Made available in DSpace on 2016-08-19T17:47:13Z (GMT). No. of bitstreams: 1 Dissertacao Milena.pdf: 1663590 bytes, checksum: 5d3902c65da1f4c4c0f86d5b42becd6d (MD5) Previous issue date: 2013-05-14 / FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO / Phytotherapy, for being traditional practice of health recognized in several scientific studies and for World Health Organization, has become as an pharmacological alternative well accepted and accessible to the world s populations. As a result of this therapeutic practice consolidation, several plant species and their products are commercialized at fairs and public markets. The specie Schinus terebinthifolius Raddi, popularly known as aroeira, is among the plants widely consumed, due to its properties anti-inflammatory, healing and antibacterial. Thus, this study aims to evaluate the quality of commercial samples of aroeira, acquired in public markets in the city of São Luís - MA. For the study were used aroeira's barks acquired in twelve public markets, as well as barks obtained of a specimen previously identified in herbarium, used as reference sample of the specie Schinus terebinthifolius Raddi. Was performed analysis morphological (macroscopic) and anatomical (microscopic) of the cross sections and powders obtained from the barks, phytochemicals tests, evaluation of moisture content and antibacterial activity by the methods of broth dilution and agar diffusion. After macroscopic analysis, six commercial samples showed morphological aspects different from reference sample. With regard to microscopic analysis was demonstrated the authenticity of five commercial samples, by comparison with the plant reference sample and information in the literature. In Phytochemical analysis, the reference sample showed the major constituents characteristic of the species, however, the commercial samples analysis, differences were found related, mainly, the analysis of tannins and saponins. The differences observed in this evaluation may reflect the influence of intrinsic and extrinsic factors on the chemical composition of plant species. The determination of moisture in the commercial samples analyzed showed that five had moisture content above the maximum limit allowed for barks, being, therefore, reproved in thismcriterion. In the evaluation of antibacterial activity, all samples showed some degree of activity for Staphylococcus aureus ATCC 25923, however, only six were also active against Escherichia coli ATCC 25922, four of those considered authentic in the microscopic analysis. The verification of poor quality of herbal drugs marketed for therapeutic purposes demonstrates the need for development of inspection programs, surveillance and quality control of these drugs, aiming, thus, consumer safety. / A fitoterapia, por ser prática tradicional de saúde reconhecida em diversos estudos científicos e pela Organização Mundial da Saúde, tem se constituído como uma alternativa medicamentosa bem aceita e acessível aos povos do mundo. Como consequência da consolidação desta prática terapêutica, várias espécies vegetais e seus produtos são comercializados em feiras e mercados públicos. A espécie Schinus terebinthifolius Raddi, popularmente conhecida como aroeira, está entre as plantas de grande consumo devido à suas propriedades anti-inflamatória, cicatrizante e antibacteriana. Assim, o objetivo deste estudo foi avaliar a qualidade de amostras comerciais de aroeira, adquiridas em mercados públicos da cidade de São Luís - MA. Para o estudo foram utilizadas cascas de aroeira adquiridas em doze mercados públicos, bem como cascas obtidas de um exemplar previamente identificado em herbário, utilizadas como amostra referência da espécie S. terebinthifolius Raddi. Realizou-se análise morfológica (macroscópica) e anatômica (microscópica) das secções transversais e dos pós obtidos das cascas, testes fitoquímicos, avaliação do teor de umidade e da atividade antibacteriana pelos métodos de diluição em caldo e difusão em ágar. Após análise macroscópica, seis amostras comerciais apresentaram aspectos morfológicos diferentes da amostra referência. No que se refere à análise microscópica, ficou demonstrado a autenticidade de cinco amostras comerciais, através de comparação com a amostra referência e de informações contidas em literatura. Na análise fitoquímica, a amostra referência apresentou os principais constituintes característicos da espécie, no entanto, na análise das amostras comerciais, constatou-se diferenças relacionadas, principalmente, a análise de taninos e saponinas. As diferenças observadas nesta avaliação podem ser reflexo da influência dos fatores intrínsecos e extrínsecos sobre a composição química de espécies vegetais. A determinação de umidade nas amostras comerciais analisadas revelou que cinco apresentavam teor de umidade acima do limite máximo permitido para cascas, ficando, portanto, reprovadas neste critério. Na avaliação da atividade antibacteriana, todas as amostras revelaram algum grau de atividade para Staphylococcus aureus ATCC 25923, no entanto, apenas seis foram ativas também contra Escherichia coli ATCC 25922, quatro dessas consideradas autênticas na análise morfoanatômica. A comprovação da má qualidade de drogas vegetais comercializadas com fins terapêuticos demonstra a necessidade de desenvolvimento de programas de fiscalização, vigilância e controle de qualidade dessas drogas, objetivando, assim, a segurança do consumidor.

