New automated procedure to determine the contribution of filamentous bacteria in activated sludge flocs

Use of DAIME for characterisation of activated sludge flocs

“…The fi lamentous bacteria are a nuisance constituent of activated sludge fl ocs and the fi laments to aggregates ratio has been found as important factor for monitoring bulking and sedimentation issues. For this reason, separate analysis of aggregates and fi lamentous bacteria is recommended (Pandolfi et al 2007, Liwarska-Bizukojć et al 2013, Khan et al 2015. It is important to emphasise that the proposed procedure is suitable for sludges without or with low fi laments content.…”

“…Visilog by Noesis (Motta et al 2001, Pandolfi et al 2007), Matlab (Mesquita et al 2010, Khan et al 2015 or NIS Elements AR by Nicon (Liwarska-Bizukojć et al 2013). Moreover, there are methods that allow for segmentation of an image to show the area of an image covered specifi cally by fl ocs, fi lamentous bacteria or protozoa separately (Mesquita et al 2010, Liwarska-Bizukojć et al 2013.…”

“…The image processing process depends on the chosen method and the purpose of analysis. It may include background correction and transfer of RGB (Red Green Blue) images to grey scale ones, debris rejection, image segmentation and measurement of morphological parameters (Liwarska-Bizukojć et al 2013). DAIME (Digital Image Analysis in Microbial Ecology) is a software developed as a tool for image analysis of biological samples and created by Microbial Ecology Department at Vienna University of Technology.…”