Influence of oxygen concentration on the metabolism of Penicillium chrysogenum

In large‐scale bioreactors, there is often insufficient mixing and as a consequence, cells experience uneven substrate and oxygen levels that influence product formation. In this study, the influence of dissolved oxygen (DO) gradients on the primary and secondary metabolism of a high producing industrial strain of Penicillium chrysogenum was investigated. Within a wide range of DO concentrations, obtained under chemostat conditions, we observed different responses from P. chrysogenum: (i) no influence on growth or penicillin production (>0.025 mmol L−1); (ii) reduced penicillin production, but no growth limitation (0.013–0.025 mmol L−1); and (iii) growth and penicillin production limitations (