Formation of Petroleum Hydrocarbons from Prokaryote Biomass: 4. Formation of Petroleum Biomarker Hydrocarbons from the Biomass of Halomonas titanicae Bacteria Isolated from Romashkino Crude Oil

Relationships of the distribution of petroleum biomarker hydrocarbons (biomarker HCs), namely, n-alkanes, isoprenanes, n-alkylcyclohexanes, steranes, terpanes, and n-alkylbenzenes, in the soluble fraction and in thermolysis products of the insoluble fraction of the biomass of Halomonas titanicae bacteria isolated from the Romashkino crude oil were studied. The relative distribution of biomarker hydrocarbons in the soluble fraction of the bacteria, compared to that in thermolysis products of the insoluble fraction of the bacteria, is closer to that in the crude oil from the Romashkino field. Both in the soluble fraction and in thermolysis products of the insoluble fraction of the Halomonas titanicae bacterial biomass, homologous series of n-alkanes C-10-C-40, isoprenanes C-10-C-20, n-alkylcyclohexanes C-10-C-30, and n-alkylbenzenes C-10-C-30 were found. Among isoprenanes, pseudoregular C-17 isoprenane, which is absent in all crude oils, is also formed. Presumably, it is formed from an irregular isoprenene, squalene, which was detected both in the soluble fraction and in thermolysis products of the insoluble fraction of Halomonas titanicae bacteria. Among cyclic HCs, tetra- and pentacyclic compounds (steranes and terpanes) are formed in all the cases. The values of the pristane/phytane ratio as a genetic parameter and the distribution of regular C-27-C-29 steranes are close to those in the crude oil from the Romashkino field.