USE OF A GENETIC ALGORITHM IN THE DEVELOPMENT OF A SYNTHETIC GROWTH-MEDIUM FOR ARTHROBACTER SIMPLEX WITH HIGH HYDROCORTISONE DELTA(1)-DEHYDROGENASE ACTIVITY
D. Weusterbotz et al., USE OF A GENETIC ALGORITHM IN THE DEVELOPMENT OF A SYNTHETIC GROWTH-MEDIUM FOR ARTHROBACTER SIMPLEX WITH HIGH HYDROCORTISONE DELTA(1)-DEHYDROGENASE ACTIVITY, Journal of chemical technology and biotechnology, 64(4), 1995, pp. 386-392
The production process for Arthrobacter simplex with high specific hyd
rocortisone Delta(1)-dehydrogenase activity was improved by medium opt
imization in parallel shake flask experiments. Using a genetic algorit
hm, the concentrations of 12 medium components (mineral salts and amin
o acid) were optimized within 144 experiments to give maximum specific
hydrocortisone Delta(1)- dehydrogenase activity and biomass yield (fu
ll experimental plan: 1.5 x 10(14) experiments). The specific hydrocor
tisone Delta(1)-dehydrogenase activity was improved by a factor of 4.5
to 1800 U g(-1). With the optimized medium composition in a stirred t
ank reactor for batch production of A. simplex, a specific hydrocortis
one Delta(1)-dehydrogenase activity of 2000-3000 U g(-1) dry biomass w
as achieved depending on harvest time (previously reported data: 18-37
U g(-1)).