Isolation and identification by high resolution liquid chromatography tandem mass spectrometry of novel peptides with multifunctional lipid-lowering capacity

• Published in: Food research international 2018-09, Vol.111, p.77-86
• Main Authors: Prados, Isabel M., Marina, M. Luisa, García, M. Concepción
• Format: Article
• Language: English
• Subjects: HPLC-MS/MS; Hypolipidemia; Olive by-product; Peptides
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2018.05.009

This work describes the isolation, characterization, and identification by RP-HPLC-ESI-Q-TOF of novel peptides that interfere in the fat digestion and absorption mechanisms by multiple pathways. Peptides were ultrafiltrated and peptides in the most active fraction were further separated by semipreparative RP-HPLC. Nine different subfractions were obtained observing a high amount of peptides in subfraction F3. Peptides in subfraction F3 could simultaneously reduce the solubility of cholesterol in micelles and inhibit pancreatic cholesterol esterase and pancreatic lipase, even after a simulated gastrointestinal digestion. The identification of lipid-lowering peptides has been scarcely performed and when done, low selectivity or sensitivity of employed identification techniques or conditions did not yield reliable results. Separation and detection of peptides by RP-HPLC-ESI-Q-TOF-MS was optimized and most favorable conditions were employed for the identification of peptides using de novo sequencing. Ten different peptides with 4‐9 amino acids were identified. Main feature of identified peptides was the high acidity derived from a high presence of amino acids glutamic acid and aspartic acid in their sequences. [Display omitted] •A highly hypolipidemic peptide fraction has been obtained from olive seeds.•Lipid-lowering capacity of peptides was based on multiple hypolipidemic pathways.•RP-HPLC-ESI-QTOF conditions were chosen for the reliable identification of peptides.•Ten peptides were identified in the fraction with the highest lipid-lowering capacity.•All peptides showed high amounts of glutamic and aspartic acids and their amides.