Natural products from polar organisms: Structural diversity, bioactivities and potential pharmaceutical applications

Natural products have a huge value in pharmaceuticals industry as molecules or templates for discovery or further development of new drugs. It is predicted that, if the marine resources are explored fully, then we will have enough chemically diverse molecules to sustain us for the coming next century. For the discovery of new classes of natural products, polar organisms are emerging as a source of unknown magnitude because recent genetic based studies showed that the diversity of the polar region is much more than previously predicted. In order to survive in the cold, extreme and inhospitable environment conditions, polar organisms produce an array of unique metabolites which confer an advantage and offers protection from predation. Out of all the natural products reported from polar organisms, 38% of them showed bioactivity of pharmaceutical relevance. This high success percentage clearly illustrates the tremendous potential of the polar organisms as a source of new therapeutic agents for infectious and lifestyle associated diseases. We in this review describe the natural products discovered, isolated and characterized from the organisms (both prokaryotes and eukaryotes) found in the polar (Arctic and Antarctic) regions. Further, we discussed the problems encountered and solutions employed by the various researcher during natural product isolation from marine sources.