Soil samples collected from Ikokwu auto-mechanic village Mile 3, Port Harcourt, Nigeria were analyzed
for the microbiological and hydrocarbon content using standard culture dependent and physiochemical methods. Five sets
of soil designated A, B, C, D and E were collected using composite technique at depth 0 - 15 cm and 15 -30 cm. The
parameters analyzed over an experimental period of 60 days were; total heterotrophic bacteria (THB), hydrocarbon
utilizing bacteria (HUB), total petroleum hydrocarbon (TPH), polyaromatic hydrocarbon (PAH) and total hydrocarbon
content (THC). The total heterotrophic bacterial count (THB) ranges from 1.36 x 10
6 - 1.10 x 10
8 cfu/g for A- E (0-15) cm
and 5.0 x 10
5 - 7.0 x 10
7cfu/g for (15-30) cm while the total hydrocarbon utilizing bacteria (HUB) count ranges from 3.5 x
10
5 - 5.4 x 10
6cfu/g for (0-15)cm and 2.0 x 10
5 - 9.4 x 10
6 for (15-30) cm. The bacteria isolates included the genera
Bacillus
sp.,
Flavobacterius
sp.,
Pseudomonas
sp.,
Micrococcus
sp.,
Arthrobacter
sp.,
Acetobacter
sp.,
Proteus
sp. and
Staphylcoccus
sp. The TPH ranges from 34.32 - 1746.6mg/kg for (0-15) cm and 29.49 -1141.0 mg/kg for (15-30) cm. The
THC ranges from 1.3 - 5.66 mg/kg for (0-15) cm and 0.84 - 2.719 mg/kg for (15-30) cm. PAH recorded a value of 3.246 -
6.890 mg/kg for (0-15) cm and 0.096 - 2.860 mg/kg for (15-30) cm. It is recommended that (i) the hydrocarbon degraders
be enhance and employed for bioremediation of auto-mechanic workshop (ii) it is essential that the metagenomics of spent
engine oil contaminated soil at auto-mechanic workshop be studied for optimum utilization of their potentials.
