ISSN:
1476-5535
Keywords:
Fluidized bed reactor
;
Cell immobilization
;
Amide hydrolysis
;
Brevibacterium
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Summary This article deals with continuous hydrolysis of acrylamide into acrylic acid using the wild-typeBrevibacterium sp. R312 which can hydrolyze all water-soluble amides into their corresponding acids. Biotransformation has been carried out in a fluidized bed reactor specially designed to obtain good contact conditions between cells entrapped into small calcium alginate beads (2–3 mm) and low-concentration acrylamide solutions (10–40g·l−1). Different flow rates, biocatalyst loads and substrate concentrations have been investigated. Kinetic constants for the immobilized enzyme have been identified. It appears that the Michaelis constant does not change with operating conditions and remains roughly equal to the value obtained for free cells. In contrast, the maximum rate of hydrolysis is considerably decreased, as if only cells on the outskirts of beads were involved in the transformation. On the whole it is proved that corynebacteria cells could be usefully used for the bioconversion of amides in a continuous immobilized cell reactor; the higher the solid hold-up and/or the smaller the beads, the more efficient the biological transformation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01569419
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