Bioremediation of diesel oil contaminated soil by a novel isolated potential oil degrading staphylococcus argenteus MG2 bacteria using biostimulation method

Abstract

The potential oil-degrading isolate Staphylococcus argenteus MG2 was used for bioremediation of oil-contaminated soil. Hydrocarbon degradation by the soil microorganisms was evaluated in a soil experimentally contaminated with diesel oil. The effects of six different biological treatments on hydrocarbon degradation were determined during a 50 days incubation period to evaluate biostimulation via inorganic fertilizers (NPK) or manure (compost) with and without inoculum of Staphylococcus argenteus MG2. Eight soil samples were used: (S) uncontaminated control soil; (CS) contaminated soil; (CSF) contaminated soil + N-P-K fertilizer; (CSC) contaminated soil + compost; (CSI) contaminated soil + Inoculum; (CSFI) contaminated soil + N-P-K fertilizer + Inoculum; (CSCI) contaminated soil + compost + Inoculum; (SCSCI) sterile (oil) contaminated soil + compost + Inoculum. Percentage of oil degradation during bioremediation treatment of 50 days was found to be (CS) - 32%, (CSF) - 70.80%, (CSC) - 75%, (CSI) - 84.40%, (CSFI) - 91%, (CSCI) - 93%, (SCSCI) - 94% respectively. Results showed that not only inorganic nutrients NPK and compost stimulated hydrocarbon biodegradation but inoculation of Staphylococcus argenteus MG2 also enhanced hydrocarbon degradation. The microbial count was found to be higher in SCSCI soil sample. The germination percentage and growth of leguminous plant (Vigna radiata) in the treated soil was also notably greater. It may be concluded that the Staphylococcus argenteus MG2 bacteria possess remarkable oil-degrading properties and can be effectively employed in the bioremediation of oil-contaminated soils and can be used for agriculture purpose.