Marine algae: An Introduction, Food value and Medicinal uses

Seaweeds offer a wide range of therapeutic possibilities both internally and externally. The term seaweeds refer only to macrophytic marine algae, both wild and cultivated, growing in saltwater. Botanically, seaweeds are classified as green, brown, or red. A particular seaweed’s placement in one of these groups is determined first by its photosynthetic pigments, then its reproductive mode, then its micro and macro morphologies, and finally by its phycopolymers. In the last three decades the discovery of metabolites with biological activities from macroalgae has increased significantly. However, despite the intense research effort byacademic and corporate institutions, very few products with real potential have been identified or developed. Substances that currently receive most attention from pharmaceutical companies for use in drug development or from researchers in the field of medicine-related research include: sulphated polysaccharides as antiviralsubstances, halogenated furanones from Delisea pulchra as antifouling compounds, and kahalalide F from a species of Bryopsis as a possible treatment of lung cancer, tumours and AIDS. Other substances such as macroalgal lectins, fucoidans, kainoids and aplysiatoxins are routinely used in biomedical research and a multitude of other substances have known biological activities. Fucus vesiculosus is a brown seaweed that grows on the northern coasts of the Atlantic and Pacific oceans and the North and Baltic seas. This species is often included in kelp preparations along with other types of seaweed. As an herbal medicine, seaweed has been used for traditional cosmetics, treatments for cough, asthma, hemorrhoid, boils, goiters, stomach ailments, and urinary diseases, and for reducing the incidence oftumors, ulcers, and headaches.