Biosurfactant assisted design treatments for remediation of petroleum contaminated soil and metabolomics based interactive study with Brassica nigra L

Soil contaminated with petroleum hydrocarbons has been considered as a serious problem for more than two decades, as it inhibits microbial population, soil enzymatic activity and exhibits abiotic stress in plants as well as affects their metabolites. In the present study, a novel and effective treatments for managing petroleum contaminated soil has been developed. The design treatments were grouped in five classes (T1, T2, T3, T4 and T5) which include petroleum contaminated soil, cow dung, cow urine and crude biosurfactant in various concentrations. After, 90 days of treatment the soils of each group were screened for microbial population dynamics, enzymatic activity, oil reduction assay, SEM and FTIR analysis. The treated soils were further employed for growing Brassica nigra L and targeted metabolomics based approach study was executed to demonstrate the effect of the treatments on the chlorophyll metabolites. The results revealed that treatments (T1, T2, T3 and T4) enhanced the microbial population dynamics and enzymatic activity of the soil with maximum 67% oil reduction in the treatment T1 (600 g Petroleum Contaminated Soil + 400 g Cow Dung + 200 ml Cow Urine + 50 ml crude Biosurfactant + 250 ml Water). Further, the results of growth parameters and targeted metabolomics based model study complemented the effectiveness of the design treatments as variation of growth parameters and chlorophyll metabolites were observed. Hence, the treatments and metabolomics model developed and can be applied commercially as an effective way for the restoration of petroleum contaminated wastelands .