Syzygium cordatum is a medicinal plant indigenous to South Africa and Mozambique, commonly used to treat stomach aches, diabetes, respiratory problems and tuberculosis. In spite of the folklore use, adequate scientific data to credit its widespread traditional use is lacking. The objectives of this study were: to evaluate and validate scientifically the successful therapeutic claims by traditional medicine practitioners that Syzygium cordatum is effective in treating diarrhoea and diabetes / to determine the effects of the plant extract on gastrointestinal transit of a charcoal meal in mice / to determine the effects on castor oilinduced intestinal fluid accumulation / to determine the safety profile of the plant by carrying out acute toxicology study and to carry out preliminary screening of the active compounds present in the plant using standard phytochemical analytical procedures. The aqueous leaf extract of Syzygium cordatum (3.125 -50mg/kg, p.o) significantly reduced the faecal output caused by castor oil (0.7ml). All the doses used, reduced faecal output from 100% produced by castor oil to between 40 and 61%. S.cordatum (6.25 &ndash / 50mg/kg, p.o) significantly and in a dose dependent manner, delayed the onset of castor oil-induced diarrhoea.

Syzygium cordatum is a medicinal plant indigenous to South Africa and Mozambique, commonly used to treat stomach aches, diabetes, respiratory problems and tuberculosis. In spite of the folklore use, adequate scientific data to credit its widespread traditional use is lacking. The objectives of this study were: to evaluate and validate scientifically the successful therapeutic claims by traditional medicine practitioners that Syzygium cordatum is effective in treating diarrhoea and diabetes / to determine the effects of the plant extract on gastrointestinal transit of a charcoal meal in mice / to determine the effects on castor oilinduced intestinal fluid accumulation / to determine the safety profile of the plant by carrying out acute toxicology study and to carry out preliminary screening of the active compounds present in the plant using standard phytochemical analytical procedures. The aqueous leaf extract of Syzygium cordatum (3.125 -50mg/kg, p.o) significantly reduced the faecal output caused by castor oil (0.7ml). All the doses used, reduced faecal output from 100% produced by castor oil to between 40 and 61%. S.cordatum (6.25 &ndash / 50mg/kg, p.o) significantly and in a dose dependent manner, delayed the onset of castor oil-induced diarrhoea.

