Marine lipids are used as ingredients in the nutraceutical, cosmetics and animal feed industries and can have different origins: biological (fisheries, micro-algae, genetically modified plants, synthetic) and from different geographical origins. The allegation associated with these ingredients (biosourcing, respect for the environment, sustainability, health benefits, dietary preferences, etc.) will lead to major differences in their price on a fast-growing market. This price disparity can lead to adulteration and fraudulent behaviors. Widespread standard analytical techniques (GC-FID, EA-IRMS) enable an initial characterization of the origin of crude oils. However, the refining and distillation processes used to produce concentrated compounds from crude oils can mask all or part of their biological or geographical origin. This calls for the development and implementation of more advanced and innovative methods to authenticate and trace lipid molecules, using hydrogen and carbon isotope analysis of specific compounds (CSIA). For companies from the above-mentioned sectors, beyond the legal and regulatory implications, the traceability of their ingredients is a major challenge in order to be able to guarantee compliance with their commercial policies and respect their commitments to the rational use of natural resources, and finally to preserve the value of the company's brand. It is therefore essential to identify the origin of lipids in suppliers' and commercial products, in order to detect and protect against fraud and adulteration. To meet these complex socio-economic, safety, regulatory and environmental challenges, the TrackinOil LabCom aims to bring together POLARIS and LEMAR's LIPIDOCEAN platform, internationally recognized respectively for their technical excellence in lipochemistry and polyunsaturated fatty acid processing, and for their scientific excellence in the accurate analysis of marine lipids. The aim of the LabCom will be to develop and commercialize innovative molecular profiling and compound specific isotopic signature tools for lipid ingredients used in the nutraceutical, cosmetics and animal nutrition sectors, by combining various chromatographic and spectrometric techniques (GC-FID/MS, GC-c/p-IRMS, EA-IRMS). The development of these tools will be structured along three main axes corresponding to decreasing degrees of operational maturity: i) optimizing and validating the traceability of long-chain n-3 polyunsaturated fatty acids (TRL 5-6), ii) developing the traceability of isoprenoids (phytosterols, squalene, tocopherols) (TRL 3-4), iii) and carotenoids (TRL 1-2). In addition to the techniques already mastered by the joint laboratory, the potential analytical contribution of NMR, LC-MS²-HRMS and LC-IRMS will also be explored. In parallel with the development of traceability tools, it will be essential to implement a library of reference lipids, and to maintain a market and scientific watch on emerging lipid ingredients and their sourcing. Finally, the LabCom will implement quality assurance procedures to meet international standards, in line with the ongoing validation of technical innovations for lipid traceability. Ultimately, the joint laboratory will be able to offer TM-type certification of lipid ingredients by molecular profiling and compound specific isotopic signature, so that traceability can be marketed as a high value-added service.

BIIM aims to 1) assess the processes leading to the net dissolution of abiotic particulate iron from sedimentary and hydrothermal origin, and 2) evaluate its impact on marine biogeochemistry. This is a crucial topic, as dissolved iron controls marine biological productivity and carbon sequestration in over 30% of the global ocean. Abiotic particulate iron has been up to now considered as refractory material. Recent observations question this assumption and suggest that this iron pool may be prone to dissolution. However, the exchange mechanisms between the particulate and dissolved pools of iron have only been superficially identified and quantified. Laboratory experiments will be inspired from the modellers’ needs and will assess the dissolution rates of particles from different compositions and origins as a function of environmental factors such as temperature, light levels, or concentrations of organic ligands. These controlling factors are needed by the modellers in the perspective of a global modeling of abiotic particulate iron. The key processes identified during the laboratory experiments will then be modelled using simple 0D models, based on mathematical relationships inferred during these experiments. The parameters values will be obtained by approaching the best possible fit between the model results and the outcome of the laboratory experiments. Finally, abiotic particulate iron cycle, derived from the 0D models, will be added to the three-dimensional global ocean model NEMO-PISCES which, for now, only considers sedimentary and hydrothermal dissolved iron source. This 3D model exercise will allow assessing the potential impact of the abiotic particulate iron on the biogeochemical cycles and in particular, but not restricted to, the carbon cycle. This project relies on a strong collaborative effort between modelers and observationalists. BIIM will also allow the PI, hired at CNRS in 2014, to further develop her research and to gather a community on the emerging and pivotal topic of particulate trace metals.

