Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Szot, D." wg kryterium: Autor

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-7 z 7
    Tytuł:
    Profiles of products generated during betacyanins reduction by 2-methylpyridine borane
    Autorzy:
    Szot, D.
    Starzak, K.
    Skopińska, A.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115550.pdf
    Data publikacji:
    2015
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betanina
    neobetanina
    betacyjaniny
    redukcja
    2-2-metylopirydyna boranu
    LC-MS
    betanin
    neobetanin
    betacyanins
    reduction
    2-methylpyridine borane
    Opis:
    Betanin and neobetanin (14,15-dehydrogenated betanin), natural betacyanin pigments were subjected to a gentle reduction by 2-methylpyridine borane. During each reduction reaction, the visible spectra were collected. The results were tentatively confirmed by LC-DAD-ESI-MS. In comparison to a previous study with sodium borohydride, various types of products were obtained. Depending on pH, one or two double bonds are reduced. Interestingly, a preliminary decarboxylation of the pigments is also noticed. Betacyanins are plant red-violet pigments applied as colorants in food and pharmaceutical industry which are proven to have an antioxidant activity. They are confirmed to be beneficial for human health as free radical scavengers. Therefore, betacyanins can prevent from many diseases which would be induced by an excessive accumulation of free radicals in the human body. There are more and more reports of their pro-health properties. However, the mechanism of betacyanins oxidation remains not completely elucidated. It is postulated that the rearrangement in the chromophoric system is a significant part of this mechanism. The products obtained as a result of reduction of betanin and neobetanin can be useful in oxidation investigations. Betacyanins with partially destroyed chromophoric system by reduction of the double bonds would by perfect models for further studies on their oxidation.
    Źródło:
    Challenges of Modern Technology; 2015, 6, 4; 19-22
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Reactions of decarboxylated betanins under influence of halogen light
    Autorzy:
    Skopinska, A.
    Szot, D.
    Starzak, K.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115710.pdf
    Data publikacji:
    2014
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betanin
    decarboxylated betacyanins
    photolability
    mass spectrometry
    betanina
    dekarboksylacja betacyjaniny
    spektrometria masowa
    Opis:
    Betalains as natural plant pigments are very sensitive to several factors, including light, therefore, studies on stability of their derivatives which retain their attractive color, are crucial for their potential application in pharmaceutical, food or cosmetic industries. An effect of irradiation by halogen light on reactivity of main decarboxylated derivatives of betacyanins (2-decarboxy-betanin, 17-decarboxy-betanin and 2,17-decarboxy-betanin) was investigated in aqueous and organic-aqueous solutions: 50% (v/v) acetonitrile, 50% (v/v) methanol and 50% (v/v) ethanol, at pH range 3-8. The double decarboxylation of betanin (at C-2 and C-17 position of carbon) significantly increases the stability of this pigment in the acidic media. As a result of pigments reactions induced by light, some betacyanin derivatives with different decarboxylation and dehydrogenation levels were identified by chromatography with tandem mass spectrometry (LC-MS/MS) and diode array detection (LC-DAD).
    Źródło:
    Challenges of Modern Technology; 2014, 5, 3; 37-43
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spiral-coil countercurrent chromatographic separation of betanin and betanidin ethyl-esters monitored by continuous ESI-MS/MS injection and LC-ESI-MS/MS
    Autorzy:
    Tuwalska, D.
    Szot, D.
    Wybraniec, S.
    Winterhalter, P.
    Jerz, G.
