Microalgae mostly contain triglycerides as carbon storage; these are composed of short-carbon-chain saturated fatty acids which are suitable for biodiesel production.

Certain microalgae can also be used as an alternative source for dietary fatty acids such as:

• Omega-3 unsaturated fatty acids
• Eicosapentaenoic acid (EPA)
• Docosahexaenoic acid (DHA)
• Omega-6 unsaturated fatty acids
• Linolenic acid
• Arachidonic acid 

Omega-3 fatty acids are essential fatty acids, which cannot be synthesized by human beings and must be obtained from the diet. Dietary supplement of ALA acts as precursors for EPA and DHA biosynthesis in humans. DHA is one of the major fatty acids of the brain and retina and is considered responsible for visual and cognitive development. EPA and DHA have been shown in some studies to aid in the prevention of coronary heart disease, stroke, hypertension, dementia, Alzheimer’s and depression. A common source of these fatty acids has been wild harvest ‘Fish oil’ and ‘Krill oil’ until recently. Nowadays, these fatty acids have been sustainably produced from heterotrophic microalga Crypthecodinium cohnii and photoautotrophic microalgae Phaeodactylum tricornutum and Nannochloropsis sp. Thus, an alternate “vegetarian source” for these fatty acids has been recently developed, and there is a growing demand for sustainably produced omega fatty acids.