The Relation of Oxidation-Reduction Potential to the Growth of an Aerobic Microorganism

Abstract
Growth of Bacillus megatherium in the presence of sufficient oxygen is influenced by the oxidation-reduction conditions of the culture medium. The oxidized form of oxidation-reduction indicators more positive than methylene blue inhibits growth in a beef-extract broth. Potentiometric measurements indicate that the inhibition was due to the poising of the medium at too oxidized a potential. The addition of K2SO3 in suitable amts. improved the beef-extract broth for growth initiation.