Efficient production of (R)-(-)-mandelic acid using glutaraldehyde cross-linked Escherichia coli cells expressing Alcaligenes sp. nitrilase.
Bioprocess Biosyst Eng
; 37(7): 1241-8, 2014 Jul.
Article
em En
| MEDLINE
| ID: mdl-24317427
ABSTRACT
Recombinant Escherichia coli cells expressing Alcaligenes sp. nitrilase were simply immobilized by direct cross-linking using glutaraldehyde. About 85 % of the total nitrilase activity was recovered under the optimal cross-linking conditions. The thermal stabilities of the cross-linked cells measured at 30, 40 and 50 °C were 4.5-, 5.3-, and 5.1-fold those of the free cells, respectively. The concentration of (R)-(-)-mandelic acid reached 280 mM after merely 2 h transformation with the immobilized cells using 300 mM mandelonitrile as substrate, affording an extremely high productivity of 510.7 g L(-1) d(-1). In addition, operational stability of the immobilized cells was obviously superior to that of free cells, without significant activity loss after 15 cycles of batch reactions or 8 cycles of repeated fed-batch reactions. Therefore, the easy preparation and robust characteristics of the immobilized biocatalyst make it a very promising biocatalyst for high-performance and low-cost production of optically pure (R)-(-)-mandelic acid.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Glutaral
/
Alcaligenes
/
Escherichia coli
/
Aminoidrolases
/
Ácidos Mandélicos
Idioma:
En
Revista:
Bioprocess Biosyst Eng
Assunto da revista:
BIOTECNOLOGIA
/
ENGENHARIA BIOMEDICA
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
China