화학공학소재연구정보센터
Biotechnology Letters, Vol.32, No.2, 235-241, 2010
Immobilization of Escherichia coli cells with cis-epoxysuccinate hydrolase activity for d(-)-tartaric acid production
Immobilization of cis-epoxysuccinate hydrolase-containing E. coli for d(-)-tartaric acid production was screened by various methods. The highest recovery of activity was obtained by entrapment in kappa-carrageenan gel. 23.6 g biomass/l and 43.4 g kappa-carrageenan/l were the best immobilization conditions optimized by response surface methodology with 83% yield (114 U/g). Cell autolysis was observed after immobilization. Immobilized cells showed high pH (5-10) stability, thermal (up to 65A degrees C) stability, conversion rate (> 99.5%), enantioselectivity (ee > 99.6%), and were less affected by metal ions and surfactants compared with free cells. Conversion rate for immobilized cells preserved 93% after 10 repeated batches (5% for free cells).