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International audience; Editorial on the Research Topic Microbial Biotechnology Providing Bio-based Components for the Food Industry This Frontiers Research Topic provides an inter-and multidisciplinary platform for reviews and researches dedicated to microbial biotechnology providing bio-based components for the food industry. The findings presented in this special issue give a foundation for enlarging the current exploitation of the metabolic diversity in fungi, yeasts, bacteria, and microalgae for improved production of food and other industrial products. Thus, this topic did appeal not just to those interested in the screening and metabolic investigation of microorganisms but also to the industrial biotechnology, the process optimization, the fermentation technology, and the bio-products research community. Ingredients derived from microbial fermentation or extracted from microalgae are steadily gaining ground in the food industries (Dufossé, 2018). Thickening or gelling agents (e.g., polysaccharides such as xanthan, curdlan, gellan), flavor enhancers (yeast hydrolysate, monosodium glutamate), lipids (polyunsaturated fatty acids-PUFAs, sterols), flavor compounds (gamma-decalactone, diacetyl, methyl-ketones), vitamins, essential amino acids, pigments/colorants (carotenoids, azaphilones) (Dufossé et al., 2014; Venil et al., 2014), surfactants and acidulants (lactic acid, citric acid) are some examples illustrating this trend of the bio-based economy. Efforts have been made and continue to be done in order to reduce the production costs of components produced by algal ponds and microbial fermentation, since synthetic ones or those extracted from natural plant sources can often be produced more economically. Fungi, yeasts, bacteria, and microalgae are considered as promising living organisms for sustainable, large-scale production of commodities such as food, feed, chemicals, materials, and biofuels. The special issue emphasizes the crucial role that microorganisms and microalgae are currently playing and are likely to continue to play in future as microbial cell factories for the production of food grade components and bio-based ingredients in general. This is due to the versatility in their metabolic pathways and biochemical profiles, amenability for easy large-scale cultivation, and a long history of production by well-investigated production strains. Topics broadly cover studies in Screening and selection, Molecular traits, Metabolic investigation and regulation, Analytical chemistry, Physiology and biochemistry, Process optimization, Fermentation, Extraction techniques, Biomass and bio-products, Cultivation technology, Formulation and applications. Joseph et al. have reviewed the current state and the perspectives of bioproduction of the recombinant sweet protein thaumatin, which is one of the most promising alternatives for sugar and artificial sweeteners. Recombinant DNA technology is used in the most favorable host known today, the methylotrophic yeast, Pichia pastoris.

International audience; Fungal naphthoquinones, like red bikaverin, are of interest due to their growing applications in designing pharmaceutical products. Though considerable work has been done on the elucidation of bikaverin biosynthesis pathway in Fusarium fujikuroi, very few reports are available regarding its bioproduction in F. oxysporum. We are hereby proposing a putative metabolic pathway for bikaverin bioproduction in a wild F. oxysporum strain by cross-linking the pigment profiles we obtained under two different fermentation conditions with literature. Naphthoquinone pigments were extracted with a pressurized liquid extraction method, and characterized by HPLC-DAD and UHPLC-HRMS. The results led to the conclusions that the F. oxysporum LCP531 strain was able to produce bikaverin and its various intermedi-ates, e.g., pre-bikaverin, oxo-pre-bikaverin, dinor-bikaverin, me-oxo-pre-bikaverin, and nor-bikaverin, in submerged cultures in various proportions. To our knowledge, this is the first report of the isolation of these five bikaverin inter-mediates from F. oxysporum cultures, providing us with steady clues for confirming a bikaverin metabolic pathway as well as some of its regulatory patterns in the F. oxysporum LCP531 strain, based on the previously reported model in F. fujikuroi. Interestingly, norbikaverin accumulated along with bikaverin in mycelial cells when the strain grew on simple carbon and nitrogen sources and additional cofactors. Along bikaverin production, we were able to describe the excretion of the toxin beauvericin as main extrolite exclusively in liquid medium containing complex nitrogen and carbon sources, as well as the isolation of ergosterol derivate in mycelial extracts, which have potential for pharmaceutical uses. Therefore, culture conditions were also concluded to trigger some specific biosynthetic route favoring various metabolites of interest. Such observation is of great significance for selective production of pigments and/or prevention of occurrence of others (aka mycotoxins).

