Bioprospecting seaweed derived bio-oil as a marine biofouling mitigating agent

Mitigating marine biofouling using marine resources has become a research hotspot as it is considered an environmentally friendly approach. Hence, this study investigated the biofilm mitigating property and antifouling activity of bio-oil extracted from the pyrolysis of seaweed biomass. The bio-oil inhibited up to 73-80% of biofilm and extracellular polymeric substance (EPS) formation of the predominant marine microfoulers <i>Nitratireductor kimnyeongensis</i>, <i>Nitratireductor aquibiodomus</i> and <i>Stutzerimonas stutzeri</i>. Gas chromatography-mass spectrometry (GC-MS) analysis of the bio-oil identified that 13-Docosenamide (<i>Z</i>) is a prominent compound that accounts for about 27.42% of the total bio-oil composition which might be responsible for its antibiofilm property. The bio-oil was further formulated into antifouling paint equivalent to the consistency of traditional antifouling paints and coated on titanium plates. The water contact angle results showed that bio-oil and antifouling paint exhibit hydrophilic surfaces, effectively reducing bacterial attachment. Scanning electron microscopic analysis revealed that the anti-fouling paint coated on titanium plates against mixed species of microfoulers significantly reduced biofilms. Molecular docking of 13-Docosenamide (<i>Z</i>) against the mussel adhesive foot protein of <i>Perna viridis</i> (Pvfp-5b) exhibited favorable binding scores, indicating that it may reduce the bio-adhesion of macrofoulers to the substrate.