Maltotetraose Production Using Pseudomonas stutzeri Exo‐α‐Amylase in a Membrane Recycle Bioreactor

摘要

ABSTRACTFor a continuous process using maltotetraose (G4)‐forming amylase in a membrane recycle bioreactor (MRB), the enzyme was partially purified to specific activity 21.5 IU/mg protein. The enzyme was stable enough to convert starch into G4in batch and MRB systems. Optimum conditions in the MRB using hollow fiber with 1,000 molecular weight cut‐off were: substrate concentration 1.0 (w/v), enzyme concentration 70 IU/L reactant, and residence time 83 min. Productivity at steady state under optimized conditions was 0.99 g/L/hr. Excessive residence time decreased product purity by further conversion of G4to lower molecular weight compounds due to endo‐acting activity of the e