Title: Dynamic laser speckle and fuzzy mathematical morphology applied to studies of chemotaxis towards hydrocarbons

Authors: Melina Nisenbaum; Agustina Bouchet; Marcelo Nicolás Guzmán; Jorge Froilán González; Gonzalo Hernán Sendra; Juan Ignacio Pastore; Marcelo Trivi; Silvia Elena Murialdo

Addresses: Biochemical Engineering Group, Faculty of Engineering, Chemistry Department, National University of Mar del Plata (UNMdP), Juan B. Justo 4302, (7600) Mar del Plata, Argentina ' Digital Processing Image Group, Faculty of Engineering, Electronics Department, UNMdP and CONICET, Juan B. Justo 4302, (7600) Mar del Plata, Argentina ' Laser Laboratory, Faculty of Engineering, UNMdP and Optical Research Center (CIOp), CONICET, La Plata-CIC. Juan B. Justo 4302, (7600) Mar del Plata, Argentina ' Biochemical Engineering Group, Faculty of Engineering, Chemistry Department, UNMdP, Juan B. Justo 4302, (7600) Mar del Plata, Argentina ' Laser Laboratory, Faculty of Engineering, UNMdP and CIOp, CONICET, La Plata-CIC, P.O. Box No. 3 1897, Gonnet, (1900) La Plata, Argentina ' Digital Processing Image Group, Faculty of Engineering, Electronics Department, UNMdP and CONICET, Juan B. Justo 4302, (7600) Mar del Plata, Argentina ' CIOp, CONICET, La Plata-CIC, P.O. Box No. 3 1897, Gonnet, (1900) La Plata, Argentina ' Biochemical Engineering Group, Faculty of Engineering, Chemistry Department, UNMdP and CIC, Juan B. Justo 4302, (7600) Mar del Plata, Argentina

Abstract: The movement of the microorganisms towards a higher concentration of the chemical attractant is called positive chemotaxis and is involved in the efficiency of chemical degradation. Several studies are focused in this field related to genomics, and towards demonstrating chemotactic responses by bacteria, but there is little information related to the activity and morphology of their response. In this work, we use a recently reported dynamic speckle laser method, to process images and to distinguish motile surface patterns per area of colonisation by applying image processing techniques called fuzzy mathematical morphology (FMM). The images of bacterial colonies are usually surfaced, with vague edges and non-homogeneous grey levels. Hence, conventional image processing methods for shape analysis cannot be applied in these cases. In this paper, we propose the application FMM to solve this problem. The approach given was effective to segment, detect and also to describe colonisation patterns.

Keywords: dynamic laser speckle; FMM; fuzzy mathematical morphology; biodegradation; chemotaxis; hydrocarbons; Pseudomonas; swim assay; image processing; bacterial colonies; colonisation patterns.

DOI: 10.1504/IJENVH.2014.060121

International Journal of Environment and Health, 2014 Vol.7 No.1, pp.58 - 69

Published online: 13 Oct 2014 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article