Culture-dependent characterization of hydrocarbon utilizing bacteria in selected crude oil-impacted sites in Bodo, Ogoniland, Nigeria

Abstract

This investigation was carried out to characterize microbial communities in selected crude oil polluted sites in Bodo community, Gokana Local Government Area of Rivers State, Nigeria. Total heterotrophic bacterial counts ranged from 0.7 to 1.37x10⁷ cfu/g and 0.2 to 5.9x10⁶ cfu/ml while counts of hydrocarbon utilizing bacteria ranged from 0.1 to 8.0 x 10⁶ and 0.2 to 7.5 x 10⁵ cfu/ml for soil, sediment and water, respectively. Physiochemical parameters of all samples were determined. The ranges obtained were temperature 31-33°C, pH 7.5-8.2, conductivity 1134 - 7680 μs/cm, total nitrogen 792.4 - 886.3 mg/kg, nitrate 36.55 - 42.70 mg/kg, total organic carbon 2.06 - 2.18%, total petroleum hydrocarbon 1007 - 1104 mg/kg, vanadium 0.001 - 0.007 mg/kg, iron 3.772 - 4.889 mg/kg, chromium 52.40 - 66.20 mg/kg, nickel 40.02 - 41.62 mg/kg, lead 17.30 - 19.40 mg/kg and zinc 35.10 - 39.50 mg/kg for soil and sediments while water had total nitrogen 868 mg/l, nitrate 40.6 mg/l, total organic carbon 3.1 mg/l, total petroleum hydrocarbon 768 mg/l, nickel 39.2 mg/l, lead 17.3 mg/l and turbidity 250 NTU. Bacteria isolates characterized belonged to these genera Bacillus, Proteus, Pseudomonas, Flavobacterium, Corynebacterium, Serratia, Micrococcus, Klebsiella, Enterobacter and Azotobacter. The findings reveal that there is a high population of active indigenous hydrocarbon utilizing bacteria which can be monitored and enhanced to bring about bioremediation in the study area.

Key words: Hydrocarbon pollution, soil, water, sediments, hydrocarbon utilizing bacteria, Bodo, Ogoniland.