Bioremediation of oily hypersaline soil and water via potassium and magnesium amendment.

Ten hydrocarbonoclastic halobacterial species and 5 haloarchaeal species that had been isolated on a mineral medium with oil as the sole carbon source grew better and consumed more crude oil, as measured by gas-liquid chromatography, in media receiving between 0.50 and 0.75 mol/L KCl and between 1.50 and 2.25 mol/L MgSO₄. Chemical analysis revealed that within a certain limit, the higher the KCl and MgSO₄ concentrations in the medium, the more K⁺ and Mg²⁺, respectively, was accumulated by cells of all the tested halobacteria and haloarchaea. Also, in experiments in which total natural microbial consortia in hypersaline soil and water samples were directly used as inocula, the consumption of hydrocarbons was enhanced in the presence of the above given concentrations of KCl and MgSO₄. It was concluded that amendment with calculated concentrations of K⁺ and Mg²⁺ could be a promising practice for hydrocarbon bioremediation in hypersaline environments.