Isolation, Screening and Characterization of Biosurfactant Producing Organisms from Soil Samples

Abstract

Isolation of organisms were carried out from oil contaminated soil. A total of 25 strains were obtained. Biosurfactant producing ability of these isolates were screened using Oil displacement assay. The potential biosurfactant producers were characterized and identified as Acinetobacterbaumanii, Pseudomonas aeruginosa, Macrococcuscaseolyticus, Aspergillusnigerand Aspergillusfumigatus (5). Out of 25 organisms isolated, 10 strains were able to displace oil within 1 min when the cell-free supernatant (CFS) was added which was assayed by the Oil Displacement test. The CFSs of Acinetobacterbaumanii and Aspergillusfumigatus demonstrated remarkableemulsificationindicesof70percent(againstdiethylether)and65percent(againsttoluene).According to platinum Du Nouy ring tensiometer analysis, biosurfactant produced by Aspergillusfumigatus has the highest surface tension reduction capacity with a value of 50mN/m, whereas biosurfactant extracted from Acinetobacterbaumanii has the best CMC. Biosurfactants produced from environmental strains have the potential to be used in microorganism-based biodegradation processes of hazardous hydrocarbons, as well as in Industrial and Medical Microbiology.