parental A. tenuissima FCBP–252 (32 Units ml^-1). These mutants with high levels of activity were genetically characterized using RAPD-PCR. The expression pattern of mutants exhibited that the mutants were isogenic variants of parent strain and out-performance of the mutants could be attributed to change in genetic make up. This work represented the first report of strain improvement in Alternaria for hyper activity of α–amylase enzyme and suggested that this fungus could be used to extract purified enzyme.