Medium optimization for glucoamylase production by a yeast, Pichia subpelliculosa ABWF-64, in submerged cultivation

An amylolytic yeast strain Pichia subpelliculosa was shown to produce glucoamylase in submerged cultivation. The yeast strain produced the enzyme optimally at 30 degreesC and pH 5.6 in shake flasks agitated at 200 rev min(-1) in the optimized glucoamylase production medium containing 1% starch, 0.2% yeast extract, 0.4% K2HPO4, 0.035% NaCl and 0.1% MgCl2. Maximum enzyme production was attained during early growth of 11 h in shake flasks, and 6 h in a laboratory fermenter. By optimizing media components and cultivation parameters, a 15-fold increase in glucoamylase secretion was achieved.