Immobilization of Escherichia coli cells having aspartase activity with carrageenan and locust bean gum

Immobilization of Escherichia coli cells having aspartase activity was carried out by к-carrageenan, or by к-carrageenan and locust bean gum. To enhance operational stability, immobilized cells were treated with a hardening agent, such as glutaraldehyde or glutaraldehyde and hexamethylenediamine. Very active and stable immobilized preparations were obtained when E. coli cells immobilized with к-carrageenan were treated with 85 mm-glutaraldehyde and 85 mm-hexamethylenediamine. The productivities of E. coli cells immobilized with polyacrylamide, к-carrageenan, and к-carrageenan and locust bean gum were compared for production of $\text{l}\text{-}\text{aspartic}$ acid. Among these preparations, E. coli cells immobilized with к-carrageenan and treated with glutaraldehyde and hexamethylenediamine showed the highest productivity.