Back to Contents

FREE FULL TEXT PDF

MUTAGENESIS OF BACILLUS LICHENIFORMIS THROUGH ETHYL METHANESULFONATE FOR ALPHA AMYLASE PRODUCTION

IKRAM-UL-HAQ, S. ALI, A. SALEEM AND M.M. JAVED

Abstract: The present study is concerned with the improvement of Bacillus licheniformis strain GCB-30^UCM for alpha amylase production in 250 ml Erlenmeyer flasks. Chemical mutation using ethyl methanesulfonate (EMS 50-300 µ/ml) was undertaken for 10-60 min. Twenty eight isolates were selected on the basis of clear zones of starch hydrolysis. Only one isolate designated as B. licheniformis EMS-200⁴⁰ gave 102.78±2.01 U/ml/min enzyme activity. The enzyme production was found to be maximal when fermentation medium containing (g/l) lactose 10.0, bactopeptone 14.0, yeast extract 6.0, KCl 1.0, CaCl₂ 0.25, MgCl₂ 0.2, MnSO₄ 0.001, FeSO₄ 0.0005, pH 6.5 was incubated at 37^oC for 72 h. The volume of medium (50 ml) and size of inoculum (4.0 %) were also optimized. The optimal enzyme activity was determined as a function of buffer pH (7.0) and temperature (60ºC).

Institute of Industrial Biotechnology (IIB), GC University Lahore, Pakistan