Storage stabilization of enzyme activity by poly(ethyleneimine)

The effect of mixing penicillin acylase with poly(ethyleneimine) is discussed. The properties of the polymer-enzyme system were evaluated for a wide range of enzyme concentrations (0.3–45.5 mg/cm³) and poly(ethyleneimine) concentrations (0.0001–10% wt). It was shown that addition of poly(ethyleneimine) to crude enzyme preparation caused precipitation of ballast protein and stabilization of the enzyme fraction remaining in the supernatant. The soluble fraction had stable activity for 21 days storage at 37 °C while the native enzyme lost about 80% of its initial activity. Additionally, it was ascertained that the polymer very slightly affected the properties of penicillin acylase in the PEI-enzyme preparations. Finally, possible ways of using the polymer-enzyme preparations in a membrane reactor are suggested.This work was supported by Government Committee of Science: Grant KBN # 3 0321 91 1