20.500.12556/RUL-170660 Vpliv topil na z lakazo katalizirano pretvorbo tirozol acetata Effect of solvents on laccase-catalyzed transformation of tyrosol acetate Biokatalitski procesi so primerni za razvoj trajnostne proizvodnje, saj sledijo načelom zelene kemije, kot so zmanjšanje odpadkov, energetska učinkovitost, nizka toksičnost, uporaba varnih topil, blagi in varni reakcijski pogoji ter uporaba katalizatorjev. Vendar pa vpeljavo biokatalitskih procesov v industrijo pogosto omejuje nizka topnost organskih substratov v vodi, zato je iskanje ustreznih nadomestnih topil izjemnega pomena za to področje. V magistrskem delu smo preučevali topila za oksidacijo tirozol acetata z lakazo za pridobivanje derivata magnolola, potencialnega zdravila za sladkorno bolezen. Preučevali smo vpliv različnih topil na topnost substrata in aktivnost encima ter optimizirali reakcijske pogoje za dosego čim višje konverzije in selektivnosti reakcije. Prvotno smo reakcijo izvedli v dvofaznem sistemu pufer/etil acetat, nato pa še v enofaznih sistemih z različnimi sotopili. Rezultati so pokazali, da sta najustreznejši topili acetatni pufer s propilen glikolom in acetatni pufer z acetonom, ki sta zagotavljala visoko encimsko aktivnost in dobro topnost substrata. Poleg tega smo pokazali, da topilo vpliva na selektivnost reakcije: v prisotnosti etil acetata, propilen glikola in acetona je med produkti prevladoval 1-,1′-ditirozol-8,8′-diacetat, medtem ko je pri dodatku oktanojske kisline nastalo več (7-okso-6,7-dihidrodibenzo[b,d]furan-2,9a(5aH)-diil)bis(etan-2,1-diil) diacetata. V sistemih s sotopilom smo zaznali večjo izgubo mase topnih produktov zaradi obarjanja stranskih produktov. Reakcijo v acetatnem pufru z acetonom smo izvedli tudi v mikropretočnem sistemu s segmentiranim tokom, kjer je prav tako kot v šaržnem sistemu med produkti prevladoval želeni produkt 1-,1′-ditirozol-8,8′-diacetat. Biocatalytic processes are suitable for the development of sustainable production, as they follow the principles of green chemistry, such as waste reduction, energy efficiency, low toxicity, the use of safe solvents, mild and safe reaction conditions, and the use of catalysts. However, the implementation of biocatalytic processes in industry is often limited by the low solubility of organic substrates in water, which makes the search for suitable alternative solvents extremely important in this field. In this master's thesis, we investigated solvents suitable for the oxidation of tyrosol acetate with laccase to produce a magnolol derivative, a potential drug for diabetes treatment. We studied the influence of different solvents on substrate solubility and enzyme activity, and we optimized the reaction conditions to achieve the highest possible conversion and selectivity of the reaction. Initially, the reaction was performed in a biphasic system (buffer/ethyl acetate), and later also in monophasic systems with various co-solvents. The results showed that the most suitable solvents were acetate buffer with propylene glycol and acetate buffer with acetone, as they provided high enzymatic activity and good substrate solubility. Additionally, we demonstrated that the solvent influences the selectivity of the reaction: in the presence of ethyl acetate, propylene glycol, and acetone, the predominant product was 1-,1′-dityrosol-8,8′-diacetate, while the addition of octanoic acid led to the formation of more (7-oxo-6,7-dihydrodibenzo[b,d]furan-2,9a(5aH)-diyl)bis(ethane-2,1-diyl) diacetate. In systems with co-solvents, we observed a greater loss of mass of soluble products due to the precipitation of side products. The reaction in acetate buffer with acetone was also performed in a microflow segmented flow system, where similarly to the batch system, 1-,1′-dityrosol-8,8′-diacetate was the predominant product. biotransformacija lakaza zelena topila mikropretočni sistemi biotransformation laccase green solvents microflow systems true false false Slovenski jezik Angleški jezik Magistrsko delo/naloga 2025-07-11 14:50:01 2025-07-11 14:50:15 2025-07-31 08:57:27 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 24282 244391427 Fabjan_Larisa_-_Vpliv_topil_na_z_lakazo_katalizirano_pretvorbo_tirozol_acetata.pdf Fabjan_Larisa_-_Vpliv_topil_na_z_lakazo_katalizirano_pretvorbo_tirozol_acetata.pdf 1 D1523EFF0B5A4A84B65CACB53331D304 060972a2ff854588af15a666b09bf8fcc42502432e9a2bc9c46b62f0cfabf102 ac687608-5e53-11f0-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=212702 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0