Chemical fingerprinting of algaenans using RuO4 degradation

The freshwater green microalgae, Oocystus solitaria Wittrock f. maior Wille, Pediastrum braunii Wartmann, Pediastrum kawraiskyi Schmidle, Sorastrum spinulosum Nägeli and Coelastrum reticulatum (Dangeard) Senn were investigated with respect to the presence of algaenan and the corresponding RuO4 chemical fingerprint. All species, with the exception of O. solitaria, were shown to possess a cell wall resistant toward strong acid and base treatment. By analysis of the RuO4 chemical degradation products from these materials a molecular fingerprint was obtained having similar features to the RuO4 fingerprints of Tetraedron minimum, Scenedesmus communis and Pediastrum boryanum algaenans reported in earlier studies. Previously it had been shown that these RuO4 fingerprints could also be obtained from ancient sediments, indicating the presence of algaenan as part of the organic matter. The results from this study show that the chemical composition of algaenans is possibly a chemotaxonomic feature and can be used to chemically explore the algal contribution to sedimentary organic matter on a family level. Furthermore, it illustrates that the use of RuO4 degradation combined with gas chromatography is a suitable analytical tool for the purpose of chemical fingerprinting of algaenans.