Recovery of Acinetobacter radioresistens lipase by hydrophobic absorption on a nonwoven fabric

The lipase of Acinetobacter radioresistens was recovered from fermentation broth by adsorption on a hydrophobic nonwoven fabric, which consists of a polypropylene core and a polyethylene surface. The adsorption isotherm of the lipase on the nonwoven fabric was compared with that of Amberlite resins (XAD-4, XAD-16, XAD-1180, and XAD-7HP). It was found that the Freudlich model, expressed on the basis of lipase activity, could describe all of the adsorption isotherms and the nonwoven fabric possessed the highest binding capacity for the lipase. The adsorption isotherm on the nonwoven fabric could precisely predict the operation of a two-stage crosscurrent adsorption. For desorption of lipase from the nonwoven fabric, 0.05 M urea was found to be the most effective among those examined. For a single-stage desorption, the recovery yield (based on the adsorbed lipase) observed was 55%, and could reach 85% if the desorption were performed twice. Applying the nonwoven fabric in a 20-cm adsorption column and eluted with 0.05 M urea, lipase recovery, based on that had been adsorbed, could reach 89%. Taking a further count of its low price and availability, the nonwoven fabric could have a great potential being used in the downstream processing.