Exploring the lipid profiles of three marine fungi

Three species of marine fungi from the Ascomycota phylum were previously isolated from oil-soaked sand patties collected from Gulf Coast beaches following the 2010 Deepwater Horizon oil spill. These fungi have been shown to degrade crude oil, however, little is known about the mechanism of oil degradation or the extent to which oil is incorporated into fungal biomass. This study focuses on determining the lipid profile of the three marine fungi to quantify biomarkers of interest that could be used in future experiments to determine the uptake of oil. In this instance, the uptake of oil would be determined by measuring the carbon isotopic composition of these fungal biomarkers relative to the carbon isotopic composition of the available carbon sources. In this study, the three species of marine fungi were cultivated in the lab before drying and extracting with a mixture of methanol and dichloromethane (2:1 ratio). The lipid extract was then subjected to silica gel chromatography and separated into three fractions by eluting sequentially with dichloromethane, acetone, and methanol to obtain non-polar, neutral, and polar fractions respectively. All fractions were derivatized prior to analysis via gas chromatography mass spectrometry. Preliminary analysis revealed the presence of phospholipid fatty acids (PLFA), ergosterol and pyrrolo[1,2-a]pyrazine-1,4-dione, a potential antimicrobial. Quantification of these biomarkers and further analysis of additional biomarkers of interest is ongoing.