Abstract
Micro-algae are a rich natural source of highly valuable bioactive compounds like mycosporine-like amino acids (MAAs), scytonemin, carotenoids, vitamins, essential amino acids (EAAs), polyunsaturated fatty acids (PUFAs), minerals, polysaccharides, lectins, halogenated compounds, polyketides, agar-agar, alginic acid, carrageenan, enzymes and fibers. These compounds are involved in several defense strategies helping organisms to survive in various extreme environmental conditions, such as high salinity, high and low temperatures and deleterious solar radiation. Furthermore, they are promising biocatalysts and can be used in the field of “white biotechnology” to improve the sustainable production of metabolites. Micro-algae have the potential to become one of the most promising and innovative sources for novel food and functional products. They play a major role as functional ingredients for the enhancement of the nutritional value of foods and thus improving human health, wellbeing and quality of life. Micro-algal-derived bioactive compounds have UVscreening, anti-inflammatory, anti-microbial, antioxidant, antibiotics, immunosuppressants, anticancer and antiviral properties. These bioactive compounds have many biotechnological, industrial, pharmaceutical and cosmetic uses that are discussed in this chapter with their emerging techniques of harvesting to enhance their production on a commercial scale. The diverse metabolites from indigenous sources facilitate the promising effect, enabling researchers and pharmaceutical companies for the production of novel non-toxic and cost-effective medicines related to various applicable fields.