MicroMarin is a library of Brazilian marine bacteria containing 1,500 isolated strains of invertebrate and marine sediment  from the Brazilian coast and oceanic islands. Most of the already cataloged and cryopreserved strains are actinomycetes, a group of Gram-positive bacteria highly promising as producers of cytotoxic and antibiotic molecules. Extracts from most strains have already been produced and 15% presented cytotoxicity against tumor cells in culture. Molecules with biological activity are the subject of additional studies to elucidate the mechanisms of action in tumor cells.