La recrudescence des maladies dégénératives ces dernières décennies dans le monde a amené plusieurs chercheurs et médecins à médiatiser les antioxydants à cause des vertus qu’on leur prête: de la protection contre les maladies cardiovasculaires à la prévention de certains cancers. Le présent travail a été mené avec pour objectif principal d’évaluer le pouvoir antioxydant des épices entrant dans la préparation de la sauce en vue du développement d’un complément alimentaire nutraceutique. Pour ce faire, vingt épices largement consommées ont été choisies sur la base d’une enquête exploratoire menée au Cameroun. Les différentes épices réduites en poudres ont été analysées pour leurs teneurs en composition nutritionnelle. Le pouvoir antiradicalaire in vitro des extraits méthanoliques des différentes épices a été déterminé ainsi que le pouvoir anti-inflammatoire et antistress sur des rats adultes à stress induit. Les résultats obtenus ont montré des variations très significatives de la composition des épices. L’activité antioxydante utilisant la méthode au N’ N-diphényl-N’-picrylhydrazyl (DPPH), au « trolox equivalent antioxidant capacity » (TEAC) et le pouvoir réducteur total (PRT) ont révélé que Z. leprieurii et D. glomerata présentent les activités particulièrement élevées. Les extraits de ces deux épices ont servi de base à la préparation de mélange dont l’effet a été testé sur des rats mâles à inflammation induite. Les résultats obtenus ont montré que les épices individuelles et leur mélange à des doses de 100 mg/kg et 150 mg/kg présentent une activité anti-inflammatoire importante comparable à ceux commerciaux: inodméthacine, déxaméthasone et célécoxib. La variation de la teneur en malonaldéhyde (marqueur de l’oxydantion lipidique) a révélée l’action antioxydante in vivo des extraits, démontrant ainsi leur potentiel dans le développement de compléments alimentaires à effet antistress / Increasing evidences from current research point to the fact that certain disease conditions can be prevented through the consumption of antioxidant rich foods. The present work was carried out to evaluate the antioxidant potentials of twenty Cameroonian spices commonly used in some Cameroonian cuisine. The nutritional properties of spices, the in vitro antioxidant potential of their methanolic extracts as well as the in vivo antioxidant potential of the methanolic extracts of some selected samples were determined. The antioxidant activity brought about by N’ N-diphenyl-N’-picrylhydrazyl (DPPH), «trolox antioxidant equivalent capacity» (TEAC) and the total reduction power (PRT) methods have revealed that Z. leprieurii and D. glomerata presented the highest activities. The extracts of the two spices were used to prepare a mixture whose effect was tested on male rats with induced inflammation. The results obtained indicate that the individual spices and their mixture at 100 mg/kg and 150 mg/kg present an important anti-inflammatory activity comparable to that of commercial anti-inflammatory like indomethacin, dexamethasone and celecoxib. The variation of malondialdehyde content (a lipidic oxidant marquer) revealed the in vivo antioxidant action of extracts, thus demonstrating their potential for the development of functional foods with anti-stress effect

La mousse est une caractéristique organoleptique majeure des vins effervescents. Dans le cadre d’une meilleure maîtrise des propriétés moussantes des vins de Champagne, l’objectif de ce travail est de mieux comprendre l’impact de la maturité des raisins et du fractionnement des jus au pressurage sur la composition des moûts et des vins, en particulier sur les protéines, et la relation avec la moussabilité des vins.Au cours de la maturation de raisins sains Chardonnay et Pinot noir de deux millésimes, les caractéristiques œnologiques des moûts évoluent pour un TAP compris entre 4% et 11% vol. Une augmentation de la teneur en protéines est aussi montrée au cours de la maturation des baies. De plus, pour des raisins vendangés à « maturités industrielles », des changements essentiels de la composition biochimique des moûts, ayant un TAP compris entre 8% et 11% vol., sont observés.Une étude de la maturité de raisins Chardonnay et Pinot meunier de trois millésimes, a montré que des raisins plus mûrs, et sains, donnent des vins de base avec des teneurs en protéines totales plus élevées, ayant une meilleure moussabilité que des vins issus de raisins moins mûrs. Les analyses statistiques montrent des corrélations positives significatives entre différentes caractéristiques œnologiques des moûts et des vins de base et, pour la première fois, une corrélation