Calvo, EvaPelejero, CarlesLogan, Graham A2015-12-132015-12-130021-9673http://hdl.handle.net/1885/74773Pressurized liquid extraction has been performed on a suite of deep-sea sediments to assess its capability as an extraction technique in the analysis of molecular biomarkers used in paleoceanography. Specific compounds assessed comprise long-chain alkenones, n-alkanes, n-alcohols and, additionally, one diol and one keto-ol. These have been extracted by both pressurized liquid extraction and ultrasonication for comparison. One key result is that the U37K′ index (based on the degree of unsaturation of the alkenones and used as a paleothermometer in paleoceanography) remains intact after both extraction techniques. In terms of biomarker concentrations, which are often used to qualitatively assess changes in marine productivity and/or terrigenous inputs, pressurized liquid extraction is substantially more efficient than ultrasonication, providing higher amounts of extracted constituents, particularly for polar compounds.Keywords: Biomarkers; Oceanography; Pressure effects; Sediments; Unsaturated compounds; Liquid extraction; Extraction; alcohol derivative; alkane derivative; alkene derivative; biological marker; article; gas chromatography; high performance liquid chromatography; Alkenones; Deep sea sediments; Molecular biomarkers; Pressurized liquid extraction; U37K' index200310.1016/S0021-9673(03)00119-52015-12-11