Table of Contents
ISRN Biotechnology
Volume 2013, Article ID 250749, 13 pages
Research Article

Biofilm-Mediated Enhanced Crude Oil Degradation by Newly Isolated Pseudomonas Species

Department of Biological Sciences, Indian Institute of Science Education & Research-Kolkata, Mohanpur Campus, Nadia 741252, India

Received 31 December 2012; Accepted 25 January 2013

Academic Editors: W. J. Ernst, W. A. Kues, O. Pontes, S. Sanyal, and J. Sereikaite

Copyright © 2013 Debdeep Dasgupta et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The bioavailability of organic contaminants to the degrading bacteria is a major limitation to efficient bioremediation of sites contaminated with hydrophobic pollutants. Such limitation of bioavailability can be overcome by steady-state biofilm-based reactor. The aim of this study was to examine the effect of such multicellular aggregation by naturally existing oil-degrading bacteria on crude oil degradation. Microorganisms, capable of utilizing crude oil as sole carbon source, were isolated from river, estuary and sea-water samples. Biochemical and 16S rDNA analysis of the best degraders of the three sources was found to belong to the Pseudomonas species. Interestingly, one of the isolates was found to be close to Pseudomonas otitidis family which is not reported yet as a degrader of crude oil. Biodegradation of crude oil was estimated by gas chromatography, and biofilm formation near oil-water interface was quantified by confocal laser scanning microscopy. Biofilm supported batches of the isolated Pseudomonas species were able to degrade crude oil much readily and extensively than the planktonic counterparts. Volumetric and topographic analysis revealed that biofilms formed in presence of crude oil accumulate higher biomass with greater thickness compared to the biofilms produced in presence of glucose as sole carbon source.