Functional Properties of Seaweed on Gut Microbiota

Since it has been linked to a variety of advantages for human health, seaweed consumption has grown in Western nations. Seaweeds are typically divided into three phylum-level groupings based on their natural pigmentation: red seaweed (Rhodophyta), brown seaweed (Phaeophyta), and green seaweed (Chlorophyta), with brown seaweed being the most prevalent. These seaweeds as, explained in the previous chapter, contains different bioactive compounds, not only due to their chemical nature, but also because marine algae produce a wide range of different metabolites to survive in extreme marine environments. Among these compounds are polysaccharides, polyunsaturated fatty acids, different antioxidants compounds as phlorotannins and bioactive peptides. These components have shown their potential preventive effects against cardiovascular diseases, hypertension, obesity, diabetes and even cancer. In the last years, biomedical research has led to advances in the knowledge of the gut microbiota showing that it acts in a symbiotic way with the host and playing a fundamental role in health and disease. It is clear is that a balanced microbiota is fundamental in the prevention of these pathologies. Therefore, the scientific community is in the search of new strategies or therapies for improving the composition of the gut microbiota. One of these strategies is the use of functional foods or ingredients as modulators. In this sense, the seaweed, and their components, especially, the polysaccharides, which are not absorbed in the small intestine, have arisen as potential prebiotics since these compounds seems to exert a positive effect in the gut microbiota in in vitro and in vivo animal studies. The present chapter outlines current knowledge about the effect of seaweed and seaweed derived compounds as potential modulators of the gut microbiota.