Smaller amounts of glycolipids were produced from phenanthrene than naphthalene. Since it is much less water soluble
(1.3 mg/liter) than naphthalene, it is probable that cells required more time to adapt themselves to the utilization of this
poorly accessible PAH.The rationale behind biosurfactant production on PAHs is that it should stimulate itself by enhancing the substrate availability.An accumulation of naphthalene degradation metabolites was observed when concentrations of glycolipids in the medium started to increase abruptly. This can be explained b the increasing amount of available naphthalene due to the solubilizing effect of biosurfactants (as indicated by the concentration of pseudosolubilized naphthalene). Similar observations in the presence of synthetic surfactants have been reported.