The isolation and characterization of hydrocarbon-utilizing bacteria from
petroleum oily sludge collected from crude oil processing plant in Rivers State, Nigeria was
carried out. Microbiological analysis of the sludge sample showed that the microbial load
consisted average of 2.5 x 10
6 cfu/g total heterotrophic bacterial (THB) count, while the
hydrocarbon utilizing bacterial (HUB) count was average of 2.0 x 10
3 cfu/g. Phenotypic
characteristics and phylogenetic analysis of the 16S rRNA gene sequence of the isolates
revealed that they were related to members of the species
Klebsiella pneumonia
,
Klebsiella oxytoca
and
Alcaligenes faecalis
. The 16S rRNA of the isolates showed percentage similarities
to the type strains (99% sequence similarities) of the following;
Klebsiella pneumonia strain
B21 (gi: 922317936),
Klebsella pneumonia strain ICB-C183 (gi: 908478837),
Klebsella oxytoca
strain BCNAI (gi: 846993354),
Klebsella oxytoca strain BC4 (gi: 884060138),
Alcaligenes
faecalis strain IOU PMR (gi: 686028963) and
Alcaligenes faecalis strain AQ-I (gi: 816845513).
Of the six hydrocarbon utilizing bacteria identified, 4(67%) were
Klebsiella species while
2(33%) were identified as
Alcaligenes sp of different strains. The result suggest that these
isolated organisms from the petroleum sludge can be explored and used to promote
environmentally friendly technology clean-up of petroleum hydrocarbon polluted sites in the
Niger Delta region of Nigeria.
