Study of factors influencing the degradation of heating oil by Acinetobacter calcoaceticus MM5

The ability of Acinetobacter calcoaceticus MM5 to degrade heating oil was studied. Certain culture conditions relevant to the degradation of this petroleum derivative were also analyzed. Degradation of heating oil by MM5 was followed by gas chromatography during a 30-day incubation period. A. calcoaceticus MM5 degraded essentially the n-alkane components of the fuel, and left the branched hydrocarbons pristane and phytane undegraded. The degradation of heating oil was favoured by aeration of the cultures. There was an absolute nutritional requirement for nitrogen and phosphorus sources for hydrocarbon degradation. Strain MM5 degraded heating and diesel oil to a similar extent. The presence of commercial additives in the heating oil did not modify the degradation of this fuel. Infrared spectroscopy of remaining heating oil after incubation with strain MM5 showed the appearance of two new bands, corresponding to compounds with carbonyl groups derived from the metabolism of hydrocarbons.