English abstract
In the current study, chitosan coatings were fabricated on plastic substrata and investigated for their antifouling activities. Scanning Electron Microscopy (SEM) and water contact angle measurement (WCA) of the fabricated chitosan films showed smooth and hydrophilic surface with WCA below 60°C. In the first experiment, chitosan coating on plastic substrate showed 88% reduction in settlement of bryozoan Bugula neritina larvae compared to the control after 3 hours incubation at dark conditions with no larval mortality. In the second experiment, the antimicrobial activity of chitosan was evaluated by coating plastic panels with the prepared chitosan solution and immersing the coated samples in seawater at controlled environmental conditions for two weeks. Biofilms scraped from immersed chitosan coated panels showed no bacteria after 1 week of immersion. After the second week of immersion, less than 1500 bacteria/mm2 were observed on the chitosan-coated panels compared to more than 105 bacteria/mm2 on uncoated ones. Thus, this study proved the efficiency of chitosan coatings against micro- and macro-fouling.
