A Fast and Green Extraction Method for Berry Seed Lipid Extraction Using CO 2 Expanded Ethanol Combined with Sonication

In this work, a combination of sonication and carbon dioxide expanded liquid extraction (SA-CXLE) is used for the first time for the extraction of lipids from berry seeds. Three solvents (ethanol, methanol and ethyl lactate) are screened for the best recoveries of total lipids. Ethanol is selected due to its efficiency, greenness and sustainability. The effects of operation variables including temperature, time and CO2 molar fraction on extraction performance are examined using a response surface methodology. The optimum conditions were found at 0.37 molar fraction of CO2 in ethanol, a temperature of 52 °C and an extraction time of 7 min for two cycles. The SA-CXLE method extracts 323 ± 38 mg g−1 seed compared to 194 ± 23 using a conventional solid-liquid extraction. SA-CXLE is successfully applied to profile lipids from gooseberry, blackcurrant, chokeberry, red currant, and rowanberry seeds. More than 17 lipid classes are characterized and identified. Gooseberry shows the highest amount of oil of 352 mg g−1 seed. Practical Applications: The developed method provides a fast, efficient and simple approach to extract and profile lipids using a combination of green solvents. Total lipid content and fatty acids composition of the berry seeds are essential information in pharmaceutical, cosmetic, food and nutritional applications.