Abstract

The research study aimed at isolation and genomic identification of potential crude oil utilizing bacterial and fungal in water and sediment of Orashi River, in the Niger Delta region impacted with petroleum hydrocarbon pollutants. Potential crude oil utilizing bacteria and fungi were cultivated using using spread plate technique on mineral salt medium (MSM) with bonny light crude oil as the carbon source. Cultured samples were incubated for 14days and 10 days for bacteria and fungi respectively. Extraction of the DNA of pure cultured crude oil Utilizing bacteria and Fungi was done using ZR fungal bacterial DNA Prep extraction kit and the extracted DNA was subjected to polymerase chain reaction (PCR). Amplicons was sequenced using Big Dye Terminator Kit. 16S rRNA and Internal transcribed spacer (ITS) sequences were downloaded into the database NCBI using BLASTN algorithm. Results of Total heterotrophic bacteria count ranged from 2.25±2.48×10⁶ – 3.46±3.88×10⁶ CFU/ml and potential crude oil utilizing bacteria were not recovered from the surface water. In the sediment, Total heterotrophic bacteria count range from 1.76±1.75×10⁶ – 2.29±2.41×10⁶ CFU/g while potential crude oil utilizing bacteria ranged from 1.50±2.12×10² – 2.10±1.27×10³CFU/g. Total fungi count ranged from 1.16±1.19×10³ – 6.5±0.64×10³CFU/ml and potential crude oil utilizing fungi ranged from 8.1±0.84×10² – 1.80±1.70×10³CFU/ml in surface water. While Total fungi count ranged from 1.20±1.13×10³ – 2.30±2.40×10³CFU/g and potential crude oil utilizing fungi ranged from 1.30±0.99×10² – 1.20±1.13×10³CFU/g in sediment. Query sequences submitted to GenBank all showed 100% relatedness to the isolates in the database. And were assigned  Accession numbers as Serratia marcescens PV642521, Priestia flexa PV642520 and Pseudomonas aeruginosa PV642519 (hydrocarbonoclastic bacteria); Aspergillus flavus PV642586, Penicillium citrinum PV642585 and Aspergillus fumigatus PV642584 (hydrocarbonoclastic fungi). These autochthonous bacteria and fungi with the potential to utilize crude oil can be used as inoculum in the clean – up of crude oil polluted environment.