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Dissertations / Theses on the topic 'Pharmacognosy'
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Lindholm, Petra. "Cytotoxic Compounds of Plant Origin – Biological and Chemical Diversity." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5728.
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Grechana, O. V., O. O. Saliy, A. G. Serbin, and L. A. Fukleva. "The pharmacognosy investigation of associated coumarins Lupinus luteus L." Thesis, Technical University in Zvolen, 2019. https://er.knutd.edu.ua/handle/123456789/15141.
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The genus Lupinus (Lupinus L.) is attributed to the legumes family (Fabaceae L.). About 1000 herbaceous, semi-bush and shrub, annual, winter and perennial lupines are described. In this paper we focuses on the issue of pharmacognostical study of plants is widely used in animal breeding, is the active substance in the manufacture of dietary supplements - the yellow lupine (Fabaceae). Harvested grass were analyzed after acid hydrolysis. Gas-liquid chromatography was first performed with mass spectrometric detection of hydrolysed raw material of Lupinus luteus L., where 56 compounds were found, of which 35 components were identified. After hydrolysis, the raw material of L. luteus L. contained a number of biologically active substances – fatty acids, alcohols, ketones etc. Two components from the class of true coumarins were identified: coumarin (16.4 mg%) and 6–methylcoumarin (2.7 mg%).
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Simmons, Colleen B. "Pharmacognosy and micropropagation of feverfew, Tanacetum parthenium, L, Schultz Bip." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ33273.pdf.
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Blondeau, Sylvain. "Développement d'une plateforme informatique hétérogène appliquée à la pharmacognosie." Thesis, Orléans, 2011. http://www.theses.fr/2011ORLE2004.
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La pharmacognosie, science multidisciplinaire étudiant les produits naturels, n'a eu de cesse de s'adapter et d'évoluer parallèlement aux autres disciplines, en particulier les techniques d'analyse chimique et les technologies de l'information. De nouvelles approches complémentaires, comme la pharmacognosie inverse allant des molécules vers les organismes sources, un cheminement en sens inverse de la pharmacognosie, ont été développées. Les données nécessaires à ces études n'ont jamais été aussi nombreuses et hétérogènes. Molécules, activités, cibles, organismes sources et leurs usages traditionnels, sont autant d'informations essentielles à la pharmacognosie. Le but de cette thèse a été de développer une plateforme informatique, regroupant toutes ces informations diverses au sein d'une vaste base de données, accompagnée d'une interface web dédiée et d'outils de chémoinformatique et de fouille de données. Parallèlement, un enrichissement constant de cette base a été réalisé. Cette plateforme permet de rechercher et de consulter les informations, mais également de les croiser afin d'en faire émerger de nouvelles connaissances. Réellement optimisée pour la pharmacognosie, elle simplifie et améliore l'étude des produits naturels en permettant une approche sur de multiples niveaux (ethnopharmacologie, botanique, chimie), offrant de nouvelles possibilités d'interaction entre les données de ces différents domaines comme l'organism hopping (sauts entre organismes), une approche originale de comparaison des organismes selon leurs profils chimiques<br>Pharmacognosy, a multidisciplinary science which studies natural products, has greatly evolved in parallel with other disciplines particularly analytical chemistry and information technologies. New complementary approaches like reverse pharmacognosy, from molecules to source organisms (in contrary of pharmacognosy), have been developed. Data necessary for these studies are overwhelming and heterogeneous. Molecules, activities, targets, organisms, traditional uses, are some of essential information for pharmacognosy. The main goal of this thesis was to develop an information platform, including a large database, to collect the diverse data, along with a specific web interface and also mining and cheminformatics tools. A constant enrichment of this database has also been realized. This platform allows to query and browse data, but also to cross them in order to discover new knowledge. Truely optimised for pharmacognosy, it makes easier and enhances the study of natural products, due to a multi-level approach (ethnopharmacology, botany, chemistry). It offers new possibilities of interaction between data from different domains, such as organism hopping, a new concept of organism comparisons according to their chemical profiles
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Rosén, Josefin. "ChemGPS-NP and the Exploration of Biologically Relevant Chemical Space." Doctoral thesis, Uppsala universitet, Institutionen för läkemedelskemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-89364.
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Chemical space is basically infinite, and comprises all molecules that could possibly exist. Intelligent ways to efficiently navigate through chemical space and to select promising compounds in drug discovery are important tasks, and the focus of this thesis. In this work a new model for chemical space navigation, ChemGPS-NP, was developed. This model is based on a methodology where a global chemical space map is defined through principal component analysis of physico-chemical properties of a reference set of compounds. Through interpolation from the reference set, positions of novel compounds can be defined on this map and interpreted as chemical properties. ChemGPS-NP was demonstrated to be able to chart the entire biologically relevant chemical space, including both drug-like and natural compounds. This is an important improvement considering the present interest in natural products (NPs) in the pharmaceutical industry, as well as the track record of NPs to serve as basis for more than 50% of all marketed drugs. ChemGPS-NP proved able to handle and process large data sets, to aid in efficient selection of test objects, and to extract useful information from the results of high-throughput screening campaigns. Using ChemGPS-NP, it was shown that NPs occupy unique regions of chemical property space in comparison to drug-like compounds, and a number of features distinguishing NPs from medicinal chemistry compounds were identified. ChemGPS-NP was also shown to be able to reliably predict mode of action of anticancer agents based on chemical structure, a finding that has potential to improve cancer research efficiency. Applying a property based similarity search based on calculated eight dimensional Euclidean distances from ChemGPS-NP rendered a tool to identify NP inspired potential leads for drug discovery. Furthermore, ChemGPS-NPWeb, an online version of ChemGPS-NP, was developed, which provides scientists with open access to the tool via http://chemgps.bmc.uu.se/.
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Barnes, Joanne. "An examination of the role of the pharmacist in the safe, effective and appropriate use of complementary medicines." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249582.
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Osorio, Adriana de Carvalho. "Aspectos farmacognósticos de Chamaecrista nictans subsp. patellaria var. ramosa Irwin & Barneby." Universidade de São Paulo, 1995. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-13012015-102331/.
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Não consta resumo na publicação.<br>Chamaecrista nictans subsp.patellaria var. ramosa Irwin & Barneby (Cassia Patellaria Dc), popularly know as \"peninha\", \"mata-pasto\", \"falsa-sensitiva\" e \"falsa-dormideira\", is Brazilian plant of the family Leguminosae. It is considered a garden and plantation weed, but in folk medicine is used for kidney problems and renal calculi. In order to identify their plant as a drug the morfology, histology, phytochemical screening, caracterization of fluid extract and plant powder were studied. In phytochemical screening the presence of flavonoid, saponins, steroids, tanins and coumarins was detected. A pharmacological assay was also carried out to test effect of chronic treatment with fluid extract in the experimental urolithiases in rats, through the development of calculi by surgical insertion of a foreign body their bladder. In rats, the results showed that chronic treatment with the same dosage of that used in folk medicine had no influence on the stones formed.
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Röpke, Cristina Dislich. "Avaliação da atividade antioxidante de Pothomorphe umbellata L. Miq na pele." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-24112015-182714/.
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O objetivo deste trabalho foi estudar a atividade antioxidante de um extrato padronizado da raiz de Pothomorphe umbellata L. Miq, incorporado em diadermina (creme óleo em água - O/A), sobre a pele de camundongos Hairless e avaliar esta atividade antioxidante em comparação à atividade antioxidante do α-tocoferol, incorporado na mesma base. A peroxidação lipídica foi avaliada como medida de TBARS e de quimiluminescência. Animais tratados com o extrato de Pothomorphe umbellata demonstraram um decréscimo significativo nos parâmetros de peroxidação lipídica, em concentrações de até 0,1% p/p de 4-nerolidilcatecol (o que equivale a uma concentração de 4% p/p de extrato) incorporado na diadermina. Em nosso modelo o decréscimo significativo destes indicadores, nos animais tratados com α-tocoferol, só foi observado em concentrações superiores a 5%. Os resultados indicam uma potente atividade antioxidante do extrato da raiz de Pothomorphe umbellata, sugerindo sua aplicação em formulações cosméticas.<br>Antioxidants may play a significant role in ameliorating or preventing oxidative damage to skin. In this work antioxidant activity of P. umbellata root extract, with known concentration of 4-nerolidylcathecol, incorporated to a hydrophilic ointment in different concentrations, was evaluated on skin of Hairless mice. This antioxidant activity was compared with that of different concentrations of α-tocopherol (Sigma) incorporated in the same vehicle. Lipid peroxidation of skin homogenates was evaluated as thiobarbituric acid reactants (TBARS) and chemiluminescense (CL). Animals treated with P. umbellata root extract showed a decrease up to 90% in the lipid peroxidation parameters, for concentrations higher than 0.1%. Our model demonstrated a significant decrease in TBARS an CL only for higher concentrations of α-tocopherol (5 and 10% w/w). The results indicate a potent antioxidant activity of the Pothomorphe umbellata root extract, suggesting its application in cosmetic formulations.
