Ultrasound-Assisted Extraction of Biopolymers from Ascophyllum nodosum Brown Seaweeds: Bioactivity and Enzyme Inhibition of Phlorotannins assessment

Abstract

Ascophyllum nodosum seaweeds was used as source of biopolymers. The ultrasoundassisted extraction was used to obtain extracts with high content of bioactive compounds with high antioxidant and enzyme inhibition activities. The physicochemical characterization of these extracts showed a high content of phlorotannins along with other substances (carbohydrates and uronic acids), being necessary subsequent purification steps. By means of gel chromatography and dialysis, extracts with an improved bioactivity were obtained. Extracts with the highest bioactivities were significant inhibitors of αamylase and αglucosidase digestive enzymes. Finally, alginates with modulated properties were also obtained improving the integral use of the seaweeds, after the extraction of phlorotannins. Results indicated that extracted biopolymers from Ascophyllum nodosum can be employed in glutenfree foods for celiac people and functional formulations.