Jump to ContentJump to Main Navigation
Chemical Biomarkers in Aquatic Ecosystems$
Users without a subscription are not able to see the full content.

Thomas S. Bianchi and Elizabeth A. Canuel

Print publication date: 2011

Print ISBN-13: 9780691134147

Published to Princeton Scholarship Online: October 2017

DOI: 10.23943/princeton/9780691134147.001.0001

Show Summary Details
Page of

PRINTED FROM PRINCETON SCHOLARSHIP ONLINE (www.princeton.universitypressscholarship.com). (c) Copyright Princeton University Press, 2022. All Rights Reserved. An individual user may print out a PDF of a single chapter of a monograph in PRSO for personal use.date: 07 July 2022

Lipids: Alkenones, Polar Lipids, and Ether Lipids

Lipids: Alkenones, Polar Lipids, and Ether Lipids

(p.207) 11. Lipids: Alkenones, Polar Lipids, and Ether Lipids
Chemical Biomarkers in Aquatic Ecosystems

Thomas S. Bianchi

Elizabeth A. Canuel

Princeton University Press

This chapter focuses on several classes of polar lipids, including alkenones, which are di-, tri-, and tetra-unsaturated long-chain ketones. These compounds are produced by a restricted number of species of prymnesiophyte algae (coccolithophorid alga Emiliania huxleyi), living over a wide temperature range. Prymnesiophytes are able to live under different temperature regimes because they are able to regulate the degree of unsaturation of these compounds; as ambient water temperature decreases, unsaturation increases. Long-chain ketones are more stable than most unsaturated lipids and can survive diagenesis. Because of these properties, alkenones have been used widely as paleothermometers. Paleoclimate studies of continental environments have been hampered by the lack of a useful temperature proxy. Glycerol dialkyl glycerol tetraethers (GDGTs) occur ubiquitously, including sites where alkenones are not produced due to the absence/low abundance of alkenone-producing algae. The TEX86 index, based on the number of cyclopentane rings in the GDGTs, provides a useful paleotemperature index for lakes and other sites where alkenones are not produced. The analysis of intact polar molecules is also becoming more widespread with the advent of liquid chromatography mass spectrometry techniques.

Keywords:   polar lipids, long-chain ketones, biomarkers, prymnesiophyte algae, alkenones

Princeton Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.

Please, subscribe or login to access full text content.

If you think you should have access to this title, please contact your librarian.

To troubleshoot, please check our FAQs , and if you can't find the answer there, please contact us.