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International audience; In the plant kingdom, numerous pigments have already been identified, but only a minority of them is allowed by legal regulations for textile dyeing, food coloring or cosmetic and pharmaceutics’ manufacturing. Anthraquinones, produced as secondary metabolites in plants, constitute a large structural variety of compounds among the quinone family. Derivatives that contain hydroxyl groups, namely hydroxy-anthraquinones, are colored. They have attracted the attention of many researchers due to their large spectrum of possible applications especially in the fields of dyeing. These dyes produce a wide range of nuances in shades (red, orange and yellow). Fifteen anthraquinones’ derivatives from madder color roots (Rubia tinctorium L.) play an important role in dyeing (CI Natural Red 8). Purpurin (CI Natural Red 16) is a minor component in the madder color, but is the main dye in addition with munjistin in Indian madder (Rubia cordifolia). Alizarin (Pigment Red 83, CI Mordant Red 11) is the main red dye in madder color. Several other species, although producing hydroxyanthraquinones dyes, are not considered viable contributors to the natural red dye market. This is the case of Anchusa tinctoria, Lithospermum spp., Carthamus tinctoria or Galium species. Some hydroxyanthraquinone dyes, either extracted from insects (carminic acid), microbes (Arpink red) or plants (alizarin from European madder roots), are already manufactured and marketed as natural colorants in textile, food, cosmetic or pharmaceutics industries. As these dyes are not yet widely applied, research work need to extend the knowledge concerning their potential roles on human health. Their positive and/or negative effects due to the 9,10-anthracenedione structure and its substituents are still not clearly understood and their potential role or effect on human health is currently being discussed by scientists. For example, rubiadin, lucidin, and more generally madder color, can induce carcinogenicity and should be dealt carefully as a significant carcinogen. In contrast, numerous pharmacological studies have proved that some hydroxyanthraquinones have positive effects. Examples including emodin, rhein, physcion, damnacanthal, purpurin, which can inhibit proliferation of various cancer cells. This work gives an overview on hydroxyanthraquinone dyes described in plants.

International audience; A new, easy and rapid synthesis of γ-dilactones is cis-fused with a cyclopentenic ring via cyclization of 7-chlorotriethylenic-malonic acids. The key step implicates an intramolecular cyclization to a cyclopentenyl cation, according to an electrocyclic π2s + π2a conrotatory process. This cyclopentenyl cation led to unstable γ-lactones intermediates that are rearrange to more stable isomers. δ-lactones (6Z and 6E-(3-chlorobut-2-en-2-yl)-5-methyl-3,6-dihydro-2H-pyran-2-one) were obtained as secondary products. Mechanistic pathways were considered. The structures of the newly synthesized compounds were established by elemental and spectral data.