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Huss, Ulrika. "Studies on the Effects of Plant and Food Constituents on Cyclooxygenase-2 : Aspects in Inflammation and Cancer." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3582.
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Sousa, Carla Sara Ferreira de. "PERFIL METABÓLICO E POTENCIAL ANTIOXIDANTE DE BRASSICA OLERACEA." Doctoral thesis, Faculdade de Farmácia da Universidade do Porto, 2008. http://hdl.handle.net/10216/22549.
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Sousa, Carla Sara Ferreira de. "PERFIL METABÓLICO E POTENCIAL ANTIOXIDANTE DE BRASSICA OLERACEA." Tese, Faculdade de Farmácia da Universidade do Porto, 2008. http://hdl.handle.net/10216/22549.
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Paul, Debashri. "Pharmacognosy of Rauvolsfia serpentina (L) Benth ex Kruz in the Ecological condition of Darjeeling district of West Bengal." Thesis, University of North Bengal, 2001. http://hdl.handle.net/123456789/892.
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Svangård, Erika. "Cytotoxic cyclotides : structure, activity, and mode of action /." Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6028.
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Scicluna-Spiteri, Anthony. "Drimia maritima (L) stearn in Malta : the growth, quality and commercial potential of Maltese squill, Drimia maritima." Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236486.
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Osborne, S. J. "Phytochemical and anatomical investigations in the genera Acronychia and Maclurodendron." Thesis, University of Sunderland, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234871.
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Wake, George. "Cholinergic phytochemicals from medicinal herbs : potential sources of novel dementia treatments." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366551.
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Alshammari, Saud. "Proteomic Evaluation and Cytotoxicity of Red Maple (Acer rubrum) Leaves." Chapman University Digital Commons, 2019. https://digitalcommons.chapman.edu/pharmaceutical_sciences_theses/4.
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Red maple (Acer rubrum), also known as swamp, water or soft maple, is endemic to eastern and central North America and was widely used as traditional medicine by the first peoples. Commercially, its well-known products include maple syrup and high-quality lumber. The potential medicinal benefits of phenolic compounds extracted from the red maple plant, such as glucitol-core containing gallotannins, include antioxidant, and antiglycation effects as well as their importance in cosmetic applications. Plant-derived proteins and peptides are important biomolecules; however to date, there is no published data on the identification of proteins/peptides from red maple leaves. Therefore, the present study focuses on the activity guided purification of proteins from red maple leaves collected in spring and fall seasons. In addition, the focus of this project was in the evaluation of maple leaves employing bottom-up proteomics and De Novo protein profiling by PEAKS Studio-X and Gene Ontology Bioinformatics. The red maple leaves were grounded, defatted in hexane and proteins extracted in 25 mM sodium phosphate buffer pH 6.5. The extracted crude proteins were recovered by precipitation in 80% ammonium sulfate. The first-dimensional chromatography of crude extracted proteins was performed on a gel filtration column (HiLoad 16/600 Superdex200). The separation of crude extract and the partially purified gel filtration fraction was conducted by reversed-phase HPLC. The crude and eluted fractions were analyzed by SDS-PAGE gel electrophoresis. The extract was screened for cytotoxicity activity on Michigan Cancer Foundation-7 breast cancer (MCF-7), M.D. Anderson Metastasis Breast (MDA-MB-231) cancer cell lines and anti-inflammatory activity on murine macrophage (RAW 264.7) cell line from American Type Culture Collection (ATCC). The drug Doxorubicin was used as a positive control whereas untreated cells as a negative control in these experiments Preliminary data revealed that active protein fractions were eluted at two different regions of gel filtration chromatography both in spring and fall leaves. Bottom-up proteomics of crude and active fractions by PEAKS Studio-X and MASCOT bioinformatics database identified over 54 proteins. The Gene Ontology Annotation classified these proteins involved in the biological processing, cellular compartment, and molecular functions.
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Case, Olivia Hildegard. "An assessment of medicinal hemp plant extracts as natural antibiotic and immune modulation phytotherapies." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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This study aimed to evaluate the antimicrobial efficacy of medicinal hemp plant extracts to determine the antibacterial effects of indigenous Sansevieria species and exotic Cannabis sativa phytotherapy varieties. This study also assessed whether aqueous o
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Ringbom, Therese. "Bioassay Development for Identification of Cyclooxygenase-2 Inhibitors of Natural Origin." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2002. http://publications.uu.se/theses/91-554-5276-0/.
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Gonzalez, Fabiana Gaspar. "Estudo farmacognóstico e farmacológico de Caesalpinia ferrea Martius." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-09042014-140127/.
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Caesalpinia férrea Martius, popularmente conhecida como pau-ferro e jucá, é utilizada na medicina tradicional para o tratamento de problemas hepáticos, respiratórios e, em especial, para distúrbios gastrintestinais e como cicatrizante. Deste modo, os objetivos do presente trabalho visaram avaliar os extratos brutos liofilizados de folha (EBLF) e caule (EBLC) quanto a caracterização botânica, o estudo químico e farmacológico, direcionando principalmente, às ações antiúlcera, antioxidante e cicatrizante, e toxicidade destes órgãos vegetais de C. ferrea. A triagem fitoquímica foi realizada com a droga vegetal constituída de folha (DF) e de caule (DC), bem como com os seus EBLF e EBLC. Os métodos empregados foram preconizados por Farnsworth (1966) e Matos (1988) onde foram pesquisados os seguintes compostos: flavonóides, glicósidos cardiotônicos, saponinas, antraderivados, alcalóides, cumarinas, taninos e óleo essencial. Além disso, foi realizada a quantificação de taninos e flavonóides segundo a metodologia proposta na Farmacopéia Européia (2001) e na Farmacopéia Brasileira (2003), respectivamente. Para a avaliação da Toxicidade de C. ferrea foram realizadas a Toxicidade Aguda de ambos os órgãos vegetais, a DL50 do EBLF e a Toxicidade subcrônica do EBLF e EBLC, todos os modelos seguiram a metodologia de Brito (1994). Para análise da atividade antiulcerogênica da espécie em estudo foi realizado o teste da indução de lesão gástrica aguda por etanol/HCI e lesão subcrônica por ácido acético. Grupos Tratados receberam EBLF ou EBLC ou frações ou extratos enriquecidos em flavonóides, Grupo Controle água ou tween 80 e Grupo de Referência Misoprostol ou Cimetidina. Três parâmetros foram avaliados neste modelo: Área Total de Lesão (ATL) , Área Relativa de Lesão (ARL) e índice de Lesão Ulcerativa (ILU). A atividade antioxidante \"in vitro\" foi medida através da inibição da autoxidação de homogenato de cérebro de Ratos (Stocks et aI., 1974). Os extratos foram solubilizados em etanol 70% e as diluições (0.05-0.003mg/mL) foram efetuadas em etanol 35%. O etanol 35% foi utilizado como controle. E na avaliação da Atividade Cicatrizante, os animais (ratos) sofreram uma incisão na região dorsal com auxílio de punch. Os Grupos Tratados receberam diariamente 1 mL de EBLF ou EBLC, solubilizados a 15% em água, e o Grupo Controle água destilada na mesma proporção por um período de 14 dias. Na triagem fitoquímica foram detectados para ambos os extratos, flavonóides, taninos, além de antraderivados e cumarinas nas Folhas. A porcentagem encontrada de Taninos na DF foi de 7.13% e no EBLF de 23.95% e na DC foi de 2.26% e no EBLC de 11.77%. Já a quantificação de flavonóides foi de 0.0095% na DF, 0.026% no EBLF, 0.00014% na DC e de 0.0017% no EBLC. No teste de toxicidade aguda, somente os animais que receberam EBLF apresentaram alterações comportamentais a partir dos primeiros tempos de observação e morte de 3 animais machos e 2 fêmeas (n=5/sexo). Dessa forma, a DL50 encontrada para este extrato vegetal foi de 5471.64 mg/Kg para as fêmeas e de 3112.94 mg/Kg para os machos. Na Toxicidade subcrônica, apenas os animais fêmeas que receberam EBLC (800 mg/Kg) apresentaram uma diferença significativa, em relação ao grupo controle, quanto ao peso do rim, porém não foi encontrada nenhuma alteração histológica neste órgão. EBLF e EBLC apresentaram significativa atividade antiulcerogênica no modelo de lesão gástrica aguda dentro dos parâmetros avaliados. O EBLC reduziu em 37% a ARL. Já o EBLF foi tão ativo como o Misoprostol reduzindo em 95%, 81% e 63% a ATL, a ARL e o ILU, respectivamente contra 92%, 70% e 59% do fármaco de referência. Porém, as frações e os extratos enriquecidos em flavonóides obtidos de ambos os extratos brutos liofilizados não apresentaram atividade antiulcerogênica em nenhum dos 3 parâmetros. Esses mesmos resultados foram obtidos no modelo de lesão gástrica subcrônica para ambos os extratos vegetais. Os EBLF e EBLC de C. ferrea promoveram uma atividade antioxidante de 94% e 84%, respectivamente, na concentração de 0.8196 µg/mL, e um Q 1/2de 0.2331 (Folha) e 0.5061 (Caule) µg/mL. Na avaliação da atividade cicatrizante de ambos os extratos vegetais, não foi encontrada diferença significativa entre os Grupos Tratados e Controle. No laudo histológico não se observou nenhum sinal de cicatrização tecidual. Apesar de C. ferrea ser utilizada pela população como cicatrizante, não foi possível confirmar tal atividade nas folhas e nos caules desta espécie.