Artifizielle Metalloenzyme und heterogenisierte Übergangsmetall-Komplexe mit Triphos-Liganden : Synthese, Kupplungsstrategien und katalytische Aktivität

This doctoral thesis deals with artificial metalloenzymes and heterogenized transition metal complexes with Triphos ligands.In the first part of this work the Triphos ligand was modified and different functional groups were introduced in the ligand backbone for later covalent anchoring. By this the Triphos alcohol ligand and the Triphos aldehyde ligand were accessible.In the second part of this thesis coupling strategies were developed on the basis of these two ligands. For the heterogenisation of transition metal complexes the Triphos alcohol ligand was covalently tethered onto benzoic acid functionalized polystyrene by Steglich esterification. Subsequent complexation reactions with ruthenium and rhodium precursors lead to heterogenized complexes. These complexes were tested successfully in different hydrogenation reactions. In addition, PHIP experiments were conducted with success with the heterogenized rhodium complexes.For the synthesis of artificial metalloenzymes the Triphos aldehyde ligand took center of stage in the investigations. First it was complexated with rhodium precursors and then it was covalently tethered by a hydrazone bond to the protein FhuA which was provided with a maleimid hydrazide linker in the first place. The obtained artificial metalloenzyme was tested in hydrogenation reaction as well in methanol as in water. In both reaction media it showed high activity and long stability. In addition, the first known PHIP experiments were conducted with an aritifical Metalloenzyme in methanol and water and were positive

Аналіз методів біометричної ідентифікації для захисту даних на комп'ютері

Суть технічної проблеми: розробка нового підходу до обробки зображення відбитка пальця з метою ідентифікації особистості та обмеження доступу до комп'ютерних ресурсів

Vegan Diet Is Associated With Favorable Effects on the Metabolic Performance of Intestinal Microbiota: A Cross-Sectional Multi-Omics Study

Background and Aim: Plant-based diets are associated with potential health benefits, but the contribution of gut microbiota remains to be clarified. We aimed to identify differences in key features of microbiome composition and function with relevance to metabolic health in individuals adhering to a vegan vs. omnivore diet. Methods: This cross-sectional study involved lean, healthy vegans (n = 62) and omnivore (n = 33) subjects. We assessed their glucose and lipid metabolism and employed an integrated multi-omics approach (16S rRNA sequencing, metabolomics profiling) to compare dietary intake, metabolic health, gut microbiome, and fecal, serum, and urine metabolomes. Results: The vegans had more favorable glucose and lipid homeostasis profiles than the omnivores. Long-term reported adherence to a vegan diet affected only 14.8% of all detected bacterial genera in fecal microbiome. However, significant differences in vegan and omnivore metabolomes were observed. In feces, 43.3% of all identified metabolites were significantly different between the vegans and omnivores, such as amino acid fermentation products p-cresol, scatole, indole, methional (lower in the vegans), and polysaccharide fermentation product short- and medium-chain fatty acids (SCFAs, MCFAs), and their derivatives (higher in the vegans). Vegan serum metabolome differed markedly from the omnivores (55.8% of all metabolites), especially in amino acid composition, such as low BCAAs, high SCFAs (formic-, acetic-, propionic-, butyric acids), and dimethylsulfone, the latter two being potential host microbiome co-metabolites. Using a machine-learning approach, we tested the discriminative power of each dataset. Best results were obtained for serum metabolome (accuracy rate 91.6%). Conclusion: While only small differences in the gut microbiota were found between the groups, their metabolic activity differed substantially. In particular, we observed a significantly different abundance of fermentation products associated with protein and carbohydrate intakes in the vegans. Vegans had significantly lower abundances of potentially harmful (such as p-cresol, lithocholic acid, BCAAs, aromatic compounds, etc.) and higher occurrence of potentially beneficial metabolites (SCFAs and their derivatives)