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International audience; Filamentous fungi produce a mixture of various metabolites such as pigments, fatty acids, proteins and other cellular metabolites. Thus, extraction and isolation of the pigmented molecules of interest are necessary steps before proceeding to any further utilization of these metabolites for commercial applications. Pigments can be stored within the biomass, excreted in the fermentation broth or both, suggesting that extraction methods need to be developed accordingly to the cellular localisation of the pigments and to their chemical natures.Despite the wide range of separation techniques currently available, most of industrial extraction processes rely on conventional liquid-liquid systems using organic solvent (hexane, dichloromethane, toluene, THF, etc.). Since environmental pollution generated by chemical industries has become a central concern in societal and political decisions, there is a growing demand for the development of efficient and greener separation technologies. Over the last two decades, and with the emergence of the concept of green chemistry, tremendous progresses have been performed in extraction and separation technologies. Methods such as ultra-sound-assisted extraction, microwave-assisted extraction, pressurised fluid extraction, supercritical fluidextraction, enzyme-assisted extraction, and more recently, ionic liquid assisted extraction weredeveloped. The trend is to create extraction techniques involving cheap and environmental-friendlysolvents that can be used under milder conditions with good final efficiency in quicker processes(ideally automatized). From the newest systems, ionic liquids have been recognized as verypromising new extraction solvents due to the possibility to tailor their chemical properties andaffinities to the target biomolecules.The focus of this work is to present an overview of the potentialities of the main emergingextraction methods on fungal matrixes for pigments isolation and recovery, with a particularinterest for ionic liquids.Emerging greener extraction systems for fungal pigments isolation. Lebeau J.L.D., Venkatachalam M., Fouillaud M., Dufossé L., Caro Y.. Proceedings of the 8th International Congress of Pigments in Food – “Coloured foods for health benefits”, Cluj-Napoca, Romania, June 28 - July 01, 2016. Socaciu C. & Pintea A. (Eds.), University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Romania (Publ.), ISBN 978-606-8778-11-2, p 64, 2016.

ISBN 978-606-8778-11-2; International audience; Talaromyces albobiverticillius-is a pigment producing ascomycete fungi isolated from the marine biodiversity of Réunion Island, Indian Ocean, France. Due to the extensive interest in process development for pigment production from natural microbial sources among scientists and manufacturers, much attention has to be paid to unfold marine treasure to find some novel pigment producers. Media composition and growth conditions influence culture growth and thus have an effect on pigment production. The production of pigment(s) can be improved by optimizing the culture conditions. Traditional optimization techniques such as " One factor at a time " fail to identify the variables that give rise to maximum response, and also consume labor and time. Statistical methods are an alternate to traditional methods, a process by considering the mutual interactions among the variables to optimize responses. Response Surface Methodology (RSM) is one such technique which simplifies optimization study by considering mutual interactions in a statistically valid manner. A three level four factor Box Behnken Design (BBD) was used to identify the effect of process variables such as initial pH, temperature, agitation rate and incubation period on pigment production and biomass growth. From BBD results, the most optimal conditions for pigment production were found to be 24°C, 200rpm with initial pH of 6.5. The yield of pigment was measured in terms of OD values and then converted to amount of pigments in µg/l equivalent to the standards used. With these optimized conditions, further study will be carried out to observe the effects of different nutritional factors such as carbon, nitrogen sources, and trace elements on pigment production. Acknowledgements

Poster communication, 8th International Conference of Pigments in Food, “Coloured foods for health benefits”, Cluj-Napoca, Romania, June 28 - July 01, 2016.; International audience; Filamentous fungi have been widely recognized as promising sources of various types ofbiomolecules and are therefore highly investigated. The production of fungal pigments is oneintensively studied domain in order to respond to the growing demand for natural colorants assubstitutes to synthetic dyes used in food, cosmetics, pharmaceutical and textile industries. Suchinterest in the natural origins of the pigments is driving the search for new and greener extractionsystems. It is desired to develop extraction processes that would use less organic solvents andmilder conditions, allow higher and quicker extraction yields, as well as improved selectivity andbetter recovery. Over the last two decades, ionic liquids (ILs) have caught attention as novel greensolvents, and have already been applied in various separation systems (membranes separation,additives in mobile phase and surface-bonded stationary phases in chromatography) [1]. ILs aremolten salts that can display a vast variety of chemical properties based on the specific associationof a bulky and asymmetric organic cation with an organic or inorganic anion. The use of anaqueous two-phase systems (ATPS) based on ionic liquids allows to tailor the extraction system tothe pigmented molecule of interest, here fungal pigmented polyketides. In this study, several ATPSbased on quaternary ammonium ([N4444]Br-) and immidazolium ([C4Mim]Cl- and [C4Mim]Br-)ionic liquids were investigated for the efficient extraction and recovery of soluble polyketidespigments from the fermented broth of four fungal strains: Talaromyces albobiverticillius,Emericella purpurea, Penicillium marquandii, Trichoderma harzianum. These four families areknown to produce mainly polyketides pigments such as azaphilone and hydroxyanthraquinonepigments, which are the main targets in the field of fungal pigments research [2,3]. The extractionefficiency of red, orange and yellow hues was investigated with a particular focus on the solublered pigments extraction efficiency and recovery from the three different ATPS tested. The resultsshowed that extraction yields of extracellular pigments of all hues from all strains are greater than80%, with [N4444]Br- and [C4Mim]Cl- reaching between 90 and 100% extraction efficiencies.Moreover, these two IL-based ATPS tend to preferably isolate red pigments under alkalineconditions, which is in agreement with previous studies [4]. The second step of this study, whichfocused on the recovery of the different pigments from the ILs, remains under investigation as theaffinity of the IL for the pigmented molecules seems high and difficult to reverse.Nevertheless, the initial results of this study bring novel strategies for the selective extraction ofextracellular fungal pigments. As a next step, further investigation would be required indetermining the specific solubility of azaphilones and hydroxyanthraquinones-like molecules in thedifferent ILs.

