Investigation on the Production Kinetics of Lovastatin by Aspergillus terreus in a 5 L Fermentor

Using a 5 L fermentor, a comparatively low supplement of dissolved O2 (DO) almost stopped performing lovastatin synthesis using Aspergillus terreus. With the DO controlled at 20%, lovastatin production enhanced by 38% whereas biomass production decreased by 25% and sugar utilization increased by 18%, as compared with the shake-flask culture. However, manipulating the broth pH at 5.5, 6.5 or 7.5 starting from 48 h gave no benefit to product formation although biomass production was reduced largely. A pH-DO interaction was also found here, which significantly affected the fermentation response. In the study, we concluded that the enhancement of product formation closely depended upon the controls of culturing environments; meanwhile, the fungal morphology was also influenced by the fermmentation parameters and the interactions.