title: In situ microscopy as a tool for the monitoring of filamentous bacteria: a case study in an industrial activated sludge system dominated by M. parvicella.
abstract: The present study demonstrates the application of in situ microscopy for monitoring the growth of filamentous bacteria which can induce disturbances in an industrial activated sludge process. An in situ microscope (ISM) is immersed directly into samples of activated sludge with Microthrix parvicella as dominating species. Without needing further preparatory steps, the automatic evaluation of the ISM-images generates two signals: the number of individual filaments per image (ISM-filament counting) and the total extended filament length (TEFL) per image (ISM-online TEFL). In this first version of the image-processing algorithm, closely spaced crossing filament-segments or filaments within bulk material are not detected. The signals show highly linear correlation both with the standard filament index and the TEFL. Correlations were further substantiated by comparison with real-time polymerase chain reaction (real-time PCR) measurements of M. parvicella and of the diluted sludge volume index. In this case study, in situ microscopy proved to be a suitable tool for straightforward online-monitoring of filamentous bacteria in activated sludge systems. With future adaptation of the system to different filament morphologies, including cross-linking filaments, bundles, and attached growth, the system will be applicable to other wastewater treatment plants.
authors.affiliation: Institute for Urban Water and Waste Management, University of Duisburg-Essen, Universitätsstr. 15, 45141 Essen, Germany E-mail: thiemo.dunkel@ineos.com.
authors.forename: Thiemo
authors.initials: T
authors.lastname: Dunkel
authors.affiliation: Graduate Program in Electrical and Computer Engineering, Federal University of Technology - Paraná in Brazil, Av. Sete de Setembro 3165, 80230-901 Curitiba, Brazil; Department of Information Technology, Mannheim University of Applied Sciences in Germany, Paul-Wittsack-Str. 10, 68163 Mannheim, Germany.
authors.forename: Philipe Ambrozio
authors.initials: PA
authors.lastname: Dias
authors.affiliation: Institute for Urban Water and Waste Management, University of Duisburg-Essen, Universitätsstr. 15, 45141 Essen, Germany E-mail: thiemo.dunkel@ineos.com.
authors.forename: Erika Lizette
authors.initials: EL
authors.lastname: de León Gallegos
authors.affiliation: Institute for Urban Water and Waste Management, University of Duisburg-Essen, Universitätsstr. 15, 45141 Essen, Germany E-mail: thiemo.dunkel@ineos.com.
authors.forename: Viola
authors.initials: V
authors.lastname: Tacke
authors.affiliation: Institute for Urban Water and Waste Management, University of Duisburg-Essen, Universitätsstr. 15, 45141 Essen, Germany E-mail: thiemo.dunkel@ineos.com.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schielke
authors.affiliation: Institute for Urban Water and Waste Management, University of Duisburg-Essen, Universitätsstr. 15, 45141 Essen, Germany E-mail: thiemo.dunkel@ineos.com.
authors.forename: Tobias
authors.initials: T
authors.lastname: Hesse
authors.affiliation: Department of Information Technology, Mannheim University of Applied Sciences in Germany, Paul-Wittsack-Str. 10, 68163 Mannheim, Germany.
authors.forename: Diego Andrés Sierra
authors.initials: DA
authors.lastname: Fajado
authors.affiliation: Department of Information Technology, Mannheim University of Applied Sciences in Germany, Paul-Wittsack-Str. 10, 68163 Mannheim, Germany.
authors.forename: Hajo
authors.initials: H
authors.lastname: Suhr
authors.affiliation: Department of Biotechnology, Mannheim University of Applied Sciences in Germany, Paul-Wittsack-Str. 10, 68163 Mannheim, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Wiedemann
authors.affiliation: Institute for Urban Water and Waste Management, University of Duisburg-Essen, Universitätsstr. 15, 45141 Essen, Germany E-mail: thiemo.dunkel@ineos.com.
authors.forename: Martin
authors.initials: M
authors.lastname: Denecke
mesh_terms: D039903:Actinobacteria / Q000166:cytology* / Q000502:physiology; D008853:Microscopy; D060888:Real-Time Polymerase Chain Reaction; D012722:Sewage / Q000382:microbiology; D064091:Waste Disposal Facilities; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000382:microbiology*; D014871:Water Microbiology
chemical_list: D012722:Sewage; D062065:Wastewater