Microbial exopolysaccharides from extreme environments

Polysaccharides and primarily microbial polysaccharides represent a class of important products of growing interest for many sectors of the industry. Although many bacteria produce exopolysaccharides, continuation in looking for new polysaccharide-producing microorganisms is still promising. Extreme environments uch as hot springs, microbial mais, habitats of archaebacteria and hydrothermal vents suggest themselves for further studies. Deep-sea hydrothermal vents discovered for 20 years now, offer a new source of a large variety of fascinating microorganisms well adapted to these extreme environments. This great bacterial diversity could be a real source of new strains possessing an ability to secrete under laboratory conditions innovative molecules including exopolysaccharides. Screening of 500 isolates recovered from different oceanographic cruises led to the discovery of 30 isolates able to produce unusual extracellular exopolysaccharides. Owing to their specific rheological properties, biological activities metal binding capabilities and chemical composition these exopolysaccharides are expected to find applications in the near future.