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    Wyświetlanie 1-11 z 11
    Tytuł:
    Chromatographic fractionation of betacyanins from flowers of Gomphrena globosa
    Autorzy:
    Szot, D.
    Starzak, K.
    Skopińska, A.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115427.pdf
    Data publikacji:
    2015
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betacyanins
    Gomphrena globosa
    plant pigments
    LC-MS
    betacyjaniny
    Gomfrena kulista
    barwniki roślinne
    Opis:
    In this study, a chromatographic fractionation of betacyanin pigments from extract of purple Gomphrena globosa petals was performed by preparative high performance liquid chromatography (prep-HPLC). The particular betacyanins in each collected fractions were tentatively identified by chromatography with optical amd mass spetrometric detection (LC-DAD-ESI-MS). Betacyanins are natural pigments, which are confirmed to have an antioxidant activity. It was reported that betacyanins can prevent civilization diseases, because of an ability of free radicals scavenging. Betacyanins are present in tissue of plants from Amaranthaceae family, e.g. in petals of Gomphrena globosa. Preparative separation of these particular pigments is difficult, because they are structurally very similar to each other and tend to coelute. However, in this study, fractions, containing a dominant amount of the principal pigments of Gomphrena globosa inflorescences, were obtained successfully. In the first fractions, two isomeric pigments assigned to gomphrenin I and isogomphrenin I were detected. The fractions of significant amounts of gomphrenin III and isogomphrenin III were obtained separately with sufficient purity. The presence of other, minor gomphrenin-type betacyanins were also confirmed as: gomphrenin II, cis-isomer of gomphrenin II and sinapoyl-gomphrenin I as well as their 15S-diastereomers. Moreover, in other fractions, various unknown pigments were detected.
    Źródło:
    Challenges of Modern Technology; 2015, 6, 2; 19-23
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Cu (II) Cations on 2-Decarboxy-betanin Stability in Aqueous-Organic Solutions
    Autorzy:
    Skopińska, A.
    Szot, D.
    Starzak, K.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115534.pdf
    Data publikacji:
    2015
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betacyanins
    2-decarboxy-betanin
    copper ions
    betalain stability
    Beta vulgaris L.
    betacyjaniny
    2-dekarboksy-betanina
    jony miedzi
    stabilność betalainy
    Opis:
    Several important factors, such us pH, exposure to light, oxygen or temperature affect significantly the betalain stability. In particular, the heavy metal ions exert negative effect on stability of betalain colorants and accelerate pigment decomposition. Trace amounts of metal ions may be present in the food products, as well as in food packaging, leading to undesirable colour changes or even discoloration of betalainic foodstuffs. Decarboxylated betalains, such as 2-decarboxy-betanin, generated, e.g. during betalain thermal treatment, may exhibit greater stability than parent pigments. Moreover, obtained derivatives retain attractive color, making them the promising material for study of pigment stability. An effect of Cu2+ cations as the most degradative metal ions on 2-decarboxy-betanin stability was investigated in ethanolic and methanolic solutions. The increase of the concentration of copper cations has a negative impact on stability of 2-decarboxy-betanin. The cations of Cu (II) in the presence of organic solvents induce the pigment degradation, while the increase of the concentration of organic solvents enhances the pigment decomposition. The main degradation products of the 2-decarboxy-betanin are compounds possessing absorption maxima at λmax ca. 430 nm. These studies allow obtaining the information needed for proper isolation and treatment of pigments, as well as proper storage of products containing betalains.
    Źródło:
    Challenges of Modern Technology; 2015, 6, 3; 24-29
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    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:
    Mass spectrometric detection of products of decarboxy-betanins UV-irradiation
    Autorzy:
    Starzak, K.
    Skopińska, A.
    Szot, D.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115619.pdf
    Data publikacji:
    2014
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    UV irradiation
    natural plant pigments
    betalains
    promieniowanie UV
    naturalne barwniki roślinne
    barwniki betalain
    Opis:
    Betalains are a group of natural plant pigments, responsible for red-violet colour of numerous flowers, fruits and roots. They commonly occur in order of Caryophyllales (Caryophyllales). Recent studies revealed great health promoting properties of these pigments, but their natural origin make them very labile under various physicochemical conditions. In the case of betanin degradation, many new, decarboxy-betanins are formed. Latest study showed that UV-irradiation had significant impact on betanin stability, however, no deeper studies were performed in this field. In order to know an impact of the process conditions on degradation of betanin and its decarboxylated derivatives, series of experiments with UV-photo-irradiation was performed in aqueous solutions as well as in various organic solvents at wide range of pH. The highest pigment stability was observed in aqueous solutions for betanin and 17-decarboxybetanin at pH 4.5–7, and for 2,17-didecarboxybetanin at low pH. In all investigated organic solutions, all of the studied compounds have been degraded. The LC-DAD-ESI-MS analysis identified new reaction products. The results showed that UV-photo-irradiation leads mainly to a formation of many new and various 14,15-dehydrobetanins.
    Źródło:
    Challenges of Modern Technology; 2014, 5, 3; 22-26
    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:
    Thermal degradation of 17-decarboxy-betanin monitored by LC-MS
    Autorzy:
    Szot, D.