International audience; In industries, authorized red pigments are mainly issued from plants (as lycopene from tomato orbetalains from beetroot), cochineal insects (carmine red) or from chemical synthesis. Their uses aremore and more questioned with regard to the culture constraints or health problems. New resourcesfor the production of natural red colorants are therefore under focus [1, 2]. Marine-derived fungiare at the forefront in the search of new compounds of interest that could be produced throughbiotechnology [3]. In the field of colors, the marine-derived microfungi are able to synthesize awide diversity of pigments/ hues, amongst which red anthraquinones are well represented. Some oftheir main advantages are they are considered as natural, and their productions are « upscalable » inan industrial point of view. This work highlights the anthraquinoid red pigments known, up to date,from marine-derived fungi. We summarize about thirty compounds produced from about 25 strainsthat have been discovered in the former years. Beside the widespread Aspergillus, Alternaria,Eurotium, Fusarium or Penicillium, some original genera as Halorosellinia, Nigrospora,Stemphylium or Xylaria were identified as red anthraquinoid molecules’s producers. Well knownsubstances such as austrocortinin, catenarin, erythroglaucin or bostrycin were characterized in thefungal productions, as well as several new compounds, never mentioned, up to now, from otherorganisms. They could interestingly be further studied as potential sources of red colors to beoperated in food, cosmetic or dyeing industries. Beside their coloring properties, these compoundssometimes exhibit diverse biological activities such as antimicrobial or anticancer effects, sparselymentioned in the literature. This aspect, when available, is also documented, in order to examinethe potential use of these compounds and to help broadening the horizon of colors with innovativenatural substances.References:[1] L. Dufossé, M. Fouillaud, Y. Caro, S.A.S. Mapari, N. Sutthiwong, Current Opinion inBiotechnology 26, (2014), 56-61.[2] Y. Caro, L. Anamale, M. Fouillaud, P. Laurent, T. Petit, L. Dufossé, Natural Products andBioprospecting 2, (2012), 174-193.[3] R. Montaser, H. Luesch, Future Medicinal Chemistry 3, (2011), 1475-1489.

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Biofouling 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 from tropical 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.

International audience; A new rapid synthesis of γ-lactones, cis fused with a cyclopentenic ring by thermal cyclization of 7-chloro-2-(methoxycarbonyl)-4-6-dimethylocta-7-phenyl (or methyl) (2E,4E,6E)-trienoic acids was reported. The key step implicates an intramolecular cyclization to a cyclopentenyl cation, according to an electrocyclic π2s + π2a conrotatory process, published in a recent paper (from the corresponding diacids). We have investigated the thermal behavior of the corresponding half-esters since; if the cyclization obeys to the proposed mechanism, the diacids, half-esters must also cyclize in a similar manner. Saponification of these led to γ-dilactones via intermediary cyclopropanes. Mechanistic pathways were investigated.

