Práce bude zaměřena na studium bakteriální degradace MCPP a BAM a na hledání vhodných bakteriálních kmenů.

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Lumnitzera littorea and Lumnitzera racemosa are mangrove species distributed widely along the Indonesian coasts. Besides their ecological importance, both are of interest owing to their wealth of natural products, some of which constitute potential sources for medicinal applications. We aimed to discover and characterize new anti-infective compounds, based on population-level sampling of both species from across the Indonesian Archipelago. Root metabolites were investigated by TLC, hyphenated LC-MS/MS and isolation, the internal transcribed spacer (ITS) region of rDNA was used for genetic characterization. Phytochemical characterization of both species revealed an unusual diversity in sulfated constituents with 3,3’,4’-tri-O-methyl-ellagic acid 4-sulfate representing the major compound in most samples. None of these compounds was previously reported for mangroves. Chemophenetic comparison of L. racemosa populations from different localities provided evolutionary information, as supported by molecular phylogenetic evidence. Samples of both species from particular locations exhibited anti-bacterial potential (Southern Nias Island and East Java against Gram-negative bacteria, Halmahera and Ternate Island against Gram-positive bacteria). In conclusion, Lumnitzera roots from natural mangrove stands represent a promising source for sulfated ellagic acid derivatives and further sulfur containing plant metabolites with potential human health benefits.

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Consumption of cocoa and dark chocolate products has been associated with positive health outcomes including reduced onset of cardiovascular disease, inflammation, diabetes, obesity, and platelet disorders. Cocoa polyphenols, putatively responsible for these beneficial activities, are highly impacted by cocoa variety, agronomic effects and processing history. However, the difference in polyphenol concentration and composition between cocoa products originating from different hybrid clones (selected for high yield) or from different fermentation conditions is not fully understood. Detailed polyphenol characterization including determination of total polyphenol and total procyanidin concentrations, and qualitative and quantitative analysis of (mean) degree of polymerization was conducted. Significant differences in total polyphenol and procyanidin concentrations were observed between five genetic clones grown by the USDA-ARS Cocoa Germplasm Repository located in Mayagüez, Puerto Rico. To facilitate cocoa fermentation research in laboratories distant from cocoa harvesting sites, a laboratory-scale cocoa fermentation model system was developed in this study. This model system used dried, unfermented, cocoa beans and simulated pulp medium as the starting material. The model system supported growth of the essential succession of cocoa fermenting microorganisms and generated similar chemical changes to those observed in on-farm cocoa fermentation. Using this model system, the impact of inoculation with proprietary yeast strains Saccharomyces cerevisiae Lev F and Saccharomyces cerevisiae Lev B on cocoa polyphenol concentration and composition was evaluated. Inoculation with both yeast strains resulted in increased fermentation rate and Lev B inoculation resulted in higher total polyphenol and procyandin contents at the end of fermentation. Overall, the present work addressed the influence of cocoa variety selection and fermentation process conditions on the composition and concentration of polyphenols. These findings will contribute to continued efforts to develop cocoa products with optimized bioactivity and maximum disease preventative effects. / PHD / Annual worldwide cocoa production exceeds four million tons and the cocoa market impacts not only cocoa growing regions, but also countries producing cocoa products. Consumption of cocoa and dark chocolate products has been associated with positive health outcomes including reduced onset of cardiovascular disease, inflammation, diabetes, obesity, and platelet disorders. Cocoa polyphenols, compounds increasingly associated with health benefits, are highly impacted by the variety and processing history of cocoa. However, the extent to which cocoa genetic variety and processing conditions impact polyphenol concentration and composition is not fully understood. Polyphenol characterization was conducted for five genetic varieties sourced from the USDA cocoa germplasm repository located in Mayagüez, Puerto Rico and it was found that genetic variance could contribute to differences in polyphenol concentration. The main focus in this thesis was to develop laboratory cocoa fermentation model system to facilitate cocoa research in laboratories distant from the cocoa growing region. This model system used dried, unfermented cocoa beans and simulated pulp medium as the starting material. The model system was effective in that it supported growth of the essential succession of coca fermenting microorganisms and generated similar chemical changes to those observed in on-farm cocoa fermentation. This model system could be further applied to test the impact of fermentation conditions on cocoa bean quality. The potential for using yeast starter cultures to improve control and consistency of cocoa fermentation was evaluated using the model fermentation system. Yeast inoculation improved fermentation rate, and polyphenol concentration in fermented beans was higher when cocoa fermentation was inoculated with the yeast strain Saccharomyces cerevisiae Lev B. Overall, the present work addressed the influence of cocoa variety selection and fermentation process conditions on the composition and concentration of polyphenols. These findings will contribute to continued efforts to develop cocoa products optimized for maximum health benefits.

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Le travail présenté dans cette thèse porte sur l’isolement de métabolites secondaires de trois invertébrés marins, ainsi que sur la synthèse de molécules hybrides, notamment à visée antifouling et inhibiteurs de kinases, inspirées des motifs naturels issus des familles dispacamides et 3-alkylpyridines. Les techniques spectroscopiques et les transformations chimiques ont été largement utilisées pour les déterminations structurales. Les nouveaux composés ont été évalués biologiquement.Le travail d’isolement sur le corail mou Sinularia vanderlandi a permis de mettre en évidence trois nouveaux composés de la famille de diterpènes norcembranoïdes, dont les configurations relatives ont été déterminées. Un lien chimique a également été établi entre les nouveaux composés isolés ainsi que ceux de la même famille décrits dans la litérature.Neuf nouvelles molécules ont été obtenues de l’éponge Pipestela candelabra, quatre phopholipides et cinq composés de la famille du jaspamide, les pipestelides A-C ainsi que les 5-hydropéroxy-jasplakinolides Ca et Cb. Des travaux d’hémisynthèse ont été réalisés à partir du jaspamide pour confirmer les structures des dérivés hydropéroxydés. Cette thèse contient également une étude partielle de l’éponge Stylissa carteri qui a mis a jour deux nouvelles benzosceptrines.Les travaux de synthèses ont eu pour but d’établir les voies d’accès à des dérivés l’obtention dispacamide / 3-alkylpyridine. Trois dérivés ont ainsi été synthétisés et les évaluations biologiques sont en cours, notamment pour les activités antifouling. Des aspects structuraux de ce type de dérivés ont été abordés par la synthèse d’autres dérivés. / The work described in this thesis deals with the isolation of new metabolites from marine invertebrates in one hand, and with the synthesis of antifouling and kinase inhibitors hybrid molecules inspired from dispacamide and 3-alkylpyridine scaffolds. Spectroscopic methods and chemical modifications were used for structural determination. The new compounds were biologically evaluated.Three new compounds of the norcembranoid diterpenes were isolated from the Soft Coral Sinularia vanderlandi. The relative configurations of these metabolites were determined and a chemical link was established between these diterpenes.The investigation of the marine Sponge Pipestela candelabra has conducted to the isolation of nine new metabolites, four phospholipids and five new jaspamide congeners including pipestelides A-C and 5-hydroperoxy-jasplakinolides Ca et Cb. Hemisynthesis were conducted from the jaspamide, together with spectroscopic analysis to confirm the structures of the peroxidated compounds.Two new derivatives of benzosceptrine were isolated from a partial study of the marine Sponge Stylissa carteri.The synthesis part of this work described the access to dispacamide / 3-alkylpyridine derivatives. Three hybrids were synthetized and biological evaluation are in progress, particularly for antifouling activities. Structural aspects were also studied by the synthesis of other derivatives

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