STRAIN IMPROVEMENT OF ASPERGILLUS NIGER FOR GLUCOAMYLASE BY PHYSICAL AND CHEMICALMUTAGENS

Abstract

The purpose of present investigation is to enhance Glucoamylase production by subjecting Aspergillusniger to strain improvement by random mutagenesis using UltraViolet (UV) irradiation, Ethyl Methyl Sulphonate (EMS) and Ethidium bromide treatment. mutants were screened on the basis of enzyme assay by spectrophotometer using Dinitrosalicylicacid reagent (DNS).UV-18 mutant produced 18.11 U/ml/min, EMS-4 mutant produced 14.93 U/ml/min, Ethidiumbromide-13 mutant produced 18.31U/ml/min and EMS&EB-18 mutant produced 18.84 U/ml/min glucoamylase, compare to wild strains UV-18,EMS-4,EB-13 and EMS&EB-18 mutant strains were found to produce 2-4 fold more enzyme .thus these findings have more impact on enzyme economy for biotechnological applications of microbial amylases .