entre la moussabilité et la teneur en protéines des vins, en relation avec la maturité, a été montrée. Au-delà de la maturité des raisins, la teneur en protéines et la moussabilité des vins peuvent être fortement influencées, dans la notion de Terroir, par le couple cépage/parcelle et le climat du millésime.L’étude du fractionnement des jus au pressurage, réalisée sur les cépages Chardonnay, Pinot noir, Pinot meunier et cinq millésimes, montre une évolution générale des caractéristiques des moûts et des vins, au cours du pressurage à l’échelle industrielle et au laboratoire. La composition des moûts et des vins peut être fortement influencée par la variabilité de la parcelle, de la maturité, du millésime, de l’état sanitaire des raisins, mais faiblement affectée par l’échelle et le type de pressoir. Ces sources de variabilités conduisent à des différences de teneur en protéines et de propriétés moussantes pour les vins de base champenois. / Foam is a major sensory characteristic of sparkling wines. As part of better controlling the foaming properties of Champagne wines, the goal of this work is to better understand the impact of grape maturity and press fractioning on the composition of grape juices and base wines, especially on the proteins, and their relationships with wines’ foamability.During the maturation of healthy grapes (Chardonnay and Pinot Noir of two vintages), the oenological characteristics of musts evolve in a TAP range from 4% to 11% vol. An increase in protein content was also showed during the ripening of grape berries. In addition, for the grapes harvested at ‘industrial maturity’, essential changes in the biochemical composition of musts were observed with a TAP between 8% and 11% vol.The study of grape maturity that performed on Chardonnay and Pinot Meunier grapes of three vintages, showed that riper and healthy grapes could give their corresponding base wines with higher total protein contents, and better foamability than those wines made from less ripen grapes. Statistical analyses showed significant positive correlations between different oenological characteristics of musts and base wines and, for the first time, a correlation between foamability and protein content of wines, in relation to grape maturity, has been shown. Except for the grape maturity, the protein content and the foamability of Champagne base wines could be strongly influenced, in the concept of ‘Terroir’, by the pair grape variety/vineyard and the climate of the vintage.The study of the press fractioning of grape juices, carried out on Chardonnay, Pinot Noir, Pinot Meunier of five vintages, showed a general evolution of the characteristics in musts and wines, during the pressing cycle that realized on industrial and laboratory scale. The composition of musts and their corresponding wines could be strongly influenced by the variability of vineyards, grape maturity, vintage and the health condition of grapes, but hardly affected by the scale and the type of press. Those sources of variability could lead to differences in protein content and foaming properties for Champagne base wines.

L'installation de récifs artificiels est une solution classiquement proposée pour soutenir la petite pêche artisanale. C'est dans ce but qu'a été déployé dans la baie de Marseille le plus grand ensemble de récifs artificiels de Méditerranée. Ce système offre une opportunité de comprendre le fonctionnement trophique de ces structures par (1) la caractérisation des sources de matière organique (MO) (2) la détermination de leur utilisation par les consommateurs et (3) leur devenir au sein des réseaux trophiques. Ces questions ont été appréhendées à l'aide des isotopes stables du C et du N, de la caractérisation biochimique des sources de MO et de l'analyse des contenus stomacaux des poissons.Les sources de MO présentent des différences isotopiques et biochimiques, reflet de leurs fonctionnements différents. La MO particulaire en suspension est un pool variable influencé par les apports allochtones et soumis aux forçages climatiques. Elle est la source principale de MO sur les récifs artificiels. La production primaire benthique est très hétérogène et de qualité nutritionnelle faible. Elle contribue aux réseaux trophiques des récifs par le biais des détritus qu'elle produit. Enfin, la MOS est un pool détritique de faible qualité nutritionnelle. Les récifs artificiels ne modifient pas la structure et le fonctionnement des communautés naturelles de poissons et leur offrent des ressources alimentaires variées et importantes. L'ensemble des résultats acquis, via les isotopes stables et les contenus