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 "Wybraniec, S." wg kryterium: Autor

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 25
Tytuł:
Transformations and visualization of potential field data
Autorzy:
Wybraniec, S.
Powiązania:
https://bibliotekanauki.pl/articles/1188042.pdf
Data publikacji:
1999
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
pola potencjalne
transformacje
filtracja cyfrowa
wizualizacja
obrazy wektorowe
Polska
Europa
potential fields
transformations
digital filtering
visualization
vectorial images
Polska
Europe
Opis:
Transformacje są bardzo ważnym krokiem w interpretacji pól potencjalnych. Można je nawet traktować jako niezależną metodę interpretacji (Blakely, 1996). To samo można powiedzieć o wizualizacji tych danych. W pracy przedstawiono wyniki badań podjętych przez autora w obu tych dziedzinach. Od strony transformacji przedstawiono nowy sposób liczenia dwuwymiarowych (2D) filtrów cyfrowych bazujących na transformacji Fouriera-Hankela, opracowany przez autora i stosowany już od wielu lat w praktyce; zaproponowano nowe metody transformacji oparte na pojęciu pochodnych i całek ułamkowych; podkreślono wagę trójwymiarowej transformacji Hilberta i pojęcia sygnału analitycznego w transformacjach pól potencjalnych, a także dowolnych danych powierzchniowych; zdefiniowano pojęcie składowych kierunkowych. Od strony wizualizacji przedstawiono nowe metody obrazowania danych pól potencjalnych, m.in. obrazy wektorowe, które można wykorzystać także do prezentacji danych skalarnych, po ich transformacji do sygnału analitycznego. Pokazano wiele przykładów zastosowania proponowanych metod transformacji i wizualizacji z wykorzystaniem głównie danych polskich (dane grawimetryczne i magnetyczne), a także europejskich (dane grawimetryczne). Przedstawione metody można zastosować także do danych pól niepotencjalnych, co zademonstrowano na przykładzie obrazów przedstawiających transformowane dane hipsometryczne Polski.
Źródło:
Polish Geological Institute Special Papers; 1999, 1; 1-88
1507-9791
Pojawia się w:
Polish Geological Institute Special Papers
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on dehydrogenation of gomphrenin in heated ammonia solutions of organic solvents
Autorzy:
Szmyr, N.
Wybraniec, S.
Powiązania:
https://bibliotekanauki.pl/articles/115847.pdf
Data publikacji:
2017
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
Gomphrena globosa
Betalains
Betacyanins
Gomphrenin
LC-DAD-ESI-MS
dehydrogenation
decarboxylation
Gomfrena kulista
betalainy
betacyjaniny
gomphereniny
odwodnienie
dekarboksylacja
Opis:
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.
Źródło:
Challenges of Modern Technology; 2017, 8, 1; 8-12
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study of pigments associated with cell walls of calli of some Cactaceae species
Autorzy:
Lystvan, K.
Wybraniec, S.
Powiązania:
https://bibliotekanauki.pl/articles/80626.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
pigment
cell wall
callus cell
Mammillaria multiceps
Cactaceae
stress condition
dimethyl sulphoxide
antimicrobial activity
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 3
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on stability of gomphrenin pigments influenced by Cu2+ ions
Autorzy:
Szmyr, N.
Wybraniec, S.
Powiązania:
https://bibliotekanauki.pl/articles/115831.pdf
Data publikacji:
2017
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
Gomphrena globosa
Betalains
Betacyanins
Gomphrenin
LC-DAD-ESI-MS
dehydrogenation
decarboxylation
Gomfrena kulista
betalainy
betacyjaniny
gomphereniny
odwodnienie
dekarboksylacja
Opis:
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.
Źródło:
Challenges of Modern Technology; 2017, 8, 1; 13-18
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of EDTA on stabilization of decarboxylated betalains
Autorzy:
Skopińska, A.
Starzak, K.
Wybraniec, S.
Powiązania:
https://bibliotekanauki.pl/articles/115483.pdf
Data publikacji:
2012
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
betacyanins
decarboxylation
Beta vulgaris L.
EDTA
Opis:
Betalains are known to be very sensitive to several factors, including higher temperature, therefore, the studies on their stability are essential for the food industry. In order to determine the stability of betanin derivatives during thermal treatment, a set of degradation experiments was performed, including the protective infl uence of EDTA as a chelating agent. The pigments were dissolved in aqueous solutions of acetonitrile, methanol and ethanol. The studies on thermal degradation of the pigments confi rmed their high lability in all investigated solvents. Under the infl uence of protective activity of EDTA, the rate of the degradation of the decarboxylated betalains was substantially decreased. The analysis of obtained absorption spectra of the degradation products indicated that under the infl uence of EDTA, the products retained the basic chromophoric skeleton.
Źródło:
Challenges of Modern Technology; 2012, 3, 4; 29-33
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on betanidin oxidation by ABTS radicals
Autorzy:
Starzak, K.
Skopińska, A.
Wybraniec, S.
Powiązania:
https://bibliotekanauki.pl/articles/115792.pdf
Data publikacji:
2012
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
betanidin
betalains
antioxidation activity
ABTS
radicals
Opis:
Betanidin is a basic betacyanin with 5,6-dihydroxyl moiety which causes its high antioxidant activity. It belongs to betalains, a group of natural, water-soluble plant pigments, which elicit a red-violet coloration of fruits and fl owers. One of the most popular sources of betanidin is red beet root (Beta vulgaris L.). Recent studies have shown importance of betalains oxidation, because of their high natural, antiradical and antioxidant activity and potential benefi ts for human health [1]. An eff ect of oxidation of betanidin using ABTS radicals was investigated in aqueous solutions at pH 3–8 and compared to activity of horseradish peroxidase. Products of the biomimetic betanidin oxidation were monitored by high performance liquid chromatography (HPLC) coupled to optical detection and mass spectrometry (LC-DAD-ESI-MS/MS). The presence of two main oxidation products: 2-decarboxy-2,3-dehydro-betanidin and 2,17-didecarboxy-2,3-dehydro- -betanidin at pH 3 indicates their generation through two possible reaction ways with two diff erent quinonoid intermediates: dopachrome derivative and quinone methide. Both reaction paths lead to the decarboxylative dehydrogenation of betanidin.
Źródło:
Challenges of Modern Technology; 2012, 3, 4; 39-43
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porownanie zawartosci witamin B1 i B2 w mrozonkach i sterylizowanych konserwach z boczniaka, borowika i pieczarki
Comparing the vitamin B1 and B2 content levels in frozen and sterilized canned foodstuffs of Pleurotus ostreatus, Boletus edulis, and Agaricus bisporus
Autorzy:
Jaworska, G
Biernacka, A.
Wybraniec, S.
Bernas, E.
Powiązania:
https://bibliotekanauki.pl/articles/826618.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Technologów Żywności
Tematy:
grzyby jadalne
konserwy sterylizowane
mrozonki
boczniak ostrygowaty
Pleurotus ostreatus
Boletus edulis
borowik szlachetny
Agaricus bisporus
pieczarka dwuzarodnikowa
witamina B1
witamina B2
zawartosc witamin
tiamina
ryboflawina
Opis:
Celem pracy było porównanie zawartości witamin B1 i B2 w mrożonkach i konserwach sterylizowanych otrzymanych z owocników boczniaka ostrygowatego (Pleurotus ostreatus (Jacq.: Fr.) Kumm.), borowika szlachetnego (Boletus edulis (Bull: Fr.)) i pieczarki dwuzarodnikowej (Agaricus bisporus (Lange) Sing.), poddanych przed konserwowaniem blanszowaniu w wodzie oraz w roztworze wodnym pirosiarczynu sodu i kwasu cytrynowego. Witaminy analizowano symultanicznie, metodą HPLC. Zawartość tiaminy w produktach wahała się od 0,008 do 0,211 mg w 100 g świeżej masy i od 0,09 do 2,21 mg w 100 g suchej masy, natomiast ryboflawiny odpowiednio od 0,039 do 0,252 mg i od 0,44 do 2,87 mg. Największy wpływ na zróżnicowanie poziomu witamin miał gatunek grzyba. Najmniej oznaczanych witamin zawierały produkty z boczniaka. Najwięcej tiaminy występowało w wyrobach z borowika, a pod względem zawartości ryboflawiny dominowały produkty z pieczarki i z borowika. Mrożonki, w porównaniu z konserwami, były bogatsze w witaminę B1 średnio 3,5-krotnie, a w witaminę B2 o około 25%. Użycie pirosiarczanu(IV) sodu i kwasu cytrynowego do blanszowania spowodowało zmniejszenie zawartości tiaminy w produktach średnio o 33%.
The objective of the paper was to compare the content levels of vitamin B1 and B2 in frozen and sterilized canned foodstuffs made of pilei of the following mushrooms: Boletus edulis (Bull: Fr.), Pleurotus osteatus (Jacq.: Fr.) Kumm.) and Agaricus bisporus (Lange) Sing.). Prior to preservation, the pilei of mushrooms were blanched in water and water solutions of sodium metabisulfite and citric acid. Vitamins were simultaneously analyzed using an HPLC method. In the products investigated, the thiamine content ranged from 0.008 to 0.211 mg /100 g of fresh matter, and from 0.09 to 2.21 mg per 100 g dry matter, and the riboflavin content was from 0.039 to 0.252 mg, and from 0.44 to 2.87 mg, respectively. The mushroom species had the greatest effect on the different content level of vitamins in mushrooms. The content level of vitamins determined was the lowest in Pleurotus osteatus mushrooms. The highest content of thiamine was determined in Boletus edulis, and the contents of riboflavins were the highest in both the Agaricus bisporus and the Boletus edulis products. The content level of vitamin B1 in frozen products was averagely 3.5 times higher than in the canned products, and the content of vitamin B2 – by about 25%. When sodium metabisufite and citric acid were used for blanching, the thiamine content in the foodstuffs investigated decreased, averagely, by 33%.
Źródło:
Żywność Nauka Technologia Jakość; 2007, 14, 6
1425-6959
Pojawia się w:
Żywność Nauka Technologia Jakość
Dostawca treści:
Biblioteka Nauki
Artykuł
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:
High salt-solvent systems in separation of betanin and its derivatives from red beet (Beta vulgaris L.) by high-performance countercurrent chromatography (HPCCC)
Autorzy:
Spórna-Kucab, A.
Ignatova, S,
Garrard, I.
Wybraniec, S.
Powiązania:
https://bibliotekanauki.pl/articles/115564.pdf
Data publikacji:
2012
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
betanin
betalains
betacyanins
countercurrent chromatography
Beta vulgaris L.
Opis:
A study on a separation of betanin and its decarboxy- and dehydro-derivatives obtained from red beet roots (Beta vulgaris L.) using analytical high-performance countercurrent chromatography (HPCCC — Dynamic Extractions Ltd., UK) was performed. The HPCCC process was accomplished in the ‘tail to head’ mode with three highly polar solvent systems with high salt concentrations: 1-propanol-acetonitrile-saturated ammonium sulphate-water (v/v/v/v, 1:0.5:1.2:1); ethanol-acetonitrile-1- propanol-saturated ammonium sulphate-water (v/v/v/v/v, 0.5:0.5:0.5:1.2:1) and ethanol-1-butanol-acetonitrile-saturated ammonium sulphate-water (volume ratio), 0.5:0.5:0.5:1.2:1). HPLC analysis was performed in a conventional reversed phase mode with diode-array (DAD) detection to characterize the composition of obtained fractions. The applied solvent systems enabled the separation of the betalain pigments with high efficiency for the first time. In the mode of separation selected, the more hydrophobic compounds eluted first as expected. Moreover, for the first time, the applied HPCCC solvent systems generated a separation of 2-decarboxy-betanin from 17- and 2,17-bidecarboxy-betanin as well as from neobetanin and betanin.
Źródło:
Challenges of Modern Technology; 2012, 3, 1; 57-61
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
Wyświetlanie 1-15 z 25

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