Five separate field experiments were conducted across different environmental locations in Texas for the purpose of quantifying concentrations of different phytochemical groups (ascorbic acid, capsaicinoids, and flavonoids) within various pepper species, as well as, to identify the most optimum environment to promote expression of the aforementioned phytochemical. Depending on the particular experiment, quantitative measurements were then used in more detail in one of three ways: for identification of the most superior individuals and optimum environmental locations to express elevated concentrations of a particular phytochemical (first three experiments), to calculate heritability and % heterosis estimates for various fruit characteristics and phytochemical levels (fourth experiment), or for use in a specific biotechnology technique to potentially identify a molecular marker linked to elevated levels of ascorbic acid (AA) and flavonoids (quercetin and luteolin) (fifth experiment). In the first experiment, significant differences in fruit weight, capsaicin, and dihydrocapsaicin (DHC) were revealed in fruit tissue of five Habanero (Capsicum chinense) hybrids in comparison to a popular, commercial check (Kukulkan F1) after being grown across three different environmental locations (College Station, Uvalde, and Weslaco). Fruit grown at the Weslaco location was found to be larger and contained more capsaicin and DHC than those produced in Uvalde or College Station. While flavonoid contents were variable and low in all genotypes and locations, a few hybrids showed some potential for use in future crossing schemes to compete against the commercial check. Our results further suggested that variation in phytochemicals in fruit tissue of Habanero genotypes can be exploited by selecting in an appropriate environment. In the second experiment, analysis of four jalapeño hybrids in comparison to three commercial checks (Dragon, Ixtapa, and J1845), as well as, two cayenne hybrids in comparison to one commercial check (Mesilla) were compared after growing in three different locations (Amarillo, College Station, and Uvalde). Results demonstrated that the College Station location contributed to production of fruit containing higher concentrations of both AA and flavonoids, while those grown in Amarillo produced fruit with higher capsaicinoids. As expected, cayenne samples contained more AA and flavonoids than jalapeño samples. In comparison to the commercial jalapeño checks, all jalapeño hybrids generally expressed less capsaicinoids. With respect to AA and flavonoid concentrations, a few jalapeño hybrids proved to have some potential to compete against their respective commercial cultivars. For the cayenne market, one genotype revealed its potential use in mild markets and for farmers interested in a new hybrid expressing both appreciable levels of phytochemicals, as well as, more visually aesthetic attributes. Statistical analyses from the third experiment found all the F-values for each characteristic to be significant except the Location x Genotype (L x G) component for fruit wall thickness. For this experiment, a total of 21 different C. annuum (jalapeño, Serrano, and cayenne) genotypes were evaluated after growing in two diverse environmental locations (Uvalde and Weslaco). In general, peppers grown in Weslaco produced fruit with higher concentrations of AA and capsaicinoids, with a few exceptions, while fruit grown at Uvalde generally was larger in size and contained higher concentrations of flavonoids. In comparison to their respective commercial checks (jalapeño – Dragon, Tormenta; Serrano – Halcon, Magnum45; cayenne – Mesilla), a few hybrids were arguably more desirable for their respective markets with respect to different fruit measurements, AA, capsaicinoid, and flavonoid concentrations. This evidence further suggested the potential benefit this material could have for growers interested in replacing current material in the industry and to more successfully provide consumers with a healthier ingredient to better sustain their lives. In the fourth experiment, results confirmed our hypotheses that paprika type material has higher AA and flavonoid concentrations than Serrano peppers, while the opposite is possible for capsaicinoid expression. For this experiment, our goal was to identify the relative ease of incorporating different traits of interest into an improved specimen evaluating a combination of 29 F1 paprika and Serrano pepper (C. annuum) hybrids along with 19 of their respective parents. We were also able to identify how productive certain crossing combinations were at expressing a significant amount of positive heterosis for different characteristics of interest. From our correlation analyses, we were able to identify that a significant association can exist between fruit weight and fruit diameter, as well as when other characteristics were evaluated. In all, our results were able to reveal how effective certain combinations of parent material are towards production of offspring with improved traits expressing appreciable fruit characteristics and elevated phytochemical concentrations. Finally, the quantitative measurements produced in our F2 molecular marker experiment found significant amounts of variation for both flavonoids (quercetin and luteolin) and AA expression. It was evident that incorporation of the necessary genes of interest present within fruit tissue across this F2 family for these different phytochemicals were passed from ‘Ca377’ (P1) to several of these offspring. Three candidate primers were eventually identified for their potential polymorphic expression. However, after statistically analyzing the results, only one primer was identified as expressing a significant association (although the value was still relatively low) of variability with respect to luteolin. We also identified a significant association between quercetin and luteolin, quercetin and total flavonoids (quercetin+luteolin), as well as, luteolin and total flavonoids (quercetin+luteolin) in fruit tissues of different pepper material. From our results, we were able to arguably conclude that an environmental component may serve a more essential role in activating the necessary physiological processes to produce specific secondary metabolites. Although our RAPD technique was fairly straightforward and useful, some may argue that a more reliable technique would have been better. Therefore, we postulate that success may be possible in the near future if a different molecular marker technique is used.

