Abstract
The extracellular polymeric substances (EPS) produced by the bacteria associated with the gastropod Turbo sp. were isolated and screened for antibacterial activity against biofilm-forming bacteria. EPS of five out of 13 strains showed inhibitory activities in the antibacterial assay. Furthermore, the antibiofilm and antifouling activity of the most active EPS isolated from the strain KT1 was studied using various in vitro and in vivo bioassays. Results revealed that EPS significantly inhibited the growth and biofilm formation of bacteria. Furthermore, the antifouling coating developed with bacterial EPS considerably reduced the recruitment of fouling organisms on coated surfaces submerged in the seawater. The functional groups present in EPS, characterized by strong activity, were analyzed using FT-IR and the spectrum showed the presence of alcohol, amines, carboxylic acid and esters. The bacterium responsible for the production of bioactive EPS was identified as Pseudomonas aeruginosa, using the 16S rRNA gene. Since the findings of this study revealed the antibiofilm and antifouling activities of EPS, further long term field tests and characterization of the bioactive compound of the EPS could lead to the development of eco-friendly antifouling coating.