Recovery of bioactive complex from brown algae by alternative extraction approaches

Arctic brown algae are a valuable source of many bioactive compounds. The study presents an approach for obtaining a complex extract that combines the beneficial properties of all compounds instead of isolating narrow fractions, which is the focus of most seaweed processing technologies. The study examined the efficiency of conventional, ultrasonic, and microwave extraction with 40 % isopropanol as a non-conventional solvent. Ultrasonic pretreatment and swelling had a positive effect on the extraction of mannitol, pigments, and polyphenols. Microwave extraction resulted in extracts enriched with mannitol and polysaccharides. Strong positive correlations between radical scavenging, ferric reducing, and iron-chelating activities and the contents of pigments and polyphenols in the extracts were revealed. Thus, the proposed techniques, together with the specific solvent, show promise in replacing conventional solvents in plant biomass processing to obtain complex extracts. Due to their bioactive properties, they have promising potential for use in pharmaceuticals, veterinary medicine, and agriculture.