International audience; Marine invertebrates produce a large number of unique and structurally diversified natural products which represent a major source of bioactive molecules, particularly for pharmaceuticals leads. Several thousands of novel marine natural products exhibiting a wide range of bioactivities such as anticancer, antiviral, antifungal and antibacterial properties are listed. Since the early 1990s, the Chemistry Laboratory of Natural Substances and Food Sciences (LCSNSA) has been trying to gain a foothold in this field of research. The laboratory which is located at Reunion Island is at a strategic location for the research of natural bioactive molecules. Indeed, with a series of islands scattered in the western Indian Ocean along the southeast coast of Africa, Reunion Island belongs to a global biodiversity hotspot. This poster will therefore provide an outline of the contribution made by the LCSNSA to marine natural products research in the west of Indian Ocean. Over the last fifteen years, our research programs were more precisely concentrated on marine invertebrates from Reunion Island, Mayotte and Madagascar. Among the numerous marine invertebrates encountered in these areas, sponges, ascidians and soft corals have predominated in all our collection expeditions and have therefore received special attention from our research group. More than eighty new compounds showing relevant bioactivity, were isolated. However, this research is still at the very beginning and there are numerous areas that have not been investigated by the LCSNSA, particularly in the microbial environment. Indeed, there is an increasing evidence that many metabolites, are not produced by the animals themselves but by associated bacterial symbionts. In the future, the expansion of our research to biotechnology will be one of our key strategic challenges.

International audience; Marine ecosystems in active volcanic areas are regularly subject to natural hazardssuch as being covered by incandescent lava flows, acoustic phenomena caused bymicroseisms, temporary changes in physicochemical conditions of water bodiesand exceptional elevations of temperature. The Piton de la Fournaise (ReunionIsland) is one of the most active effusive volcanoes in the world with 27eruptions between 1998 and 2007 and a mean frequency, over a century, of aneruptive phase every 9 months. It provides a natural laboratory to study thecolonization of a blank substrate. Therefore, a project called BIOLAVE waslaunched in 2010 in order to study species and habitat diversity on the coastalmarine area of the volcano, including the first taxonomic inventory for thesoutheast side of the Island [1].One hundred fungal isolates were obtained from 1977 lava flow (-25m depth),2004 lava flow (-70m) and free water (-70m) as preliminary sampling. Density ofpropagules was as follows: 0.085/g free water (-70m), 20/g 2004 lava (–70m) and80/g 1977 lava (-25m) (MEA, PDA and Sabouraud media). These isolates shouldnow be identified using phenotypic characteristics and molecular biology.

International audience; Les extraits enrichis en phycocyanine de Spirulina platensis (spiruline) peuvent trouver denombreuses applications dans les domaines de l’alimentaire, de la pharmacologie, de lacosmétique et de la recherche. Seul colorant bleu naturel compatible avec l’alimentaire, laphycocyanine est également reconnue pour ses vertus antioxydantes, anti-inflammatoires ethépatoprotectrices.Cette étude a pour objectif de comparer différentes méthodes d’extraction de la phycocyaninede Spirulina platensis et d’analyser la stabilité de ces colorants dans les extraits. Les extraitsenrichis en phycocyanine ont été obtenus à l’aide de méthodes physiques(congélation/décongélation, vortex, ultrasons, micro-ondes, méthode accélérée par solvant -ASE), chimiques (HCl) et biochimiques (lysozymes, levures) à partir de spiruline sèche oufraîche produite au laboratoire et les résultats ont été comparés à des échantillons de spirulinecommerciale. Les extraits ont été analysés par spectrophotométrie et par HPLC- DAD. Lastabilité des pigments a été étudiée en suivant sa détérioration dans le temps (40 jours) sur desextraits conservés à 4°C et à 25°C dans différentes solutions tampons. Des analysescolorimétriques ont également été menées pour caractériser précisément la couleur despigments extraits.Le rendement en phycocyanine peut varier selon la méthode d’extraction, de 0.76 mg/g dematière sèche pour l’extrait obtenu par méthode chimique (spiruline commerciale) à 253.78mg/g pour l’extrait obtenu par méthode de congélation/décongélation à partir de matièrefraîche en présence de tampon phosphate. De manière générale, les extractions à partir dematière fraîche ont permis d’avoir les rendements les plus élevés. La stabilité des extraits esttrès sensible à la température de conservation : les extraits se conservent beaucoup pluslongtemps à 4°C, comparativement à ceux conservés à 25°C pour lesquels la concentration estquasi nulle après 40 jours de conservation. Les extractions par congélation/décongélation enprésence des tampons acétate de sodium (pH5) et citrate (pH6) ont par ailleurs montré uneaugmentation de la stabilité de la phycocyanine dans le temps. Enfin, l’extrait obtenu parméthode de congélation/décongélation à partir de matière fraîche en présence de tamponphosphate, qui a donné le meilleur rendement en phycocyanine, est l’extrait qui présentait lacouleur bleue la plus intense.En conclusion, parmi les 8 méthodes d’extraction testées, la méthode d’extraction parcongélation/décongélation, bien que moins rapide que les extractions par ASE ou par microondespar exemple, a montré la meilleure efficacité d’extraction du pigment bleu. Par ailleurs,les extraits de phycocyanine conservés à 4°C et à des pH plus acides se sont révélés les plusstables et les plus concentrés.

