Claire Hellio

Université de Bretagne Occidentale | UBO · Laboratoire des Sciences de l’Environnement Marin- LEMAR (UMR 6539)

In the current study we investigate the antifouling potential of three polyphenolic resveratrol multimers (-)-hopeaphenol, vaticanol B and vatalbinoside A, isolated from two species of Anisoptera found in the Papua New Guinean rainforest. The compounds were evaluated against the growth and settlement of eight marine microfoulers and against the set...

The aims of this study are to stop biofouling formation and to create antibacterial layers on aquaculture nets using a chemical product known for its antibacterial behavior. Polyamide 6.6 and high-density polyethylene nets were grafted with polyethylene glycol by following two methods. At first, grafted nets were evaluated with SEM and XPS in order...

Marine biofouling seriously affects the field of aquaculture. On the one hand, it causes structural fatigue of nets and on the other hand, it has harmful consequences on the health of farmed species. The aims of this study were to develop antibacterial nets using methacrylic acid and dyes. At first, polyamide 6.6 nets were grafted with methacrylic...

Marine biofouling seriously affects the field of aquaculture. On the one hand, it causes structural fatigue of nets and on the other hand, it has harmful consequences on the health of farmed species. The aims of this study were to develop antibacterial nets using methacrylic acid and dyes. At first, polyamide 6.6 nets were grafted with methacrylic...

In marine environments, biofilm can cause negative impacts, including the biofouling process. In the search for new non-toxic formulations that inhibit biofilm, biosurfactants (BS) produced by the genus Bacillus have demonstrated considerable potential. To elucidate the changes that BS from B. niabensis promote in growth inhibition and biofilm form...

Understanding and sensing microbial biofilm formation onto surfaces remains highly challenging for preventing corrosion and biofouling processes. For that purpose, we have thoroughly investigated biofilm formation onto glassy carbon electrode surfaces by using electrochemical technics. Pseudomonas aeruginosa was studied because of its remarkable ab...

Biofilms, responsible for many serious drawbacks in the medical and marine environment, can grow on abiotic and biotic surfaces. Commercial anti-biofilm solutions, based on the use of biocides, are available but their use increases the risk of antibiotic resistance and environmental pollution in marine industries. There is an urgent need to work on...

Marine animal by-products of the food industry are a great source of valuable biomolecules. Skins and bones are rich in collagen, a protein with various applications in food, cosmetic, healthcare, and medical industries in its native form or partially hydrolyzed (gelatin). Salmon gelatin is a candidate of interest due to its high biomass production...

Many antifouling coatings had been proposed to limit the marine biofouling phenomenon, but they were found to be toxic on aquatic species. In this study, attempts are being made to develop fouling resistant nets by dyeing with reactive dye that contains copper in its composition. Stabilized copper in the dye molecule may be useful since it is well...

In aquaculture field, the adhesion of aquatic organisms on nets leads to the restriction of the oxygen supply and nutrient exchange and so the health of farmed species gets affected. In this study, our aims are to create antibacterial layers on nets using polyethylene glycol which is known for its antibacterial behavior. Polyamide 6.6 and high-den...

Bacterial biofilms have a significant economic and health impact in many different domains. In such films, the extracellular matrix prevents the diffusion of biocides, so antibiotic treatments require a concentration 500 to 1000 times higher than that used to eliminate the same bacteria when present as planktonic stage. Early detection of biofilms...

Phaeodactylum tricornutum (Bacillariophyta) is a worldwide-distributed diatom with the ability to adapt and survive in different environmental habitats and nutrient-limited conditions. In this research, we investigated the growth performance, the total lipids productivity, the major categories of fatty acids, and the antioxidant content in P. trico...

Nowadays, biofouling is responsible for enormous economic losses in the maritime sector, and its treatment with conventional antifouling paints is causing significant problems to the environment. Biomimetism and green chemistry approaches are very promising research strategies for the discovery of new antifouling compounds. This study focused on th...

The search for effective yet environmentally friendly strategies to prevent marine biofouling is hampered by the large taxonomic diversity amongst fouling organisms and a lack of well-defined conserved molecular targets. The acetylcholinesterase enzyme catalyses the breakdown of the neurotransmitter acetylcholine, and several natural antifouling al...

