A comparative study of fossil- and extant algaenans using ruthenium tetroxide degradation

In this study the chemical structure of algaenans isolated from the freshwater algae Tetraedron minimum, Pediastrum boryanum and Botryococcus braunii are compared with their fossil counterparts by means of RuO4 oxidation. The results show that the algaenans investigated are preserved in sediments with only minor structural alterations. However, product mixtures from RuO4 degradation of the fossil algaenans exhibit a broader distribution of oxidation products than freshly isolated algaenans indicating that the fossil biopolymers contain a greater proportion of ether cross-links, which maybe an effect of diagenetic alteration or different algal strains. Despite these differences, fossil algaenans can still be recognised chemically on the basis of the specific RuO4 oxidation products, even after 50 Ma of sediment burial.