title: Application of rapid enzyme assay techniques for monitoring of microbial water quality.
abstract: Rapid enzyme assay techniques based on direct measurement of beta-d-galactosidase (GALase) or beta-d-glucuronidase (GLUase) activity without selective cultivation are used for rapid estimation of the level of coliform bacteria and Escherichia coli in water samples. Reported detection limits using fluorogenic substrates correspond to culturable target bacteria concentrations that can be appropriate within present guidelines for recreational waters. The rapidity, that is detection within one hour, compromises the specificity of the assay; enzyme activity contributions from other than target bacteria need to be considered, particularly at low levels of target bacteria. Enzyme activities are more persistent than the culturability of target bacteria to environmental and disinfection stress, thus water samples may express enzyme activities of both culturable and viable non-culturable cells.
authors.affiliation: Department of Hydraulic and Environmental Engineering, Norwegian University of Science and Technology, SP Andersens vei 5, NO-7491 Trondheim, Norway. liv.fiksdal@ntnu.no
authors.forename: Liv
authors.initials: L
authors.lastname: Fiksdal
authors.forename: Ingun
authors.initials: I
authors.lastname: Tryland
mesh_terms: D001709:Biotechnology / Q000706:statistics & numerical data; D004755:Enterobacteriaceae / Q000201:enzymology / Q000302:isolation & purification; D004784:Environmental Monitoring; D004926:Escherichia coli / Q000201:enzymology / Q000302:isolation & purification; D005966:Glucuronidase / Q000032:analysis; D006801:Humans; D012680:Sensitivity and Specificity; D014871:Water Microbiology; D014881:Water Supply; D001616:beta-Galactosidase / Q000032:analysis
chemical_list: D001616:beta-Galactosidase; D005966:Glucuronidase