Abstract

Pure culture of wild type of Aspergillus niger was subjected to gamma rays mutagenesis at different dose rates (40 to 120 k.Rads). The mutant strains of Aspergillus niger were isolated and selected by random screening method. The selected mutant derived strains were compared with parent type of Aspergillus niger for enhanced production potential of mutarotase. A mutant strain of Aspergillus niger with maximum production potential of mutarotase was finally selected. The enzyme activity of wild type strain was 4.33 U/mL whereas the mutant derived strain showed significantly higher enzyme activity (22.0 U/mL). It is concluded that gamma irradiation of Aspergillus niger can be used for hyperproduction of mutarotase for its ultimate use in clinical diagnostic kits.