Abstract
The fermentation conditions such as nitrogen source, corn steep liquor, yeast extract and cane molasses were optimized for aamylase production. Aspergillus niger produced maximum alpha-amylase (21.20 IU/ml/min) in the optimum growth medium of waste bread (1.5%), containing 0.2% (NH4hS04, 1.0% corn steep liquor, 0.10% yeast extract and 1.0% cane molasses (added after 12 hr). (NH4hS04 proved to be the best additional nitrogen source amongst urea, NH4H2P04 and NaNOJ• Alphaamylase produced under optimum conditions was partially purified and maximally isolated by 50% (NH4hS04 precipitation. Specific activity of the enzyme increased by 7.19 folds after (NH4hS04 precipitation. Key words: alpha-amylase, Aspergillus niger, partial purification, waste bread
