**2.2 Microalgae and nutraceuticals**

The market for nutraceuticals extracted from microalgae is dominated, if not composed majorly of products from around four species of microalgae—*Spirulina, Chlorella, Haematococcus,* and *Dunaliella*. Other species that are involved in nutraceutical production include *Odontella aurita, Schizochytrium sp, Phaeodactylum,* etc.

There are numerous essential compounds of interest (as show in **Figure 1**) that are and can be produced by means of these microalgae. These compounds are then further used for production of their respective functional and nutraceutical feed. Some of the important nutrients include

	- These are defined as fatty acids with more than 18 carbon atoms and at least one double bond in their chemical structures. These can be synthesized as food supplements and are essential nutrients for humans and animals that are not produced internally. They have been recorded to have antimicrobial, antiinflammatory, antioxidant properties.

functions and are either incorporated into compounds or stay in their elemental state.


Furthermore, sterols have been linked to anti-inflammatory and anti-atherogenicity, anticancer, and anti-oxidation actions, as well as protection against nervous system illnesses such as autoimmune encephalomyelitis, amyotrophic lateral sclerosis, and Alzheimer's disease.
