Oil dispersion characterization of microorganisms producing biosurfactants

Al-Farabi Kazakh National University, Almaty, 050040, Kazakhstan

^* Corresponding author: gulzhan.kayirmanova@kaznu.edu.kz

Abstract

The article is dedicated to studying the ability of crude oil emulsification and displacement by bacteria producing low-molecular-weight biosurfactants. Six hydrocarbon-oxidizing cultures of microorganisms were used in this study: 3 strains of Pseudomonas aeruginosa (T1, T4, D2) and 3 Bacillus cultures: Bacillus licheniformis A3, Bacillus subtilis subsp. subtilis A12, Bacillus subtilis A9 from the collection of the Biotechnology Department of Al-Farabi Kazakh National University.

The research findings indicate that cells of P. aeruginosa T1 exhibited maximum emulsifying and displacing properties, with an E24 value of 76.4% and an oil displacement ability of 5.1 cm. Among the three genes responsible for the production of low-molecular-weight biosurfactants, the presence of one gene, rhlA, responsible for the synthesis of rhamnolipid biosurfactants, has been confirmed. It was demonstrated that strains P. aeruginosa T1, P. aeruginosa T4, B. subtilis A9, and B. subtilis subsp. subtilis A12 showed high emulsifying activity, making them potentially effective for application in biotechnological processes aimed at enhancing oil recovery from mature reservoirs and in bioremediation processes.