Papers by Ewa Żymańczyk-Duda
Polish Journal of Chemistry, 2009
The application of nonionic detergents: Triton X100 and Tween 80, as permeabilizing agents was an... more The application of nonionic detergents: Triton X100 and Tween 80, as permeabilizing agents was an effective tool allowing to control the asymmetric hydrogen transfer in the biocatalyzed, enantioselective reduction of acetophenone to the desired optical isomer of 1-phenylethanol. Depending on the permeabilization procedure, the application of Geotrichum candidum, after the Triton X100 was applied, resulted in the formation of the R-enantiomer (79% of chemical yield and 72% of e.e), whereas bioreduction following the use of Tween 80 led to the S-form of 1-phenylethanol (51% of yield and 93% of e.e).
Journal of biotechnology & biomaterials, Mar 31, 2017
C hirality is a crucial feature in the world of living organisms. This is responsible for the spe... more C hirality is a crucial feature in the world of living organisms. This is responsible for the specific interactions between biologically active compounds in nature; therefore, it is also fundamental for designing the novel compounds. Among P-C compounds, structures are phosphonate derivatives such as amino phosphonates, keto phosphonates, hydroxy phosphonates. These are analogues of physiological compounds, so they are applied as moderators of activity of particular enzymes involved in natural compounds metabolic pathways. For such purposes, it is necessary to receive them as defined optical isomers. Chemical synthesis of such phosphonates is of low-effectiveness, also for the economic reasons, so biocatalytical approach appeared to be a good alternative. Good results were achieved for the kinetic resolutions of the racemic mixtures of amino-and hydroxy-phosphonates. This was performed via selective oxidation and employing following fungal genera: Penicillium, Beauveria, Cunninghamella, Verticillium, Cladosporium, Rhodotorula and Saccharomyces (as whole-cells biocatalysts). The same fungal mycelia were able to selectively reduce (thermodynamic process) prochiral keto phosphonates. The above mentioned experiments succeeded based on the laboratory scale and the most effective ones were selected for scaling-up process. This was the hardest part, because it required the modifications of the biotransformation procedures and the biocatalyst form. Experiments were performed with the use of batch and continuous reactors, and the fungal mycelia were immobilized with the use of polyurethane foams.
Current Organic Chemistry, 2012
This article discusses advantages and limitations of the biotransformations with enzymes and whol... more This article discusses advantages and limitations of the biotransformations with enzymes and whole-cell catalysts. It reviews biocatalytic synthesis of the chiral, organophosphorus compounds of different structures and characterizes their biological importance.
Polish Journal of Chemistry, 2007
Biotransformations of diethyl ester of 2-oxobutylphosphonate catalyzed by different kinds of yeas... more Biotransformations of diethyl ester of 2-oxobutylphosphonate catalyzed by different kinds of yeasts: Rhodotorula gracilis and baker yeasts allowed to obtain optically pure product - hydroxyphosphonate ofR - absolute configuration. Chemical yield of the reaction was depended on the microbial cells pretreatment and on the chemical additives, which are known to modify dehydrogenase activity [1].
Entomopathogenic fungi perform important functions in the ecosystem as natural antagonists of ins... more Entomopathogenic fungi perform important functions in the ecosystem as natural antagonists of insects, which can be used in agriculture. Interestingly, recent studies showed a significant promotion of tested plants growth in the presence of fungi. We hypothesize that some of various compounds produced by entomopathogenic fungi can positively affect plant development. To test this hypothesis, fungal extracts of entomopathogenic fungus Beauveria bassiana) were prepared at different conditions of temperature and pH. In addition to determination of the ammonium nitrogen content, the composition of extracts was analyzed by elemental ICP-OES. Then, their effect on the wheat germ growth was studied using various extract concentrations. After experiments, tested plants were measured, weighed, and the chlorophyll content was determined. Finally, the impact of extracts on the selected G+ and G- bacteria growth was examined to exclude the possibility of interference with soil microorganisms. T...
Autor do korespondencji: Mgr inż. Monika SerAfin, e-mail: [email protected] Wstęp Jedną ... more Autor do korespondencji: Mgr inż. Monika SerAfin, e-mail: [email protected] Wstęp Jedną ze znaczących innowacji w dziedzinie syntezy chemicznej było zastosowanie systemów biologicznych do prowadzenia reakcji chemicznych [1]. Wykorzystanie enzymów jako biokatalizatorów do otrzymywania optycznie czystych związków staje się powszechną metodą, szczególnie w przemyśle farmaceutycznym [2]. Uzyskiwanie chiralnych związków w postaci enancjomerów o zdefiniowanej konfiguracji, stosowanych, np. jako leki, jest coraz bardziej pożądane. Wynika to nie tylko ze skuteczności takich farmaceutyków, lecz również z coraz większej presji rynku ukierunkowanej na bezpieczeństwo stosowania związków chemicznych [1]. Biokataliza jest atrakcyjna dla chemików organików ze względu na możliwość wykorzystania naturalnych cech biokatalizatorów (regioczy stereoselektywności), a także na łatwość produkcji. Możliwość skrócenia procesu technologicznego wpływa pozytywnie na jego rentowność . Procesy bazujące n...
