Sanitization of immobilized biocatalysts for the production of 6-aminopenicillanic acid

Five different chemical reagents and gamma-rays were tested for the sanitiz ation of immobilized biocatalysts with high penicillin G acylase (PGA) acti vity. The most effective chemical reagents were N-cetyl-N,N,N-trimethylammo nium bromide (CTAB) and 2-isopropyl-5-methylphenol (thymol). The optimum co ncentration of CTAB for the treatment of the immobilized enzyme was 0.25% [ w/v] and 1 h, for immobilized cells 0.06% [w/v] and 3 h. The optimum concen tration of thymol for the immobilized enzyme was found to be 0.18 [w/v] and 1 h, for immobilized cells 0.27% [w/v] and 2 h. The optimum dose of gamma- rays for the sanitization of the immobilized enzyme was established as 3.2 kGy, for immobilized cells as 4.5 kGy.