    Powiązania:
    https://bibliotekanauki.pl/articles/115897.pdf
    Data publikacji:
    2013
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    spiral-coil countercurrent chromatography (spCCC)
    betacyanin ethyl-esters
    betalains
    betacyanins
    betanin
    betanidin
    Opis:
    Betalains present in Beta vulgaris L. (Chenopodiaceae) have a high potential as natural pigments for food applications. They have been used as a substitute of synthetic dyes in processing of gelatine, strawberry yogurts, ice creams, fruits cocktails, candies and biscuits. The stability of betalains is strongly influenced by numerous factors – sugar content, and impact of light, oxygen, water activity, pH and temperature. A mixture of betacyanin mono-, di- and tri-ethyl-esters was separated by a large-volume spiral-coil countercurrent chromatography (spCCC) prototype which yielded fractions continuously off-line injected to an ESI-MS/MS device. This method yielded a reconstituted pigment profile and finally enabled the MS-target-guided isolation procedure for the whole spCCC-experiment. The individual fractions were analyzed by LC/ESI-MS/MS. Betanin and betanidin mono-, di- and tri-ethyl-esters as well as other decarboxylated derivatives were detected in the chromatograms. The ethyl-esters of betanin were only partially fractionated, but clearly fractionated from the ethyl-esters of betanidin which will be of great value for biological evaluations.
    Źródło:
    Challenges of Modern Technology; 2013, 4, 4; 21-25
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Separation of betalains by gradient high-speed counter-current chromatography
    Autorzy:
    Spórna-Kucab, A.
    Udziela, D.
    Sobocińska, M.
    Szot, D.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115813.pdf
    Data publikacji:
    2016
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betanin
    betalains
    betacyanins
    high-speed counter-current chromatography
    Beta vulgaris L.
    betanina
    betalainy
    betacyjaniny
    HSCCC
    Opis:
    A study on separation of betalain mixture obtained from red beet juice (Beta vulgaris L.) by analytical high-speed counter-current chromatography (HSCCC) was performed. The extract was obtained by thermal treatment of acidified red beet juice for 30 min in 85 °C. The pigment mixture consisted of betanin/isobetanin as well as their decarboxy- and dehydro-derivatives. The HSCCC process was accomplished in the ‘tail to head’ mode with two polar solvent systems containing salt: BuOH-EtOH-NaClsolution-H2OH3PO4 (1300:700-1000:1300:700:2.5-5.5 (system I), 1300:200-400:1300:700:2.5-4.5 (system II); v/v/v/v/v). The retention of the stationary phase was 73% (system I) and 79% (system II). The mobile phase was pumped at 2 ml/min flow rate. HPLC-DAD-ESI-MS analyses were performed in reversed phase mode for the obtained HSCCC fractions and crude extract. The solvent systems enabled separation of betanin and decarboxy-betanins (system I and II) as well as neobetanin (system II). Additionally, some pure fractions of 17-decarboxy-betanin and 2,17-bidecarboxy-betanin were obtained in system II.
    Źródło:
    Challenges of Modern Technology; 2016, 7, 1; 23-28
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Semi-synthesis of red beet betacyanin ethyl-esters by esterification
    Autorzy:
    Tuwalska, D.
    Starzak, K.
    Szot, D.
    Wybraniec, S.
    Winterhalter, P.
    Jerz, G.
    Powiązania:
    https://bibliotekanauki.pl/articles/115735.pdf
    Data publikacji:
    2014
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betacyanin ethyl-esters
    betalains
    betacyanins
    betanin
    betanidin
    esterification
    estry etylowe
    betalainy
    betacyjaniny
    betanina
    betanidyna
    estryfikacja
    Opis:
    Red beet pigments recovered from Beta vulgaris L. (Chenopodiaceae), mainly consist of purple betacyanins, such as 15R/15S-betanin. Currently,this pigment class is intensively investigated in respect of stability in food systems. Quite popular is the use of red beet extracts in dairy products such as yoghurts, and ice-creams. So far, there are no issues of toxicity using these natural pigments in food – so they seem to be a very good alternative to replace synthetic dyes which had been frequently discussed for negative side-effects to human health. Betacyanins, the glycosidation products of betanidin are very polar and therefore water soluble pigments, which are biosynthetically derived from condensation of cyclo-DOPA and betalamic acid. The significant polarity of betacyanins requires the use of ion-pair reagents such as trifluoro-acetic acid (TFA) or other homologue fluorinated additives under standard separation conditions on larger scale in spiral coil countercurrent chromatography (spCCC). In our synthetic experiment, the polarity of the natural betacyanins was reduced. This omitted the use of toxic per-fluoro ion-pair reagents. The three carboxylic groups of the betanin pigment backbone were the target functional groups of the derivatisation. In semi-synthesis, fortified red beet pigment extract was esterified with water-free ethanolic hydrogen chloride solution. The reaction was carried out at ambient temperature (7 days) to yield a mixture of betacyanin mono-, di- and tri-ethyl-esters, and their epimeric forms, as well as the respective betanidin-ethyl-esters. The time course of the reaction mixture was monitored by analytical C18-HPLC with ESI-DAD-MS/MS detection. The detected molecular weights of the pigments confirmed the presence of expected products. To the best of our knowledge, the presence of betalains containing ethyl-ester groups in biological samples have not been studied before.
