Microalgae are at the bottom of the food chain. They are microscopic and made of one cell. They are found in fresh and salt water. They absorb water and carbon dioxide, which are converted by sunlight into organic compounds (photosynthesis). They grow in a wide range of physical conditions and have fast growth rates. Algae are high in protein and polyunsaturated fatty acids.
Marine algae contain carotenoids, which belong to a class of chemicals called terpenoids (natural pigments). The light-absorption properties of carotenoids are essential for photosynthesis. Zeaxanthin, lutein, astaxanthin, and fucoxanthin, also, are carotenoids. These are antioxidants, relieving oxidative stress. Carotenoids are important for prevention and treatment of degenerative diseases.
Industrial uses of carotenoids are for food and health. Natural beta-carotene is desirable because natural properties are not duplicated in the synthetic form of beta-carotene. Antioxidants, such as beta-carotene, are used as food additives to prevent oxidation. Carotenoids are strong dyes and extracts of chlorella algae are used as pigments. Beta-carotene is used as pro-vitamin A (retinol) in multivitamins and healthy foods. Carotenoids stimulate the immune system and several studies of beta-carotene from Dunalliela sp. show that it lowers the incidence of cancer and degenerative disease.
High temperatures and extreme pH levels favor production of lutein. Astaxanthin production from Haematococcus sp. is increased by “adverse environmental conditions.” Astaxanthin can be produced outdoors with proper nitrate and mineral conditions. Beta-carotene comes from Dunaliella salina. Iron and the oxidative stress it produces play a role in commercial cultivation of beta-carotene.
CONCLUSION: The need for large scale production of carotenoids has been met by cultivation of microalgae in large quantities.
To read the author’s abstract of the article, click on the title of the article. Then, to read the full article, click on the free full text icon.