Seaweeds have an extremely numerous of species in the world and been able to be divided into several developmental systems. Broadly, three types of seaweeds can be defined according to their color: brown seaweeds, green seaweeds, and red seaweeds. Thousands of years ago, mankind used seaweeds as food and medicine. Seaweed extracts are gaining increasing attention due to their unique composition and the potential for widespread use in industry. A variety of novel (green) extraction techniques have been devised for converting seaweed biomass into seaweed extracts, such as enzyme-assisted extraction (EAE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), supercritical fluid extraction (SFE), and ultrasound-assisted extraction (UAE), which are capable of extracting seaweeds’ biologically active compounds without causing degradation. Seaweed extracts contain compounds, such as carbohydrates, proteins, minerals, oils, fats, and polyunsaturated fatty acids and abundant bioactive compounds, such as antioxidants, pigments, and sulfated seaweed polysaccharides (SWP), as well as antibacterial, antifungal, anti-inflammatory, antioxidation, antitumor, antiviral, and hypolipidemic effect. The purpose of this article is to describe the antioxidant activity of SWP of brown seaweeds, green seaweeds, and red seaweeds by novel assisted extraction.
Part of the book: Solubility of Polysaccharides