Marine biofouling plagues all maritime industries at vast economic and environmental cost. Previous and most current methods to control biofouling have employed highly persistent toxins and heavy metals, including tin, copper, and zinc. These toxic methods are resulting in unacceptable environmental harm and are coming under immense regulatory pres...

The marine environment is a generous source of biologically active compounds useful for human health. In 50 years, about 25,000 bioactive marine compounds have been identified, with an increase of 5% per year. Peculiar feature of algae and plants is the production of secondary metabolites, such as polyphenols, synthesized as a form of adaptation to...

Seagrass beds are increasingly impacted by human activities in coastal areas, particularly in tropical regions. The objective of this research program was to study seagrass beds characteristics under various environmental conditions in the French Antilles (FA, Caribbean Sea). A total of 61 parameters, from plant physiology to seagrass ecosystem, we...

Chemical investigation of the South-Pacific marine sponge Suberea clavata led to the isola- tion of eight new bromotyrosine metabolites named subereins 1–8 (2–9) along with twelve known co-isolated congeners. The detailed configuration determination of the first representative major compound of this family 11-epi-fistularin-3 (11R,17S) (1) is descr...

The settlement and growth of fouling organisms on man-made surfaces can be prevented by the application of antifouling paints containing active compounds (biocides, heavy metals), most of which are toxic to non-target organisms. As part of our research program in chemical ecology and blue biotechnology, we are conducting studies to investigate the...

Stationary and slow-moving marine organisms regularly employ a natural product chemical defense to prevent being colonized by marine micro- and macroorganisms. While these natural antifoulants can be structurally diverse, they often display highly conserved chemistries and physicochemical properties, suggesting a natural marine antifouling pharmaco...

Treatment of skin wounds is an important domain in biomedical research since many pathogenic bacteria can invade the damaged tissues causing serious infections. Effective treatments are required under such conditions to inhibit microbial growth. Plants are traditionally used for the treatment of skin infections due to their antimicrobial potential....

Biofouling causes major problems and economic losses to marine and shipping industries. In the search for new antifouling agents, marine bacteria with biosurfactants production capability can be an excellent option, due to the amphipathic surface-active characteristic that confers antimicrobial and antibiofilm activities. The aim of this study was...

The protection of steel against marine biofouling is usually achieved by the application of protective coatings. In this work, an antifouling coating based on alginate biopolymer was developed using the electrophoretic deposition method. Zinc cations have been incorporated into the material to obtain some anti-algae / bacteria properties and calciu...

Four new brominated tyrosine metabolites, aplyzanzines C-F (1-4), were isolated from the French Polynesian sponge Pseudoceratina n. sp., along with the two known 2-aminoimidazolic derivatives, purealidin A (5) and 6, previously isolated, respectively, from the sponges Psammaplysilla purpurea and Verongula sp. Their structures were assigned based on...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Unraveling new environmentally friendly antifouling (AF) agents is one of the major quests currently facing marine biotechnology. Marine macroalgae represent a rich source of new compounds with promising biological properties, including AF activity, but most of the macroalgal compounds studied to date are terpenoids or polyphenolics. The aim of thi...

Microalgae represent a new source of biomass for many applications. The advantage of microalgae over higher plants is their high productivities. The photoautotrophic microalgae include all photosynthetic microorganisms, i.e. Cya-nobacteria (prokaryotes) or microalgae (eukaryotes). These microorganisms are characterized by a large biodiversity and c...

The need for new environmentally friendly antifouling and the observation that many marine organisms have developed strategies to keep their surface free of epibionts has stimulated the search for marine natural compounds with antifouling activities. Sponges and in particular fungi associated with them represent one of the most appropriate sources...

The effect of biofilm formation on passive stainless steel in seawater environments is of primary importance since it leads to potential ennoblement of surfaces and subsequently to localized corrosion such as pitting and crevice corrosion. This study aims at developing an ecofriendly alginate biopolymer containing both non-toxic calcium and a limit...

In this study we focused on four taxa of the genus Calendula (C. maritima, C. suffruticosa subsp. fulgida, C. arvensis, and the hybrid between the first two ones), collected in Mediterranean area (Sicily). Six extracts for each species were obtained using solvents with increasing polarity (hexane, ethanol 80%, acetone 70%, and water) and through ex...

