Studies were conducted on the production of leucine amino peptidase (LAP) by Streptomyces gedanensis to ascertain the performance of the process in shake flask, parallel fermenter and 5-L fermenter utilizing soy bean meal as the carbon source. Experiments were conducted to analyze the effects of aeration and agitation rate on cell growth and LAP production. The results unveiled that an agitation rate of 300 rpm, 50% dissolved oxygen (DO) upholding and 0.15 vvm strategies were the optimal for the enzyme production, yielding 22.72 +/- 0.11 IU/mL LAP in parallel fermenter which was comparable to flask level (24.65 +/- 0.12 IU/mL LAP) fermentation. Further scale-up, in 5-L fermenter showed 50% DO and 1 vvm aeration rate was the best, producing optimum and the production was 20.09 +/- 0.06 IU/mL LAP. The information obtained could be useful to design a strategy to improve a large-scale bioreactor cultivation of cells and production of LAP. (C) 2011 Elsevier Ltd. All rights reserved.