Natural product antifoulants: One perspective on the challenges related to coatings development

Abstract

Fouling of surfaces by abiotic and biotic substances has molecular, microbial, and macro-organismal levels of organization. Fouling involves molecular bonding and biological adhesives. Existing commercial solutions to fouling are antifouling or foul-release. Antifouling uses broad-spectrum biocides which kill foulers by virtue of oxidation or toxic metal ions. Foul-release coatings are dimethyl silicone polymers that foul, but clean easily. The best foul-release coatings also contain additives that kill organisms. Environmentally unacceptable consequences of toxic antifouling coatings, especially those based on organotins, have prompted interest in antifoulants found in living organisms. Laboratories worldwide now use bioassays with target fouling organisms to direct purification and identification of antifoulant compounds. Natural antifoulants are common and include toxins, anesthetics, surface-active agents, attachment and/or metamorphosis inhibitors and repellents. Development of commercial coatings using natural products is blocked by cost, the time horizon to meet government regulations and performance standards based upon coatings with unacceptable environmental impacts. If blocks are removed, the potential for environmentally acceptable solutions that combine natural products with organic biocides is high.

Evaluation of the Activity of the Sponge Metabolites Avarol and Avarone and their Synthetic Derivatives Against Fouling Micro- and Macroorganisms

“…One of the most serious problems that marine technology is currently facing is the control of biofouling on man-made structures [1,2]. Efficient antifouling paints are based on copper compounds and booster biocides that when submerged, release toxic compounds causing adverse environmental effects [3][4][5][6][7][8].…”

Satellite tag attachment methods for tracking neonate sea turtles

“…Some organisms with base plates, such as barnacles, survived. The calcareous base of barnacles protects their soft tissues from the toxic coating (Rittschof 2000). While a more diverse group of organisms was attracted to T2-treated solar cells, soft fouling organisms died when in contact with T2 and thus did not have long-term fouling effects.…”

Anti-Biofouling Defence Mechanism of Basibionts (A Chemical Warfare) - A Critical Review

“…These compounds can act enzymatically by dissolving the adhesives, interfering with the metabolism of the fouling organisms (e.g., nervous pathway interference), inhibiting the attachment, metamorphosis or growth, promoting negative chemotaxis, altering the surface of the organisms and as repellents [39][40][41]. Octocorals (class Anthozoa, subclass Octocorallia, and order Alcyonacea, family Alcyoniidae) were one of the first benthic invertebrate groups that were systematically screened for secondary metabolites (Tursch, 1976).…”