Biofouling causes major economic losses in the maritime industry. In our site study, the Bay of La Paz (Gulf of California), biofouling on immersed structures is a major problem and is treated mostly with copper-based antifouling paints. Due to the known environmental effect of such treatments, the search for environmentally friendly alternatives i...

Mayotte Island is located in Comoros archipelago and shelters multispecific meadow where nine seagrass species inhabit and which are frequented by their grazers the green turtle (Chelonia mydas) and more rarely by the dugong (Dugong dugon). With the increase of demography and coastal activities, the conservation of this threatened lagoon habitat an...

Climate change (CC) is driving modification of the chemical and physical properties of estuaries and oceans with profound consequences for species and ecosystems. Numerous studies investigate CC effects from species to ecosystem levels, but little is known of the impacts on biofilm communities and on bioactive molecules such as cues, adhesives and...

Climate change (CC) is driving modification in the chemical and physical properties of estuaries and oceans with profound consequences for species and ecosystems. Numerous studies investigate CC effects from species to ecosystem levels, however little is known of impacts on biofilm communities and bioactive molecules, like cues, glues, and enzymes....

Article en page 8 de la newsletter. La mutualisation des actions nationales « herbiers » de l’Ifrecor et de la DCE a conduit au lancement d’une phase de recherche et développement afin de développer des protocoles et des indicateurs sur les herbiers répondant aux objectifs de ces deux programmes. C’est dans ce cadre que la thèse intitulée « Dévelo...

Article en page 24 de la newsletter. La mutualisation des actions de l'Ifrecor et de la DCE a conduit au lancement d’une phase de recherche et développement afin de développer des protocoles et des indicateurs « herbiers ». C’est dans ce cadre que la thèse intitulée « Développement d’outils méthodologiques pour le suivi et l’évaluation de l’état d...

Chemical study of the CH 2 Cl 2-MeOH (1:1) extract of the sponge Fascaplysinopsis reticulata collected in Mayotte highlighted three new tryptophan derived alkaloids, 6,6-bis-(debromo)-gelliusine F (1), 6-bromo-8,1-dihydro-isoplysin A (2) and 5,6-dibromo-8,1-dihydro-isoplysin A (3), along with the synthetically known 8-oxo-tryptamine (4) and the thr...

Regulatory developments regarding antifouling molecules encourage the search for non-toxic substances. Evaluation tools must evolve to highlight anti-adhesion effects rather than growth inhibition. The work presented here aimed at developing a method based on confocal laser scanning microscopy-microfluidic flow-cells in order to characterize microa...

This study aimed at the characterization of the antioxidant power of polyphenol extracts (PE) obtained from the algae Cystoseira foeniculacea (CYS) (Phaeophyta) and from the halophyte Halocnemum strobilaceum (HAL), growing in the solar saltworks of western Sicily (Italy), and at the evaluation of their anti-microfouling properties, in order to corr...

Following their planktonic phase, the larvae of benthic marine organisms must locate a suitable habitat to settle and metamorphose. For oysters, larval adhesion occurs at the pediveliger stage with the secretion of a proteinaceous bioadhesive produced by the foot, a specialized and ephemeral organ. Oyster bioadhesive is highly resistant to proteomi...

Post-harvesting, handling and storage practices, particularly during the summer months, are crucial for mussel farms, as they induce stress, mortalities and affect overall performance and marketability. In the current work, Mediterranean farmed mussels, were stored into plastic net bags of different weights (7.5kg, 10 kg, 12.5 kg and 15 kg) and re-...

Microorganisms have the ability to settle on nearly all man-made surfaces in contact with seawater and subsequently to form biofilm. Biofilms control and removal is necessary in the sectors of maritime transport, energy... In this work, we present the development of new pure calcium, zinc or copper alginate, but also mixed Ca/Cu and Ca/Zn alginate...

Bioadhesion of marine organisms has been intensively studied over the last decade because of their ability to attach in various wet environmental conditions and the potential this offers for biotechnology applications. Many marine mollusc species are characterized by a two-phase life history: pelagic larvae settle prior to metamorphosis to a benthi...

