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Estudo fitoquímico e citotóxico de Oleorresinas de BurseraceaeRudiger, André Luis 01 November 2012 (has links)
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Previous issue date: 2012-11-01 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PHYTOCHEMICAL AND CITOTOXIC STUDY OF BURSERACEAE OLEORESINS.
The Burseraceae family includes approximately 700 specimens distributed in 19 genres, and
many of these specimens do not present phytochemical studies. Interested on describing the
chemical composition, evaluate the cytotoxic activity and isolate substances of chemical and
cytotoxic interest, this work has been divided in three parts: Determination of the extraction in
hexane chemical profiles; cytotoxicity evaluation of oleoresins against HCT-8 (collon),
MDA/MB-435 (breast) and SF-295 (glioblastom); and isolation of substances present in the
oleoresins. The isolated substances were identified by mass spectrometry techniques (GC-MS
and ESI-IT-MS) and nuclear magnetic resonance (NMR). In the volatile compounds profile it
was possible to observe that among the monoterpenes, the p-cymene was detected more times,
in 11 out 23 specimens evaluated. The highest concentration of this compound was observed
in Protium apiculatum (2.4%), however the compound mostly found in this specimen is αpinene
(5.1%). Among the sesquiterpenes, the compound that presented highest concentration
was the junenol, in P. cf. rubrum (23.9%) and P. cf. ferrugineum (11.3%) being isolated and
elucidated. The samples with the most complex sesquiterpenic profile were
P. tenuifolum and Tetragastris panamensis, with common detection of sesquiterpenes of
bisabolane, cadinane, cubebane, eudesmane, guaiane and muurulane series. The total ion
chromatograms evaluations showed the presence of α- and β-amyrin in all the samples,
confirming the presence of these triterpenes as family markers. In P. cf. ferrugineum, it has
been observed the absence of α- and β-amyrone, and it was the differential of this specimen
among other samples. About the triterpenes, glutinol (first description in the genres studied)
and the multiflorenol (first description in the family) were detected. The chemometric analysis
resulted in five distinct cluster (C-1 to C-5), where C-1 presented high concentration of α- and
β-amyrone and absence of brein and maniladiol; C-2, having potentially producers of new
triterpene and volatile compound specimens; C-3 with medium concentration among the
variables analyzed; C-4 with high concentration of brein and maniladiol; and C-5, having α-
and β-amyrin high concentration specimens. Te cititoxicity assays showed that two extracts in
hexane (P. cf. rubrum e Trattinnickia peruviana - HrTPE) showed inhibition against HCT-8
(93.08 % for both specimens) and SF-295 (93.46 e 86.34%, respectively) tumor cells lines. In
the extracts in acetate and acetyl, inhibition for P. giganteum var giganteum and Trattinnickia
glaziovii against HCT-8 (88.7 e 92.9%, respectively) and MDAM B-435 (97.8 e 96.2%,
respectively) lines were observed. HrTPE was submitted to fractioning, being identified the
β-amyradienol. From the extract in ethyl acetate of P. paniculatum var. modestum, breine and
maniladiol triterpenes in binary mixture, 3-hydroxy-tirucalla-8,24-diene-21-oic acid, pure
and in binary mixture with 3-hydroxy-tirucalla-7,24-dieno-21-oic acid were isolated. In the
P. bahianum ethyl acetate extract, the ursolic and oleanolic acids were isolated. From the
Tetragastris panamensis ethyl acetate extract, an unpublished triterpene (3-oxo-triptocallic B
acid) and two triterpenes decribed for the first time in the Burseraceae family (triptocallic B
and 3-oxo-katononic acids) were isolated. A 2,3-seco-isobriononico acid biosynthesis from
multiflorenol proposal was presented. The family chemosystematics has been discussed. / A família Burseraceae compreende aproximadamente 700 espécies distribuídas em 19
gêneros, sendo que várias destas espécies não apresentam estudos fitoquímicos. Com interesse
em descrever a composição química, avaliar a atividade citotóxica e isolar substâncias de
interesse químico e citotóxico, o trabalho foi dividido em três partes:
determinação do perfil químico dos extratos em hexano; avaliação da citotoxicidade de
extratos das oleorresinas contra as linhagens HCT-8 (cólon), MDA/MB-435 (melanoma) e
SF-295 (glioblastoma); e isolamento de substâncias presentes nas oleorresinas. As substâncias
isoladas foram identificadas pelas técnicas de espectrometria de massas (CG-EM e EMCIESI)
e ressonância magnética nuclear (RMN). No perfil dos compostos voláteis observou-se
que dentre os monoterpenos, o p-cimeno foi detectado mais vezes, em 11 das 23 espécies
avaliadas. A maior concentração deste composto foi observada em Protium apiculatum
(2,4%), contudo o componente majoritário nesta espécie é o α-pineno (5,1%). Dentre os
sesquiterpenos o componente que apresentou maior concentração foi o junenol, em P. cf.
