identification, purification, and optimization of copper-resistant acinetobacter sp. for crude oil biodegradation

The present study aimed to isolate and identify bacteria resistant to copper ions (cu²⁺) and capable of degrading crude oil from the vicinity of a copper mine. the optimal conditions affecting the biodegradation of crude oil in the presence of cu²⁺ were also investigated. herein, a unique strain with the ability to biodegrade crude oil and tolerate cu²⁺ was isolated and purified. identification results showed that the mentioned strain was most similar to acinetobacter sp. and was designated as za-1. based on the findings, using crude oil as the sole source of carbon and energy, compared to bacterial growth in nutrient broth, leads to a decrease in the strain's tolerance to cu²⁺. based on the results of anova and the rate of crude oil biodegradation by strain za-1, it was determined that all factors studied except nh₄cl concentration had a significant effect on the crude oil biodegradation process. the optimal conditions for crude oil biodegradation were determined to include ph=8, temperature=30 °c, salinity=30 g/l, and nh₄cl concentration of 1.5 g/l. strain za-1 was able to biodegrade 30.70% of crude oil. considering the ability of the purified strain to degrade crude oil and tolerate cu²⁺, the results of this study can be utilized in biological treatment processes for wastewater containing cu²⁺ and contaminated with petroleum compounds.