Activated charcoal and microfiltration as pretreatment before ultrafiltration of pectinases produced by Aspergillus niger in solid-state cultivation

• Pectinases produced by solid state fermentation were concentrated by UF.
• AC and MF as pretreatment improved the UF performance.
• Fold activity concentration was higher for pretreated extract.
• Combination of MF and UF can be used for high pectinase recovery.

Pectinases produced by solid state fermentation can be concentrated by ultrafiltration for further treatment of fruit juice. In this work, pectinolytic extract was pretreated with activated charcoal (5 g/L) and/or microfiltration (hollow fiber polyamide membrane, pore size of 0.4 μm) before the concentration by ultrafiltration (spiral wound polyethersulfone membrane, 10 kDa). Pretreatment with activated charcoal and microfiltration promoted an increase of 37% in the activity recovery by ultrafiltration compared with the untreated extract. Permeate flux increased from 11 to 24 L/m2 h and the fouling resistance decreased 70%. However, the extract pretreated with only microfiltration presented the same activity recovery (81.4%) after the concentration and the advantage in the decrease the overall process time.