Magister Scientiae (Biodiversity and Conservation Biology) / South Africa is recognised worldwide for its rich diversity of plants, many of which have been used in ethno-medicine. However, the use of wetland plant species in ethno-medicine required further investigations. This research is aimed at investigating three wetland medicinal, plant species, Centella asiatica, Cyperus longus and Typha capensis based on their geographical, seasonal, mineral nutrient (Fe, Mn, Ca, Mg, K and Na) and secondary metabolite characteristics. Samples of each species were collected from Grabouw, Kelderhoff, Kenilworth, Pringle Bay, University of the Western Cape (UWC) and Worcester within the Western Cape Province of South Africa. Specimen and soil collections were carried out during autumn, spring, summer and winter of 2014. Both plant and soil samples were acid digested and mineral nutrient concentrations in the samples were analysed using an atomic absorption spectrometer (AAS). Secondary metabolites were determined using analytical TLC on normal phase Merck-Silva gel coated aluminium plates as well as by using HPLC separation from crude extracts of C. asiatica, C. longus and T. capensis using LC-MS hardware from Agilent. The elemental analysis of soil samples showed that Ca, K, Mg, Mn and Zn concentrations were predominantly low. Soil mineral concentrations increased progressively from inland (Worcester) towards the coastland in the south (Pringle Bay). Calcium and sodium concentrations, in particular, were higher in soil samples obtained from Grabouw (inland south) and decreased northward towards Worcester. Comparatively, plant mineral concentrations were generally higher than soil concentrations. The high concentration of some of these essential elements, in selected plants is an indication that these plant species could be a good source of essential elements. High concentrations of phytochemicals were found in Centella asiatica during winter, while Cyperus longus and Typha capensis exhibited high concentrations during autumn indicating variation in respect of season. Consequently, harvesting of the studied plants should be done at the season with a relatively high phytochemical concentration. Studies are needed to investigate the extent of pesticide or herbicide contamination in wetland plants to protect the health of users. The LC-MS analyses of the three study species showed that seasonal variation affects metabolite constituents and moreover that these metabolite constituents differ from one locality to another. The seasonal variation of the elements in the studied medicinal plants justified the importance of harvesting seasons in the optimal utilization of the studied plants for medicinal purpose. s, for C. asiatica, anti-bacterial treatments for C. longus and fertility enhancement and birth control for T. capensis.

