EFFECT OF DISSOLVED OXYGEN LEVEL ON B. SUBTILIS SPORE CULTIVATION DURING SUBMERGED FERMENTATION IN BIOREACTOR

Abstract

 This paper presents research findings on the impact of dissolved oxygen levels on the spore formation of B. subtilis during submerged cultivation in a bioreactor. The experiments analyzed both static and dynamic oxygen levels. The study revealed that oxygenation changes significantly affect the kinetics and yield of B. subtilis spores. When static DO values ranged from 0% to 50%, the process proved economically inefficient, with either non-viable bacteria at the end of the cycle or a spore yield that was not cost-effective. Conversely, DO levels from 50% to 0% resulted in rapid spore formation, followed by a shift from sporulation form back to vegetative form.

The research identified the optimal dissolved oxygen range for cultivation as a dynamic cycle between 0% and 50%, where sporulation occurred after 36 hours, with spores comprising 95% of the total bacterial mass. This study broadens our understanding of biotechnological growth factors in bioreactor systems.

Microbiological and biotechnological methods were used for submerged cultivation in bioreactors, along with physicochemical monitoring of dissolved oxygen.

The practical relevance of this study lies in its potential application in controlling the cultivation of this microorganism for industrial biotechnological processes.