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5-hydroxymethylfurfural (HMF) is produced upon dehydration of C6 sugars in biorefineries. As the product, it remains either in aqueous solutions, or is in situ extracted to an organic medium (biphasic system). For the subsequent oxidation of HMF to 2,5-furandicarboxylic acid (FDCA), ‘media-agnostic’ catalysts that can be efficiently used in different conditions, from aqueous to biphasic, and to organic (microaqueous) media, are of interest. Here, the concept of a one-pot biocatalytic cascade for production of FDCA from HMF was reported, using galactose oxidase (GalOx) for the formation of 2,5-diformylfuran (DFF), followed by the lipase-mediated peracid oxidation of DFF to FDCA. GalOx maintained its catalytic activity upon exposure to a range of organic solvents with only 1 % (v/v) of water. The oxidation of HMF to 2,5-diformylfuran (DFF) was successfully established in ethyl acetate-based biphasic or microaqueous systems. To validate the concept, the reaction was conducted at 5 % (v/v) water, and integrated in a cascade where DFF was subsequently oxidized to FDCA in a reaction catalyzed by Candida antarctica lipase B. © 2022 The Authors. ChemSusChem published by Wiley-VCH GmbH.

Tato bakalářská práce se v teoretické části zabývá technologií výroby medoviny, jejím složením a fyzikálně chemickými vlastnostmi prolinu a 5-hydroxymethylfurfuralu. V experimentální části byl spektrofotometrickou technikou stanoven obsah prolinu a technikou kapalinové chromatografie v systému reverzních fází 5-hydroxymethylfurfural. Dále byl destilačně stanoven obsah alkoholu. Tyto parametry byly stanoveny celkem u třinácti vzorků medovin, sedm vzorků bylo získáno od včelařů a šest vzorků bylo zakoupeno v obchodních sítích., This thesis deals with the analysis of selected compounds in meads. In the teoretical part deals with technology of production of mead, its composition and physicochemical properties of proline and 5-hydroxymethylfurfural. Experimental part is focused on the determination of content of proline by spectrophotometric method and content of 5-hydroxymethylfurfural by RP- HPLC method with UV detection. Alcohol content was determined by distillation. These parameters were determined in thirteen samples of mead, seven samples were obtained from beekeepers and six were bought from the markets., Katedra analytické chemie, Studentka přednesla bakalářskou práci a zodpověděla otázky komise.