La galanthamine est un alcaloïde isoquinoléique, utilisé dans le monde entier pour le traitement palliatif de la maladie d’Alzheimer en raison de son pouvoir inhibiteur de l’acétylcholinestérase. Cet alcaloïde est extrait à partir de bulbes d’Amaryllidaceae, Leucojum aestivum, Galanthus nivalis, et Narcissus sp. ou obtenu par synthèse chimique. La difficulté principale de cette dernière réside dans le respect de la configuration des centres d'asymétrie. La culture de tissus in vitro pourrait constituer une alternative intéressante pour obtenir ce composé à haute valeur ajoutée. Le premier objectif de ce projet, vise à améliorer l’accumulation de cet alcaloïde par les biais des biotechnologies. Le second objectif est de rechercher par criblage phytochimique (HPLC, LCMS, GCMS, et HPTLC-MS) de bulbes in vitro et in vivo d’Amaryllidaceae, de nouveaux alcaloïdes biologiquement actifs. Le troisième objectif porte sur l’étude de la voie de biosynthèse en vue de réaliser une synthèse biomimétique de la galanthamine. Nous avons établi des cultures in vitro de 3 espèces d’Amaryllidaceae. La variation des paramètres exogènes a conduit à une accumulation accrue d’alcaloïdes (0,02 à 0,2 % MS). Le criblage phytochimique a conduit à l’identification d’alcaloïdes nouveaux issus des cultures in vitro, n’existant pas in vivo, et présentant un puissant pouvoir inhibiteur de l’acétylcholinestérase (40 à 80 % Inh). L’ajout, de la 4’-Ométhyl-d3-norbelladine aux cultures in vitro a conduit à sa métabolisation en trois types d’alcaloïdes deutérés. Une stimulation de la synthèse et du relargage de la galanthamine native (0,15 % MS et 0,16 % Milieu) a été observée en présence du précurseur deutéré / Galanthamine is an Amaryllidaceae alkaloid used worldwide for the symptomatic treatment of Alzheimer’s disease because of his capacity to inhibit the acetylcholinesterase enzyme. There are two galanthamine sources for medical applications. One is the total synthesis, a complicated process because galanthamine has three asymmetric carbons, requiring stereochemically controlled synthesis. Galanthamine is also extracted from bulbs of some Amaryllidaceae such as Leucojum aestivum, Galanthus nivalis, and Narcissus sp.. The first aim of this work is to improve the accumulation of this alkaloid using biotechnologies. The second aim consists on the phytochemical screening (HPLC, LCMS, GCMS, et HPTLCMS) of in vivo and in vitro Amaryllidaceae bulbs, in order to identify new alkaloids with important pharmacological activities. Finally, the third aim concerns the study of the biosynthesis pathway in order to establish a biomimetic synthesis of galanthamine. Therefore, we established in vitro cultures of three Amaryllidaceae species. The variation of exogenousparameters led to the obtainment of high galanthamine accumulation (0.02 to 0.2 % DW). The phytochemical screening showed new alkaloids in extracts of in vitro cultures, which did not exist in in vivo extracts, and possessing high acetylcholinesterase activity (40 to 80 % Inh). The 4’-O-methyl-d3-norbelladine is incorporated into three different groups ofAmaryllidaceae alkaloids. The addition of the labelled precursor to shoot cultures stimulated the synthesis of native galanthamine (0.15 % DW and 0.16 % Culture medium)

Plus de 300 alcaloïdes d’Amaryllidaceae doués d’activités biologiques ont été isolés à partir des plantes appartenant à cette famille. De nos jours, seule la galanthamine, utilisée pour le traitement palliatif de la maladie d’Alzheimer, est commercialisée. L’accumulation de ces alcaloïdes dans les plantes est limitée. La culture in vitro est une méthode alternative intéressante pour l’obtention plus aisée de ces alcaloïdes à haute valeur ajoutée. Le premier objectif de ce travail vise à développer une méthode de purification efficace, simple et rapide des extraits de plantes préalablement à leur analyse en LCMS et GCMS. Le second objectif est d’étudier l’effet de plusieurs facteurs exogènes, ajoutés au milieu de culture de bulbilles de Leucojum aestivum et de sa variété Gravety Giant en bioréacteurs RITA®, sur les voies de biosynthèse de la galanthamine et de la lycorine. La variation des paramètres exogènes a permis une accumulation accrue en galanthamine et en lycorine (0,814 mg/g et 1,54 mg/g de matière sèche respectivement) dans les bulbilles. Le troisième objectif porte sur l’isolement et l’identification