Characterization of Mesophilic Bacteria Degrading Crude Oil from Different Sites of Aramco, Saudi Arabia

Abstract

ABSTRACTThe present study was designed to isolate petroleum hydrocarbon degrading bacterial strains from crude oil contaminated sites near the ARAMCO (Jazan, Saudi Arabia). The main aim was to identify a novel microbial comminutes that possess high degradation potential under variant environmental conditions. Total 43 crude oil degrading bacterial consortiums were isolated and six strains were selected based on high growth rate and hydrocarbon degradation ability. The results of 16S rRNA gene sequences analysis showed that these isolated strains were belonged to genus Pseudomonas, Nitratireductor, Bacillus, Staphylococcus and Erwinia. All isolates bacterial strains showed high degradation potential, however, strain 2-IV (Pseudomonas stutzeri) was the most effective for all parameters. The strain 2-IV showed high degradation rate (77%), emulsifying activity (54.5%), and hydrophobicity (65.5%). Moreover, the production of bio-surfactants and great decrease in surface tension (30.5 mN m−1) was also observed for strain 2-IV compared to the other isolates. On the basis of current research it was concluded that these bacterial strain 2-II and 2-IV can be used for cleaning the environment, respectively. However, further study is needed for identification of fungi and actinomycetes that can act on long-chain hydrocarbons in the studied area.