New drugs from marine natural products

Marine organisms are an excellent source of novel chemicals and enzymes, which include a variety of primary and secondary metabolites with significant biological activities. Variations within species can produce differences in compounds and in their concentrations in different marine environments. Therefore, it is essential to study organisms from various locations.

There is a constant need for new chemotherapeutics for treating human disease, particularly in the anti-infective, anticancer and anti-inflammatory fields. Therefore, the EU-funded MAREX project investigated new compounds in natural products from marine organisms. The project involved researchers from all over the world who have collected marine organisms from seas and oceans in Asia, Europe and South America.

The consortium created a project database, established logistics protocols and conducted data collection covering e.g., sampling, processing, cultivation and biological testing procedures and results. Researchers also developed methods and techniques for the cultivation of several algae and bacterial species. In addition, species of algae, cyanobacteria and marine invertebrates were sampled and several interesting chemical compounds were isolated and characterized from extracts for further study.

Over 600 marine organisms were collected from the Atlantic, Indian and Pacific Oceans and from the Adriatic, Arabian, Baltic and Mediterranean Seas. These organisms included dinoflagellates and other microalgae, cyanobacteria, sponges, sea anemones, tunicates and sea cucumbers.

Samples with significant antimicrobial activity against bacteria and fungi were identified. This included combating the growth of methicillin-resistant Staphylococcus aureus. Scientists also identified samples active against other bacteria such as Vibrio cholerae, some strains of which cause the disease cholera.

The project also contributed to the design, synthesis and evaluation of around 400 new synthetic compounds based on natural products involved in alleviating cancer, bacterial infection and inflammation. Natural product extracts were also studied for their potential growth regulating activity against higher plants and microalgae. For example, extracts from the cyanobacterial species Nodularia were shown to control the growth of microalgae.

MAREX results confirmed the importance of using marine natural products as a starting point for the discovery of new drugs. The work helps to increase availability of bioactive compounds of marine origin and has strengthened the potential of the European pharmaceutical and chemical industry in drug discovery.