During the geological history of the Earth, evolutionary competition for dissolved silicon in the ocean directly influenced changes in the global cycles of silicon, carbon, and other nutrients that regulate ocean productivity and ultimately the Earth’s climate. Radiolarians are key players of this evolution and, as such, have provided rich palaeontological records for a multitude of palaeoceanographic studies. These marine micro-organisms, which can produce intricate skeletons of silica, are very sensitive to changes in environmental conditions. The resistant silica-based skeletons of radiolarians are particularly useful in regions of importance for studying climate change where carbonate-based archives are poorly preserved (e.g. Southern Ocean) and offer a biogeochemical window into the mid-depth section (i.e. 30-500 m) of the marine environment. The mid-depth zone in the marine environment is currently inaccessible for Si cycle palaeo-reconstructions and its characterization is pivotal to the detection of glacial–interglacial changes in water column stratification, which plays a critical role during periods of abrupt climate change. Fortunately, radiolarians are common plankton found in this mid-depth zone. However, in contrast to other silicifying organisms found in the palaeo-record, such as deep-water sponges and surface dwelling diatoms (unicellular silicifying micro-algae), the use of radiolarian geochemistry to describe palaeoceanographic variation in dissolved Si (DSi) is very much in its infancy largely due to the challenges associated with their growth under laboratory-controlled conditions and limited knowledge on the factors that govern their contemporary biogeographic distribution. The RadiCal project offers to develop Radiolarians as a novel palaeo-proxy for marine silicon cycling by Calibrating the silicon stable isotope composition (d30Si) of these organisms to their modern environment. This objective will be achieved by applying an innovative multidisciplinary approach evaluating the influence of the modern environment and taxonomy on the variability of radiolarian silicon isotope fractionation (1) in situ, (2) under laboratory-controlled conditions, and (3) from a core-top calibration study from a variety of different oceanographic basins within the Southern Ocean. RadiCal fosters the innovative and inter-disciplinary approach of the P.I., which aims to combine non-traditional stable isotope biogeochemistry with in situ observations, in vitro experimental culture experiments, and sediment core samples in order to answer questions regarding the role of marine silicifiers (e.g. radiolarians) on the global cycling of Si. The RadiCal project will also develop collaborations between French and foreign scientists, strengthen the link between internationally recognized laboratories, and aggregate a community of researchers with diverse expertise on silicifying organisms (e.g. radiolarians) while developing potential for further collaboration and development of larger scale projects (e.g. ERC). In addition, the project RadiCal will permit the training of a new generation of oceanographers using an innovative and multi-disciplinary approach.

The ECO-SmartAF project aims to develop new sustainable and environmentally friendly marine antifouling coatings to reduce the carbon footprint of maritime transport. Our approach is to design smart coatings that combine contact activity with appropriate amphiphilic surface chemistry, both of which prevent the adhesion of marine organisms. Smart alkoxyamine-based monomers will be designed to prepare seawater and/or enzyme-responsive polymers to generate nitroxyl and alkyl radicals, active towards the targeted marine organisms. The well-known rapid degradation (a few microseconds) of the alkyl radical will prevent its bioaccumulation and its prolonged contact with marine species that could become resistant. New methacrylic graft copolymers composed of hydrophobic poly(dimethylsiloxane) and hydrophilic poly(ethylene glycol) side segments will be synthesized to impart an amphiphilic character to the coating surface. Seawater hydrolyzable trialkylsilyl ester-based (meth)acrylic monomers will be inserted to promote changes in surface properties with immersion. The chemical composition of copolymers will be tuned to promote the presence of alkoxyamine-based units at the coating surface. Copolymers will be used (i) as matrix in erodible coatings and (ii) as additive in silicone elastomer-based fouling release coatings. Effectiveness of newly developed coatings will be assessed both through laboratory and field assays, including different model species and environmentally dissimilar coastal immersion sites. A wide range of toxicity tests will be carried out on bacteria, artemia and microalgae to ensure that the new coatings are environmentally friendly. An ecotoxicological risk analysis will be performed on leachates using a recently developed marine cell culture model of oyster Crassostrea gigas immune cells.

Primary producers form the basis of marine food webs, control population sizes at higher trophic levels and fish stock recruitment. Marine photoautotrophic organisms are also responsible for nearly half of the global net primary production, i.e., they replenish the ocean (and atmosphere) with oxygen and fix substantial amounts of carbon. Despite its outstanding relevance for the functioning of marine ecosystems and global climate, past primary production dynamics and mechanisms controlling them are not well characterized. This is particularly true for nearshore coastal environments and for times prior to significant human perturbation of biogeochemical cycles. Available data sources for changes in marine primary production (i) do not provide the necessary temporal resolution to resolve short-lived and spatially restricted phytoplankton blooms, specifically in shallow waters, (ii) are too short to distinguish trends from low-frequency cycles of primary production and (iii) do not cover the entirety of photoautotroph taxa which include more than just phytoplankton and cyanobacteria, i.e. microphytobenthos and macroalgae. Therefore, this project will develop an innovative technique that can provide reliable, temporally well-constrained, seasonally to inter-annually resolved data on past primary production dynamics in coastal nearshore environments based on shells of bivalve mollusks. For this purpose, we will test and refine existing proxies (surrogates) for primary production, and develop new proxies and integrate them in a multiproxy approach. In order to obtain a mechanistic understanding of how information on the species composition and number of marine photoautotrophs is recorded in chemical properties (Ba/Ca, Mo/Ca, Li/Ca, stable isotopes of carbon and nitrogen, triple isotope composition of oxygen, pigments) and color (hue and saturation index) of the shells, field and tank experiments will be conducted during which environmental variables can be closely monitored and manipulated. Since the study involves experiments with living bivalves we chose the fast-growing species, Pecten maximus, and an ecosystem that has been studied in great detail, the Bay of Brest, France. The multiproxy approach will subsequently by applied to subfossil shells collected from an archaeological site to determine the human impact on primary production dynamics of the Bay of Brest including (i) the seasonal occurrence of photoautotrophs as well as the intensity, frequency and seasonal timing of phytoplankton blooms, (ii) shifts in species composition and biomass through time and (iii) changes in the link between organisms inhabiting the sea floor and those living near sea surface. Results of this study will significantly advance marine sciences including paleoecology, paleoclimatology and fisheries sciences.