stomacaux, montrent que les récifs artificiels sont des producteurs de biomasse à partir des productions primaires locales. / Artificial reefs are a classical tool used to sustain small scale fisheries. In Marseille's Bay, the largest Mediterranean artificial reef system was deployed for this purpose. This system is a valuable opportunity to better understand the trophic functioning of artificial reefs, by (1) characterizing the organic matter (OM) sources, (2) determining how they are used by low trophic level consumers and (3) following their fate in the trophic networks. These issues were assessed by three approaches:C and N stable isotope ratios, biochemical composition of OM sources and fish stomach content.OM sources display isotopic and biochemical differences reflecting their functioning. Suspended POM is variable, under the influence of allochtonous inputs and controlled by climatic forcing. POM represents the main OM source of the artificial reef food webs. The benthic primary production has heterogeneous C and N stable isotope ratios and exhibits mainly high insoluble carbohydrates contents. Benthic primary production is integrated into trophic networks mainly in the form of detritus. Eventually the sediment organic matter is a detrital pool, characterized by a low variability and a poor nutritional quality.Artificial reefs do modify the organization and the functioning of natural fish communities, and provide diversified and important food resources. Stable isotope and stomach content analyses confirm the consumption of artificial reef invertebrates by small carnivorous fishes, preyed themselves by piscivorous predators. All these results confirm that artificial reefs can efficiently increase fish biomass by local production based on phytoplanktonic and local benthic OM sources.

Orientador: Lucia Helena Sipauba Tavares / Resumo: A microalga Haematococcus pluvialis apresenta elevado interesse biotecnológico e comercial devido sua capacidade de síntese de compostos de alto valor e composição nutricional rica em proteínas, aminoácidos e outros compostos. Dentre os entraves em sua produção comercial, a obtenção de elevada biomassa tem sido o foco de diversas pesquisa que buscam otimizar o cultivo desta espécie. O cultivo mixotrófico é uma ferramenta que pode auxiliar na obtenção de elevadas produtividades, no entanto a fonte de carbono utilizada nestes cultivos deve ser adequada e disponibilizada de forma correta para completa absorção. O melaço de cana de açúcar é uma fonte de carbono rica em sacarose e nutrientes podendo ser empregado no cultivo de H. pluvialis, no entanto, requer pré-tratamento antes de seu uso. A hidrólise auxilia na redução das moléculas de sacarose em glicose e frutose, aumentando a disponibilidade de carbono e facilitando sua assimilação. Comparado ao melaço in natura, a hidrolise do melaço demonstrou melhores resultados aumentando a produtividade e alta composição bioquímica. Outra ferramenta importante utilizada na otimização dos cultivos algais em condições mixotróficas é o uso de ciclos de luz, uma vez que a luminosidade está relacionada diretamente ao metabolismo algal auxiliando na assimilação dos nutrientes e do carbono. O período de iluminação fornecida varia de espécie para espécie, podendo ou não ser necessário. Neste estudo e para estas condições de cultivo, foram obser... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Haematococcus pluvialis microalgae displays high biotechnological and commercial interest due to its capacity to synthesize high nutritional value in protein, amino acids and other compounds. Besides the difficulties in commercial production, the obtaining of high biomass amounts has been the objective of several researches which seek to optimize the production of this species. The mixotrophic culture is a tool which may improve the obtention of higher productivity. However, the carbon source for the cultures have to be adequate and has to be in an available form in order to be completely absorbed. The cane molasse is a carbon source rich in saccharose and nutrients and might be employed in H. pluvialis culture. Nevertheless, it requires a pre-treatment for its use. The hydrolysis promotes the reduction of saccharose molecules into glycose and fructose, improving the carbon availability and assimilation. In comparison to in natura molasses, the hydrolysis improved the results by increasing productivity. Light cycle is another important tool for algae culture in mixotrophic conditions, since light is directly related to the algae metabolism, which improves the carbon and nutrients assimilation. The light interval varies according to species and may or may not be necessary to be employed. In this study, an increase in biomass and biochemical composition was observed when H. pluvialis was exposed to light cycles. The best results were obtained with a 20:4 hours cycle (light/... