Influence of special surfactants on the microbial degradation of mineral oils

Various surfactants belonging to the group of fatty acid-acylated amino aci ds were tested for their ability to accelerate the microbial degradation of mineral oil. Of the lauric acid-acylated amino acids, aliphatic acids and histidine were found to be the most suitable. By the aid of these compounds additional 20-60% of a residual oil fraction could be degraded. The longer the chain of the fatty acid moiety, the more effective the surfactants are . Natural L-amino acids were more effective than their D-configuration. Sin ce the special surfactants are easily biologically degradable, multiple rep lenishment is required in long-term experiments. The faster, more complete degradation of mineral oil is caused solely by interfacial activity; the gr owth of biomass due to the function of surfactants as substrate had no effe ct. (C) 2000 Elsevier Science Ltd. All rights reserved.