Bioactive Compounds from Nostoc Species

Recently microalgae have become commercially important because of novel compounds of potential medicinal value. Nostocspecies are producers of structurally and functionally diverse natural biological activities such as antibacterial, antiviral, anticancer, antitumor, algicide, antifungal, enzyme inhibiting, immunostimulant, antiplatelet aggregation, cytotoxic and antiplasmodium activities. Most of the isolated substances from the alga belong to groups of hydrocarbons such as phytane; lipids such as sterol, esters, waxes and free sterols; fatty acids such as dioic acids; derivatives of amino acids such as indole-3-acetic acid and anatoxin A; terpenoids and aromatic compounds such as diterpenoid and anthraquinone; boron-containing macrocycles such as borophycin; arsenolipids such as dimethylarsenic acid; mycosporine-like amino acids such as shinorine and scytonemin; lipopeptides such as cryptophycin-1 and polyketides and several carotenoids; amides, alkaloids, peptides, monosaccharides and polysaccharides. Some extracellular metabolites secreted by cyanobacteria function as toxins or allelochemicals. Apart from these cytotoxic metabolites (e.g. nostocyclophanes, borophycin, elastase inhibitors, antitumor, antifungal agent, antiviral indolocarbazoiles) they produce antimitotic compounds. This article provides an overview of bioactive compounds produced by Nostocspecies.