International audience; Cheeses harbor a complex microbiota, usually a succession of different microorganisms during milk coagulation and ripening. Surface-ripened cheeses are characterized by a ripening from the cheese surface to the interior due to the activity of both yeasts and bacteria. Many such cheeses are produced all over the world with Europe as a leader: Taleggio in Italy; Munster, Epoisses, Livarot in France; Limburger, Tilsit in Germany; Herve in Belgium [1]. The cheese microflora contributes to a large extent to the development of the typical flavor, texture, and color of the final product. Color is one of the major attributes which affects the consumer perception of quality. Pigments generated by the smear bacteria at the surface of cheeses were poorly studied, exception made for those of the bacteria Brevibacterium linens (aromatic carotenoids, isorenieratene and hydroxyl derivatives). Indeed, for a long time this bacterium has been considered the single source of the color of red-smear ripened soft cheeses. High-throughput sequencing revolutionized the field of microbial ecology, allowing for a more accurate identification of microbial taxa, including those which are difficult to culture and/or are present in low abundance, now revealing the highly diverse bacterial populations of cheese rinds, i.e. with up to 19 bacterial genera described in some cheeses.Arthrobacter bacteria have been isolated on surface-ripened cheeses and their pigments were found in cheese rinds [1]. The genus Arthrobacter is very complex in Nature with 80 species isolated from various environments and listed in the taxonomy, producing a great variety of pigments: orange and yellow (carotenoids –pioneering works in the early seventies [2]), blue and green (indigoidine, indochrome), red (porphyrins, carotenoids). The present study focuses on the chemical characterization of pigments biosynthesized by the cheese-ripening bacteria Arthrobacter arilaitensis.Lyophilized biomass was extracted with 3 x MeOH and 2 x MTBE, with sonication and centrifugation at each step. Samples were analyzed using the same solvent system (Solvent A: MeOH; Solvent B: MTBE) with the gradient conditions described in [1]. A fused core column Ascentis Express Supelco C18, (150 x 4.6 mm, particle size 2.7 m) and a Shimadzu Nexera HPLC-PDA-IT TOF system were used for the HPLC analyses. The UV-vis carotenoid profiles were similar for both strains investigated. Considering the UV-vis spectra (including fine structure), the APCI (-) and (+) mass spectra, and the elution order, 8 different carotenoids were tentatively identified. Four of them (sarcinaxanthin mono-glucoside pentaacetate, decaprenoxanthin di-glucoside, decaprenoxanthin mono-glucoside and decaprenoxanthin-C16:0) are possibly present in very low amount, and were only detected in the APCI (-) ionization mode. The other four free main carotenoids, decaprenoxanthin, sarcinaxanthin, 9-Z- decaprenoxanthin and 15-Z- decaprenoxanthin have quite clearly been characterized by both their UV-vis spectra and MS spectra in APCI (-) and (+) ionization mode. Arthrobacter arilaitensis species does indeed produce C50 carotenoids, and in particular, it mainly produces free all-E- decaprenoxanthin, and in minor amount two of its cis isomers, the 9-Z- decaprenoxanthin and 15-Z- decaprenoxanthin.This is in complete accordance with genomic data published about A. arilaitensis (whole genome sequencing [3]) and its Idi, CrtE, CrtB, CrtI, CrtEb, CrtYe and CrtYf carotenogenesis cluster, similar to the cluster of the decaprenoxanthin producing Corynebacterium glutamicum.[1]P. Galaup, A. Gautier, Y. Piriou, A. de Villeblanche, A. Valla, and L. Dufossé. Innov. Food Sci. Emerg. Technol., 8, 373-378 (2007).[2]N. Arpin, S. Liaaen-Jensen, and M. Trouilloud. Acta Chem. Scand., 26, 2524-2526 (1972).[3]C. Monnet et al. PLoS ONE, 5, e15489 (2010).

