On the stability of various highly branched isoprenoid (HBI) lipids in stored sediments and sediment extracts

The stability of various highly branched isoprenoid (HBI) lipids in sediments and sediment extracts stored under different conditions has been investigated over a period of about two years. Our data reveal an increased tendency for tri-unsaturated HBIs to undergo degradation compared to mono- and di-unsaturated counterparts, with sediments stored in plastic bags and exposed to light also showing a greater degradation extent than for samples stored in glass vials or those kept in the dark or at lower temperature. The composition of sediment extracts stored as dry material or as solutions, and at room temperature and in a refrigerator, exhibited no clear trends, but the extremely high variability in concentrations suggests that analysis of such stored extracts will likely lead to anomalous results.