Unlocking bioactive potential of peppermint seeds: fatty acids, phenolics, antioxidant and cytotoxic activity of supercritical CO ₂ extracts

BACKGROUND This is the first study aiming to investigate the yield and kinetics of supercritical CO 2 extraction of peppermint ( Mentha piperita L.) seeds, as well as to evaluate fatty acid and phenolic composition, antioxidant activity and cytotoxic properties against human lung adenocarcinoma (A549 cells) and normal fetal fibroblast (MRC‐5 cells) of the obtained extracts. Applied conditions of pressure and temperature for extraction were in the range of 10–30 MPa and 40–50 °C. RESULTS A significant increase in the yield was revealed at higher conditions of pressure and temperature. More than 80% of detected fatty acids belong to unsaturated fatty acids, with a predominant content of polyunsaturated fatty acids. With increasing pressure and temperature, the percentage of saturated and polyunsaturated fatty acids increased, whereas the amount of monounsaturated fatty acids decreased. The prenominal compounds in all tested samples were salvianolic acid, followed by rosmarinic acid and eriodictyol. Due to the highest content of individual phenolic compounds, optimal treatment for the phenolic compound extraction was 20 MPa and 40 °C. The sample extracted at the lowest pressure and the lowest temperature exhibited the most potent cytotoxicity against A549 cells. CONCLUSIONS Peppermint seeds represent a high‐value material that should be more extensively studied and encouraged for application in the food industry sector.