Isolation and characterisation of a new lipopeptide biosurfactant produced by Arthrobacter sp. MIS38

A surfactant (a contraction of the term surface-active agent) is adsorbed and concentrated at the surface to decrease the work needed to create unit area of surface (the surface free energy per unit area, or surface tension) [1]. This property is micelle formation; the property that surface-active solutes have of forming colloidal-sized clusters in solution. Detergency and solubilisation depend on the existence of micelles in solution. The minimum surface tension and critical micelle concentration are parameters used to measure the efficiency of surfactant systems. Many bacteria living in an oilfield produce surfactants (biological surfactants, BS) to solubilise and effectively take up hydrophobic nutrients inside the cell [2, 3]. BS also is antibiotic showing a variety of anti-microbial activities; however, their mechanism of action is not well understood [4].