<br>Caesalpinia ferrea Martius , populary, known as iron-wood or juca, is utilized in traditional medicine in the treatment of both hepatic and respiratory problems and, in special, for gastrointestinals disturbances and eventual healing. The objective of the present work is to evaluate the leiophyllized brute extracts of the leaf (lBEl) and the stem (lBES), the botanic caracterization, the chemical and pharmacological studies, focuzing principally, the antiulcer and healing action, and also the toxicity of these vegetable organs of C. ferrea. The phytochemical was ma de with the drug of the leaf (DL) and of the stem (DS)- LaEL and lBES. The method was precognized by Famsworth (1966) e Matos (1988) where doing research of: flavonoids, cardiotonic glicosids, saponins, antraderivates, alkaloids, coumarins, tannins and essential oi!. Beyond that, the quantification of tannins and flavonoids according to the metodology proposed in European Pharmacopeia (2001) and Brazilian Pharmacopeia (2003) were also undertaken, respectively. For the evaluation of the C. ferrea toxicity, the acute toxicity of both vegetable organs, the DL50 of LBEL and the subcronical toxicity of LBEL and LBES, were analyzed following the metodology of Brito (1994).The test of induction of acute gastric lesion for ethanol/HCI was used for antiulcerogenic activity analysis of the species studied. Treated Groups received LBEL or LBES or fractions or extracts enrich in flavonoids, Controls Groups water or tween 80 and misoprostol Reference Group. Three parameters were evaluated considering: Total Area of Lesion (TAL), Relative Area of Lesion (RAL) and Rate of Ulcerative Lesion (RUL). And for evaluation of subcronic gastric lesion by acetic acid 30%, the Treated Group received LBEL or LBES, Control Group water and cimetidine Reference Group. The ulcerative lesions were evaluated only in 2 parameters: RAL and RUL. An antioxidant activity \"in vitro\" was measured through inibition of antioxidation of homogenate of rat brain (Stocks et aI., 1974). The extracts were solubilized in ethanol 70% and dilutions (0.05-0.003mg/mL) were performed in ethanol 35%. The ethanol 35% was utilized like control. And for evaluation of healing activity, the animals (rats) suffered na incision in the dorsal region with a punch aid. The Treated Groups received daily 1mL of LBEL or LBES, solubilized by 15% in water, and Control Group distilled in the same proportion during a 14 day period. In phytochemical were detected for both extacts, flavonoids, tannins., beyond antradderivate and coumarins in leaves. The percentages of tannins found were 7.13% in DL, 23.95% in LBEL, 2.26% in OS and 11.77% in LBES. The quantification of flavonoids was 0.0095% in DL, 0.026% in LBEL, 0.00014% in DS and 0.0017% in LBES. During the acute toxicity test, it was observed a behaviour alteration among animais that received LBEL up tp the first time of observation and death pof 3 males and 2 females. The DL50 found to this vegetable extract was 5471.64 mg/Kg for the females and 3112.94 mg/Kg for the males. In subronic toxicity, only the females receiving LBES (800mg/Kg) presented a significant difference, according to the Control Group, as much as the weight of a kidney. However, no histologic alteration in this organ was found. LBEL and LBES presented antiulcerogenic significant activity in acute gstric lesions, based on the parameters evaluated. The LBES was reduced to 37% in RAL. The LBEL was so active as the misoprostol, being reducid to 95%,81% and 63% TAL, RAL and the RUL, respectively against 92%, 70% and 59% of pharmaco of reference. Nevertheless, nor the fractions nor the flavonoids enriched extracts obtained from both leiophyllized brute extracts showed antiulcerogenic activity at the 3 studied parameters. Up to the present time, in model subcronic gastric lesion, none of both vegetable extracts in question has showed active similar to TAL, RAL and RUL in relation to the Control Group. The LBEL and LBES of C. ferrea promoved an antioxidant activity of 93,56% and 84,38%, respectively, in concentration of de 0.8196 µg/mL, and a Q1/2 of 0.2331 (leaf) and 0.5061 (Stem) µg/mL. Conceming the healing activity evaluation of both vegetable extracts, no significant differences between Treats and Control Groups were found. Also in histologic award, no sign of tecidual cicatrization was observed. In spite of the fact that C. ferrea has been utilized by the population as cicatrizant, no clear evidence of its leaves and stems healing activity has been confirmed.
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Tang, Wei. "Compounds interacting with the PDZ2 domain of PSD-95 : identification in and isolation from a traditional Chinese medicinal plant /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202002%20TANG.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.<br>Includes bibliographical references (leaves 72-82). Also available in electronic version. Access restricted to campus users.
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Yonjan, Bidyawati. "Studies on growth and development of Emetine yielding Ipecac, Cephaelis ipecacuanha (Brot.) A Richard, with special reference to temperature stress and pharmacognosy." Thesis, University of North Bengal, 1988. http://hdl.handle.net/123456789/924.
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Larsson, Sonny. "Mistletoes and Thionins : as Selection Models in Natural Products Drug Discovery." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7705.
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Ribeiro, Bárbara Andreia Pinto Barbosa de Bessa. "Análise metabólica e capacidade antioxidante de espécies comestíveis de cogumelos selvagens." Doctoral thesis, Faculdade de Farmácia da Universidade do Porto, 2010. http://hdl.handle.net/10216/63811.
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Fernandes, Maria de Fátima Gomes. "Duo Ecológico Pieris brassicae/Brassica oleracea: Perfil Metabolómico e actividade biológica." Doctoral thesis, Faculdade de Farmácia da Universidade do Porto, 2010. http://hdl.handle.net/10216/63800.
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Sterby, Mia. "Dissecting the Structure-Activity Relationship of Hairpinin, a Plant Derived Antimicrobial Peptide." Thesis, Uppsala universitet, Avdelningen för farmakognosi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-226582.
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Antibiotic resistance is a growing health issue that necessitates development of alternative drugs with antimicrobial properties. Antimicrobial peptides are a promising group of compounds in this respect and are used by all varieties of living organisms to defend against invading or competing organisms. Hairpinin is an antimicrobial peptide isolated from Echinochloa crus-galli that has previously been found to have antifungal activity. In this study, truncated variants of hairpinin were synthesized and their antifungal activity tested against Candida albicans, Aspergillus fumigatus, and Saccharomyces cerevisiae to identify the minimum structural element of hairpinin required for maintained activity. Hairpinin was active against all three fungi with a minimum inhibitory concentration ranging between 0.6 μM - 5 μM depending on strain and growth media. Two truncated versions were synthesized in this study by solid-phase peptide synthesis, also resulting in a dimer of one of the derivatives, and their antifungal activity was assessed together with four other truncated peptides previously synthesized. The findings indicated that hairpinins C-terminal end together with an inflexible central part stabilized by at least one disulfide bond was vital for activity. The mechanism of action in which hairpinin inhibits fungi was examined by liposome leakage assay of Escherichia coli and Saccharomyces cerevisiae model membranes. It was concluded that the mechanism of action did not involve membrane disruption, a common mechanism among similar antimicrobial peptides. Although hairpinin displayed potent antifungal activity, it was found to be proteolytically unstable in serum. To improve hairpinins value in pharmaceutical context stability has to be improved while preserving the important structural elements.
