oa Newly Detected Polar LIPIDS from Cultured Diatom Strains of North Pacific Ocean: Possible New Diatom Biomarker?

For better understanding of the biogeochemical cycle and palaeoceanographic reconstruction, biomarker analysis of diatoms typical to each individual ocean is necessary. However, until recently diatom biomarker analysis has been limited to Atlantic and Southern Ocean species and cultures. In the present study, we analyzed lipid biomarkers of culture samples of typical North Pacific diatom species and searched for new diatom biomarkers for palaeoceanographic reconstruction.

Key discoveries were the first detection of 24-norsterol from a cosmopolitan diatom Chaetoceros debilis and high abundance of 22-dehydrocholesterol from Neodenticula seminae. Also, 2 new compounds had been detected from Rhizosolenia hebetata. The significance and the paleoceanographic application of these findings will be discussed.