Alkaline Phosphatase Enzyme Activity Measurement as a Robust on-line Monitoring Assay for Water Quality Assessment.

Micro organisms maintain their growth by producing enzymes in order to provide low molecular weight inorganic compounds. These compounds could be taken up into the cells from high molecular weight organic compounds which cannot be directly utilized by bacteria. Microbial enzymes are, therefore, directly related to the concentrations and ratios of limiting nutrients, and may be sensitive indicators of organic pollution in aquatic environments.

The objective of this study, which was carried at microLAN company in Waalwijk (NL) and supported by HWL (Het Water Laboratorium, Haarlem, NL), is to validate the results obtained from the BACTcontrol biosensor by comparing the ALP activity with different common water analysis like ATP and Flow Cytometry that are regularly used to assess water quality.

ty of surface water 24 hours per day, 7 days per week. It uses freshly prepared Vibrio fi scheribacteria directly from a luminescent culture. In contact with the surface water the bacteria produce less light as the toxicity increases. The light production is measured with a photomultiplier.