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Fernandes, Maria de Fátima Gomes. "Duo Ecológico Pieris brassicae/Brassica oleracea: Perfil Metabolómico e actividade biológica." Tese, Faculdade de Farmácia da Universidade do Porto, 2010. http://hdl.handle.net/10216/63800.
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Ribeiro, Bárbara Andreia Pinto Barbosa de Bessa. "Análise metabólica e capacidade antioxidante de espécies comestíveis de cogumelos selvagens." Tese, Faculdade de Farmácia da Universidade do Porto, 2010. http://hdl.handle.net/10216/63811.
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Steinborner, Simon Todd. "The observation of evolutionary trends in amphibians and the analysis of negative ion fragmentations in large peptide systems by mass spectrometry /." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phs819.pdf.
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Wong, Queenie Lai Lai. "Pharmacognostic studies on folk medicinal herb xihuangcao." HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/215.
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Xihuangcao is a folk medicinal herb used in southern China with three botanical origins: Isodon lophanthoides (IL), I. lophanthoides var. graciliflorus (ILG) and I. serra (IS). They are often used indiscriminately, numerous commercially available herbal products list Xihuangcao as an ingredient without listing the source. This situation has led to a growing concern about the differentiation and quality evaluation of Xihuangcao. To address this concern, a systematic study was conducted to identify the origin. The study is divided into five parts, which aimed to establish and apply the authentication methods of the origins. Four Isodon species were recorded in research papers as the plant sources. However, a new classification suggested in 2004 and two of the IL varieties were merged. In the ancient herbal documents, ILG was first recorded as the origin plant. IL was the major species in the ancient texts, IS was only listed as an additional sources in recent herbal references. The“yellow juices which proven to be the exudates of glandular scales was the key identification features recorded. Macroscopic and microscopic studies provided identification features of the three Isodon species. IL and ILG share very similar features, but IS can be easily distinguished. By morphological features, IL and ILG can be distinguished by the shape of leaves, which IL has a broader leaves than ILG; IS can be identified by its very bitter taste and broadly winged petioles. By microscopic features, IL and ILG have a tiny difference in the shape of epidermal cells of leaf, and IS can be recognized by small raphides of calcium oxalate. In the UPLC-MS fingerprinting and tissue-specific profiling, the chemical profiles the three species were revealed. The chemical profiles of IL and ILG were similar, while IS has its specific chemical profiles. Twenty-seven characteristic peaks were chosen and showed a good distinction of the three species. The tissue-specific profiling of leaves showed the diterpenoids of all the species were accumulated only in the glandular scales. Lipidomics study on IL, ILG and IS was also conducted. A total of 92 lipids were identified. The variation of lipid profiles of the three Isodon species was further quantified, the results showed that the contents of the lipids in the three Isodon species varied. Statistical analyses showed IS has distinctly different lipid profile, while that of IL and ILG are very similar. Finally, the methods of macroscopic microscopic authentication and UPLC-MS fingerprinting were applied in identifying the source species of commercial Xihuangcao products. Twenty-seven batches of Xihuangcao decoction pieces were identified, results showed ILG is the major source of the collected samples. The ingredients in eight Xihuangcao herbal tea bags were also identified. IS is the major species, and none of the samples match their labels. The study provided valuable information on the authentication and quality control of folk medicinal herb Xihuangcao. The work also provided fundamental information on further studies on the chemical constituents of IL and ILG, also and role of lipids in the production of bioactive diterpenoids in Isodon species
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Salehy, Surmaghy M. H. "The pharmacognosy of Diplotaenia cachrydifolia : Characterisation of the coumarins and volatile principles and the histology of D. cachrydifolia Boiss. (Apiaceae)." Thesis, University of Bradford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384260.
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Phun, Lien Hoang. "Innovative approaches to carbocyclic and heterocyclic compounds using strained carbocycles." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47542.
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Natural products and small molecules play a major role in drug development. However, using natural products as a source of medicine comes with many challenges, such as lack of natural abundance and difficulty in isolation. Consequently, synthetic organic chemistry is a solution in order to access these compounds in usable quantities. However, synthetic chemisty comes with its own challenges such as efficiency, chemoselectivity, stereoselectivity and enantioselectivity. Therefore, synthetic tools that addresses these challenges are required solve these limitations. This thesis discusses new methodologies using strained carbocycles (cyclopropanes and cyclopropenes) as the reactive subunit for the construction of different carbocyclic and heterocyclic compounds. The homo-Nazarov cyclization of alkenyl and heteroaryl cyclopropyl ketones was used in order to construct cyclohexenones, cyclohexenols, heteroaryl ring-fused cyclohexenones, dihydrofurans, furans and furanones in a mild and efficient manner. Benzofused heteroaromatic compounds were achieved via the Lewis acid-catalyzed cycloisomerization of cyclopropene-3,3-dicarbonyls and furan-3-carboxylates. These heteroaromatic compounds can be applied to medicinal chemistry and material science.
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Schell, Rebecca. "Sceletium tortuosum and Mesembrine: A Potential Alternative Treatment for Depression." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/scripps_theses/375.
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Major depressive disorder affects people’s productivity and ability to function in everyday life. The disorder can be attributed to neurochemical imbalances of various neurotransmitters including but not limited to serotonin, dopamine, and norepinephrine. Conventional pharmacological treatments have focused primarily on these three neurotransmitters, and have been shown to be effective in alleviating most of the major symptoms of depression. Although these treatments are effective with most patients, they are known to have adverse side effects, causing patients to seek alternative treatments. Sceletium tortuosum, a succulent plant found in the Cape region of South Africa, has been shown to have anxiolytic effects when used recreationally. Studies have confirmed the presence of a family of alkaloids mesembrines that are present within the plant and believed to be responsible for the calming effects. Pharmacological analyses have revealed that individual members of the alkaloid family act as either serotonin reuptake inhibitors (SRI) or phosphodiesterase-4 (PDE4) inhibitors. The current study seeks to elucidate the antidepressant properties of the mesembrine alkaloids in a mouse model of depression. Isolated alkaloids were administered at a low dose (10 mg/kg) and a high dose (80 mg/kg) to BALB/c mice in the forced swim test a rodent model of behavioral despair. This was compared with paroxetine (Paxil) (1 mg/kg), a selective serotonin reuptake inhibitor with proven antidepressant efficacy, and 0.9% saline. Each trial of the forced swim test was administered for six minutes and the duration of swimming and immobility was measured. In order to assess any locomotor effects of the drug treatments, an open field exploration test was also employed one week following the forced swim task. Results from the forced swim test revealed a statistically significant reduction in the duration of immobility (behavioral despair) between the low dose of alkaloids and saline. No significant effects in immobility were found across the other drug treatment conditions (high dose mesembrine, paroxetine, and saline). Further, none of the treatment groups showed statistically significant locomotor interference effects in the open field exploration test. We conclude that the mesembrine alkaloids present in Sceletium tortuosum have antidepressant properties and may represent a suitable alternative for the treatment of major depressive disorder.
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Wang, Xu. "The antihypertentive effect of aqueous extract O Africana leaves." Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1212_1257948405.
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<p>The incidence of cardiovascular diseases, including hypertension, is on the increase worldwide. Medicinal plants played an important role in the treatment of hypertension for centuries. Very few scientific studies have, however, been done to validate the use of these phytotherapies. O africana is on of the many phytotherapies that has been use indigenously for years to treat hypertension. The objectives of this study were to determine the most effective does of O africana aqueous extract which will reduce blood pressure<br>to determine whether chronic administration of O africana can be used to prevent and treat hypertension<br>to determine whether O africana exert its effects by modulation of the renin-angiotensin system.</p>
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Dias, Tais Garcia. "Estudo farmacognóstico de Porangaba (Cordia ecalyculata Vell. - Boraginaceae) e identificação de adulterações." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-18042017-163612/.
