Desorption of microorganisms with hydrophobized surfaces

Abstract

One of the most promising areas in the fight against oil pollution is the use of microorganisms. When eliminating oil pollution, an important task is the selection of surfactants that facilitate the interaction of oil-oxidizing microorganisms with oil products. Dispersion of hydrophobic substances, in particular petroleum hydrocarbons, dramatically increases their surface. In turn, this significantly increases the area of interaction of hydrophobic compounds with oxygen and oil-oxidizing microorganisms. In this work, the effect of humic substances on the aggregate state of various hydrophobic substances is studied. The bioagents were taken strains: Yarrowia lipolytica and Bacillus thuringiensis. Sodium dodecyl sulfate, melanin and humates were chosen as classic surfactants. As sorbing surfaces, slides that were pretreated with silicone or paraffin were used in the work. Experiments have shown that in the presence of sodium dodecyl sulfate, the sorption of cells and spores of microorganisms significantly decreased. With longer exposures, the concentration of cells and spores on the glasses not only did not increase, but even decreased. Moreover, the higher the content of sodium dodecyl sulfate, the weaker the cells and spores of the microorganisms were bound to the hydrophobic surface, and the rate of desorption was higher. It was shown that humates at certain concentrations, like twin, dispersed diesel fuel and fuel oil, and also reduced the amount of cell adhesion. This work was financially supported by the RFBR grant 19-29-05213 mk «Mechanisms for the integrated interaction of soils with oil, oil products and surface-active substances in oil pollution and bioremediation processes».