Lipids in marine sediments

Harvey H. R., Fallon R. D., and Patton J. S. (1986) The effect of organic matter and oxygen on the degradation of bacterial membrane lipids in marine sediments. Geochim. Cosmochim. Acta 50, 795-804. 

Organic geochemistry of lipids in marine sediments in the Canary Basin Implications for origin and accumulation of organic matter... 

Volkman, J.K., Farrington, J.W., and Gagosian, R.B. (1987) Marine and terrigenous lipids in coastal sediments from the Peru upwelling region at 15°S sterols and triterpene alcohols. Org. Geochem. 6, 463 -77. 

MacGregor, B. J., Boschker, H. T. S., and Amann, R. (2006). Comparison of rRNA and polar-lipid-derived fatty acid biomarkers for assessment of C-13-substrate incorporation by microorganisms in marine sediments. Appl. Environ. Microbiol. 72, 5246—5253. 

In this chapter, we consider humin to be the residue after successive extraction of sediments by benzene/methanol to remove lipids, dilute acid IN HCl), and 0.5N NaOH. In marine sediments, further treatment with concentrated HF/HCl (1 1 v/v) is required to concentrate the organic matter by removal of mineral matter. This treatment will partially or totally hydrolyze polysaccharides and proteins while probably having little effect on the humic material (Hatcher et al., 1983a). 

Molecular hydrogen is an important intermediate in the degradation of organic matter by microorganisms in anoxic habitats such as freshwater and marine sediments, wet land soils, and the gastrointestinal tract of animals. In these particular conditions H2 is produced during fermentation of carbohydrates, lipids, nucleic acids, and proteins by anaerobic bacteria and,... 

All organisms synthesize carbohydrates, lipids, proteins, and polynucleotides, although the details of their molecular structures can be somewhat species specific. These basic classes of macromolecules have changed little over geologic time. The secondary metabolites are more species specific and have also changed little over geologic time. Many are resistant to degradation, and those provide excellent biomarkers that have been preserved in ancient marine sediments and petroleum deposits. 

First reported in recent marine sediments in 1967 275) have since been found in several marine basins 140, 141) Cooper and Blumer 140) suggested that the isoprenoid acids may provide markers for the contribution of animals lipids to the organic matter of recent sediments... 

Sterols were first found in recent marine sediments in 1964 281) since been reported by other workers 282, 283). No affirmative findings are available on triterpenes in recent sediments. Lipids form up to 20% of soil humus 284) ... 

Sun, M.Y., Aller, R.C., and Lee, C., and Wakeham, S.G (2002) Effects of oxygen and redox oscillation on degradation of cell-associated lipids in surficial marine sediments. Geochim. Cosmochim. Acta 66, 2003-2012. 

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