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Cordia ecalyculata Vell. (Boraginaceae), espécie medicinal vulgarmente conhecida como porangaba e chá-de-bugre, é utilizada popularmente como emagrecedor, diurético, para curar tosses catarrais e reumatismos além de ser usada no tratamento de úlceras externas em forma de banhos. No Brasil existe grande confusão com relação aos nomes populares das espécies medicinais, fato que motivou a realização do presente trabalho. A espécie estudada é confundida com outras espécies vegetais, particularmente com Casearia sylvestris Swartz (Flacourtiaceae), também conhecida pelos nomes de guaçatonga e erva-de-bugre. O estudo farmacobotânico de C. ecalyculata revelou estruturas papilosas na epiderme e células esclereificadas no parênquima cortical, que não haviam sido descritas anteriormente. Foram listadas as principais diferenças morfoanatômicas entre as folhas de C. sylvestris e C. ecalyculata. auxiliares na diagnose da droga vegetal comercializada. As amostras adquiridas no comércio como porangaba não apresentaram características de C. ecalyculata, mas sim, de C. sylvestris, como: duas a três camadas de parênquima paliçádico; cavidades secretoras; drusas e cristais prismáticos em abundância; estômatos paracíticos; células epidérmicas poligonais; ausência de litocistos e areia cristalina. Fotomicrografias ilustram o trabalho. A triagem fitoquímica do extrato hidroetanólico liofilizado (EHEL) de C. ecalyculata apresentou resultado positivo para taninos, flavonóides e saponinas. A análise cromatográfica permitiu verificar a presença de substância coincidente com a alantoína no extrato de C. ecalyculata, além de possibilitar o desenvolvimento do perfil cromatográfico, auxiliar na diferenciação de C. sylvestris. Os ensaios de quantificação de alantoína no EHEL foram realizados por meio de dois métodos espectrofotométricos, cujos valores encontrados foram 0,68% e 0,70% de alantoína. O EHEL não apresentou róxicidade no ensaio de toxicidade aguda, na dose de 5 g/kg de massa corpórea do animal, por via oral. O experimento de atividade antiúlcera do EHEL de C. ecalyculata não apresentou diferenças significativas entre os animais controle e tratados.<br>Cordia ecalyculata Vell. (Boraginaceae) is a medicinal species most known as porangaba and chá-de-bugre. It is commonly used as diuretic, weight controller, for phleem cough healing, rheumatism healing and also in baths for externai ulcers treatment. The present work aims at clarifying the popular names of medicinal species often misnamed in Brazil. For example, the species cited above has always been mistaken as Casearia sylvestris Swartz. (Flacourtiaceae), also known as guaçatonga and erva-de-bugre. The pharmacological-botanical study of C. ecalyculata revealed papillary structures on the epidermis and sclerenchymatous cells on the cortical parenchyma which had not yet been described in the literature. The main morphological-anatomical differences between the C. sylvestris and the C. ecalyculata leaves were listed. These differences have been of great help concerning the diagnosis of commercialized vegetal drug. The commercialized samples do not show the features of the C. ecalyculata, but the features of the C. sylvestris, such as: two or three palisade parenchyma layers; secretive cavities; plenty of druses and prismatic crystals; paracytic stomata; polygonal epidermical cells; absence of lythocysts and crystal-sand, as it can be seen in the illustrative photomicrographies. The phytochemical screening of the lyophilized hydroethanolical extract (EHEL) of the C. ecalyculata showed a positive outcome for tannins, flavonoids and saponins. The chromatographic analysis not only allowed the evaluation of the coincident substance with the allantoin in the C. ecalyculata extract, but also enable the development of its chromatographic aspect, what eventually helped to differenciate it from C. sylvestris. The quantification assays of allantoin in the EHEL extract of the C. ecalyculata were performed through two spectrophotometric methods and the values found were 0,68% and 0,70% of allantoin. The EHEL extract displayed no toxicity in the acute toxicity trial in the 5 g/kg oral dosage per animal body weight. The anti-ulcer assay of this extract showed no meaningful differences among the subject and the treated animais.
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Tietbohl, Luis Armando Candido. "Estudo químico e biológico da espécie vegetal Myrciaria floribunda (H.West ex Willd.) O. Berg." Niterói, 2017. https://app.uff.br/riuff/handle/1/3315.
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Tietbohl, Luis Armando Candido [Dissertação, 2014].pdf: 8958883 bytes, checksum: 41b0a4341bcfc24a0012440a901a42f7 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>A espécie Myrciaria floribunda (H.West ex Willd.) O. Berg., Myrtaceae, popularmente conhecida como camboim-amarelo, foi coletada no Parque Nacional da Restinga de Jurubatiba (RJ, Brasil). Esta espécie é rica em estruturas secretoras de óleo essencial. Neste trabalho, é descrita a análise da composição química dos óleos essenciais de folhas, caules e flores. O monoterpeno 1,8 cineol apresenta-se como componente majoritário nos óleos de folhas (38,4%) e flores (22,8%). No óleo de caules a substância majoritária foi o acetato de farnesila (19,9%). Além das substâncias já descritas para o óleo essencial de folhas desta espécie, foram identificadas pela primeira vez: α-pineno (0,4%), mirceno (0,7%), (Z)-β-ocimeno (0,8%), γ-terpineno (0,8%), acetato de geranilo (1,5%), γ-himachaleno (7,0%), valenceno (1,8%), δ-amorpheno (4,0%), zonareno (4,6%), selina-3.7(11)-dieno (3,8%), neo-intermedeol (0,8 %) e (2E, 6Z)-farnesol (1,4%). As análises dos óleos essenciais de caules e flores ainda não haviam sido descritas para esta espécie. Também foram isolados e identificados pela primeira vez na espécie o triterpeno ácido betulínico e o flavonoide miricetina 3-O-β-galactosídeo da fração acetato de etila de folhas. O óleo essencial de folhas foi avaliado quanto as atividades: anticolinesterásica, antimicrobiana e inseticida. Os óleos de folhas, flores e caules foram avaliados quanto a atividade anticolinesterásica, mostrando um IC50 de 1583 e 681 μg/mL para flores e folhas, respectivamente. O óleo de caules não apresentou atividade. O teste de susceptibilidade antimicrobiana do óleo essencial das folhas utilizando cepas de Staphylococcus aureus ATCC 29213, apresentou um CMI de 250 μg/mL. A atividade inseticida do óleo essencial das folhas foi avaliada frente aos fitófagos Oncopeltus fasciatus e Dysdercus peruvianus e os óleos essenciais das folhas e flores foram avaliados frente ao percevejo hematófago da espécie Rhodnius prolixus. Os tratamentos dos insetos com os óleos essenciais de M. floribunda induziram mortalidade, atraso no desenvolvimento e inibição de muda. Para avaliar a atividade hipoglicemiante e integridade do fêmur em ratos machos, foi utilizado o extrato aquoso das folhas de M. floribunda a uma concentração de 5 % (p/v), onde foi possível verificar ao final dos 42 dias de tratamento uma diferença significativa na glicemia e resultados similares para o fêmur. O grupo tratado apresentou resultados significativamente aumentados de colesterol, proteína total, fósforo, magnésio e aspartato aminotransferase, massa de fígado menor e massa dos rins maiores quando comparados com o grupo controle.<br>The species Myrciaria floribunda (H.West ex Willd.) O. Berg., Myrtaceae, popularly known as “camboim-amarelo”, was collected in the “Parque Nacional da Restinga de Jurubatiba” (RJ, Brazil). This species is rich in secretory structures essential oil. This work describes the analysis of the chemical composition of the essential oil of leaves, stems and flowers in that the monoterpene 1.8-cineole present as the major component in the oil leaves and flowers corresponding 38.4% 22.8%, respectively. Already at oil from stems the substance majority was farnesyl acetate (19.9%). In addition to the substances already described for the essential oil from leaves of the species were first identified the following substances : α-pinene (0.4%), myrcene (0.7%), (Z)-β-ocimene (0.8%), γ-terpinene (0.8%), geranyl acetate (1.5%), γ-himachalene (7.0%), valencene (1.8%), δ-amorphene (4.0%), zonarene (4.6%), 3.7-selina (11) -diene (3.8%), neo-intermedeol (0.8%) and (2E, 6Z)-farnesol (1.4%). The analysis of essential oils from stems and flowers had not yet been described. Were also isolated and identified for the first time in the kind triterpene betulinic acid and flavonoid myricetin 3-O-β-galactoside of ethyl acetate fraction of leaves. The essential oil from leaves was evaluated for activities: acetylcholinesterase, antimicrobial and insecticidal. The oils from leaves, flowers and stems were evaluated for anticholinesterase activity, showing an IC50 of 1583 and 681 mg/mL for flowers and leaves, respectively, and stems showed no activity. The antimicrobial susceptibility testing essential oil from leaves using Staphylococcus aureus ATCC 29213, filed an IMC 250 μg/mL. Insecticidal activity of the essential oil from the leaves was evaluated against phytophagous Oncopeltus fasciatus and Dysdercus peruvianus, and the essential oil from the leaves and flowers were evaluated against the Rhodnius prolixus. All treatments of insects with essential oils of M. floribunda induced mortality, developmental delay and inhibition of molting. To evaluate the hypoglycemic activity and femur health in male rats, were evaluated with the aqueous extract of leaves of M. floribunda at a concentration of 5%, which was verified at the end of the 42 days of treatment the infusion decreased the glycemia e maintenance results similar to the femur. Treated group apresented results significantly increased to cholesterol, total protein, phosphorus, magnesium and aspartate aminotransferase, mass minor liver and kidney mass was increased compared with the control group
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McErlean, Matthew Richard. "ACTINOMYCIN FAMILIAL DIVERSITY DRIVEN BY PHENOXAZINONE-CORE REACTIVITY." UKnowledge, 2019. https://uknowledge.uky.edu/pharmacy_etds/97.
