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1
Content available Research on stability of gomphrenin pigments influenced by Cu2+ ions
Szmyr N., Wybraniec S.
Challenges of Modern Technology
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2017
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Vol. 8, no. 1
13--18
EN
This paper concerns the results of dehydrogenation of gomphrenin pigments isolated from the purple flowers of Gomphrena globosa L. depending on pH and Cu2+ activity. Betalains are the plant dyes divided into red-violet betacyanins and yellow-orange betaxanthins. These compounds show prohealth properties proven by numerous studies [1]. Isolation of gomphrenins from the plant material was performed in the following stages: preparative extraction, filtration on a silica layer, preliminary purification and concentration on a bed of strong anion exchanger, preparative chromatographic fractionation and sample liofilization. The dehydrogenation studies of gomphrenin I and II were carried out in aqueous solutions (pH 3, 5 and 7) catalyzed by Cu2+ ions addition. The resulting product mixtures of dehydrogenated and decarboxylated gomphrenin derivatives were monitored by high-performance liquid chromatography with diode-array and mass spectrometric detection (LC-DAD-ESI-MS). Based on the results, it can be stated that decarboxylated and dehydrogenated gomphrenin II derivatives are more stable than gomphrenin I derivatives, presumably due to acylation of the glucose moiety. The highest levels of gomphrenin I derivatives were observed at pH 7, however, they were mainly monodecarboxylated ones. At pH 3, significant fraction was represented by tridecarboxylated and dehydrogenated derivatives. The lowest yield of the degradation products was indicated at pH 5.
2
Content available Research on dehydrogenation of gomphrenin in heated ammonia solutions of organic solvents
Szmyr N., Wybraniec S.
Challenges of Modern Technology
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2017
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Vol. 8, no. 1
8--12
EN
In this report, the influence of ammonia on dehydrogenation of gomphrenin pigment, isolated from purple inflorescences of Gomphrena globosa L., in selected organic solvents (methanol, ethanol, acetone and acetonitrile) at 40°C is presented. Betacyanins are water-soluble, vacuolar plant pigments. Due to their numerous pro-health properties, they can be applied in the pharmaceutical industry and as food colorants. However, as most of natural products, they are less stable than synthetic dyes, therefore, further studies need to be carried out on their stability, but also on determination of their degradation products as well as degradation mechanisms. For the experiments of the ammonia treatment, prolonged isolation of gomphrenin from the plant material including extraction, preliminary purification, preparative HPLC fractionation, concentration and liofilization were performed. The tested pigment dissolved in organic solvents was treated by ammonia and the samples for analysis were taken during and after reaction. For identification of obtained derivatives of gomphrenin, high-performance liquid chromatography with diode-array and mass spectrometric detection (LC-DAD-ESI-MS) was performed. As a result of heat processing, the mixture of decarboxylated and dehydrogenated gomphrenin derivatives was detected. Based on the experimental results, it can be stated that gomphrenin is characterized by the greatest stability in methanolic solutions while it is the most labile in the acetonitrilic ones.
3
Content available remote Przeciwprądowa chromatografia cieczowa w rozdzielaniu betalain
Spórna-Kucab A., Wybraniec S.
Przemysł Chemiczny
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2016
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T. 95, nr 10
1904--1906
PL
Dokonano przeglądu literaturowego zastosowań przeciwprądowej chromatografii cieczowej w rozdzielaniu betalain (barwniki naturalne). Dodatkowo zwrócono uwagę na cenne właściwości prozdrowotne betalain i innych związków naturalnych.
EN
Areview, with 36 refs. Some therapeutic properties of betalains were also taken into consideration.
4
Content available Separation of betalains by gradient high-speed counter-current chromatography
Spórna-Kucab A., Udziela D., Sobocińska M., Szot D., Wybraniec S.
Challenges of Modern Technology
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2016
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Vol. 7, no. 1
23--28
EN
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.
5
Content available Research on solvent systems with tetra-n-butylammonium bromide for counter-current chromatography of betalains
Spórna-Kucab A., Wysoczańska J., Bartel A., Świergosz T., Szot D., Wybraniec S.
Challenges of Modern Technology
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2016
|
Vol. 7, no. 1
12--16
EN
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).
6
Content available Enzymatic oxidation of neobetanin monitored by liquid chromatography with mass spectrometric detection
Starzak K., Szot D., Skopińska A., Swiergosz T., Wybraniec S.
Challenges of Modern Technology
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2016
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Vol. 7, no. 1
29--31
EN
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.
7
Content available The effect of ascorbic acid supplementation on betacyanin stability in purple pitaya (Hylocereus polyrhizus) juice
Skopińska A., Szot D., Starzak K., Mizrahi Y., Wybraniec S.
Challenges of Modern Technology
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2015
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Vol. 6, no. 4
14--18
EN
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.
8
Content available Semi-synthesis of red beet betacyanin ethyl-esters by esterification
Tuwalska D., Starzak K., Szot D., Wybraniec S., Winterhalter P., Jerz G.
Challenges of Modern Technology
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2014
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Vol. 5, no. 3
27--31
EN
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.
9
Content available Wpływ warunków ogrzewania roztworów koncentratu soku z buraka ćwikłowego na parametry barwy i zawartość barwników betalainowych
Gościnna K., Walkowiak-Tomczak D., Czapski J.
Aparatura Badawcza i Dydaktyczna
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2014
|
T. 19, nr 2
183-189
PL
Celem pracy było określenie wpływu ogrzewania roztworów koncentratu soku z buraka ćwikłowego rozcieńczonego do zawartości ekstraktu 14%, na zmiany parametrów barwy i barwników betalainowych. Zmiany te badano w zależności od pH roztworu, czasu i temperatury ogrzewania. Badania przeprowadzono z zastosowaniem metody płaszczyzn odpowiedzi wykorzystując układ doświadczalny Box-Behnkena. W czasie ogrzewania następowała degradacja fioletowych barwników betalainowych, tym większa, im dłuższy był czas i temperatura ogrzewania. Na zawartość żółtych barwników betalainowych największy wpływ miało pH. Największą stabilność barwników betalainowych stwierdzono w próbach o pH 4,5. Wartości składowych barwy X, Y, Z wzrastały w czasie ogrzewania, co związane jest ze spadkiem zawartości barwników fioletowych. Parametr L* określający jasność, a* określający udział barwy czerwonej oraz parametr b* określający udział barwy żółtej wzrastały w czasie ogrzewania. Największy wpływ na zmianę tych wyróżników miał czas ogrzewania, a najmniejszy wpływ miało pH. Wartość tonu barwy h* wzrastała w czasie ogrzewania, co wskazuje na zmianę barwy w kierunku żółtej.
EN
The aim of this study was to determine the changes of colour parameters and betalain pigments contents in solutions of red beet juice concentrate (14% extract) during heating in dependence on pH, time and temperature of heating. Analyses were conducted in model systems using the response surface method according to Box-Behnken design. During heating of solutions, violet betalain contents decreased with an increase in time and temperature of heating. The pH value had the greatest effect on yellow betalain pigment contents. The highest stability of betalains was determined in pH 4,5. Values of the X, Y and Z components increased during heating, what was associated with decreasing of violet pigment contents. Lightness of colour L*, the share of the red colour a* and share of the yellow colour b* increased during heating. The time of heating had the greatest effect on these responses, the effect of pH value was relatively small. Values of hue angle h* increased, what indicate a change in colour tone towards yellow.
10
Stability of Betanidin Influenced by Copper Cations
Tuwalska D., Starzak K., Szot D., Skopińska A., Wybraniec S.
Logistyka
|
2013
|
nr 4
EN
Latest studies revealed some antioxidant properties of betalain pigments that contribute to the growth of interest in these compounds. During the isolation and storage, betalains are exposed to many different chemical and physical degradative factors, which often lead to their decomposition and discoloration. An effect of copper cations on betanidin stability was investigated in aqueous and organic-aqueous solutions. Betanidin stability experiments were performed at different pH’s, with different concentrations of metal cations and in different solvents. Using the modern spectrophotometric microplate reader it was possible to monitor changes of absorption spectra of the pigment samples during their incubation with copper ions in parallel at various physico-chemical conditions. Incubation with copper cations leads to betanidin degradation in all investigated solvents in the whole range of pH. The formed products are its new oxidized derivatives. A possibility of a formation of metal-pigment complexes is also considered. Recognition of betalains degradation paths is important because of their not yet fully recognized antioxidant and chemopreventive properties.
PL
Ostatnie badania wykazały przeciwutleniające właściwości betalain, co przyczyniło się do wzrostu zainteresowania tą grupą związków. Podczas izolacji i przechowywania, betalainy są narażone na wiele różnych degradujących czynników, chemicznych i fizycznych, które często powodują ich rozkład i odbarwienie. Zbadano wpływ kationów miedzi na stabilność betanidyny w roztworach wodnych i wodno-organicznych. Eksperymenty były przeprowadzane w różnym pH, z różnymi stężeniami kationów metalu i rozpuszczalników organicznych. Zastosowanie nowoczesnego spektrofotometrycznego czytnika mikropłytek pozwoliło na monitorowanie zmian w widmie absorpcyjnym pigmentu w różnych warunkach fizyko-chemicznych. Inkubacja betanidyny z jonami miedzi prowadzi do jej degradacji we wszystkich badanych rozpuszczalnikach w całym zakresie pH. Powstałe produkty są jej nowymi, utlenionymi pochodnymi. Rozważano również powstawanie kompleksu metal-pigment.Poznanie szlaków utleniania betalain jest ważne z powodu nie w pełni jeszcze poznanych ich antyutleniających i chemoprewencyjnych właściwości.
11
Badania właściwości przeciwutleniających związków pochodzących z najczęściej spożywanych owoców i warzyw
Śmiechowska A., Kusznierewicz B., Bartoszek A., Namieśnik J.
Analityka : nauka i praktyka
|
2009
|
nr 2
20-25
12
Badania właściwości przeciwutleniających związków pochodzących z najczęściej spożywanych owoców i warzyw
Śmiechowska A., Kusznierewicz B., Bartoszek A., Namieśnik J.
Analityka : nauka i praktyka
|
2008
|
nr 4
26-30
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