Abstract: In this study, a three-stage sequential subcritical solvent extraction procedure using butane, acetone, and ethanol was developed to extract lipids from Antarctic krill oil. Additionally, lipidomics was applied to characterize the lipid profile and enrichment characteristics of each extract. The results indicated that the total lipid yield obtained by the extraction procedure was 95.76%. Lipidomic analysis revealed that the subcritical butane fraction was primarily rich in triglyceride-type saturated fatty acids (42.62%), including triacylglycerols (14:0_16:0_18:1). The acetone fraction exhibited a strong enrichment capacity for triglyceride-type monounsaturated fatty acids (30.93%) as well as bioactive components including astaxanthin. On the other hand, the ethanol phase efficiently enriched phospholipid-type n-3 polyunsaturated fatty acids (39.92%), including phosphatidylcholine (20:5_22:6). This extraction process successfully achieved the differential enrichment of distinct lipid components, thereby providing a technical reference and scientific basis for the subsequent elucidation of the functional characteristics of specific lipid components in Antarctic krill oil and the development of personalized products.

Key words: Antarctic krill oil; subcritical; sequential extraction; lipidomics; compositional analysis