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Actinomycins are a class of compounds consisting of phenoxazinone-like core attached to two peptidolactone rings, denoted as α and β. A unique component of a few families—actinomycins G, Y, and Z—is a chlorinated β-ring threonine residue. Families G and Y also contained an actinomycin that possess a β-ring heterocycle (actinomycins G5 and Y5, respectively); prior to this work, no β-ring heterocycle-containing actinomycins were reported for the Z family. Unlike other actinomycin derivatives, Y5’s cytotoxicity was abolished while still maintaining some antibacterial potency.
We constructed a model compound to probe the physical properties of the actinomycin core to test conditions under which heterocycle formation would occur. We also analyzed the gene clusters of these actinomycin producers for gene candidates to from this structural motif. We found the the actinomycin core aniline to have pKa values of 2.976 and 8.429 and a significant shift in UV absorption between 300-310nm when the group becomes charged. We also found cyclization conditions and no obvious gene candidates to form the β-ring heterocycle based on our gene cluster analysis. We hypothesize that the familial diversity of the actinomycin G, Y and Z familes is due to the reactivity of the phenoxazinone-like core.
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Thieury, Charlotte. "Recherche de composés cytotoxiques dans la biodiversité végétale de la Nouvelle-Calédonie." Thesis, Nouvelle Calédonie, 2016. http://www.theses.fr/2016NCAL0007.
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Aussi ancienne que la conscience humaine, la correspondance entre les plantes et leurs vertus thérapeutiques est connue. Une analyse de nos pharmacopées montre qu’encore aujourd’hui l’Homme va chercher ces médicaments dans la nature. Cette étude sur les substances anticancéreuses s’est attachée à valoriser la nature comme source de nouvelles substances dites « leads », composés bioactifs qui sont les chefs de file à la base du développement du médicament.La première partie de cette étude s’est attachée à la pharmacomodulation d’une molécule naturelle anticancéreuse issue d’une plante localement connue. 23 dérivés de flavokavaïnes (FKD) ont été synthétisés pour permettre d’améliorer la compréhension des exigences structurelles nécessaires pour une cytotoxicité et une sélectivité optimale via une étude de RSA. Six molécules ont montré des améliorations importantes en terme d’activité et de sélectivité. L’étude de leurs mécanismes d'action a révélé que les FKD induisaient un arrêt du cycle cellulaire variable selon le statut p53 des lignées ainsi qu’une apoptose. Les délais d’action des FKD dépendaient du statut Akt/mTOR des lignées cancéreuses. La seconde partie de cette étude s’est attachée à l’exploration phytochimique de plantes endémiques de la Nouvelle-Calédonie en vue de découvrir de nouvelles sources de molécules cytotoxiques. Un criblage des activités cytotoxiques a permis de mettre en évidence des activités intéressantes chez Diospyros olen, Meiogyne baillonii et de plusieurs espèces de Soulamea. Un travail de phytochimie a permis d’isoler de nombreuses molécules dont trois nouvelles : la sapranthine H et les macrocarpasines A et B. L’aristolactame BII et l’elliptinone présentaient des activités cytotoxiques fortes. L’aristolactame BII s’est avérée entrainé un arrêt du cycle cellulaire dépendant du statut p53 des lignées cancéreuses.Ce travail de valorisation est indispensable dans un objectif de protection d’une biodiversité menacée comme l’est celle de la Nouvelle-Calédonie pour permettre la mise en place de programmes de sauvegarde<br>As old as human consciousness, correspondence between plants and their healing properties is known. An analysis of our pharmacopoeia shows that even now humans seek these drugs in nature. This study on anticancer drugs has focused on valuing nature as a source of new substances named "leads", bioactive compounds that are at the base of drug development.The first part of this study focused on the pharmacomodulation of a natural anticancer molecule from a locally-known plant. 23 flavokawain derivatives (FKD) were synthesized to improve the understanding of the structural requirements necessary for optimal selectivity and cytotoxicity via an SAR study. Six molecules have shown significant improvements in terms of activity and selectivity. The study of their mechanisms of action revealed that FKD induced a variable cell cycle arrest depending on the p53 status of cancer cell lines as well as apoptosis. The action delays of FKD depended of Akt/mTor status of cancer cell lines. The second part of this study focused on the phytochemical exploration of new caledonian endemic plants to discover new sources of cytotoxic molecules. The ccreening of cytotoxic activities helped to highlight interesting activities in Diospyros olen, Meiogyne baillonii and several species of Soulamea. A phytochemistry work led to the isolation of many molecules including three news: sapranthine H and macrocarpasines A and B. Aristolactame BII and elliptinone exhibited strong cytotoxic activity. Aristolactame BII led to a cell cycle arrest depending on the p53 status of cancer cell lines.This valuation work is essential in an objective of protecting an endangered biodiversity like it’s the case in New Caledonia to allow the establishment of backup programs
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Svangård, Erika. "Cytotoxic Cyclotides : Structure, Activity, and Mode of Action." Doctoral thesis, Uppsala universitet, Institutionen för läkemedelskemi, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6028.
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Cyclotides are small cyclic plant proteins, and this thesis addresses their cytotoxic structure-activity properties and their mode of action on human cancer cell lines. Cyclotides were isolated from Viola odorata and Viola tricolor; three novel cyclotide sequences and two known sequences, but of new origin, were identified using mass spectrometry, amino acid analysis, and Edman degradation. The cyclotide structure includes three disulphide bonds in a knotted arrangement, which forces hydrophobic amino acid residues to be exposed on the surface of the molecule; 3-D homology models of cyclotides have revealed an amphipathic surface and charged residues located at similar positions in the molecules. The charged amino acid residues were shown to play a key role in the cytotoxicity of the cyclotide cycloviolacinO2 on a human lymphoma cell line. Methylation of Glu caused a dramatic change in cytotoxicity, lowering the potency 48 times, whereas concealing the charge of Arg with 1,2-cyclohexanedione caused virtually no change in potency. Acetylation of the two Lys caused a 3-fold reduction in potency, and masking all positive charges caused a 7-fold reduction. Additionally, disturbing the amphipathic structure by reducing and alkylating the disulphide bonds abolished the cytotoxicity. The time dependency of cytotoxicity and cell gross morphology after cyclotide exposure were investigated on the lymphoma cell line. Cells exposed to 4 µM of cycloviolacinO2 showed necrotic characteristics, such as membrane disintegration, within 5 min; a membrane disruptive effect of cycloviolacinO2 was also observed in a functional assay based on liposomes at a peptide-to-lipid molar ratio of 6.5. The anti-tumour properties of cycloviolacinO2 were evaluated on three human cancer cell lines using the hollow fibre assay in vitro and in vivo. The cyclotide exhibited potent anti-tumour activity in the micro-molar concentration range on all cell lines in vitro, but no effect on tumour growth could be established in vivo.
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Felth, Jenny. "Studies of Cytotoxic Compounds of Natural Origin and their Mechanisms of Action." Doctoral thesis, Uppsala universitet, Avdelningen för farmakognosi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-148114.
