Screening, identification and structuralcharacterization of biosurfactant- producingbacteria isolated from oil contaminated field

In this study ten bacterial strains were isolated from oil contaminated soil in southwest of Iran.The isolated bacteria were selected by using different methods as drop collapse, oil spreadingtest, blood agar hemolysis, emulsification activity and surface tension. The biosurfactant whichwas produced as a primary metabolite by potent isolate associated with the growth of strain 2IRand showed ability to reduce surface tension of the medium to 32 mN/m. Acid precipitatedbiosurfactant has critical micelle concentration (CMC) of 120 mN/m. Isolated strain wasidentified by morphological, biochemical and partial 16SrRNA gene sequencing as Bacilluspumilus 2IR. Preliminary characterization revealed that the produced biosurfactant has alipopeptide composition as determined by HPLC and FTIR. Also, 1H, nuclear magneticresonance analysis confirmed it to be lipopeptide. Properties and characteristics of thebiosurfactant produced by B. pumilus 2IR suggesting potential commercial application, such asenhance oil recovery, bioremediation, environment and food industries

کلیدواژه ها:

Biosurfactant ، Lipopeptide ، Surface tension ، Bacillus pumilus ، Critical micelleconcentration