Verhalten von Mikroorganismen in Trinkwasserverteilungs- und Hausinstallationssystemen Abschlussbericht

In this project molecular biological, immunological and chemical-physical investigations have been performed to study the bacterial colonization on the inner pipe surfaces within the public drinking water pipe net and plumbing works. Materials used in drinking water technology like PE-HD, PVC, steel, copper and cement mortar coated pipes were taken for biofilm formation. The investigations include the determination of the total cell count in comparison with count of respiratory active bacteria (CTC/DAPI-staining), the taxonomic characterization of the microorganisms in biofilms (In Situ-hybridization, FTIR-spectroscopy) and the detection of pathogenic or facultative pathogenic bacterial with molecular biological techniques (PCR and Southern blot hybridization). In addition, conventional cultivation of bacteria were used for biofilm characterization. The investigations were performed in the three areas of drinking water supply of the city Mainz and resulted in a time depended, but also material related biofilm formation, which is also affected by the drinking water conditioning and disinfection measures. Population analysis characterized the biofilms and have shown differences in the biofilm composition depending on the source and chemical quality of the drinking waters. Problematic bacterial like Legionella, fecal streptococci and Mycobacteria could be detected directly without cultivation in biofilms by the use of molecular biological methods. Legionella were found in most of the biofilms, while streptococci were rarely detected. In this project a new detection method for Mycobacteria was developed in cooperation with the group of Prof. Szewzyk, TU Berlin. Sapropytic Mycobacteria could only be detected in biofilms from drinking water supply of the water works Petersaue, but not in the other investigated systems. In addition, the results showed that amoebae were associated with biofilms. (orig.)Available from TIB Hannover: F99B826+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman