Characterisation and anti-biofilm activity of extracellular polymeric substances from Oceanobacillus iheyensis

Oceanobacillus iheyensis BK6, isolated from a marine natural biofilm, produced approximately 400 mg L−1 extracellular polymeric substances (EPS). FTIR analysis of the EPS revealed different functional groups (halide groups, uronic acid and saccharides). The GCMS showed that the extracellular polysacchrides comprised of mannose (47.78%), glucose (29.71%) and arabinose (22.46%). The molecular mass of the EPS was about 2.14 × 106 Da. It was thermally stable and showed pseudoplastic rheology and emulsifying activity (66.47%). The EPS exhibited antibiofilm activity against a pathogenic strain of Staphylococcus aureus. This is the first report on the characterisation of EPS from the genus Oceanobacillus. The high viscosity, emulsifying properties and antibiofilm activity of EPS make it suitable for potential pharmaceutical and industrial applications.