Biodegradation of atrazine and bioremediation of atrazine- contaminated soil by two groups of mixed bacteria and bacterial consortium

Atrazine is an s-triazine herbicide that has been used widely over 50 years. This has resulted in the contamination of surface water, groundwater and soil. For the bioremediation of atrazine-contaminated environments, we investigated the biodegradation of atrazine and bioremediation of atrazine-contaminated soil by two groups of mixed bacteria (Pseudomonas sp. ADP and Arthrobacter aurescens TC1; Arthrobacter sp. AD30 and Pseudomonas sp. AD39) and a bacterial consortium. The biodegradation experiments indicated that after the minimal medium containing 300 mg/L atrazine as nitrogen source and 3000 mg/L sucrose as carbon source were inoculated with the above-mentioned two groups of mixed bacteria and bacterial consortium and incubated at 30°C with shaking for 48 h, atrazine were removed by 80% (ADP+TC1), 97% (AD30+AD39), and 96% (bacterial consortium), respectively. The bacterial consortium and the mixed bacteria containing Arthrobacter sp. AD30 and Pseudomonas sp. AD39 exhibited higher atrazine biodegradation activities. A bioremediation trial of atrazine-contaminated soil by the bacterial consortium and mixed bacteria containing AD30 and AD39 have indicated that after incubating for 15 d at 30°C atrazine contained in soil (100 mg/kg) were completely removed. These results indicated that the bacterial consortium and the mixed bacteria containing AD30 and AD39 are good candidates for use in bioremediation of atrazine-contaminated soil.