Optimisation of downstream processing parameters for the recovery of pectinase from the fermented bran of Aspergillus carbonarius

Aspergillus carbonarius produces extracellular pectinases when grown on whe at bran in solid-state fermentation (SSF) on a laboratory scale in flasks. The downstream processing parameters for recovery of the crude pectinases f rom the fermented bran were optimised. Optimum time and temperature of extr action were determined to be 15 min and 30 degrees C. The enzyme could be c oncentrated at least 4-fold in the extract by sequential extractions. Extra ction using water or acetate buffer (pH 4.3) containing sodium sulphate res ulted in maximum enzyme recovery. Colour and polysaccharides in the enzyme extract could be minimised by treatment with sodium chloride and activated charcoal. Concentration of the enzyme by ultrafiltration resulted in a 50-f old concentration of activity with 91% recovery. (C) 1999 Elsevier Science Ltd. All rights reserved.