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2016-06-02T19:31:59Z (GMT). No. of bitstreams: 1 3988.pdf: 740550 bytes, checksum: c474fd35724dbe7bdd263dbd50611faf (MD5) Previous issue date: 2011-09-02 / Financiadora de Estudos e Projetos / Metal toxicity to microalgae is dependent on environmental conditions, evolutionary history of the microalgae, and previous exposure of the organism to the specific metal. Also, it is importantly influenced by the physiological condition of the algae in the moment of metal exposure. In this research we investigated several combinations of phosphorus (P) and copper (Cu) concentrations on the biochemical composition and Cu toxicity to Chlorella vulgaris. Due to its known toxicity, copper was considered in its free Cu2+ ions specie. Because microalgae physiology reflects the environmental conditions, but it also stores some of the inorganic nutrients, previous to Cu spike in the cultures, the algae were acclimated to each treatment s specific P concentration to be tested in combination with Cu. We considered cells were acclimated to a specific P concentration after its growth rate had been stabilized for at least four generations, always transferring the cells while in the beginning of the exponential growth phase. Biomass and physiological parameters analyzed were cell number (cell.mL-1), chlorophyll-a concentration, dry weight, lipid classes (Iatroscan TLC/FID), and total cellular proteins and carbohydrates at several combinations of P/Cu. The P concentrations tested were 5.0x10-5, 2.5x10-5, 5.0x10-6 and 1.0x10-6 mol.L-1 and the free Cu2+ ions concentrations ranged within 1x10-10 and 5x10-8 mol.L-1, and were determined through ion selective electrode (ISE). Our results showed that Cu toxicity to C. vulgaris increased at low P. Carbohydrate, protein and lipid productions were in general triggered at low P and high Cu, with some exceptions. TAG was the lipid class most affected by stressing situations. AMPL and PL were the lipid classes with the higher percent composition amog the classes; HC, WE and ST were present in minor amounts even under stressing situations. / As microalgas apresentam uma estreita relação com o meio circundante, sendo a parede e membrana celulares a via de entrada dos compostos dissolvidos. Mas, o modo como as algas interagem com os metais no ambiente, depende grandemente da especiação química do elemento. Portanto, a toxicidade de metais para microalgas relaciona-se, não somente com sua história evolutiva e condição fisiológica, mas também com a forma em que o metal é encontrado no ambiente. Nesta pesquisa, investigamos o efeito de diversas combinações de concentrações de fosfato (P) e cobre (Cu) na toxicidade do micronutriente e na composição bioquímica da microalga de água doce Chlorella vulgaris. O cobre foi analisado na forma iônica livre pois esta é uma das espécies de maior toxicidade para as algas. Antes da adição de cobre, a microalga foi aclimatada para a concentração de fosfato do respectivo tratamento experimental (P:Cu). As células foram consideradas aclimatadas para uma concentração específica de P após sua taxa de crescimento ter sido estabilizada por quatro gerações, sempre transferindo as células em fase inicial de crescimento exponencial. Para cada tratamento efetuado, os parâmetros de biomassa e fisiológicos analisados foram número de células por mL, concentração de clorofila-a, biomassa seca, classes lipídicas, através do equipamento (Iatroscan TLC/FID), proteínas e carboidratos celulares totais. As concentrações de P testadas foram 5,0x10-5, 2,5x10-5, 5,0x10-6 e 1,0x10-6 mol.L-1 e a amplitude de concentração de ions Cu2+ livres ficou entre 1x10-10 and 5x10-8 mol.L-1. Cobre livre foi determinados através de eletrodo seletivo ao íon (ISE) cobre. Nossos resultados mostraram que a toxicidade de Cu para C. vulgaris foi afetada pela concentração de fosfato no meio de cultura. Em baixas concentrações de fósforo, houve a maior toxicidade do Cu, aumento na produção de carboidratos e de lipídios. A análise das classes lipídicas revelaram que os hidrocarbonetos alifáticos (HC), ésteres de cera (WE) e esterol (ST) tiveram sua síntese ativada em concentrações tóxicas de Cu e de baixo fósforo. Similarmente, a síntese proteica aumentou sob essas condições, com a maior quantidade de síntese proteica obtida na menor concentração fósforo testada.

Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-10-20T19:44:51Z No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T18:43:52Z (GMT) No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T18:44:01Z (GMT) No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) / Made available in DSpace on 2016-11-08T18:44:08Z (GMT). No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) Previous issue date: 2016-03-07 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / The hatchery is now the main obstacle of aquaculture. Live food, especially zooplankton, is essential in the first life stages of fish. However, there are difficulties in obtaining sufficient biomass. The Anostraca Dendrocephalus brasiliensis, known as “branconeta”, has great potential for use in national aquaculture. In this study, experiments were conducted in controlled conditions in order to obtain: I) the best conditions for hatching of resistant cysts, evaluating the cyst density in the sediment, temperature and pH of the water, and cysts dehydration time; II) identification of the early stages of life, focusing on the length and time to maturity, and we also investigate the main factors that influence the development of the early stages and; III) semiintensive production, the organisms were grown during winter and summer, with two different diets and subsequent analysis of the biochemical composition of organisms grown in these conditions. Hatching occurs in low proportions, and is mainly influenced by the density of cysts present in the sediment, and show some tolerance to different levels of temperature and pH. The average time to reach adulthood was ten days and during the early stages, we observed that some individuals have delayed hatching. Among the environmental variables, temperature and conductivity play a major role in the growth during this period, along with the food, which must be provided from the third day. In semi-intensive farming conditions, we found that large amounts of food promote greater growth in length, both in summer and winter, however, during the winter, low amounts of food provide greater survival. In biochemical analysis, individuals grown with a low amount of food had higher proportion of protein, values higher than those found in Artemia sp. We also detected the presence of polyunsaturated fatty acids, which are of great interest in organisms to be used as live food for fish. In general, D. brasiliensis can be regarded as a suitable species for use in aquaculture due to: ease handling of cysts, since cysts present in the sediment are sufficient for obtaining large populations; growth rate and high tolerance to ambient changes, not requiring great efforts in keeping the culture medium and; nutritional quality, with high concentration of proteins and the presence of polyunsaturated fatty acids. / A larvicultura é hoje o principal entrave da aquicultura. O alimento vivo, em especial zooplanctônico, é essencial nas fases jovens de peixes. No entanto, há dificuldades em se obter biomassa suficiente. O Anostraca Dendrocephalus brasiliensis, conhecido como branconeta, tem grande potencial de utilização na aquicultura nacional. No presente estudo, foram realizados experimentos controlados a fim de se obter: I) melhores condições para eclosão dos cistos de resistência, avaliando a densidade de cistos no sedimento, temperatura e pH da água, e tempo de desidratação dos cistos; II) identificação dos estágios iniciais de vida, com enfoque no comprimento e tempo até a maturidade, além de investigarmos os principais fatores que influenciam o desenvolvimento das fases iniciais e; III) produção semi-intensiva, com cultivos realizados durante o inverno e o verão, com dois regimes alimentares distintos e posterior análise da composição bioquímica dos organismos cultivados nestas condições. A eclosão ocorre em baixas proporções e é influenciada principalmente pela densidade de cistos presente no sedimento, tendo certa tolerância a diferentes níveis de temperatura e pH. O tempo médio para se atingir a idade adulta foi de dez dias e durante as fases inicias, observamos que alguns indivíduos apresentam eclosão tardia. Dentre as variáveis ambientais estudadas, temperatura e condutividade desempenham papel principal no crescimento durante esse período, juntamente com a alimentação, a qual deve ser fornecida a partir do terceiro dia. Em condições de cultivo semi-intensivo, constatamos