A complementary approach to identifying and assessing the remediation potential of hydrocarbonoclastic bacteria

• Published in: Journal of microbiological methods Vol. 88; no. 3; pp. 348 - 355
• Main Authors: Kadali, Krishna K., Simons, Keryn L., Skuza, Pawel P., Moore, Robert B., Ball, Andrew S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2012; Elsevier
• Subjects: bacteria; Bacteria - classification; Bacteria - growth & development; Bacteria - isolation & purification; Bacteria - metabolism; Biolog MT plates; Biological and medical sciences; Bioremediation; Cluster Analysis; Culture Media - chemistry; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; DNA, Ribosomal - chemistry; DNA, Ribosomal - genetics; Environmental Pollutants - metabolism; Environmental Restoration and Remediation - methods; Fundamental and applied biological sciences. Psychology; genes; hexadecane; Hydrocarbonoclastic bacteria; Hydrocarbons - metabolism; Microbiology; multivariate analysis; naphthalene; oils; phenanthrene; Phylogenetic analysis; Phylogeny; ribosomal DNA; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA; Weathered crude oil; Cluster analysis; Phylogenetic analysis; Weathered crude oil; Biolog MT plates; Bioremediation; Hydrocarbonoclastic bacteria; Hydrocarbon; Crude oil; Bacteria; Phylogeny
• DOI: 10.1016/j.mimet.2011.12.006
• ISSN: 0167-7012

The isolation and assessment of hydrocarbonoclastic bacteria often represents a key strategy in the bioremediation of hydrocarbon-contaminated sites. However the isolation and assessment of such bacteria is often a lengthy and expensive procedure. The aim of this study was to identify potential isolates for use in the remediation of hydrocarbon contaminated sites using a combination of selective isolation plating, the Biolog system and subsequent multivariate analyses. The use of weathered oil as the main C source restricted the number of isolates growing to 5×102CFUg soil−1. Isolates (n=96) were then assessed individually using Biolog MT2 plates with seven different hydrocarbons (dodecane, tridecane, hexadecane, octadecane, eicosane, naphthalene and phenanthrene). The results indicated that all isolates were able to grow on at least one hydrocarbon from the seven chosen. This confirmed that the isolation media developed was selective in isolating hydrocarbonoclastic bacteria only. Cluster analysis of Biolog data separated the isolates into two discrete clusters with cluster 2 identifying hydrocarbonoclastic bacteria that are effective in degrading a variety of contaminants. Further study on the isolates from cluster 2 was carried out based on their phylogenetic analysis. Phylogenetic analysis of 28 bacterial isolates from cluster 2 based on the 1500bp sequences from 16S rDNA genes using MRBAYES confirmed all isolates as being hydrocarbonoclastic, providing supportive evidence that isolates from cluster 2 have a potential use in bioremediation. This approach could improve both the speed and efficiency of the commercial bioremediation process. ► We identified bacteria for the remediation of hydrocarbon contaminated sites. ► Weathered oil as the main carbon source restricted the number of isolates growing. ► 96 bacteria were able to grow on at least one hydrocarbon from the seven chosen. ► Cluster analysis separated the bacterial isolates into two discrete clusters.