OPTIMIZATION OF CULTURAL CONDITIONS FOR THE PRODUCTION OF ALPHA AMYLASE BY WILD AND MUTANT STRAIN OF ASPERGILLUS ORYZAE IN STIRRED FERMENTER

The present study deals the optimization of cultural conditions for the production of alpha amylase by Aspergillus oryzae IIB-30 and its mutant derivative A. oryzae EMS-18 in stirred fermenter. The time of fermentation for enzyme production by both wild and mutant strains was studied. It was found that the time required for maximal enzyme production (608 U/ml) in case of mutant strain was reduced to 48 h compared with 64 h by wild strain for maximum enzyme production (335 U/ml). The kinetic depiction of results showed optimal fermentation period for enzyme production to be 64 h and 48 h, respectively. The other cultural conditions such as initial pH (5), aeration rate 1.5 vvm (mutant), dissolved oxygen (15%), inoculum size (10%) and agitation intensity (200 rpm) were optimized for enzyme production.