A number of studies on the development of a variety of extraction techniques to produce algal extracts have been reported. In this chapter, special attention is paid to the algal extracts obtained by the enzymatic and chemical hydrolysis (with the use of organic and inorganic solvents). In addition, a review of the different pretreatment methods of the biomass before extraction process is shown. The advantages and disadvantages of the various methods of algal extracts production are discussed.
Algae are known to produce a variety of bioactive compounds (e.g., polysaccharides, phenolic compounds, proteins, lipids, carotenoids) that possess biological activities of potential medicinal, agricultural, and cosmetic value. Therefore, antioxidant, antimicrobial, antiviral, anti‐inflammatory properties of seaweed extracts are discussed. The application of algal extracts obtained with the use of distilled water in modern agriculture (biostimulants, bioregulators) is also analyzed. The obtained seaweeds extracts are biodegradable, nontoxic, nonpolluting, and nonhazardous to humans, animals, and birds. Therefore, these can be applied to different branches of the industry.