Strengthening detoxication impacts of Coprinus comatus on nickel and fluoranthene co-contaminated soil by bacterial inoculation.

To develop an efficient and environmental-friendly approach to detoxicate nickel (Ni) and fluoranthene co-contaminated soil, the combined application of Coprinus comatus (C. comatus) with Serratia sp. FFC5 and/or Enterobacter sp. E2 was investigated. The pot experiment tested the influences of bacterial inoculation on the growth of C. comatus, content of Ni in C. comatus, Ni speciation in soil, fluoranthene dissipation, soil enzymatic activities, bacterial population and community structure. With the inoculation of bacteria, the fresh weights of C. comatus, concentration of Ni in C. comatus and the dissipation rates of fluoranthene were increased by 17.73-29.38%, 68.97-204.97% and 34.84-60.90%, respectively. Notably, results illustrated that the co-inoculation of FFC5 and E2 showed better effect in biomass enhancement, Ni accumulation and fluoranthene dissipation than solitary inoculation. Simultaneously, higher soil enzymatic and microbiological activities suggested that the integrated detoxication method of bacteria and C. comatus could improve soil quality. Therefore, we can infer that bacterial inoculation strengthened detoxication effect of C. comatus in Ni-fluoranthene co-contaminated soil, indicating that the combined application of C. comatus and bacteria can be an efficient alternative for detoxicating Ni and fluoranthene co-contaminated soil.