Photochemical alteration of 3-oxygenated triterpenoids: Implications for the origin of 3,4-seco-triterpenoids in sediments

Authors

Bernd R.T. Simoneit, Department of Chemistry, Oregon State University and Southeast Environmental Research Center, Department of Chemistry and Biochemistry, Florida International UniversityFollow
Yunping Xu, Southeast Environmental Research Center, Department of Chemistry and Biochemistry, Florida International UniversityFollow
Renato R. Neto, Southeast Environmental Research Center, Department of Chemistry and Biochemistry, Florida International UniversityFollow
Joshua B. Cloutier, Southeast Environmental Research Center, Department of Chemistry and Biochemistry, Florida International University
Rudolf Jaffe´, Southeast Environmental Research Center, Department of Chemistry and Biochemistry, Florida International UniversityFollow

Abstract

The reactivity of higher plant derived 3-oxy-triterpenoids to sunlight was investigated using a series of pure reference standards both under simulated and real solar exposure. The majority of the exposed compounds showed reactivity to light, particularly to simulated sunlight and among others generated seco-derivatives. While photochemical processes have been suggested for the formation of such compounds, their abundances in some sediments have often been assumed to be the result of diagenetic reworking of parent triterpenoids. Analyses of mangrove leaf waxes, an important known source of taraxerol in coastal ecosystems, showed the presence of the 3,4-seco-derivative dihydrolacunosic acid, which could represent an important biotic source for des-A-triterpenoid precursors to such sediments, and is unrelated to aquatic organic matter diagenesis.

Comments

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Recommended Citation

Simoneit, B.R.T., Y. Xu, R. Neto, J. Cloutier, R. Jaffe. 2009. Photochemical alteration of 3-oxygenated triterpenoids: Implications for the origin of 3,4-seco-triterpenoids in sediments. Chemosphere 74: 543-550.