Biosurfactants production ability of lactic acid bacteria strains, emulsification activity and cell adhesion to hydrocarbons

Abstract

The paper presents the results of research carried out for screening of 10 lactic acid bacteria strains with antifungal activity for their ability to produce biosurfactants and to select the most performant strains for further biotechnological application as hydrocarbon-degraders in bioremediation of oil-polluted soils. All the strains of lactic acid bacteria were able to form circle displacement area in engine oil 2T with various diameters, confirming the production of biosurfactants in various amounts. Emulsification activity was registered, with values of emulsification index E24 ranging from minimum 25.75% for the strain LAB 132 to maximum 75.93% for the strain LAB 13. Bacterial cells presented adhesion to hydrocarbons (kerosene), degrees of hydrophobicity variable, ranged between 25,57% for LAB 58 and 75,42% for Lpl and formed emulsions stable for over 7 days. Results of the assay of ionic charge revealed the anionic nature of the biosurfactants.