Gas Chromatography Mass Spectrometry Analysis of Algae: The Fuel of Our Future

Gas Chromatography Mass Spectrometry Analysis of Algae: The Fuel of Our Future

Jerry Falwell Library, Lower Esbenshade Atrium

Microalgae has the potential to be used as an alternative to petroleum-based feedstock necessary for transportation fuels. Several companies are researching cost-effective ways to optimize algae growth and harvesting techniques in an effort to convert the lipid fraction of the algae biomass into various types of fuels. The ability to rapidly quantify the total lipid content of algae during the growth and harvesting processes is essential to evaluating the biofuel potential.

A GC/MSD (Gas Chromatography coupled with Mass Spectrometric Detection) method was developed for the separation, identification, and determination of lipids found in microalgae. Methyl esters of lipids are formed by direct acid-catalyzed hydrolysis, esterification, and trans-methylation using sulfuric acid in methanol, are injected on a GC column for separation and then detected by the mass spectrometer. Fatty acid methyl esters (FAME) are separated according to their boiling points, which is influenced by the number of carbon atoms and the degree of saturation.

Real-world samples, obtained from an algae company, were analyzed by GC/MSD and show distinct differences in the lipid profile between samples of low and high total lipid content. Samples with high content contained predominantly C16:0, C16:1, and C18:1 compounds. Efficiency of the conversion of lipids to FAMEs was evaluated relative to the C15 fatty acid internal standard. Quantification of FAMEs was performed relative to the C13 and C19 FAME internal standards. Algae companies make decisions about the optimal time to feed, transfer, and harvest an algae culture based on the analytical results of total lipid content in the samples.