Antifouling properties of marine bacteriocin incorporated epoxy based paint

Bacteriocin isolated from five marine biofilm forming bacteria viz. Pseudomonas aeruginosa, Bacillus sp., Micrococcus sp., and Flavobacterium sp., were evaluated for their antibacterial activities against each other. Among them, the secondary metabolites isolated from Pseudomonas aeruginosa exhibited maximum antibacterial activity. When the pure strains of P. aeruginosa and Micrococcus sp. were co-cultured in liquid nutrient broth, the P. aeruginosa outcompeted the population of Micrococcus sp. Further, a field study was conducted to show the antifouling activity of Pseudomonas aeruginosa biofilm, developed on stainless steel (SS) coupons in natural seawater for 60 days. Initiation of macrofouling was evident on the control coupon within 30 days of exposure; whereas no such incidence of macrofouling initiation could be observed on the coupon that was pre-biofilmed by P. aeruginosa even up to 60 days. Similarly, the bacteriocin incorporated epoxy based paint formulation exhibited antifouling property for 3 months. The bacteriocin of P. aeruginosa which exhibited antifouling activity was characterised using GC-MS and identified the active compounds.