Microorganisms
Cyanobacteria are blue-green Gram-negative and photosynthetic bacteria which are seen as one of t... more Cyanobacteria are blue-green Gram-negative and photosynthetic bacteria which are seen as one of the most morphologically numerous groups of prokaryotes. Because of their ability to fix gaseous nitrogen and carbon dioxide to organic materials, they are known to play important roles in the universal nutrient cycle. Cyanobacteria has emerged as one of the promising resources to combat the issues of global warming, disease outbreaks, nutrition insecurity, energy crises as well as persistent daily human population increases. Cyanobacteria possess significant levels of macro and micronutrient substances which facilitate the versatile popularity to be utilized as human food and protein supplements in many countries such as Asia. Cyanobacteria has been employed as a complementary dietary constituent of feed for poultry and as vitamin and protein supplement in aquatic lives. They are effectively used to deal with numerous tasks in various fields of biotechnology, such as agricultural (includ...
Aspergillus niger (IAFB 2301) was employed for bioconversions of 2-phenylethanol as an immobilize... more Aspergillus niger (IAFB 2301) was employed for bioconversions of 2-phenylethanol as an immobilized or free mycelium and also as a spore suspension. Experiments were conducted on laboratory and half-preparative scale (bioreactor New Brunswick Scientific, BioFlo Model C32). Thus, A. niger applied as free mycelium, depending on the outcome, supported formation of the mixture of 4-hydroxyphenylacetic acid and hydroxytyrosol (final concentration of 13.8 mg/L and 3.7% efficiency) or 4-hydroxyphenylacetic acid, as single product (final concentration of 140 mg/L and 18% efficiency). In case of scaling experiments conducted with flow and batch reactors, accordingly, the following results were achieved: 1. mixture of antioxidants 4-hydroxyphenylacetic acid and hydroxytyrosol formed with final concentration of 76 mg/L and 10% efficiency (simplified flow system and immobilized mycelium); 2. (S)-1-phenylethane-1,2-diol synthesized with a final concentration of 447 mg/L and 65% (1.3 L batch react...
Microbial Cell Factories
Background Phosphonates derivatives are in the area of interests because of their unique chemical... more Background Phosphonates derivatives are in the area of interests because of their unique chemical-physical features. These compounds manifest variety of biological interactions within the sensitive living cells, including impact on particular enzymes activities. Biological “cause and effect” interactions are based upon the specific matching between the structures and/or compounds and this is usually the result of proper optical configurations of particular chiral moieties. Presented research is targeted to the phosphonates with the heteroatom incorporated in their side functionalities. Such molecules are described as possible substrates of bioconversion for the first time lately and this field is not fully explored. Results Presented research is targeted to the synthesis of pure hetero-phosphonates enantiomers. The catalytic activity of yeasts and moulds were tested towards two substrates: the thienyl and imidazole phosphonates to resolve their racemic mixtures. Biotransformations c...
Catalysts
Cyanobacteria constitute an interesting group of photosynthetic microorganisms due to their morph... more Cyanobacteria constitute an interesting group of photosynthetic microorganisms due to their morphological and genetic diversity that is related to their extremely long evolution process, which created the need for them to adapt to immensely heterogeneous environmental conditions. Cyanobacteria grow in salt and fresh waters as well as on the surface of soils and rocks. The diverse cell structure is characterized by the fact that they occur in many morphological forms, from small single cells through to larger ones as well as branches, threads, or spirals. Taking into account the presence of cyanobacteria in virtually all possible conditions and places on Earth, cyanobacteria represent an unexplored potential that is worth investigating. This review presents the possibilities of using algae in chosen areas of biotechnology: e.g., as biocatalysts or in industries such as the pharmaceutical industry. It covers the characteristics of secondary metabolites along with their division and th...
Chemistry - A European Journal, 2000
LiGaH 4 , in combination with the S,O-chelate 2-hydroxy-2'-mercapto-1,1'binaphthyl (MTBH 2), form... more LiGaH 4 , in combination with the S,O-chelate 2-hydroxy-2'-mercapto-1,1'binaphthyl (MTBH 2), forms an active catalyst for the asymmetric reduction of prochiral ketones, with catecholborane as the hydride source. Enantioface differentiation is on the basis of the steric requirements of the ketone substituents. Aryl/ n-alkyl ketones are reduced in 90 ± 93 % ee and RC(O)Me (e.g. R iPr, cycloC 6 H 11 , tBu) in 60 ± 72 % ee. Other borane sources and alternative catalyst structures based on indium do not form enantioselective catalysts.
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Papers by Ewa Żymańczyk-Duda