Poster communication, ASSET 2014, International Congress ‘Our food is our future, Food integrity & traceability conference, Belfast, UK, April 8-10, 2014; International audience; The determination of geographical origin is required for the traceability system of food products. One wayof tracing the source of a product is to analyse the bacterial communities present on the food samples.For this purpose, molecular techniques (such as PCR-DGGE) employing 16S rDNA profiles were used todetect variations in bacterial community structures of salts from various regions. Statistical analyses ofrDNA profiles revealed that distinct microbial communities were detected. The profiles of salt bacteriafrom different producing areas were different and specific for each location and could be used as a barcode to certify the geographical origin of salts. These profiles could serve as specific markers for a specificlocation. This method is proposed as a new traceability tool which provides salts with a unique bar codethat permits to trace back salts from store shelves to their original location of production.

Les extraits enrichis en phycocyanine de Spirulina platensis (spiruline) peuvent trouver denombreuses applications dans les domaines de l’alimentaire, de la pharmacologie, de lacosmétique et de la recherche. Seul colorant bleu naturel compatible avec l’alimentaire, laphycocyanine est également reconnue pour ses vertus antioxydantes, anti-inflammatoires ethépatoprotectrices.Cette étude a pour objectif de comparer différentes méthodes d’extraction de la phycocyaninede Spirulina platensis et d’analyser la stabilité de ces colorants dans les extraits. Les extraitsenrichis en phycocyanine ont été obtenus à l’aide de méthodes physiques(congélation/décongélation, vortex, ultrasons, micro-ondes, méthode accélérée par solvant -ASE), chimiques (HCl) et biochimiques (lysozymes, levures) à partir de spiruline sèche oufraîche produite au laboratoire et les résultats ont été comparés à des échantillons de spirulinecommerciale. Les extraits ont été analysés par spectrophotométrie et par HPLC- DAD. Lastabilité des pigments a été étudiée en suivant sa détérioration dans le temps (40 jours) sur desextraits conservés à 4°C et à 25°C dans différentes solutions tampons. Des analysescolorimétriques ont également été menées pour caractériser précisément la couleur despigments extraits.Le rendement en phycocyanine peut varier selon la méthode d’extraction, de 0.76 mg/g dematière sèche pour l’extrait obtenu par méthode chimique (spiruline commerciale) à 253.78mg/g pour l’extrait obtenu par méthode de congélation/décongélation à partir de matièrefraîche en présence de tampon phosphate. De manière générale, les extractions à partir dematière fraîche ont permis d’avoir les rendements les plus élevés. La stabilité des extraits esttrès sensible à la température de conservation : les extraits se conservent beaucoup pluslongtemps à 4°C, comparativement à ceux conservés à 25°C pour lesquels la concentration estquasi nulle après 40 jours de conservation. Les extractions par congélation/décongélation enprésence des tampons acétate de sodium (pH5) et citrate (pH6) ont par ailleurs montré uneaugmentation de la stabilité de la phycocyanine dans le temps. Enfin, l’extrait obtenu parméthode de congélation/décongélation à partir de matière fraîche en présence de tamponphosphate, qui a donné le meilleur rendement en phycocyanine, est l’extrait qui présentait lacouleur bleue la plus intense.En conclusion, parmi les 8 méthodes d’extraction testées, la méthode d’extraction parcongélation/décongélation, bien que moins rapide que les extractions par ASE ou par microondespar exemple, a montré la meilleure efficacité d’extraction du pigment bleu. Par ailleurs,les extraits de phycocyanine conservés à 4°C et à des pH plus acides se sont révélés les plusstables et les plus concentrés.

