Efficient biodegradation of crude oil by novel Pseudomonas aeruginosa strain isolated from petrochemical wastewater: identification and optimization

Abstract

One of the most noticeable risks that challenge the lives of organisms and human health is the entry of petroleum compounds such as crude oil into the environment. Herein, a novel strain of crude oil-degrading bacteria, KSH-P1, identified from petrochemical wastewater was isolated and purified. The most efficient strain was identified by 16S rDNA sequencing which was used for the crude oil degradation experiments. The operational variables that affect degradation were optimized by response surface methodology based on a quadratic model achieved from a Box–Behnken design. The maximum biodegradation was determined at pH of 7.88, temperature of 35.54 °C, and yeast extract of 0.5 g/L. The model had R 2 , R adj 2 and R pred 2 values of 0.9966, 0.9906 and 0.9495, respectively. The crude oil biodegradation from petrochemical wastewater in the selected model experiments varied from 18.31% to 76.71%. The maximum biodegradation based on multiple response prediction of variables and validation test were 78.63% and 79.03%, including high prediction accuracy of the model to determine the optimal operating conditions of Strain-KSH-P1 for crude oil degradation. Considering the ability of KSH-P1 in the biodegradation of various crude oil compounds, the isolated strain can be used efficiently for the bioremediation of petroleum compounds.