Aim: to set up a trans-channel centre for the elaboration of green intelligent “smart” biomaterials



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  • Aim: to set up a trans-channel centre for the elaboration of green intelligent “smart” biomaterials

  • Duration : October 2010 – 2013



  • University of Rouen Polymeres, Biopolymeres, Surfaces laboratory (PBS) ,

  • Dr L. Lebrun



  • to prevent the growth of micro-organisms by using natural biocides or anti-biofilm molecules (polysaccharides and peptides produced by algae)

  • to screen new molecules able to inhibit biofilm formation

  • to share knowledge and complementary expertise of the partners to develop new support modification technologies







In order to prevent colonization, many algae have developed chemical defences

  • In order to prevent colonization, many algae have developed chemical defences

  • Wide variety of chemically active metabolites

  • variety of activities ( anti-bacterial, anti-inflammatory ….)

  • Sustainable resources



  • Biodiversity

  • Availability of the biomass

  • Known to be unfouled



Green tide in Europe are becoming more frequent

  • Green tide in Europe are becoming more frequent

  • More than 100 000 m3 of Ulva sp. collected in North Brittany in 2011

  • Extract from Ulva sp : inhibitory effects on dinoflagellates (Jeong et al. 2000) and development of invertebrates (Johnson and welsh, 1985)

  • Ulvans are structural acid polysaccharides present in cell wall of Ulva sp. , they represent 8-29% of the dry weight



Ulva clathrata

  • Ulva clathrata



Invasive species : chemical defense strategy

  • Invasive species : chemical defense strategy

  • Undaria sp. and Sargassum sp.

  • Fucoidan Polyphenol







96 wells-microplates

  • 96 wells-microplates

  • 4 concentrations : 0.01, 0.1,1 and 10 µg/ml

  • 6 replicates

  • Solvent evaporation

  • Sterilization under UV

  • 8 strains of bacteria :

  • 100µl / well, incubation 48h at 24°C, measurement of OD620 nm and determination of Minimum Inhibition Concentration (MIC) (µg/ml)



  • 3 strains of microphytobenthic microalgae

  • Media F/2 (Guillard et al. 1962)

  • Constant light 140 µmol m-2 s-1

  • T° 20° C



Chlorophyll a extraction :

  • Chlorophyll a extraction :

  • Filtration of 10 ml of microalgae suspension

  • Addition of methanol and extraction at 4°C in the dark

  • Fluorescence measurement : excitation 485 nm – emission 645 nm

  • Bioassay :

  • 100 µL microalgal suspension (0.1 mg[Chl a] L-1)

  • 4 concentrations : 0.01, 0.1, 1, 10 µg/ml

  • 6 replicates

  • 5 days incubation : 20 °C, constant light 140 µmol m-2 s-1

  • Chlorophyll a extraction and measurement of fluorescence : excitation 485nm - emission 645 nm

  • Determination of MIC ( µg/ml)





  • All strains are inhibited by at least one product

  • U3 show inhibition activity at low concentration against 3 of the vibrio strains

  • Inhibition against v.aesturianus , a known pathogen for oyster : possible application in aquaculture

  • 4 ulvans and 1 fucoidan inhibit V.harveyi, responsible for a disease that affects commercially farmed penaid prawns : possible application in aquaculture



  • inhibition at low concentration against Pseudoalteromonas elyakovii

  • U1-6 show growth inhibition activity against 4 of the strain tested

  • Differents activities for ulvans extracted from U.armoricana





7 compounds show inhibition activies at low concentration against marine bacteria and microalgae

  • 7 compounds show inhibition activies at low concentration against marine bacteria and microalgae

  • Ulvans from U.compressa looks particularly promising







  • Immobilisation of the most promising compounds on TiO2

  • Inclusion of the most promising compound in hydrogel

  • Field assays



  • University of Rouen Polymeres, Biopolymeres, Surfaces laboratory (PBS) ,

  • Dr L. Lebrun





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