Influence of n-alkanes and petroleum on fatty acid composition of a hydrocarbonoclastic bacterium: Marinobacter hydrocarbonoclasticus strain 617

This study concerns the effects of various long-chain n-alkanes, n-alkane m ixtures and Arabian Light crude oil on the fatty acid (FA) composition of a sedimentary marine bacteria (Marinobacter hydrocarbonoclasticus strain 617 ), growing under aerobic conditions, The cultures with n-alkanes, as compar ed with soluble carbon sources, led to greater amounts of saturated and met hyl branched FA (mainly belonging to a Delta (10) series). We observed the appearance or increase of saturated and unsaturated FA with the same carbon chain length (CCL) as the n-alkane carbon source (maximum for n-alkane CCL corresponding to the 'range' of the de novo synthesized fatty acids). We a lso observed a strong control of the oddness/evenness of the CCL of the FA by the oddness/evenness of the n-alkane. A n-alkane utilization index, (sat urated + branched)/monounsaturated fatty acids (SAFA + BFA/MUFA) enabled di scriminating between soluble carbon sources and hydrocarbons. (C) 2001 Else vier Science Ltd. All rights reserved.