Unlocking functional lipid ingredients from algae by food-grade biosolvents and ultrasound-assisted extraction for nutritional applications

Algae are a sustainable source of healthy and functional lipids. The production of extracts suitable for food and nutraceutical industries requires food-grade solvents, which may have low lipid extraction yield and/or purity. This work aimed to assess the efficiency of biosolvents ethanol (E) and ethyl acetate (EA) in obtaining food-grade lipid ingredients from an algae blend, Fucus vesiculosus, Ulva sp., and Chlorella vulgaris, in comparison with the Folch method. Ultrasound (UAE) was assayed to enhance the biosolvent extraction. The results showed that the different extraction approaches can significantly influence the extraction yield, lipid purity, and lipid composition, including fatty acid (FA) content. EA and EA+UAE produced high lipid purity (>74%) extracts with high polyunsaturated FA (≤77.5%) and n-3 FA (≤74.4%) contents, despite the lower extraction yield. E+UAE may be used to obtain lipid-rich ingredients from algae blend (57%) and C. vulgaris (91%). All extracts showed anti-inflammatory and antioxidant properties. This study provides relevant information for the production of food-grade lipid ingredients from algae.