Lipid Profile Comparisons of Eight Edible Microalgal Species via UPLC–HRMS: Implications for the Industrial Development and Food Nutritional Applications of Microalgal Oil

Microalgae are promising future food sources with short growth cycles and high nutritional value. UPLC–HRMS analysis of eight edible microalgal species identified over 500 lipid molecular species, including glycolipids, phospholipids, sphingolipids, glycerides, and betaine lipids. Nannochloropsis gaditana exhibited the highest lipid content, with polar lipids accounting for 75.2% of the total lipids and ahigh eicosapentaenoic acid content of 29.9% of the total fatty acids, while Dunaliella salina was highly enriched in sphingolipids (50.3% of the total lipids), making the two species ideal industrial raw materials for glycolipid and sphingolipid production, respectively. These eight edible microalgal species were abundant in polyunsaturated fatty acids. In addition, a rare acylated derivative of sulfolipid, acyl-sulfoquinovosyldiacylglycerol (acSQDG), was identified in five microalgal species. Multivariate analysis confirmed lipid classes as effective biomarkers for discriminating the eight cross-phyla edible microalgal species. Overall, this study provides comprehensive lipidomic characterization of these eight microalgae and offers valuable guidance for the industrial development of microalgal oils.