rubrum (23,9%) e P. cf. ferrugineum (11,3%) sendo isolado e elucidado. As amostras com
perfil sesquiterpênico mais complexo foram P. tenuifolum e Tetragastris panamensis, com
detecção em comum de sesquiterpenos das séries bisabolano, cadinano, cubebano,
eudesmano, guaiano e muurulano. As avaliações dos cromatogramas de íons totais
demonstraram a presença dos α- e β-amirina em todas as amostras, confirmando a presença
destes triterpenos como marcadores desta família. Em P. cf. ferrugineum , observou-se a
ausência de α- e β-amirona, o que diferenciou esta espécie das demais amostras. Dentre os
triterpenos, foram detectados o glutinol (primeira descrição nos gêneros estudados) e o
multiflorenol (primeira descrição na família). A análise quimiométrica resultou em cinco
agrupamentos distintos (C-1 a C-5), onde o C-1 apresentou alta concentração de
α- e β-amirona e ausência de breina e maniladiol; o C-2, com espécies potencialmente
produtoras de novos triterpenos e de compostos voláteis; o C-3 com concentrações médias
entre as variáveis analisadas; o C-4 com concentração elevada de breina e maniladiol; e o C-5,
das espécies com alta concentração de α- e β-amirina. Os ensaios de citotoxicidade
demonstraram que dois extratos em hexano (P. cf. rubrum e Trattinnickia peruviana -
HrTPE) apresentaram inibição contra as linhagens de células tumorais HCT-8 (93,08 % para
ambas as espécies) e SF-295 (93,46 e 86,34%, respectivamente). Nos extratos em acetato de
etila foram observadas inibições por P. giganteum var giganteum e Trattinnickia glaziovii
contra as linhagens HCT-8 (88,7 e 92,9%, respectivamente) e MDAM B-435 (97,8 e 96,2%,
respectivamente). HrTPE foi submetido a fracionamento, sendo isolado o β-amiradienol. Do
extrato em acetato de etila de P. paniculatum var. modestum foram isolados os triterpenos
breina e maniladiol em mistura binária, o ácido 3-hidroxitirucalla-8,24-dieno-21-óico puro e
em mistura binária com 3-hidroxitirucalla-7,24-dieno-21-óico. No extrato em acetato de etila
de P. bahianum foram isolados os ácidos ursólico e oleanólico. Do extrato em acetato de etila
de Tetragastris panamensis foram isolados um triterpeno inédito (ácido 3-oxo- triptocálico B)
e dois triterpenos descritos pela primeira vez na família Burseraceae (ácidos triptocálico B e
3-oxo-katononico). Uma proposta de biossíntese do ácido 2,3-seco-isobrionônico a partir do
multiflorenol foi apresentada. A quimiossistemática da família foi discutida.
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Die Chemilumineszenz - Ihre Anwendung in der Konservierungsforschung bei der Untersuchung der Stabilität eines Triterpen-NaturharzesBuder, Andreas 15 March 2024 (has links)
In der Konservierungsforschung werden unterschiedlichste Materialien analysiert und auf ihre Stabilität hin geprüft, um gezielte Konservierungs- oder Restaurierungsmassnahmen durchzuführen und deren Nachhaltigkeit besser einschätzen zu können.
Die Chemilumineszenz - im Folgenden kurz CL - ist ein Phänomen, bei dem ein Elektron aus einem energetisch höher gelegenen Orbital in einen tiefer liegenden Zustand relaxiert und dabei seine Energie in Form von Photonen abgibt. Der angeregte Zustand wird durch eine chemische Reaktion verursacht.
Dieser Vorgang ist sehr spezifisch und tritt u.a. bei Oxidationsreaktionen auf. Durch Rekombination zweier Peroxide wird z.B. eine angeregte Carbonylverbindung erzeugt, die ihre Energie als Licht emittiert.
Dieser Zusammenhang zwischen der Oxidation organischer Substanzen und die Emission von Photonen bedingt die hier zentral gestellte Frage, ob die Chemilumineszenz als Methode zur Charakterisierung von Materialien, die in der Konservierungsforschung relevant sind, eingesetzt werden kann.
Innerhalb einer Forschungskooperation zwischen Departementen der Berner Fachhochschule BFH konnte ein Chemilumineszenz-Messgerät konstruiert, modifiziert und für diese Arbeit eingesetzt werden.
In der Arbeit wurde ein standardisiertes Messverfahren an verschiedenen Substanzen, wie z.B. Adamantylidenadamantan-1.2-dioxetan geprüft und die verschiedenen Einflüsse auf das Chemilumineszenz-Signal untersucht. Dabei konnten für das Messprinzip wichtige Daten, wie z.B. Präzision, Nachweis- und Bestimmungsgrenze erhoben werden.
