Recovery of bioactive and gelling extracts from edible brown seaweed Laminaria ochroleuca by non-isothermal autohydrolysis

Abstract

The non-isothermal autohydrolysis temperature impact of edible brown seaweed Laminaria ochroleuca was studied to recover high valuable compounds. Extraction yield was determined, above 80% was obtained at 220 °C. The maximal fucose content (17% d.b.) was attained at 180 °C, whereas the maximal sulphate was achieved at 160 °C, and phenolic and protein content at 220 °C. The maximum sulphated fucoidan content (41.38 g fucoidan/100 g extract) was obtained at 160 °C, whereas the maximum fucose oligosaccharides was obtained at 180 °C. The antioxidant capacity was equivalent to 32 mg Trolox/g dry extract produced at 220 °C. The milder processing condition was selected to study the potentiality of the precipitated alginate in terms of viscoelastic properties determined by rheology. Alginate extraction (14.94 g/100 g extract) was determined at 160 °C. The crude fucoidan fractions were tested at 25-500 μg/mL, showed up to 50% cell growth inhibition in four selected tumoral cell lines.

Keywords: Alginate; Antioxidant; Autohydrolysis; Cytotoxicity; Fucoidan; Laminaria ochroleuca.