d’endophytes à partir de bulbes in vivo et in vitro de trois espèces d’Amaryllidaceae (L. aestivum, Narcissus pseudonarcissus et Galanthus elwesii). Des bactéries endophytes du genre Bacillus ont été identifiées. Un nouvel alcaloïde a été isolé à partir des cultures bactériennes / Over 300 Amaryllidaceae alkaloids possessing a wide range of biological activities have been isolated from plants belonging to this family. Galanthamine, used for the palliative treatment of Alzheimer’s disease, is the only one commercialized. The biodisponiblity of these alkaloids is low. In vitro culture offers an alternative yet interesting approach for the biotechnological production of these valuable alkaloids. The aim of this work was, first, to develop a fast, efficient and easy purification method of plant extracts prior to their phytochemical analysis both in LCMS and GCMS. Second, the combined effects of bioreactor RITA® culture and feeding with different exogenous factors on the biosynthetic pathway of both galanthamine and lycorine were studied. The experiments were conducted both with Leucojum aestivum and L. aestivum ‘Gravety Giant’ bulblets. The variation of several exogenous parameters resulted in a better accumulation of galanthamine and lycorine (0.814 mg/g and 1.54 mg/g dry weight respectively) in the bulblets. The third aim was to isolate and identify alkaloid producing endophytes from in vivo and in vitro bulbs of three Amaryllidaceae species (L. aestivum, Narcissus pseudonarcissus and Galanthus elwesii). Bacterial endophtes belonging to the Bacillus genus were identified. A new alkaloid was isolated from bacterial liquid cultures

L'objectif de cette thèse est d'évaluer les modifications du métabolisme secondaire des plantes contaminées aux éléments trace métalliques (ETM) et leurs conséquences sur les communautés bactériennes rhizosphériques associées incluant des bactéries présentant des phénotypes de MultiDrug Résistance (MDR). Nous nous sommes focalisés sur deux contextes de sols exposés aux métaux : la phytoremédiation de sites miniers au Vietnam et la reconversion de sols agricoles contaminés par la re-déposition atmosphérique d'activités métallurgiques en France. Nos résultats ont mis en évidence que la contamination par différents types de métaux (dont Cu et Pb principalement) a conduit à une altération de la production des métabolites secondaires des racines, tiges et feuilles de la plante hyperaccumulatrice Pteris vittata et que concernant les racines des tendances similaires dans les changements métaboliques ont pu être observés dans un autre type de contexte de pollution (Zn et Pb plus particulièrement). De même, les profils métaboliques des parties souterraines (racines et rhizomes) de Miscanthus x giganteus ont été modifiés par les concentrations en Pb, Cd et Zn des sols agricoles. Pour les deux plantes examinées des dérivés de l'acide chlorogénique ont été retrouvés en proportions augmentées dans les racines malgré des contextes de nature des sols et de pollutions métalliques très contrastés. Cependant, les dérivés de tanin catéchiques sont spécifiquement trouvés en proportions plus élevées dans les racines de P. vittata sous pression métallique. Ces polyphénols sont connus pour leur capacité à piéger les radicaux libres et leur pouvoir antioxydant et pourraient donc être impliqués dans l'adaptation de ces plantes au stress métallique en contribuant à limiter le stress oxydatif généré par les ETM. Au niveau des parties aériennes, nous n'avons étudié que le changement pour P. vittata et avons mis en évidence une proportion plus élevée de dérivés flavonoïdiques pour les plantes contaminées. Nos résultats de métagénomique nous permettent de conclure également sur un effet des ETM sur la diversité et la richesse spécifique des communautés bactériennes des sols étudiés : une forte contamination en Cu (10 fois la limite autorisée) a diminué la diversité et la richesse bactérienne, alors que pour des niveaux en ETM plus modérés incluant Cu, Pb et Zn, la diversité des communautés bactériennes rhizosphériques semble plus influencée par la plante ou la saison plutôt que par l'effet des ETM. Cet effet sur la composition bactérienne de la rhizosphère de P. vittata se traduit par un enrichissement de certains genres connus comme pathogènes opportunistes de l'homme, notamment Ralstonia, Acinetobacter, Burkholderia et Mycobacterium. En outre, le genre