Triacylglycerol profiling of marine microalgae by mass spectrometry

We present a method for the determination of triacylglycerol (TAG)profi les of oleaginous saltwater microalgae relevant for the production of biofuels, bioactive lipids, and high-value lipid-based chemical precursors. We describe a technique to remove chlorophyll using quick, simple solid phase extraction (SPE)and directly compare the intact TAG composition of four microalgae species ( Phaeodactylum tricornutum , Nannochloropsis salina , Nannochloropsis oculata , and Tetraselmis suecica)using MALDI time-of-fl ight (TOF)mass spectrometry (MS), ESI linear ion trap-orbitrap (LTQ Orbitrap)MS, and 1 H NMR spectroscopy. Direct MS analysis is particularly effective to compare the polyunsaturated fatty acid (PUFA)composition for triacylglycerols because oxidation can often degrade samples upon derivatization. Using these methods, we observed that T. suecica contains signifi cant PUFA levels with respect to other microalgae. This method is applicable for high-throughput MS screening of microalgae TAG profi les and may aid in the commercial development of biofuels.