Background and purpose: Biosurfactants are amphiphilic biological compounds produced extracellularly or as part of the cell membranes by a variety of microorganisms. The aim of this study was to identify a strain of bacteria of the genus Acinetobacter.spp biosurfactant producers.
Materials and Methods: In this study, different samples of oil, water and soil contaminated with oil were prepared. Hemolytic activity, emulsification activity and measurement of surface tension were used and selected strains were identified by biochemical tests. The nature and effect of bacterial biosurfactant was evaluated for strain selection.
Results: In this study, eighty eight bacterial strains were isolated. Twenty four strains have been isolated from the isolated strains with hemolytic activity, among which 12 strains with high emulsification activity of 70% were separated. Finally, 4 strains were able to reach the surface tension to less than 40mN/m. On the basis of biochemical tests, a strain selected for this study were identified as Acinetobacter ssp The nature of the biosurfactants were determined by TLC, kind of the glycolipid. Furthermore, the produced biosurfactant of the selected strain had antibacterial activity against six infectious bacteria. The most sensitive ones to the effects of bacterial biosurfactant extract of Acinetobacter ssp, were Staphylococcus aureus and the most resistant bacteria to extract were Proteus mirabilis, the results of MIC, MBC showed that Extract dilution MIC at 63 and MBC Extract in concentration of 125 mg/ ml on Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa were the most effective. The findings indicated that the bacterial strains with over 70% of emulsification and the surface tension below 40 mN/m, are able to produce biosurfactant and oil degradation having stronger antibacterial effects.
Conclusions: According to these results it can be said that this bacterium has a great potential for applications in biotechnology and environmental requirements.
Type of Study:
Research Article |
Subject:
Cellular and molecular Received: 2014/07/24 | Accepted: 2014/07/24 | Published: 2014/07/24