Bioremediation of aromatic hydrocarbons contaminated soil from industrial site using surface modified amino acid enhanced biosurfactant

Abstract

Surface modified lipopeptide biosurfactant (BS) with enhancement of amino acids was produced using Bacillus Malacitensis. The aromatic hydrocarbons from contaminated soil were removed by BS soil washing process and bioremediation using activated functionalized carbon-BS matrix (AFC-BS). The Central Composite Design (CCD) showed the optimum time100 h; pH 7; temperature 30°C on maximum yield of BS. The amino acid profiling of BS reveals the enhancement of amino acids especially polar amino acids and its importance in the formation of micellar structure for the tight packing of aromatic hydrocarbons from industrial contaminated soil. AFC-BS matrix was implanted directly into the contaminated soil for 28 days and found 61.80 % of Total Petroleum Hydrocarbon (TPH) removal efficiency which is high compared to the AFC treated soil. The compounds were extracted from contaminated soil and AFC-BS matrix, found similar peaks in high performance liquid chromatography, which reveals the ability of BS to remove aromatic contaminants. The soil toxicity was also analyzed by seed germination and found improvement in the growth of seeds. The germination of seeds increased from 60 % to 100 % and the phytotoxicity of root and shoot was reduced from 89.50 %, 88.45 % to12.55 %, 11.87 % respectively.