Cupriavidus, connu comme très résistant aux ETM est le seul genre spécifiquement associé à P. vittata qui ait été augmenté au sein de la communauté rhizosphérique pour les deux sites miniers étudiés par rapport aux sols rhizosphériques non pollués. Ce genre pourrait donc être impliqué dans le processus d'adaptation de cette plante au stress métallique. Quant aux communautés rhizosphériques de Miscanthus x giganteus, la sélection de Stenotrophomonas et Pseudomonas dans les sols agricoles contaminés a été observée. Dans le cadre de cette thèse nous avons également mis au point une méthode rapide pour tester l'impact de métabolites végétaux sur des souches pathogènes d'origine clinique et environnementale et également évaluer leur activité inhibitrice de pompes à efflux (IPE) de la famille des RND. Nos données ont ainsi permis de mettre en évidence des activités intéressantes et comparables à celle de l'inhibiteur de pompe à efflux PAßN pour des composés testés qui étaient extraits des racines de Fallopia x bohemica ou des dérivés de ces derniers. / The objective of this thesis is to evaluate the modification of plant secondary metabolism production contaminated with metallic trace elements (MTE) and its consequences on the associated rhizospheric bacterial communities including bacteria presenting MultiDrug Resistant (MDR) phenotypes. We have focused on two contexts of metals exposure: the phytoremediation of mining sites in Vietnam and the reconversion of agricultural soils contaminated by the atmospheric re-deposition of metallurgical activities in France. Our results highlighted that contamination by different types of metals (mainly Cu and Pb) has led to an alteration in the production of secondary metabolites in the roots, stems and leaves of the hyper-accumulating Pteris vittata and for roots, a similar trend in the metabolic changes could be observed in another type of pollution context (Zn and Pb more particularly). Similarly, the metabolic profiles of the underground parts (roots and rhizomes) of Miscanthus x giganteus were modified by the concentrations of Pb, Cd and Zn in agricultural soils. For the two plants examined chlorogenic acid derivatives have been found in increased proportions in the roots despite soil type and pollution context were highly contrasted. However, catechic tannin derivatives are specifically found in higher proportions in the roots of P. vittata under metal pressure. These polyphenols are known for their ability to scavenge free radicals and their antioxidant properties and thus could be involved in the adaptation of these plants to metallic stress by helping to limit the oxidative stress generated by MTE. At the level of the aerial parts, we studied only the change for P. vittata and evidenced higher proportions of flavonoid derivatives for contaminated plants. Our metagenomic results allow us to conclude also on the effect of MTE on the diversity and the specific richness of the bacterial communities of the studied soils: a high contamination of Cu (10 times the allowed limit) decreased dramatically bacterial richness and diversity, while for more moderate MTE levels including Cu Pb and Zn, the diversity of rhizosphere bacterial communities was more explained by plant or season effect rather than an effect of MTE. This effect on P.vittata rhizosphere bacterial composition is reflected by an enrichment in genera known as opportunistic human pathogens, including Ralstonia, Acinetobacter, Burkholderia and Mycobacterium. In addition, Cupriavidus, known as a highly resistant genus, is the only P. vittata specifically associated genus found in increased proportions at both mining sites compared to non-contaminated rhizosphere soils. This genus could then be involved in the adaptation process of this plant with metal stress. As for the rhizospheric communities of Miscanthus x giganteus, the selection of Stenotrophomonas and Pseudomonas in agricultural soils contaminated with MTE was observed. As a part of this thesis, we have also developed a rapid method for testing the impact of plant metabolites on pathogenic strains of clinical and environmental origin and their efflux pump inhibition (EPI) activity of RND family. Our data thus showed interesting and notable EPI activities comparable to that of the efflux pump inhibitor PAßN for tested compounds issued from Fallopia x bohemica roots or for their derivatives.

