The influence of metabolites on enzyme based flow injection analysis

The influence of metabolites, as ethanol, l-lactate, pyruvate, acetate, glycerol and succinate, in concentrations, which are typical for Escherichia coli cultivation, on the enzyme based flow injection analysis was investigated. All of these effects are reversible. Alcohol oxidase, glucose oxidase, lactate dehydrogenase, lactate monooxigenase and sarcosine oxidase, immobilized on VA-Epoxy-Biosynth E3 carrier, were used for the analysis of ethanol, glucose, pyruvate, l-lactate and acetate, respectively. The immobilized enzymes were filled in small cartridges and integrated into flow injection analysis systems. The particular metabolites and their combination were used in the concentration range of 0–8 g l−1. Alcohol oxidase and glucose oxidase are strongly impaired by these metabolites, lactate monooxigenase and lactate dehydrogenase are less sensitive to them, and sarcosine oxidase is only slightly influenced by the presence of these metabolites.