Ein Beitrag zur Erhöhung der Aussagekraft des Indikatorparameters Koloniezahl durch ergänzende molekularbiologische Untersuchungen

In the practice of quality control for drinking water, bacterial count is understood to mean the population density of microorganisms that tend to occur in increased numbers under hygienically or technically critical conditions. While quantifying microorganisms is sufficient in the conventional assessment of drinking-water quality, specific problems call for subtler methods. A possible method of reaching this aim is analysing microorganism communities by molecular biological means. Within the framework of the study discussed in this article bacterial-count communities (CFU/ml, 22°C) grown on the standard medium (EN ISO 6222) were compared with the overall bacterial community present in the water sample. Whereas the total bacterial community composed of autochthons did not show any relationship to location, the respective sampling sites within a drinking-water supply system were characterised by specif c bacterial-count communities resulting from local biofilm erosions.