Biotechnology and Bioinformatics (1+1)

5.1.4. Marine microalgae

Marine microalgae are relatively unexploited but are rich resources for bioactive compounds. Toxins initially isolated from fish or shellfish were found to originate from microalgae, especially dinoflagellates. These toxins are useful tools to investigate the structure and function of ion channels on cell membranes or to elucidate the mechanism of tumor promotion based on their specific inhibitory action against protein phosphatases.

The number of antifungal or antitumoral substances of microalgal origin is rapidly increasing. More importantly, structural similarities have been found between many bioactives found in marine invertebrates and those in freshwater blue-green algae. The similarities point to a great potential of marine blue-greens, the least explored resource, for producing bioactive compounds of medicinal value.

Microalgae are significant resource for bioactive metabolites, particularly cytotoxic agents with applications in cancer chemotherapy.

• From the marine microalgae such as from the blooms of Phaeocystis sp., antibiotic substances were listed. Phaeocystis pouchetii is reported to produce chemicals such as Acrylic acid, which constitutes about 7.0% of the dry weight. The antibiotic substances thus produced are transferred throughout the food chain and found in the digestive tract of Antartic penguins.
• Production of ß carotene and vitamins by the halotolerant alga Dunaliella sp., is documented.
• Microalgae produce incredibly potent alkaloidal neurotoxins such as saxitoxin and polyketide neurotoxins such as the brevetoxins.