Joint-action of antifouling substances in copper-free paints.

International audienceDue to the environmentally harmful impact of tributyltin self-polishing paints, there is a critical need of more ecological alternatives. The aim of the present work is to study the joint-action of three molecules chosen in order to combine the two modes of prevention: chemical and physical repelling of biofouling. This "hybrid" system is principally dedicated to disturb durable settlement of microfouling. Each component was chosen according to its specific properties: chlorhexidine is a bisdiguanide antiseptic with antibacterial activity, zinc peroxide is an inorganic precursor of high instable entities which react with seawater to create hydrogen peroxide, Tween 85 is a non ionic surfactant disturbing interactions between colonizing organisms and surface. Obtained results highlighted the interest on mixing such molecules to get additive action on antifouling efficiency

Development of environmentally friendly antifouling paints using biodegradable polymer and lower toxic substances

The development of new antifouling coatings with respect to the marine environment is actually crucial. The aim of the present work is to concept an erodible paint formulated with biodegradable polyester as binders and which combines two modes of prevention: chemical and physical repelling of biofouling. This system is principally dedicated to disturb durable settlement of microfouling. Each component was chosen according to its specific properties: chlorhexidine is a bisdiguanide antiseptic with antibacterial activity, zinc peroxide is an inorganic precursor of high instable entities which react with seawater to create hydrogen peroxide, Tween 85 is a non ionic surfactant disturbing interactions between colonizing organisms and surface. Obtained results highlighted the interest on mixing such molecules to obtain a promising coating with lower toxicity than traditional systems

Tropical microalgae isolated on Reunion island (France, Indian Ocean) as sources of antifouling molecules: The BIOPAINTROP project

International audienceBiofouling is associated to colonization of artificial submerged structures by aquatic organisms. This process induces adverse effects such as loss of hydrodynamism, corrosion, weight increase of equipments. Numerous toxic compounds (copper, arsenic) have been used during decades to avoid biofouling of ships, until EU has banned them since 2008. For this reason, a new strategy, focusing on environmental friendly molecules is requested aiming to provide coatings that progressively release active natural compounds, non-toxic for environment. As a significant component of marine organisms, microalgae are a promising source of active natural substances, with biotechnological potential value. Growing microalgae is a worldwide project for various purposes actually e.g. biofuel. BIOPAINTROP project aims to develop antifouling coatings with active biomolecules originating from tropical marine resources (microalgae) from Reunion Island. Two main objectives have been designated: (i) identification of active molecules fromtropical microalgae and (ii) incorporation of these compounds in adequate coatings and confirmation of the efficiency of these products in both temperate and tropical marine environments. To reach the targeted results, a pluridisciplinary group has been set up with 6 French teams with complementary expertises: (i) HYDRÔ based on Reunion island and specialized in tropical marine microalgae, (ii) three University laboratories: LCSNSA (Reunion) specialized in natural products valorisation; LBCM (Bretagne) specialized in marine biotechnologies; MAPIEM (Toulon) specialized in polymer materials engineering and marine biocompounds, (iii) Private partners: NAUTIX producing environmental friendly paints, expert in processing ecological and antifouling coatings; BIOALGOSTRAL a start-up from Reunion specialized in production/valorisation of microalgae biomass