Pelagic Sargassum as a Source of Micro- and Nanocellulose for Environmentally Sustainable Plastics

One of the most critical environmental problems to solve is the plastic waste accumulation, due to the difficulty to biodegrade them, besides the release of toxic components, for humans and animals, produced during their degradation. One option to reduce this problem is related to the use of eco-friendly raw materials, and in this regard, many biopolymers from different sources have become a good option, being the algae, and in specific, the pelagic Sargassum is one of them. The main advantage of this alga comes from its chemical composition, as it contains alginate that is a common material to make environmentally friendly plastics, besides its high concentration of lignocellulosic materials, from which it is possible to produce nanocellulose. Another possible useful component reported from pelagic Sargassum is fucoidan, a sulfated carbohydrate with cytotoxic activities against bacteria, giving rise to the possibility of generating a new kind of functional plastics, helping to reduce the problem promoted by Sargassum in the Caribbean Sea. In this chapter, recent information about the extraction of compounds from pelagic Sargassum as alginate, nanocellulose, and fucoidan, for applying in the elaboration of bioplastics with functional activities, will be discussed.