que grandes quantidades de alimento promovem maior crescimento em comprimento, tanto no verão quanto no inverno, contudo, durante o inverno, baixas quantidades de alimento conferem maior sobrevivência. Na análise bioquímica, os indivíduos cultivados em regime com baixa quantidade de alimento apresentaram maior proporção de proteínas, valores estes maiores do que aqueles encontrados em Artemia sp. Também detectamos a presença de ácidos graxos poliinsaturados, que são de grande interesse em organismos a serem utilizados como alimento vivo para peixes. De modo geral, D. brasiliensis pode ser considerada uma espécie propícia ao uso na aquicultura, devido à: facilidade no manejo de cistos, uma vez que cistos presentes no sedimento são suficientes para obtenção de grandes populações; alta taxa de crescimento e tolerância às variações ambientes, não exigindo grandes esforços na manutenção do meio de cultivo e; qualidade nutricional, com alta concentração de proteínas e presença de ácidos graxos poliinsaturados. / 2008/02078-9

Trotz der Schlüsselstellung heterotropher Protisten als Bindeglied zwischen dem mikrobiellen und dem klassischen Nahrungsnetz ist noch wenig über ihre biochemische Zusammensetzung und ihren Nährwert bekannt. In der vorliegenden Doktorarbeit wurde untersucht ob die biochemische Zusammensetzung von Protisten (1) von deren Nahrungsgrundlage (Alge oder Bakterien) und Ernährungsweise (Autotrophie, Mixotrophie oder Heterotrophie) abhängt und (2) ihre Nahrungsqualität für räuberisches Rotatorien (Keratella quadrata) bedingt. Die Fettsäure-, Sterol- und Aminosäurezusammensetzung vier heterotropher Protisten spiegelte generell die ihrer Nahrung wider. Es trat jedoch eine Akkumulation dieser biochemischen Substanzen in den Protisten auf. Auch die Ernährungsweise eines Flagellaten (Ochromonas sp.) beeinflusste stark dessen biochemische Zusammensetzung, insbesondere die Konzentrationen an mehrfach ungesättigten Fettsäuren (PUFAs). Bei der Untersuchung des Nährwertes vier heterotropher Protisten für K. quadrata wurden signifikante Korrelationen zwischen verschiedenen PUFAs, drei Sterolen und einer Aminosäure (Leucin) der Protisten und der Eiproduktion der Rotatorien festgestellt. Auch die experimentelle Supplementierung eines Flagellaten mit einer PUFA (Docosahexaensäure, DHA) erhöhte seinen Nährwert für die Rotatorien signifikant. Die Ergebnisse verdeutlichen die Fähigkeit heterotropher Protisten, die biochemische Zusammensetzung organischer Materie schon auf einer unteren Ebene des aquatischen Nahrungsnetzes zu verändern, nämlich beim Übergang zwischen Algen/Bakterien und dem Mesozooplankton. Hier können biochemische Änderungen weitreichende Folgen für den Stoff- und Energiefluß des gesamten Nahrungsnetzes nach sich ziehen. / Heterotrophic protists are an important link between the microbial and the classical food web. However, little is known about their biochemical composition and nutritional quality as prey. In this thesis, I analysed (1) whether the biochemical composition of the protists depends on their dietary resources (bacterial or algal food) or trophic mode (autotrophy, mixotrophy or heterotrophy), and (2) whether the biochemical composition of protists determines their nutritional quality as prey for a rotifer species (Keratella quadrata). The fatty acid, sterol, and amino acid composition of four heterotrophic protists generally resembled the dietary composition, but the protists accumulated these compounds. Moreover, the trophic mode strongly affected the composition of a flagellate (Ochromonas sp.), especially that of polyunsaturated fatty acids (PUFAs). When investigating the nutritional quality of four protist species for K. quadrata, several PUFAs, three sterols (desmosterol, ergosterol, stigmastanol), and one amino acid (leucine) of the protists were significantly correlated with the rotifer’s egg production. Moreover, the nutritional quality of a heterotrophic flagellate for the rotifer was significantly enhanced by artificially supplementing the flagellate with a PUFA (docosahexaenoic acid, DHA). The thesis highlights the ability of heterotrophic protists to modify the biochemical composition of organic matter at an early stage in aquatic food webs, i.e. at the interface between algae/bacteria and mesozooplankton. Biochemical modifications at this stage may profoundly affect matter and energy transfer through the entire food web.