Seaweed biomass is gaining industrial and economic momentum as a renewable feedstock for high-value products, including nutraceuticals, value-added chemicals and bioplastics. These organisms can be sustainably cultivated on an industrial scale, provide new opportunities for decreasing our dependency on fossil feedstocks, and potentially contribute to climate mitigation while reducing pressure on land resources. Seaweed generally possesses a high polysaccharide content, making it an alternative source to crop plants for bioplastic production. Polysaccharides like alginate, carrageenan, ulvan, fucoidan and laminarin are good candidates as bioplastic components due to their compatibility with various matrices and film-forming abilities. A wide range of applications are already demonstrated for these polysaccharides in biomedical areas, food packaging, functional foods, nutraceuticals and the pharmaceutical industry. Composites and blends of these polysaccharides with other polymers, additives, and fillers have been reported as a solution to improve the mechanical properties and, in some cases, to combine desired attributes strategically. This review examines seaweed-derived polysaccharides, their extraction and characterization techniques, application and performance as bioplastics, blends and composites, and material characteristics.
