Supercritical CO2 Extraction of Fatty Acids, Phytosterols, and Volatiles from Myrtle (Myrtus communis L.) Fruit

Background: Myrtle (Myrtus communis L.) is a coastal Mediterranean aromatic medicinal plant rich in essential oil components, flavonoids, and phenolic acids. Studies highlight the potential health benefits of myrtle bioactive compounds with antioxidant and antiproliferative properties. Since limited research exists on myrtle fruit's lipid fraction, the aim of this study was to apply supercritical CO2 extraction to obtain bioactive compounds from myrtle berries focusing on the fatty acids, sterols, and essential oils. Methods: The optimization of the supercritical CO2 extraction of myrtle fruit using CO2 as solvent was carried out using the response surface methodology with Box-Behnken experimental design. The following conditions were tested: temperature (40, 50, and 60 degrees C), pressure (200, 300, and 400 bar), and flow rate (20, 30, and 40 g min-1) on the yield of lipid extract as well as on the yield of fatty acids, phytosterols, and volatiles present in the extract and constituting its bioactive potential. Results: In the extracts examined, 36 fatty acids, 7 phytosterols, and 13 volatiles were identified. The average yield of the extract was 5.20%, the most abundant identified fatty acid was essential cis-linolenic acid (76.83%), almost 90% of the total phytosterols were beta-sitosterol (12,465 mg kg-1), while myrtenyl acetate (4297 mg kg-1) was the most represented volatile compound. The optimal process conditions obtained allow the formulation of extracts with specific compositions.