Ethanol extracts of “jenipapo” (Genipa americana Linnaeus), “umbu" (Spondia tuberosa Arruda), “siriguela” (Spondia purpurea Linnaeus) and “mangaba” (Hancornia speciosa Gomes) were prepared from separate pulp, seeds and peel; except mangaba which are used pulp and peel. The investigation of antioxidant capacity of the ethanol extracts were carried out by the methods of determining the content of ascorbic acid and total phenolics; scavenging 2, 2 -diphenyl-1-picrilhydrazyl and 2, 2’- azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical, antioxidant capacity of reduction of iron and copper and lipid peroxidation using a biomimetic membrane system, and measurement enzymatic of catalase and superoxide dismutase. It was also analyzed the acetylcholinesterase inhibitory activity, cytotoxic effect on corneal epithelial cells of sheep, as well as phytochemicals assays and identification of phenolic compounds and organic acids present in the extracts by UPLC - MS. The highest values of total phenolic content were obtained with peel and seed extracts and to ascorbic acid in the seed of siriguela, showing better antioxidant activities of seeds and peel extracts of siriguela and umbu. Lipid peroxidation assays indicated that genipap pulp is a promising antioxidant. Genipap pulp and siriguela seed ethanol extracts presented an acetylcholinesterase inhibition zone similar to that of the positive control, carbachol. The investigation of phenols and organic acid contents revealed the presence of quercetin (48,38 to 3,88 μg.g-1), quinic acid (43,28 to 41,88 μg.g-1) and citric acid (3,78 to 0,43 μg.g-1) in several extracts and chlorogenic acid with the highest amount found in siriguela seeds (356,93 μg.g-1). These data suggest new uses for these foods as potential antioxidant supplements for the food, pharmaceutical and cosmetic industries. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A partir das cascas, polpas e sementes do jenipapo (Genipa americana Linnaeus), umbu (Spondia tuberosa Arruda), siriguela (Spondia purpurea Linnaeus) e mangaba (Hancornia speciosa Gomes) foram preparados extratos etanólicos, com exceção da mangaba onde o extrato foi preparado utilizando casca e polpa. Os extratos foram submetidos à investigação da capacidade antioxidante através dos métodos de determinação do conteúdo de ácido ascórbico e fenóis totais, sequestro do radical 2,2-difenil-1-picril-hidrazil e 2,2´- azinobis (3-etilbenzotiazolina-6-ácido sulfônico), capacidade antioxidante de redução do ferro e cobre, lipoperoxidação utilizando um sistema de membranas biomimético e mensuração enzimática da catalase e superóxido dismutase. Também foi avaliada a atividade inibitória da enzima acetilcolinesterase, o efeito citotóxico em células epiteliais da córnea de ovelhas, além da realização de ensaios fitoquímicos e a identificação de compostos fenólicos e ácidos orgânicos presentes nos extratos. Os maiores teores de fenóis totais foram obtidos nos extratos das cascas e sementes e no referente ao ácido ascórbico na semente da siriguela, apresentando melhor atividade antioxidante os extratos das sementes e cascas da siriguela e do umbu. Porém, no ensaio de peroxidação lipídica, o extrato etanólico da polpa de jenipapo demonstrou ser um antioxidante promissor. Os extratos etanólicos da polpa do jenipapo e da semente da siriguela apresentaram uma zona de inibição da enzima acetilcolinesterase semelhantes ao controle positivo, carbacol. Na investigação dos compostos fenólicos e ácidos orgânicos por UPLC-MS verificou-se a presença nos extratos de quercetina (48,38 a 3,88 μg.g-1), ácido quínico (43,28 a 41,88 μg.g-1), ácido cítrico (3,78 a 0,43 μg.g-1) em vários extratos. E ácido clorogênico, na semente da siriguela (356,93 μg.g-1). Os resultados obtidos desses extratos sugerem novas formas de utilização desses alimentos como potenciais suplementos antioxidantes na indústria alimentícia, farmacêutica e cosmética.