Abstract
Endo-pectate lyase (PATE) secreted by Erwinia carotovora (FERM P-7576) was found to be adsorbed onto the polysulfone hollow fibers during the ultrafiltration. The adsorption of the enzyme was confirmed by FT-IR-DR subtraction spectra. The adsorption curve was in accordance with the typical Langmuir adsorption isotherm. The maximum adsorption of the enzyme occurred at pH 8.3 and at low ionic strength.
For the purpose of preventing PATE from the adsorption onto the polysulfone hollow fibers, the addition of nonionic and cationic surfactant to crude enzyme solution was found to be effective. Among the surfactants, alkyl benzyl dimethyl ammonium chloride (ABDAC) was the best one to prevent the PATE from adsorption. The pretreatment of polysulfone hollow fibers with 0.2% ABDAC solution lead to the same effects as that of surfactant addition in the solution. The polysulfone hollow fibers were treated with 0.25% ABDAC solution for two hours. PATE was recovered quantitatively in the ultrafiltration by use of the polysulfone hollow fibers which was treated with 0.25% ABDAC solution for two hours.