Anhand der Stabilität von Dammar, einem Triterpen-Naturharz, konnte das Verfahren innerhalb der Arbeit, an einem komplexen Beispiel aus der Konservierungsforschung experimentell erprobt werden. Dabei wurden publizierte Resultate zum Oxidationsverhalten von Dammarharz teilweise verifiziert. Durch das spezifische Signal konnten die thermisch initiierten Reaktionen bei inerten und oxidativen Gas-Atmosphären dokumentiert werden. Die Ergebnisse wurden mit etablierten Methoden, wie z.B. DSC, TGA und ESR- Spektroskopie verglichen und Konsistenzen zu den Signalen erfasst.
Der in der Literatur diskutierte Einfluss von Stabilisatoren auf Dammarharz-Filme wurde an ungealterten und künstlich gealterten Proben mit der Chemilumineszenz untersucht. Dabei konnten ebenfalls in der Literatur empfohlene Formulierungen und Wirkungen bestimmter synergetischer Mischungen nachgewiesen und bestätigt werden.
Aus den ermittelten Daten der CL-Messungen liessen sich in einem Ausblick kinetische Berechnungen zu Aktivierungsparametern erstellen. Die ermittelten Parameter wurden zur Prognose von Reaktionsverläufen bei unterschiedlich simulierten Temperaturprofilen genutzt und machten eine Vorhersage zur Lebensdauer der Materialien möglich.
Neben der hohen Leistungsfähigkeit der Methode zeigte sich v.a. das hohe Potential der ermittelten Messdaten, v.a. in Bezug auf die Anwendung in der Modellfreien Kinetik.
Neben diesen Möglichkeiten wurden aber auch die Grenzen der Methode aufgezeigt. Diese sind einerseits durch die Besonderheit des Signals gegeben, welches mechanistisch bis heute noch nicht vollständig aufgeklärt ist, andererseits liegen sie bei der Weiterverarbeitung der Messdaten durch thermokinetische Software. Hier wird deutlich, dass die Qualität der Berechnungen zu Reaktionsverläufen nur so gut ist, wie die zuvor erhobenen Daten und, dass erstellte Prognosen zur Stabilität eines Materials lediglich eine Vorstellung vermitteln können. / During conservation studies different materials are analysed and tested for their solidity in order to be able to carry out precise conservation and restoration measures and to be able to assess their sustainability.
Chemiluminescence is a phenomenon in which an electron is relaxed from an energetically higher orbital into a lower situated condition while simultaneously releasing energy in the shape of photons. As a consequence the stimulated state is caused by a chemical reaction. This process is very specific and occurs during an oxidation reaction among other things. Through the recombination of two peroxides for example a stimulated carbonyl compound is generated which emits its energy as light.
This connection between the oxidation of organic substances and the emission of photons determines the main question, whether chemiluminescence can be used as a method for characterisation of materials which are relevant to the research of conservation.
As a result of a research project between departments of the Bern University of Applied Sciences BFH it was possible to construct a chemiluminescence measuring device and modify it in a way that it could be used for this work.
Within this experiment a standardised method of measurement was tested on different substances, for example adamantylidenadamantan-1.2-dioxetan, and the different impacts on the chemiluminescence-signal investigated. Through this process important facts were determined for the concept of measurement, for example precision, proof- and definition perimeters.
Based on the solidity of dammar, a triterpene resin, the method could be experimentally verified within the test using a complex example from conservation research. Within that process published results about the oxidation properties of dammar resin were verified. Due to the specific signal, the thermally initiated responses in inert as well as oxidative gas atmospheres could be documented. The results were compared with established methods like DSC, TGA and ESR spectroscopy and the consistencies to the signals logged.
The already much discussed influence of stabilisers on dammar resin was tested on nonaged and artificially aged specimens using chemiluminescence. Through these previously suggested formulations, effects of certain synergistic composites were detected and confirmed.
Using the data from the chemiluminescence measurements kinetic calculations about activation parameters were compiled. The identified parameters were used for the prognosis of the course of reactions during differently simulated temperature profiles, making a prediction of the materials’ life span possible.
Through these results not only the high performance ability of the method became apparent but also the potential of the determined measurement data, mainly in connection with the application within the model-free kinetic.
However, alongside these possibilities limitations of the method were revealed. These are partly caused by the characteristics of the signal which has yet to be mechanistically fully clarified. Simultaneously, further processing of the measurement data via thermokinetic software makes clear that the quality of the calculations of the reaction process is only as good as the quality of the initial data. This suggests the prognoses about the stability of the material only conveys a concept of their qualities.
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