Relationship between cyclohexyl-alkanoic acids and the acidothermophilic bacterium Alicyclobacillus spp.: Evidence from Brazilian oils

Previous analyses of lacustrine saline petroleum from the Campos Basin (Southeastern Brazil), and marine evaporitic petroleum from the Sergipe-Alagoas Basin (Northeastern Brazil) revealed the presence of a series of alkyl-cyclohexanes and cyclohexyl-alkanoic acids. The origin of these compounds in petroleum has not been discussed in the literature, but bibliographic research revealed that cyclohexyl-alkanoic acids are the main constituents of the lipidic membranes of the bacteria Alicyclobacillus spp. The present study characterized the distribution of ω-cyclohexyl-undecanoic acid in Brazilian marine evaporitic and lacustrine saline oils from the Sergipe-Alagoas and Campos basins, and correlated the occurrence of this class of compounds to the presence of Alicyclobacillus spp. in the formation water and oil samples from the Campos Basin.