Abstract
In this study, we conducted a weathered crude oil (w. oil)-degrading experiment with five different soil samples in order to investigate the biodegradation of alkanes. Two soil samples, soil one (I) and five (V), showed the excellent ability to biodegradade both normal alkanes (C10-C36 alkanes) and branched alkanes (pristane, phytane). We isolated several alkane-degrading bacteria from these soil samples. Isolated bacteria were classified into 3 groups based on their 16S rDNA sequences. The changes in population of these alkane-degrading bacteria were analyzed quantitatively by polymerase chain reaction (PCR) using specific primer sets. As a result, the concentration of group 1 bacteria (Rhodococcus spp.) that were able to degrade both normal and branched alkanes markedly increased due to enrichment with w.oil in soil one (I) and five (V). These results indicated that the group 1 bacteria that belong to the Rhodococcus genus played an important role in degrading alkanes in petroleum-contaminated soil under biostimulated conditions.