One way of reducing the input of pollutants into the marine environment is to enforce the use of non-toxic antifouling paints in marine protected areas. Thus, the purpose of this study was to detect marine microorganisms that secrete inhibitory substances against bacteria and microalgae to avoid biofouling on man-made structures in La Paz bay, B.C....

Marine sponges are recognized as a rich source of new marine natural products. In this study, chemical investigation of the CH 2 Cl 2-MeOH (1:1) extract from the marine sponge Haliclona fascigera collected in Mayotte was carried out and highlighted a new unusual acetylenic and tetrahydrofuranic fatty acid, (2S*,5S*,6Z)-2,5-epoxydocosan-6-en-21-ynoi...

By combining the recently reported repelling natural dihydrostilbene scaffold with an oxime moiety found in many marine antifoulants, a library of nine antifouling hybrid compounds was developed and biologically evaluated. The prepared compounds were shown to display a low antifouling effect against marine bacteria but a high potency against the at...

First bastadins isolated from the marine sponge Ianthella basta have attracted wide attentions due to their biological activities. Bastadins are known for their antifouling, antimicrobial and anti-inflammatory properties. From these naturals compounds, chemists from the university of Düsseldorf have developed many bastadins or hemibastadins analogs...

Dibromohemibastadin-1 (DBHB) is an already known potent inhibitor of blue mussel phenoloxidase (which is a key enzyme involved in bioadhesion). Within this study, the potentiality of DBHB against microfouling has been investigated. The activity of DBHB was evaluated on key strains of bacteria and microalgae involved in marine biofilm formation and...

Since the banning of several families of compounds in antifouling (AF) coatings, the search for environmentally friendly AF compounds has intensified. Natural sources of AF compounds have been identified in marine organisms and can be used to create analogues in laboratory. In a previous study, we identified that dibromohemibastadin-1 (DBHB) is a p...

A total of 346 live animals of the endangered species fan mussel Pinna nobilis (Linnaeus 1758) were recorded in situ in the shallow water zone (<2m) within two sites of the marine protected area " Natura 2000 " of Maliakos Gulf (Central Hellas). Our results showed that the recorded length (from 11.89 to 72.51 cm) of the fan mussels corresponds to a...

The current study reports the first comprehensive evaluation of a class of allelopathic terrestrial natural products as antifoulants in a marine setting. To investigate the antifouling potential of the natural dihydrostilbene scaffold, a library of 22 synthetic dihydrostilbenes with varying substitution patterns, many of which occur naturally in te...

The environment is the inspiration for many innovations, for example in the research on new antifouling surfaces; the shark skin is an interesting model. On the shark skin, it was shown that microtopography associated with production of mucus inhibited microfouling and macrofouling. In our study, we want to evaluate the property of the surface roug...

Algae have the ability to produce a huge variety of chemical defenses,among them some prevent over-predation, competition from colonizing microorganisms or help reduced the oxidative stress. These molecules are a source of natural compounds with high interest for therapeutic and cosmetic applications. Our research project focused on highlighting th...

Among microorganisms involved in the microfouling, microalgae are present in great number and diversity but few studies investigate their ability to adhere on a support and to create communities like bacterial biofilms. In this study, parameters promoting the formation of microalgae biofilm in flowcell system1 were determined. Two strains of microa...

First adhesion stages of oyster Crassostera gigas larvae are very poorly documented. Oyster larvae start their life by a two-weeks swimming phase, leading to the pediveliger stage which is characterized by the apparition of the foot, a specific organ which is essential for adhesion. Pediveliger larvae stop swimming, fall to the bottom and explore t...

The current study represents the first comprehensive investigation into the general antifouling activities of the natural drimane sesquiterpene polygodial. Previous studies have highlighted a high antifouling effect toward macrofoulers, such as ascidians, tubeworms, and mussels, but no reports about the general antifouling effect of polygodial have...

Since 2011, the Lesser Antilles have faced major events of the washing ashore of pelagic Sargassum. Windward, exposed island coasts receive tons of algae that alter the quality of coastal ecosystems and the environment. The events repeated in 2012, 2014, 2015 and 2016. A major concern for local governments is to predict arriving floating algae and...

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