Monitoring of the bioconversion of glycerol to dihydroxyacetone with immobilized Gluconobacter oxydans cell using thermometric flow injection analysis

The bioconversion of glycerol to dihydroxyacetone (DHA) by Gluconobacter ox ydans cells was monitored by flow microcalorimetry. DHA was produced in an air-lift reactor using bacterial cells immobilized in calcium pectate gel. Glycerokinase and galactose oxidase were immobilized on controlled pore gla ss and used for the determination of glycerol (substrate) and dihydroxyacet one (product), respectively. Concentration values obtained by flow microcal orimetry were in a good correlation with a spectrophotometric reference met hod. Furthermore, flow microcalorimetry can be used for on-line monitoring of the process. (C) 2001 Elsevier Science Ltd. All rights reserved.