Screening and Characterization of Biosurfactant-Producing Bacteria Isolated from Contaminated Soils with Oily Wastes

Biosurfactants are amphiphilic compounds produced by microorganisms and have diverse uses in industry and agriculture. The biosurfactant producing microbes are helpful in bioremediation of heavy metal, pesticides and hydrocarbon contaminated sites. In this study, isolation and identification of biosurfactant producing strain was assessed. Soil samples from soils contaminated with soybean oil refining waste and hydrocarbon were collected. To confirm the ability of isolates to produce biosurfactant, agar blue plate, oil displacement test, drop collapsed assay and measurement of surface tension were conducted. The endogenous isolate ORA9 from contaminated hydrocarbon soil was found to be a good biosurfactant producer. This isolate produced a maximum biosurfactant production of 2,3 ± 0,8 g/L in fried soybean oil. With biochemical and 16s rRNA analysis the isolate ORA9 was identified as Pseudomonas aeruginosa. The chromatographic analysis revealed the glycolipidic nature and structural composition of the biosurfactant. The biosurfactant was found to emulsify crude oil and remove heavy metals from contaminated water. These abilities of the isolate can be utilized in environmental bioremediation procedures.

کلیدواژه ها:

Biosurfactants ، oily wastes ، Pseudomonas aeruginosa ، heavy metal