Improved Production of L-Lysine by Immobilized Biotin Auxotropic Mutant Micrococcus glutamicus AB_(200)

摘要

Experimental studies were carried out to examine the efficiency of whole cell immobilization in calcium alginate beads and agar blocks for the production of L-lysine using a biotin autotrophic mutant Micrococcus glutamicus AB_(200) developed in laboratory by induced mutation from a regulatory mutant Micrococcus glutamicus AB5. Under the same physico- chemical environment, using selected suitable synthetic medium, different parameters for both calcium alginate beads and agar blocks were optimized one by one to maximize the production of L-lysine. Production was increased significantly with cells entrapped in calcium alginate beads compared to free cells with the presence of 0.2(M) CaCl2 in synthetic medium, 0.2 (M) CaCl2for bead formation, 4% sodium alginate, 24 h storage period of beads and 1.5 cell/alginate ratio but the accumulation of was decreased significantly with the whole cell entrapped in agar blocks, compared to free cells.