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International audience; The growth of Aspergillus niger and the growth characteristics of the cultures were detd. In addn., the phys. and chem. characteristics of the broth like pH, COD (COD), ashes are presented. It was interesting to find that the intensive growth of A. niger was obsd. in pure distillery spentwash (DSW) contg. no addnl. nutriments than the one present naturally in DSW. All the measured parameters, such as the total solids, suspended solids, ashes, COD and C/N, except for pH, were always higher in DSW from Reunion than in DSW from other countries. [on SciFinder(R)]

International audience; no abstract

International audience; no abstract

A filamentous fungus, Fusarium poae INRA 45, was grown in two liquid Czapek-type media (a Czapek medium, and a yeast extract plus casaminoacids-enriched Czapek medium). Eight γ-lactones, i.e., γ-penta-, γ-octa-, γ-nona-, γ-deca-, and γ-dodecalactone, (6Z)-γ- and (6E)-γ-dodecenolactones, and a di-unsaturated γ-dodecalactone, were tentatively, or conclusively, identified by capillary gas chromatography (GC) and coupled GC-MS, in the volatile fractions of the cultures. Kinetics of the formation of γ-decalactone, (6Z)-γ- and (6E)-γ-dodecenolactones, (three major lactones), and γ-dodecalactone (a minor lactone) were quantitatively studied by computerized GC integration. Variations of the (R/S) ratios of the lactone enantiomers were quantitatively studied by computerized multidimensional gas chromatography (MDGC) integration. The levels of the lactones were superior in the enriched Czapek-type medium to those of the Czapek medium, but the compositions of these media did not influence significantly the (R/S) ratios of these lactones. Formation of the enantiomers is discussed in terms of metabolism of potential precursors.

Marine-derived fungi that inhabit severe changing environments have gained increasing interest for their ability to produce structurally unique natural products. Fungi belonging to the Talaromyces and the close Penicillium genera are among the most promising microbes for bioactive compound production, including colored metabolites. Coupling pigment producing capability with bioactive effectiveness would be a valuable challenge in some specific fields such as dyeing, cosmeceutical, or food industries. In this sense, Talaromyces albobiverticillius 30548, a red pigment producing strain, has been isolated from the marine environment of Reunion Island, Indian Ocean. In this research, we analyzed the effect of temperatures (21&ndash, 27 &deg, C) and salinity levels (0&ndash, 9%) on fungal growth and pigment production. Maximum pigment yield was obtained in non-salted media, when cultured at 27 &deg, C after 10 days of submerged fermentation in PDB. However, maximum dry biomass production was achieved at stressed condition with 9% sea salts concentrated media at the same temperature. The results indicate that salinity of the culture media positively influences the growth of the biomass. Inversely, pigment production decreases with increase in salinity over 6%. Color coordinates of secreted pigments were expressed in CIELAB color system. The hue angles (h&deg, ) ranged from red to yellow colors. This indicated that the color distribution of fungal pigments depends on the salinity in the culture media. This study emphasizes the impact of abiotic stress (salt and temperature) on the growth and metabolome of marine-derived fungal strains.