Abstract

Activated sludge flocs are complex consortia of various micro-organisms. The community structures of samples taken from municipal sewage treatment plants were characterized using fluorescently labelled, 16S and 23S rRNA-targeted oligonucleotide probes in combination with confocal scanning laser microscopy (CSLM). In comparison with conventional epifluorescence microscopy, CSLM considerably improved the capability to visualize directly the spatial distribution of defined bacterial populations inside the sludge flocs. Analyses could be performed at high resolution undisturbed by problems such as autofluorescence or limited spatial resolution in thick samples. In addition, CSLM was used to analyse some structural properties of paraformaldehyde-fixed activated sludge flocs, such as floc size and homogeneity. Typical floc sizes were found to be in the range between 5 and 50 microns. Whereas most of the flocs were completely colonized by bacteria, there were also examples of flocs containing gas bubbles or particles in the interior.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.