Optimizing of the formation of active BMW-amylase after in vitro refolding

► The refolding condition of α-amylase from Bacillus megaterium WHO was optimized by RSM. ► 20% (v/v) glycerol, 25 mM Ca2+ and 0.3 (mg/ml) protein is the most efficient condition for refolding. ► Km and kcat value of refolded α-amylase with optimal conditions was much closer to soluble enzyme. ► DLS analysis indicated that optimized condition of refolding has generated more compact structure.