Development of an industrial medium and a novel fed-batch strategy for high-level expression of recombinant β-mananase by Pichia pastoris

► A novel industrial medium was developed for high-density fermentation of Pichia pastoris. ► A fed-batch strategy combining the real-time exponential feed and DO-stat feed mode was developed. ► The high-level expression of β-mananase was obtained in a 50-L fermenter.