Short communication: Production and properties of a biosurfactant synthesized by Arthrobacter protophormiae - An Antarctic strain

This study reports the production of biosurfactant by a psychrophilic strain of Arthrobacter protophormiae during growth on an immiscible carbon source, n-hexadecane. The biosurfactant reduces the surface tension of the medium from 68.0 mN/m to 30.60 mN/m and exhibits good emulsification activity. The strain could grow and produce biosurfactant in the presence of high NaCl concentrations (10.0 to 100.0 g/l). Although the biosurfactant was isolated by growing the organism under psychrophilic conditions (10 degrees C) it exhibited stable activity over a wide range of temperature (30 degrees C to 100 degrees C). It retained its surface-active properties at pH 2 to 12. The biosurfactant was effective in recovering up to 90% of residual oil from an oil saturated sandpack column, indicating its potential value in enhanced oil recovery.