Collect. Czech. Chem. Commun. 1982, 47, 2716-2723

Endo-D-galacturonanase immobilized by adsorption on porous polyethyleneterephthalate

Lubomíra Rexová-Benkováa, Jiřina Omelkováa and Vladimír Kubánekb

a Institute of Chemistry, Slovak Academy of Sciences, 842 38 Bratislava
b Department of Polymers, Institute of Chemical Technology, 160 00 Prague 6


Endo-D-galacturonanase of Aspergillus sp. was irreversibly adsorbed on polyethyleneterephthalate in an acetate 0.1 mol l-1 buffer solution of pH 4.2. Immobilization of the enzyme resulted in lowering of its activity, the measure of which depended on the amount of the enzyme fixed on the carrier. The highest relative activity (42.4%) had the preparation containing 5.25 mg of the enzyme per 1 g of the carrier. The velocity and intensity of the sorption of the enzyme depended on the ionic strength of the medium, whilst pH, on the other hand, was of no influence. Endo-D-galacturonanase immobilized in a 0.1 mol l-1 buffer was characteristic a) of its fixation strength in salt solutions of various ionic strength and pH, in a 3 mol l-1 guanidine solution, and also in sodium pectate and pectin solutions, b) of its high stability during a long-lasting storage at 4 °C, c) of its operational stability. The immobilization led to a partial change of the action pattern onto the high-molecular substrate, manifested in lowering the decrease of viscosity to degradation degree ratio.