Repeated fed-batch process for improving lovastatin production

Submerged cultivation of a high yielding strain of Aspergillus terreus DRCC 122 for the production of lovastatin in the batch process had limited success with a maximum titre of 1270 mg l(-1) in 288 h and an overall volumetric productivity of 4.41 mg l(-1) h(-1) in a 10001 bioreactor. A cost effective repeated fed-batch process with maltodextrin and corn steep liquor feed as carbon and nitrogen sources, respectively, showed a significant increase in lovastatin yield. The final titre was 2200 mg l(-1) in 288 h of fermentation, with overall volumetric productivity of 7.64 mg l(-1) h(-1), showing an increase of 73% over the batch process. The kinetic parameters were studied; maximum specific oxygen uptake rate (Q(O2)) and volumetric mass transfer coefficient (K(L)a) were 0.24 m mole O-2 g(-1) dry cell wt. h(-1) and 280 h(-1), respectively, in fed-batch process. (C) 2000 Elsevier Science Ltd. All rights reserved.