This study investigated the presence and hydrocarbon degrading capabilities of indigenous heterotrophic bacteria in oil polluted soils from Izombe community in Oguta Local Government Area of Imo State, Nigeria. Soil samples collected at 500 m and 1000 m from major spill points were analyzed for physicochemical characteristics and microbial composition using standard microbiological and analytical methods. Results revealed diverse bacterial genera, including Pseudomonas, Bacillus, Acinetobacter, Alcaligenes, Citrobacter, and Serratia, with several strains demonstrating strong hydrocarbon utilizing abilities. Biodegradation experiments conducted over 30 days showed significant reductions in total petroleum hydrocarbons (TPH), with Acinetobacter sp. exhibiting the highest degradation efficiency (99.70%), followed closely by Pseudomonas sp. (99.60%) and Alcaligenes sp. (99.20%). Physicochemical analyses indicated that crude oil contamination altered soil properties, notably reducing nitrate and phosphate levels and increasing acidity. The findings confirm that indigenous bacterial communities in Izombe possess functional genes and metabolic potential necessary for effective biodegradation of Bonny light crude oil. The study concludes that microbial consortia are critical for efficient bioremediation and recommends Acinetobacter sp. as a promising candidate for remediation of hydrocarbon impacted environments in the region.
Nwaehiri et al. (Mon,) studied this question.