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Cancer incidence is increasing and novel anticancer drugs with new mechanisms of action are essential for future chemotherapeutic treatment. Natural products have historically played an important role in the development of anti-cancer drugs and have potential to do so also in the future. In this thesis two classes of natural products are identified as possible drug lead candidates, and the mechanisms of their action are elucidated. Initially, in a screening of a compound library for cytotoxic effects in colon cancer cells, natural products with potent activity were identified. Based on their potency, and on previously reported activities in cancer cells, two main groups of compounds, cardiac glycosides (CGs) and gambogic acid (GA) analogues, were selected for further in-depth studies. The concentration-dependent cytotoxicity was confirmed in cell lines of different origin. Cardiac glycosides were mainly evaluated for their activity in colon cancer cells and in leukemic cells, whereas the GA analogues were studied using a resistance-based panel of ten human cancer cell lines. Using activity profiles and the ChemGPS-NP model, the compounds were compared, structurally and mechanistically, to standard chemotherapeutic drugs. The results from these analyses suggested that the CGs and the GA analogues act by mechanisms different from those of antimetabolites, alkylating agents, topoisomerase I and II inhibitors, or tubulin-active agents. By analysis of drug-induced gene expression, one GA analogue, dihydro GA, was identified as a possible inhibitor of the ubiquitin-proteasome system (UPS), and the CGs showed similarities to protein synthesis inhibitors. Starting from these hypotheses, we further investigated the mechanisms of actions on a molecular level. The results showed that GA and dihydro GA act as inhibitors of the 20S proteasome chymotrypsin activity, leading to accumulation of ubiquitinated proteins. The CGs were confirmed to inhibit protein synthesis in colon cancer cell lines. However, interestingly, in leukemia cell lines, it seemed that the CGs act through a different, yet unexplored, mechanism of action. The leukemic cells (pre-B and T-ALL) were particularly susceptible to the cytotoxic effects of CGs, including at concentrations that may be achievable in the clinic.
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Le, Pogam-Alluard Pierre. "Analyses de lichens par spectrométrie de masse : déréplication et histolocalisation." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S056/document.
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Les lichens, organismes symbiotiques associant un champignon et un partenaire photosynthétique (algue verte et/ou cyanobactérie), sont caractérisés par la biosynthèse de métabolites secondaires uniques dotés de bioactivités variées. Pour valoriser au mieux cette ressource privilégiée, des méthodes innovantes de spectrométrie de masse ont été développées dans le but de minimiser la préparation de l’échantillon et la durée des analyses. Deux techniques de spectrométrie de masse ont été évaluées en ce sens : le DART-MS et le LDI-MS. L’apport de chacune de ces deux méthodes a pu être établi sur un large panel de lichens, représentant une part importante de l’espace chimique couvert par ces organismes. Il a été démontré que des profils chimiques complets pouvaient être obtenus respectivement à partir de thalles lichéniques et d’extraits acétoniques totaux. Compte tenu de la très large utilisation de la CCM pour l’analyse chimique de lichens, les possibilités offertes par le couplage de la CCM à l’ionisation electrospray ont également été explorées. Une seconde partie de ces travaux avait pour but de cartographier la distribution des métabolites secondaires au sein du thalle lichénique. À ces fins, des analyses d’imagerie LDI ont été réalisées sur une coupe transversale d’un lichen crustacé modèle : Ophioparma ventosa. Ce lichen a été étudié en phytochimie pour identifier six napthopyranones à partir des apothécies dont quatre nouvelles structures. Les principaux métabolites de ce lichen ont pu être imagés par LDI-MSI avec une résolution spatiale de 50 μm environ. Une corrélation entre la distribution des molécules et leur rôle écologique présumé permet d’avancer des hypothèses d’écologie chimique. Des approches conjointes reliant histolocalisation et étude génétique des partenaires de la symbiose ont été entreprises. La recherche des gènes de la biosynthèse de la mycosporine sérinol chez les symbiontes isolés de Lichina pygmaea par microdissection capture laser a été initiée en ce sens. D’autres approches innovantes comme l’analyse cristallographique par diffraction de poudre par les rayons X sont également abordées dans ce document articulé autour de six publications issues de ce travail et de deux articles en cours de soumission<br>Lichens are self-sustaining symbiotic partnerships comprising a fungus associated with a green alga and/or a cyanobacteria. This consortium produces unique secondary metabolites that are endowed with various biological activities. To harness this privileged chemodiversity, innovative mass spectrometry techniques were developed in the course of this study to accelerate the dereplicative holdup through both a minimal sample preparation and a decrease of the time of analysis. Two approaches were considered during this work: DART-MS and LDI-MS and their adequacy for lichen dereplication was assessed on a vast array of samples encompassing a wide range of metabolites. Both of them facilitated complete chemical profiles, respectively from unprocessed lichen material and crude acetone extracts. Since TLC still enjoys a wide-spread popularity among lichenologists, the advantages offered by TLC-ESI-MS hyphenation were evaluated as well. A second part of this manuscript focused on the histolocalization of lichen metabolites. For this purpose, LDI mass spectrometry imaging studies were undertaken on the crustose lichen Ophioparma ventosa. The phytochemical investigation of this species afforded the isolation of six naphthopyranones from its apothecia, four of them being new molecules. LDI-MSI revealed the distribution patterns of all the main metabolites of this lichen, reaching a spatial resolution of 50 μm. Most interestingly, the distribution pattern of imaged metabolites within the thallus is highly organized and is related to their ecological relevance. Joint strategies combining histolocalization and genetic investigation of lichen symbionts separated using laser capture microdissection were also considered. As such, an investigation of the biosynthesis of mycosporine serinol within Lichina pygmaea dissociated symbionts was initiated. Further analytical strategies such as X-ray powder diffraction are introduced in this thesis that contains six publications and two drafts to be submitted
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Wei, Lai, and 魏来. "Induction of LTB4 12-hydroxydehydrogenase (LTB4DH) by Radix Astragali and Radix Paeoniae Rubra: a study of theactive compounds and related biological functions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B44683443.
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Beraldo, Josseara. "Estudo farmacognóstico de Passiflora edulis Sims. (Passifloraceae)." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-14092017-125247/.
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Os extratos de espécies de Passiflora (Passifloraceae), comumente empregados no tratamento de diversas doenças em regiões tropicais e subtropicais, têm se mostrado fonte em potencial de medicamentos. O uso popular de espécies vegetais pertencentes a esse gênero decorrente de suas propriedades sedativas consta a partir do século 17 na Europa. Após cerca de 200 anos, foram documentados os estudos farmacológicos iniciais com P. incarnata. No Brasil, uma espécie morfologicamente assemelhada a essa - P. edulis Sims. - tem encontrado uso como sedativo, ansiolítico, diurético e no tratamento de distúrbios gastrintestinais, embora esta espécie seja explorada comercialmente na produção de sucos concentrados. Pesquisadores têm avaliado a atividade de extratos de folhas de P. edulis no sistema nervoso central. Considerando o uso popular e a falta de trabalhos científicos avaliando a ação no sistema digestório, o extrato liofilizado preparado com as folhas e com os caules dessa espécie foi ensaiado em ratos, empregando-se solução de etanol acidificado como indutor de úlceras. A triagem fitoquímica e a avaliação da atividade antioxidante (DPPH, ORAC) foram realizadas para verificar o potencial uso dos metabólitos encontrados no extrato. O método espectrofotométrico foi empregado na análise do teor flavonoídico. As técnicas de Cromatografia Líquida de Alta eficiência (CLAE) e espectrofotometria UV/visível foram utilizadas para analisar as frações f1avonoídicas. A caracterização morfoanatômica das folhas e dos caules da espécie foi efetuada como auxiliar no controle de qualidade da droga vegetal. No modelo ensaiado, o extrato de P. edulis não mostrou atividade antiúlcera promissora. Nessa fase não se pode descartar seu uso no tratamento de úlceras gástricas. O extrato liofilizado apresentou teor flavonoídico de 1,2% e atividade antioxidante, demonstrada com os métodos empregando DPPH (EC50 de 160 µg/mL) e ORAC (775,35 ± 36,12 µmol eq Trolox/g de extrato). Na análise preliminar das frações flavonoídica foi evidenciada a predominância de flavonas. Caracteres morfoanatômicos importantes na análise da droga vegetal foram documentados.<br>The extracts of Passiflora spp. (Passifloraceae), commonly used in the treatment of several diseases from tropical and subtropical regions, have been proving to be a potential source for the preparation of medicines. Because of theirs sedating properties, popular use of vegetal species belonging to this genus has been found since the 17th century in Europe. Then, after 200 years, early pharmacologic studies with P. incarnata were documented. In Brazil, one species morphologically similar to this one - P. edulis Sims. - has been used as sedative, anxiolytic, diuretic and for the treatment of gastrointestinal diseases, although this species has been commercially explored in the production of concentrated juices. Researchers have been evaluating the effects of the extract of P. edulis leaves in the central nervous system. Considering its popular use and the lack of scientific research evaluating its effect in the digestive tract, the freeze-dried extract prepared with its leaves and stems was tested in rats. Acute gastric lesions were induced by acidified solution of ethanol. The phytochemical screening and the antioxidant effects evaluation (DPPH, ORAC) have been carried out in order to evaluate the potential use of metabolites found in the extract. The spectrophotometric method was applied in the analyses of flavonoids content. High Performance Liquid Chromatography (HPLC) and UV/ visible methods were used to analyze the flavonoid fractions. Morphoanatomic characterization of leaves and stems of the species was done to applied in the quality control of the crude drug. In the tested model, P. edulis extract did not show its potential gastroprotective property. At this point we can not discard its use to treat gastric ulcers. The flavonoid content quantified in the extract were 1,2%. The freeze¬dried extract presented antioxidant activity, demonstrated with DPPH (EC50 de 160µg/mL) and ORAC (775,35 ± 36,12 µmol eq Trolox/g) methods. The chemical profile of flavonoid fractions showed predominant concentration of flavones. Important morphoanatomic characters of the crude drug were documented.
