Isolation, characterization and growth assessment of biodegrading chlorpyrifos-methyl Bacillus species isolated from Algerian soil

Chlorpyrifos-methyl (CM) is a broad-spectrum organophosphate insecticide, which is widely used in pest control. In this research, the isolation, and biochemical and molecular identification of bacterial strains obtained from three soils located in northeastern Algeria were carried out, as well as the evaluation of their ability to grow in the presence of CM. Out of 48 bacterial isolates between Gram-negative and Gram-positive identified, several were able to grow on mineral agar with at least 25 mg·l–1 of CM. Four bacteria showed the best growth capacity, were identified as Bacillus sp. H1-80, Brevibacterium frigoritolerans strain WJB99 and two Bacillus sp. strains GL5. The strains were tested for their ability to grow on liquid media with CM as the sole energy and carbon source. In general, these strains showed slow but significant growth visualized by the 600 nm turbidity control, suggesting that they could be used for bioremediation applications of CM polluted soils.