| Abstrakt: |
Mineral waters have been ascertained to exert a pronounced inhibiting effect, that is in proportion in their mineralization and pH values, on the fluorescence of microbial luminescent biosensors. To prevent such adverse reactions masking the effects of chemical pollutants, the authors propose an adjusted procedure for preparing the samples of mineral waters for luminescence biotesting. The first approach is to differentially insert additional quantities of NaCl into the test samples depending on the level of their baseline mineralization to the baseline value 3 g/l, which is provided in the use of the natural sea luminescent bacterium Photobacterium phosporeum as a test object (Microbiosensor B-17 677f). The second approach is to normalize pH to values of not more than 7.5, which are identical in the use of both the Microbiosensor B-17 677f and a recombinant Escherichia coli strain with the cloned lux-operon P. leiognathi (Ecolum-9). This sample preparation maintaining the baseline fluorescence of bacterial biosensors is shown to permit bioluminescence detection of exogenously inserted toxicants in the test samples. |
