Abstract
Marine cyanobacteria are oxygenic, gram-negative nitrogen-fixing
photosynthetic prokaryotes in different environments. It is a universal organism present
in aquatic and terrestrial and also extensively scattered in extreme habitats such as hot
springs, deserts and glacial environments. Growing concerns over disease outbreaks
and other environmental concerns require alternative ways that are economically
viable, sustainable, as well as feasible. Recently, cyanobacteria have achieved much
consideration because of their potential relevance in various fields, including
aquaculture, wastewater treatment, food, fodder, and the production of secondary
metabolites, including polysaccharides, vitamins, toxins, enzymes and pharmaceuticals;
they also secrete important novel bioactive antimicrobials including antibacterial,
antifungal and anti-viral compounds. The emergence of antimicrobial resistance among
pathogenic microbes against common antibiotics imposed the search for new
antimicrobial agents from natural sources. Various features of cyanobacteria, including
their ability to produce novel antimicrobials, make them suitable candidates for their
exploitation as a natural source. Hence, this chapter presents an overview of marine
cyanobacterial features, antimicrobials isolated from marine cyanobacteria, as well as
the mode of action. Among the known cyanobacterial bioactive compounds, many are
pharmacologically important and hold immense potential for drug development at the
clinical level