    Starzak, K.
    Skopińska, A.
    Tuwalska, D.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115566.pdf
    Data publikacji:
    2014
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    17-decarboxy-betanin
    betacyanins
    thermal degradation
    17-dekarboksy-betanina
    betacyjaniny
    degradacja termiczna
    Opis:
    A thermal stability study on 17-decarboxy-betanin depending on physicochemical process conditions was conducted. 17-decarboxy-betanin is one of betacyanin, natural origin pigments applied in food and pharmaceutical industry instead of artificial colorants. There is a need for searching of new non-toxic natural food components and this is a reason of increasing interest of betacyanins. As most derivatives of betanin obtained by decarboxylation, 17-decarboxy-betanin tends to degrade in the presence of some factors such as increased temperature or other conditions of the reaction environment [1]. This subject was investigated in this study because the stability of the pigments is still a significant issue limiting their wide application. The degradation of 17-decarboxy-betanin during heating in selected solutions: water as well as aqueous solutions of ethanol 50% (v/v), methanol 50% (v/v) and acetonitrile 50% (v/v) at pH in the range 3-8 was tested. As UV-Vis spectra indicate, 17-decarboxy-betanin tends to degrade mostly at pH 3, notwithstanding a type of solution. The products of degradation were identified by LC-DAD-ESI-MS. As a result of incubation at 85°C in different solutions, various mono-, bi- and tridecarboxylated as well as dehydrogenated derivatives were obtained. The dominant product of 17-de-carboxy-betanin degradation is 2,15,17-tridecarboxy-2,3-dehydro-betanin.
    Źródło:
    Challenges of Modern Technology; 2014, 5, 3; 32-36
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Enzymatic oxidation of neobetanin monitored by liquid chromatography with mass spectrometric detection
    Autorzy:
    Starzak, K.
    Szot, D.
    Skopińska, A.
    Swiergosz, T.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115945.pdf
    Data publikacji:
    2016
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    neobetanin
    betalains
    betacyanins
    horseradish peroxidase
    oxidation
    enzymatic
    spectrophotometry
    mass spectrometry
    chromatography
    neobetanina
    betalainy
    betacyjaniny
    peroksydaza chrzanowa
    enzymatyczne utlenianie
    spektrofotometria
    spektrometria masowa
    chromatografia
    Opis:
    The aim of this study was monitoring of enzymatic oxidation of neobetanin, an interesting type of betalains which is a partially oxidized betacyanin. As it belongs to betalains, it is water soluble and non-toxic, but a presence of a few functional groups makes it very reactive. Oxidation reactions were performed using horseradish peroxidase followed by spectrophotometric and mass spectrometric detection (LC-DAD-ESI-MS/MS) of obtained products. Enzymatic oxidation of neobetanin leads to a formation of new decarboxy- and dehydro-derivatives. The main identified oxidation product is 2-decarboxy-2,3-dehydroneobetanin. Searching for all formed oxidation products is extremely important for elucidation of the betalains oxidation mechanism.
    Źródło:
    Challenges of Modern Technology; 2016, 7, 1; 29-31
    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
    Tytuł:
    The effect of ascorbic acid supplementation on betacyanin stability in purple pitaya (Hylocereus polyrhizus) juice
    Autorzy:
    Skopińska, A.
    Szot, D.
    Starzak, K.
    Mizrahi, Y.
    Wybraniec, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115881.pdf
    Data publikacji:
    2015
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    betalains
    betacyanins
    Hylocereus polyrhizus
    thermal treatment of natural pigments
    ascorbic acid
    betalainy
    betacyjaniny
    obróbka termiczna naturalnych pigmentów
    kwas askorbinowy
    Opis:
    Current studies on betalains are focused on searching of new plant sources of these pigments. In this light, purple pitaya (Hylocereus polyrhizus) is a valuable batalain-containing fruit. Betalains are known to be sensitive at elevated temperatures conditions. Nevertheless, addition of specific food stabilizers (EDTA, ascorbic acid, citric acid) as well as natural matrix compounds may exert stabilizing effect on maintenance of pigments. Therefore, in presented study, the stability of betalains in Hylocereus polyrhizus juices with protective addition of ascorbic acid at 85 ̊C was examined. Spectrophotometric analyses enable monitoring of reaction during heating of solutions. The hypsochromic shift of λmax to 460 nm is observed in more acidic media without ascorbic acid, suggesting the generation of new reaction products. These absorption bands in solutions with ascorbic acid are not detected, indicating on retaining of the basic structure of betalain chromophore. Generally, pigment retention is diminishing with prolonged heating and depends on pH-values of tested solutions. The addition of ascorbic acid significantly affects the betalain stability. After 60 min of heating, more than 60% of the initial pigment is retained at pH 3-4 in samples of purple pitaya with ascorbic acid. In summary, betacyanins in purple pitaya juice are shown to exhibit proper heat stability, when are stabilized with ascorbic acid. However, a protective effect of natural juice matrix and ascorbic acid is more significant at acidic pH.
    Źródło:
    Challenges of Modern Technology; 2015, 6, 4; 14-18
    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:
    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
      Wyświetlanie 1-11 z 11

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