    Źródło:
    Challenges of Modern Technology; 2014, 5, 3; 27-31
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The effect of citric acid on stabilization of betanin solutions
    Autorzy:
    Skopińska, A.
    Szot, D.
    Tuwalska, D.
    Starzak, K.
    Osiadło, M.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115716.pdf
    Data publikacji:
    2014
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betanin
    betacyanins
    citric acid
    Beta vulgaris L.
    betanina
    betacyjaniny
    kwas cytrynowy
    Opis:
    Elevated temperature is known to be the most crucial factor influencing betanin integrity during food processing and storage. Nevertheless, certain chelating agents or antioxidants, such as acetic acid, may act as stabilizers. Therefore, the effect of citric acid on the stability of betanin – basic betacyanin – was investigated during the heating experiments in water as well as 50% and 95% (v/v) aqueous-organic solutions of methanol, ethanol and acetonitrile. The presence of citric acid in tested solutions affects betanin stability, especially in the 95 % solutions, in which the stabilizing effect of this compound is significantly higher than in aqueous solutions. However, some decrease of retention in 50% methanol was also observed. The main products of betanin thermal degradation in aqueous and aqueous-organic solutions were compounds characterized by absorption bands around the wavelength at 420 nm.
    Źródło:
    Challenges of Modern Technology; 2014, 5, 2; 19-24
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Research on solvent systems with tetra-n-butylammonium bromide for counter-current chromatography of betalains
    Autorzy:
    Spórna-Kucab, A.
    Wysoczańska, J.
    Bartel, A.
    Świergosz, T.
    Szot, D.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115657.pdf
    Data publikacji:
    2016
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betanin
    betalains
    tetra-n-butylammonium bromide
    high-speed counter-current chromatography
    Beta vulgaris L.
    betanina
    betalainy
    bromek tetra-n-butyloamoniowy
    HSCCC
    Opis:
    In this study, new two-phase solvent systems for counter-current chromatography (CCC) consisting of n-butanol and water as well as various amounts of acetic acid, acetonitrile, ethanol, acetone or ethyl acetate were tested. Additionally, tetra-n-butylammonium bromide (TBAB) was introduced into the system in the form of aqueous solutions or phosphate-citrate buffer (pH 6.7) in order to form ion-pairs with betalains. The selection of buffer pH was based on their ability to create ion pairs by tetraalkylammonium salts, with selected betalains under these conditions. In this study, it is shown that the settling time of two phases is longer with the increase of acetic acid/acetonitrile/ethanol/acetone/ethyl acetate. For selected solvent systems with high amounts of acetonitrile, ethanol and acetone two phases were not observed. The systems with acetone have the largest increase of settling time. Ethyl acetate systems were characterized by a slow settling time increase. In systems containing additionally 2% aqueous TBAB, smaller changes in settling time than in similar systems without TBAB were observed. Addition of TBAB in the buffer resulted in a prolongation of settling time. Solvent systems in which the separation between the aqueous and organic phases was visually best, were selected from among all the tested systems and the betalain partition coefficients were measured by LC-DAD-ESI-MS. The best results were observed for systems: n-butanol-water-acetic acid (2:2.5:0.75, v/v/v), n-butanol-water-acetic acid (2:2.5:1, v/v/v) and n-butanol-TBAB in water-acetonitrile (2:2.5:0.5, v/v/v).
    Źródło:
    Challenges of Modern Technology; 2016, 7, 1; 12-16
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-7 z 7

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies