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Wyświetlanie 1-15 z 93
Tytuł:
A Contribution to the Study of Traces of Psychotropic Substances Inside Miniature Vessels and Collared Flasks of the Eneolithic Funnel Beaker culture (FBC) from Poland
Autorzy:
Taras, Halina
Zakościelna, Anna
Osak, Marcin
Buszewicz, Grzegorz
Teresiński, Grzegorz
Powiązania:
https://bibliotekanauki.pl/articles/38620704.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Rzeszowski. Instytut Archeologii Uniwersytetu Rzeszowskiego. Muzeum Okręgowe w Rzeszowie
Tematy:
psychoactive substances
miniature vessels
Eneolithic
SE group of the FBC
Polska
GC-MS/MS
LC-MS/MS
Opis:
The text presents the results of laboratory analyses conducted on vegetal intoxicating substances identified on the walls of selected pottery forms discovered at Polish sites attributed to the south-eastern group of the FBC. The samples taken from miniature vessels and collared flasks were examined using the GC-MS/MS method (triple quadrupole) and then the reference method LC-MS/MS (linear ion trap). As a result of the research, psychotropic substances were identified in four samples: papaverine, scopolamine and atropine.  
Źródło:
Analecta Archaeologica Ressoviensia; 2023, 18; 97-102
2084-4409
Pojawia się w:
Analecta Archaeologica Ressoviensia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Note on Gödel-Dummet Logic LC
Autorzy:
Robles, Gemma
Méndez, José M.
Powiązania:
https://bibliotekanauki.pl/articles/2033854.pdf
Data publikacji:
2021-07-01
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
Intermediate logics
Gödel-Dummet logic LC
Opis:
Let \(A_{0},A_{1},...,A_{n}\) be (possibly) distintict wffs, \(n\) being an odd number equal to or greater than 1. Intuitionistic Propositional Logic IPC plus the axiom \((A_{0}\rightarrow A_{1})\vee ...\vee (A_{n-1}\rightarrow A_{n})\vee (A_{n}\rightarrow A_{0})\) is equivalent to Gödel-Dummett logic LC. However, if \(n\) is an even number equal to or greater than 2, IPC plus the said axiom is a sublogic of LC.
Źródło:
Bulletin of the Section of Logic; 2021, 50, 3; 325-335
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A state-space approach for control of NPC type 3-level sine wave inverter used in FOC PMSM drive
Autorzy:
Tarczewski, T.
Grzesiak, L. M.
Wawrzak, A.
Karwowski, K.
Erwiński, K.
Powiązania:
https://bibliotekanauki.pl/articles/200731.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
state feedback control
linear quadratic regulator
3-level neutral point clamped voltage source inverter
LC filter
Opis:
This paper presents the design and analysis process of state feedback controllers for NPC type 3-level sine wave inverter. In order to achieve good dynamic features in a state feedback control an internal model of reference input and a feedforward path are introduced. During synthesis process of the state feedback controllers maximum permissible dynamics of voltage control in the linear range of modulation is taken into account. It is shown that initially gains of the controller and feedforward path are non-stationary and depend on the angular velocity. Stationary approximation of a non-stationary state feedback controller is presented in details. Proposed state feedback control structures for continuous voltage shaping NPC type 3-level voltage source inverter are examined in FOC PMSM drive. The novelty of the presented controller lays in a stationary approximated state feedback control structure designed in terms of maximum permissible dynamics of a voltage control system. Simulation and experimental results (at the level of 3 kW) of the designed control algorithms are included.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2014, 62, 3; 439-448
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A WebGIS framework for disseminating processed remotely sensed on land cover transformations
Autorzy:
Caradonna, G.
Novelli, A.
Tarantino, E.
Cefalo, R.
Fratino, U.
Powiązania:
https://bibliotekanauki.pl/articles/106878.pdf
Data publikacji:
2016
Wydawca:
Politechnika Warszawska. Wydział Geodezji i Kartografii
Tematy:
WebGIS
satellite data
LU/LC
vegetation analysis
dane satelitarne
analiza roślinności
Opis:
Mediterranean regions have experienced significant soil degradation over the past decades. In this context, careful land observation using satellite data is crucial for understanding the long-term usage patterns of natural resources and facilitating their sustainable management to monitor and evaluate the potential degradation. Given the environmental and political interest on this problem, there is urgent need for a centralized repository and mechanism to share geospatial data, information and maps of land change. Geospatial data collecting is one of the most important task for many users because there are significant barriers in accessing and using data. This limit could be overcome by implementing a WebGIS through a combination of existing free and open source software for geographic information systems (FOSS4G). In this paper we preliminary discuss methods for collecting raster data in a geodatabase by processing open multi-temporal and multi-scale satellite data aimed at retrieving indicators for land degradation phenomenon (i.e. land cover/land use analysis, vegetation indices, trend analysis, etc.). Then we describe a methodology for designing a WebGIS framework in order to disseminate information through maps for territory monitoring. Basic WebGIS functions were extended with the help of POSTGIS database and OpenLayers libraries. Geoserver was customized to set up and enhance the website functions developing various advanced queries using PostgreSQL and innovative tools to carry out efficiently multi-layer overlay analysis. The end-product is a simple system that provides the opportunity not only to consult interactively but also download processed remote sensing data.
Źródło:
Reports on Geodesy and Geoinformatics; 2016, 100; 27-38
2391-8365
2391-8152
Pojawia się w:
Reports on Geodesy and Geoinformatics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acrylamide content in cigarette mainstream smoke and estimation of exposure to acrylamide from tobacco smoke in Poland
Autorzy:
Mojska, Hanna
Gielecińska, Iwona
Cendrowski, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/989240.pdf
Data publikacji:
2016
Wydawca:
Instytut Medycyny Wsi
Tematy:
acrylamide
cigarette mainstream smoke
lc-ms/ms
exposure assessment
Opis:
Introduction and objective. Acrylamide is a “probably human carcinogen” monomer that can form in heated starchy food as a result of a reaction between asparagine and reducing sugars via Maillard reaction. The main source of acrylamide in human diet are potato products, cereal products and coffee. Tobacco smoke may be another significant source of exposure to acrylamide. The aim of our study was to determine acrylamide content in cigarettes available on the Polish market and to estimate the exposure to acrylamide originating from tobacco smoke in smokers in Poland. Materials and methods. The material was cigarettes of the top five brands bought in Poland and tobacco from non-smoked cigarettes. Acrylamide content in cigarettes mainstream smoke was determined by LC-MS/MS. Exposure assessment was carried out using analytical data of acrylamide content in cigarettes and the mean quantity of cigarettes smoked daily by smokers in Poland, assuming body weight at 70 kg. Results. The mean content of acrylamide was 679.3 ng/cigarette (range: 455.0 – 822.5 ng/cigarette). The content of acrylamide was evidenced to correlate positively with total particulate matter (TPM) content in cigarettes. The estimated average exposure to acrylamide from tobacco smoke in adult smokers in Poland is 0.17 μg/kg b.w./day. Conclusions. Our results demonstrate that tobacco smoke is a significant source of acrylamide and total exposure to acrylamide in the population of smokers, on average, is higher by more than 50% in comparison with non-smokers. Our estimation of exposure to acrylamide from tobacco smoke is the first estimation taking into account the actual determined acrylamide content in the cigarettes available on the market.
Źródło:
Annals of Agricultural and Environmental Medicine; 2016, 23, 3
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Addition of bisulfite ions to methyl vinyl ketone and methacrolein relevant to atmospheric processes
Przyłączanie anionów wodorosiarczynowych do ketonu metylowo-winylowego i metakroleiny o znaczeniu dla procesów atmosferycznych
Autorzy:
Szmigielski, R.
Rudziński, K. J.
Powiązania:
https://bibliotekanauki.pl/articles/953669.pdf
Data publikacji:
2013
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
proces atmosferyczny
wtórny aerosol atmosferyczny
stałe szybkości
spektrometria mas
detekcja elektrosprej
LC MS
izopren
metakroleina
keton metylowo-winylowy
ditlenek siarki
addycja wodorosiaczynu
związki karbonylowe
atmospheric processes
secondary organic aerosols
rate constants
electrospray mass spectrometry
LC-MS
isoprene
methacrolein
methyl vinyl ketone
sulfur dioxide
bisulfite addition
carbonyls
Opis:
Metakroleina oraz keton metylowo-winylowy są bardzo reaktywnymi zawiązkami karbonylowymi, które odgrywają istotną rolę w procesach atmosferycznych, w tym – w tworzeniu pyłów zwieszonych w powietrzu. Obydwa związki są produktami utleniania izoprenu – węglowodoru emitowanego do atmosfery w ogromnych ilościach. W pracy przedyskutowano mechanizmy chemiczne zaniku metakroleiny oraz ketonu metylowo-winylowego w wyniku addycji anionu wodorosiarczanowego w rozcieńczonych roztworach wodnych, odzwierciedlające procesy zachodzące w kroplach wód atmosferycznych w rejonach o znaczącym stężeniu ditlenku siarki. W pracy pokazano, że reakcje addycji anionu wodorosiarczynowego do badanych związków karbonylowych prowadzą do tworzenia pierwotnych i wtórnych hydroksysulfonianów, które mogą uczestniczyć w tworzeniu aerozoli atmosferycznych. Wyznaczono stałe szybkości wszystkich reakcji w mechanizmie addycji. Pierwotna addycja anionów wodorosiarczynowych do metakroleiny okazała się znacznie szybsza niż do ketonu metylowo-winylowego (stałe szybkości kMAC1f = 8 i kMVK1f = 0.18 mol–1 dm3 s–1 w temperaturach pokojowych). Stała szybkości addycji do cząsteczki metakroleiny była dziesięciokrotnie większa od stałej opublikowanej w literaturze. Analiza kinetyczna i badania produktów reakcji za pomocą spektrometrii mas wykazały, że w przypadku każdego z badanych związków karbonylowych dominującym produktem reakcji był C4 alfa-hydroksysulfonian (addukt pierwotny), natomiast C4 hydroksydwusulfonian (addukt wtórny, diaddukt) powstawał w ilościach śladowych. Pierwotna addycja anionów wodorosiarczynowych do metakroleiny i ketonu metylowo-winylowego może mieć znaczenie w konwersji reaktywnych związków karbonylowych w atmosferze i powinna być uwzględniana w badaniach dotyczących rejonów o znaczącej obecności ditlenku siarki, gwarantującej wysokie stężenia anionów wodorosiarczynowych w wodach atmosferycznych.
Methacrolein and methyl vinyl ketone are highly reactive carbonyls that play a pivotal role in the formation of secondary organic aerosols in the Earth’s atmosphere. Both carbonyls are the major products of isoprene oxidation. We show that among the atmospheric sinks of methacrolein and methyl vinyl ketone, the aqueous-phase addition of bisulfite anions to their molecules can be relevant under polluted conditions with the increased presence of sulfur dioxide. We demonstrate that aqueous-phase reactions of methyl vinyl ketone and methacrolein with bisulfite anions lead to the formation of primary and secondary organic hydroxysulfonates which currently are not included in the atmospheric chemistry modelling, but can be relevant in mechanisms explaining the formation and growth of the secondary organic aerosols from atmospheric carbonyls. The rate constants for all aqueous-phase reactions involved were determined. The primary addition of bisulfite anions to methacrolein was found significantly faster than that to methyl vinyl ketone, with rate constants kMAC1f = 8 and kMVK1f = 0.18 mol–1 dm3 s–1 at room temperatures, respectively. The rate constant for the bisulfite addition to methacrolein was ten times faster than reported in the literature. The kinetic and mass spectrometric analyses revealed that in both cases, the dominating product was the C4 alpha-hydroxysulfonate (a primary adduct), while the C4 alpha-hydroxy disulfonate (a secondary adduct or diadduct) was produced only in trace quantities. The primary addition of bisufite anions to methacrolein and methyl vinyl ketone should be considered in atmospheric studies relevant to areas with enhanced presence of sulfur dioxide providing sufficiently high concentrations of bisulfite ions in atmospheric waters.
Źródło:
Ecological Chemistry and Engineering. A; 2013, 20, 9; 935-949
1898-6188
2084-4530
Pojawia się w:
Ecological Chemistry and Engineering. A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adjusting output impedance using a PI controller to improve the stability of a single-phase inverter under weak grid
Autorzy:
Jiao, J.
Nelms, R. M.
Powiązania:
https://bibliotekanauki.pl/articles/136224.pdf
Data publikacji:
2016
Wydawca:
EEEIC International Barbara Leonowicz Szabłowska
Tematy:
grid impedance
inverter output impedance
LC filter
PI controller
single-phase inverter
Opis:
Explored in this paper is the grid impedance effect on the stability of a single-phase grid connected inverter with an LC filter based on an analysis of the inverter output impedance. For a single-phase grid connected inverter, a PI controller is often used to regulate the current injected into the grid. However, the control performance can be influenced when the inverter is connected to a weak grid. Also, the utility grid has background harmonic noise, which can make the injected current distorted. Therefore, analysis of the output impedance of a single-phase grid connected inverter is important for the robustness and stability of the system. By modeling the output impedance of inverter, it can be determined that the proportional gain and integral gain of the controller have an effect on the output impedance. Analytical results show that by adjusting the PI controller parameters, the ability for harmonic reduction and stability of the system can be improved. Simulation and experiments using a 1 kW single-phase grid connected inverter verify the effectiveness of the theoretical analysis.
Źródło:
Transactions on Environment and Electrical Engineering; 2016, 1, 4; 50-57
2450-5730
Pojawia się w:
Transactions on Environment and Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analytical strategies for assessing occupational exposure to antineoplastic drugs in healthcare workplaces
Autorzy:
Dugheri, Stefano
Bonari, Alessandro
Pompilio, Ilenia
Boccalon, Pierpaolo
Tognoni, Daniela
Cecchi, Michele
Ughi, Massimo
Mucci, Nicola
Arcangeli, Giulio
Powiązania:
https://bibliotekanauki.pl/articles/2162575.pdf
Data publikacji:
2018-12-18
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
occupational exposure
LC-MS/MS
ICP-MS
urine
antineoplastic drugs
wipe test
Opis:
Background Cytotoxic antineoplastic drugs (ADs), widely used in treating cancer, are considered hazardous in the workplace and thus require safe handling practices. An analytical protocol for environmental and biological AD monitoring in the healthcare environment has been developed, since Europe lacks clear guidelines and regulations for cytostatic preparation and handling. Material and Methods Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for measuring contemporaneously 20 multi-class cytostatic compounds and urinary α-fluoro-β-alanine, whereas platinum was detected by inductively coupled plasma mass spectrometry (ICP-MS). Sampling procedures and analytical conditions were optimized and the assays were validated. Environmental AD monitoring data, collected in 2009–2017, for a total of 3749 wipe tests and 57 720 determinations, was evaluated. Results The proportion of positive samples gradually decreased from 11.7% in 2010 to 1% in 2017, however, 2266 determinations were positive. No urine sample had detectable concentrations of any of the 4 drugs considered (0/398 samples). Conclusions These improvements are so large that the key role played by the new, more stringent rules for preparing and administering ADs is evident. Hence, the analytical method involving multi-element determinations allows for a more thorough and complete investigation into the AD contamination of work environments. Med Pr 2018;69(6):589–604
Źródło:
Medycyna Pracy; 2018, 69, 6; 589-604
0465-5893
2353-1339
Pojawia się w:
Medycyna Pracy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Atomic Motion in Amorphous Solids
Autorzy:
Schober, H.
Powiązania:
https://bibliotekanauki.pl/articles/2035455.pdf
Data publikacji:
2002-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.43.Fs
61.20.Lc
81.05.Kf
Opis:
Glasses and amorphous materials show, coexisting with the sound waves, a variety of low energy excitations: tunneling, quasi-localized vibrations and relaxations. The latter two are observed well into the liquid state. Using molecular dynamics both were shown to be centred on more than ten atoms or molecular units, which form chain-like structures. With increasing frequency the interaction of the quasi-localized modes with the sound waves and with each other increases, they delocalize. However, even at the so-called boson peak frequency, where the sound waves become overdamped due to the interaction, the vibrations can be decomposed into local and extended modes. Closely correlated with the local vibrations are the local relaxations, which can be envisaged as collective jumps of groups of atoms. With rising temperature both the total jump length and the number of atoms participating increases. In the melt when single jumps are no longer resolved one still observes a collective motion of chains of atoms.
Źródło:
Acta Physica Polonica A; 2002, 102, 1; 83-93
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Betaxanthin Profiling in Beta vulgaris Leaves and Gymnocalycium mihanovichii Grafted Cacti: A Comprehensive Study
Autorzy:
Spórna-Kucab, Aneta
Tekieli, Anna
Knapek, Magdalena
Zużałek, Marta
Wybraniec, Sławomir
Powiązania:
https://bibliotekanauki.pl/articles/24024625.pdf
Data publikacji:
2023-12-05
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
beet
betalains
colorants
grafted cactus
LC-MS
secondary metabolites
Opis:
This study was focused on the identification and quantification of betaxanthins using high-performance liquid chromatography with a diode array detector coupled to electrospray ionisation mass spectrometry (HPLC-DAD-ESI-MS) in leaves of various cultivars of Beta vulgaris (beet) and Gymnocalycium mihanovichii grafted cacti. In G. mihanovichii grafted cacti, four betaxanthins, namely histidine-Bx, histamine-Bx, serine-Bx, and proline-Bx, were tentatively identified in the yellow, orange, pink, and red varieties, with contents ranging from 0.09 to 1.55 mg/kg fresh weight (FW). Betaxanthins were not detected in the green cactus. Histidine-Bx was the prevailing betaxanthin compound in the majority of cultivars. Fifteen betaxanthins were successfully identified in the leaves of five B. vulgaris cultivars (cv.): Snow Ball, Boldor, Cylindra, Rhubarb, and Round Dark Red. Leaves of yellow beet (cv. Boldor) had the highest total betaxanthin content (20.4 mg/kg FW), while white beet (cv. Snow Ball) had the lowest one (3.43 mg/kg FW). The leaves of red cultivars had comparable betaxanthin contents, ranging from 13.4 to 18.8 mg/kg FW, similary to the yellow cultivar, indicating their potential as valuable sources of betaxanthins. There was no single dominant betaxanthin in B. vulgaris leaves. The leaves of B. vulgaris were found to be a richer source of betaxanthin than the grafted cactus G. mihanovichii, which opens up new prospects for research into the potential utilization of these compounds in the industry.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2023, 73, 4; 375-384
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bioinformatic insight into Portulaca oleracea L. (Purslane) of Bulgarian and Greek origin
Autorzy:
Balabanova, V.
Hristov, I.
Zheleva-Dimitrova, D.
Sugareva, P.
Lozanov, V.
Gevrenova, R.
Powiązania:
https://bibliotekanauki.pl/articles/2117810.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Portulaca oleracea
LC–HRAMS
secondary metabolites
descriptive analysis
multivariate statistics
Opis:
Portulaca oleracea L. (Portulacaceae) is used as functional food and its nutritional and therapeutic properties are related to the high levels of organic and fatty acids, polyphenols, polysaccharides and cyclo-dopa amides. This study presents a strategy based on liquid chromatography – high resolution accurate mass spectrometry method (LC – HRAMS) and bioinformatic methods to analyze 33 purslane accessions originating from 11 floristic regions in Bulgaria together with 5 accessions of Greek provenance. Extracts were obtained by microwave extraction. Based on the LC-MS metabolic “fingerprints” of assayed samples, a purslane metabolic database was developed. LC-MS data were proceeded with Software application Compound Discover 2.0 (Thermo Fischer Sci., USA). Principal Component Analysis (PCA) combined with both descriptive and differential analyses were used to find marker metabolites to distinguish different geographical regions. The differential analysis of the Bulgarian and Greek samples allowed the identification of 50 marker metabolites. Based on accurate masses, retention times, fragmentation patterns in MS/MS, comparison with commercial standards and literature data, these secondary metabolites were identified after detailed analysis of Volcano-plots. For the first time, 29 compounds are reported. The identified compounds were used to perform a study of the biosynthetic pathways of purslane secondary metabolites using Kyoto Encyclopedia of Genes and Genomes (KEGG) software platform. The statistical treatments identified marker compounds that can be used to distinguish the origin of accession set. Combining LC-MS data with multivariate statistical analysis was shown to be effective in studying the purslane metabolites, allowing for integration of chemistry with geographic origin.
Źródło:
Acta Biologica Cracoviensia. Series Botanica; 2020, 62, 1; 7-21
0001-5296
Pojawia się w:
Acta Biologica Cracoviensia. Series Botanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cantor extension of a half lineary cyclically ordered group
Autorzy:
Černák, Štefan
Powiązania:
https://bibliotekanauki.pl/articles/728774.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
convergent sequence
fundamental sequence
C-complete half lc-group
Cantor extension of a half lc-group
Opis:
Convergent and fundamental sequences are studied in a half linearly cyclically ordered group G with the abelian increasing part. The main result is the construction of the Cantor extension of G.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2001, 21, 1; 31-46
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chaos via Period-Doubling Oscillations in an Exciton-Carrier-Photon System Driven by Optical Pumping
Autorzy:
Nguyen, Ba An
Powiązania:
https://bibliotekanauki.pl/articles/1930622.pdf
Data publikacji:
1994-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.65.-k
71.35.+z
42.50.Lc
Opis:
A detailed stability analysis is performed for a highly excited semiconductor modelled as an exciton-electron-hole-photon system driven externally by optical pumping. Chaotic self-pulsations are shown to occur on both the upper and lower branches of the bistable steady state curve of the system via a sequence of period-doubling oscillation process. Such a route to chaos is well known in laser physics and in other nonlinear systems but not in highly excited semiconductors yet.
Źródło:
Acta Physica Polonica A; 1994, 85, 3; 541-552
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Triterpene Saponin Composition of White, Yellow and Red Beetroot (Beta vulgaris L.)
Autorzy:
Spórna-Kucab, Aneta
Tekieli, Anna
Skalicka-Woźniak, Krystyna
Grzegorczyk, Agnieszka
Świergosz, Tomasz
Wybraniec, Sławomir
Powiązania:
https://bibliotekanauki.pl/articles/2051041.pdf
Data publikacji:
2022-06-06
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
betavulgarosides
Beta vulgaris L
food composition
LC-MS/MS
oleanolic acid
saponins
Opis:
Beta vulgaris L. is an important source of bioactive saponins – a group of secondary metabolites – that have spurred a growing interest due to their health-promoting properties. This study aimed to gain information on triterpene saponin profile of the peel and flesh of white, yellow and red beet of six cultivars – Snow Ball, Boldor, Ceryl, Chrobry, Forono and Tytus – harvested in Poland, in the same region. Twenty four saponins with oleanolic acid, hederagenin, akebonoic acid and gypsogenin as aglycons were identified and quantified by liquid chromatography/tandem mass spectrometry (LC-ESI-MS/MS). Among them, betavulgaroside I, II, III and IV were the major compounds, but the quantitative profile of saponins was found to be dependent on beet cultivar and root part, respectively. The highest content of saponins was found in the peel of yellow B. vulgaris Boldor (20812 mg/kg fresh weight, fw), while the lowest saponin content was determined in the flesh of white B. vulgaris Snow Ball (497 mg/kg fw). In addition, the total saponin content in peel and flesh in yellow beet (26054 mg/kg fw) was much higher than the total content in peel and flesh in red beet Tytus (8364 mg/kg fw) and white beet Snow Ball (1204 mg/kg fw). This is the first report on the profile of saponins in white and yellow beets.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2022, 72, 2; 159-170
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
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
Wyświetlanie 1-15 z 93

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