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Ruggiero, Andrea de Andrade. "Estudo farmacognóstico do jambolão Syzygium cumini (L.) Skeels Myrtaceae." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-27022015-095201/.
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Syzygium cumini (L.) Skeels (Myrtaceae) encontra uso na medicina tradicional como hipoglicemiante. Folhas mostram emprego adicional , no tratamento de úlceras pépticas, diarréias e hemorróidas. A dissertação apresenta descrições macro e microscópicas das folhas, acompanhadas de fotografias. Teores de flavonóides, saponinas e taninos foram determinados no extrato hidroetanólico liofilizado e na droga coletada no verão e outono. O óleo volátil foi analisado. O extrato foi avaliado quanto à atividade antimicrobiana, antioxidante e toxicidade aguda. Os flavonóides (0,53%-0,62%), saponinas (4,22%-8,64%) e taninos (3,47-4,15%) apresentaram teores elevados no outono. No extrato, teores de flavonóides: saponinas e taninos foram de 2,19%, 10,92% e 13.97%, respectivamente.α-pineno, α-terpineol, β-pineno e limoneno foram os componentes majoritários do óleo. O extrato não revelou sinais de toxicidade aguda, e não apresentou atividade contra bactérias e fungos até 1.000µ-g/mL. O extrato apresentou atividade antioxidante. Os dados obtidos contribuem para melhor conhecimento da espécie e no controle de qualidade.<br>Syzygium cumini (L.) Skeels (Myrtaceae) is a hipoglycemic in folk medicine. Its leaves are also used as anti-ulcer, anti-diarrheic and antihemorrhoid. This work brings macro and microscopic descriptions of the leaves, with photos. Flavonoids, saponins and tannins contents were determinated in the liophylizated hydroethanolic extract and in the drug collected in summer and falI. The volatile oil was analysed. The antimicrobial and antioxidant activities and the acute toxicity were avaliated . The flavonoids (0.53%-0.62%), saponins (4 .22%-8.64%) and tannins (3.47%-4-15%) showed their highest values in the fall sample. The contents of flavonoids, saponins and tannins in the extract were, 2.19%, 10.92% and 13.97%, respectively. α-pinene, α-terpineol, β and limonene were the major constituents of the oil. The extract showed no signs of acute toxicity nor was it active against bacteria and funghi up to 1,000µg/mL . The extract showed antioxidant activity. These data contribute for a better knowledge of the specie and quality control.
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Fletcher, Joshua Nehemiah. "Isolation, Identification, and Biological Evaluation of Potential Flavor Modulatory Flavonoids from Eriodictyon californicum." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1322496872.
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Béjar, Ezra. "Kinetic studies of the spasmogenic effects of serotonin and isolates from Byrsonima crassifolia leaves on rat fundus." Scholarly Commons, 1991. https://scholarlycommons.pacific.edu/uop_etds/507.
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Leaf and bark extracts of a Mexican medicinal plant, Byrsonima crassifolia (Malpighiaceae), exhibited spasmogenic effects on isolated rat fundus and biphasic effects on jejunum and ileum. Preliminary evaluations using rat fundus in Krebs solution indicated that the activity of a 2% acetic acid extract of eaves (HOAcE) could be split into two types: (i) high-efficacy, low-potency, n-butanol-extracted, pargyline- and 1-(1-naphtylpiperazine) (1-NP)-sensitive, atropine-insensitive activity, and (ii) low-efficacy, high-potency, ethyl acetate-extracted, pargyline-insensitive, atropine- and 1-NP-sensitive activity. HOAcE lacked muscarinic and nicotinic effects on rat jejunum and frog rectus abdominis. Serotonin (5-HT) and HOAcE curves in fundus were parallel and 5-HT potency was 6,037 times that of HOAcE (95% confidence limits: 4,624-7,852). The pD2 (affinity constant) for 5-HT was 7.96 (7.92-8.00) with pargyline added to the medium. 5-HT receptor-interaction kinetics using cholinergics and 5-HT agonists and antagonists was carried out. 1-NP competitively antagonized 5-HT. The 5-HT, antagonist s-(-)propranolol did not significantly antagonize 5-HT. The 5-HT2 blocker ketanserin noncompetitively antagonized 5-HT and α-Me-5-HT (pD'2 = 5.6 and 6.7, respectively). The 5-HT3 antagonist MDL-72222 inactivated only a small proportion of receptors (pD'2 = 6.46). Atropine did not significantly modify the curve of 5-HT while fluoxetine noncompetitively antagonized 5-HT (pD'2 = 5.8). 5-HT and α-Me-5-HT curves were biphasic indicating two receptor interactions (high and low affinity). High-affinity pD2 values for six different 5-HT agonists and 1-NP on rat fundus correlate well with reported rat brain (radioligand binding) pKd values at the 5-HT1C receptor (r = 0.94). Large scale extraction and fractionation of a methanol extract of leaves yielded two peaks of activity (Peak 1, lipophilic; Peak 2, polar). Peak 1 contained Compounds 1 to 7 (C1-C7); Peak 2 included C8-C15. Compound 1, C2, C3, C4, C10 and C11 were inactive while C8, C12 and C13 showed equivocal effects. Compound 5, C6, C7, C9, C14, C15, quercetin and gallic acid were active. Potencies were: C5 > C6 > C7 = quercetin > C9 > gallic acid. Efficacy (IA) was: C15 ≥ C14 > gallic acid > C9 > C5 > C7 > quercetin > C6. Compound 9 and its aglycone quercetin were partial agonists (C9 IA = 70%, pD2 = 6.35; quercetin IA = 60%, pD2 = 6.58). Compound 9 noncompetitively antagonized 5-HT (pD'2 = 6.10), while quercetin did not. Compound 14 and C15, the most active compounds, had similar response curves but these curves were not parallel to 5-HT. Spasmogenic ED50 values for C14 = 0.76 (0.38-1.54) μg/mL and C15 = 0.76 (0.41-1.42) μg/mL. Gram for gram 5-HT was 181 x C14 and 182 x C15.
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Lane, Amy L. "Marine natural products as antimicrobial chemical defenses and sources of potential drugs." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26556.
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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009.<br>Committee Chair: Kubanek, Julia; Committee Member: Fernandez, Facundo M.; Committee Member: Harvey, Stephen C.; Committee Member: Hay, Mark E.; Committee Member: Hud, Nicholas V. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Bajaber, Majed Abdullah. "Study of Iridium Catalyzed N-Alkylation of Urea with Benzyl Alcohols." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1863.
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The solvent-free (Cp*IrCl2)2 catalyzed N-alkylation of urea with benzyl alcohol has been studied. A variety of reaction conditions were studied and optimized to produce a high yield (82%) of N,N-dibenzylurea. A series of substituted benzyl alcohols were examined at the optimal reaction conditions. However, the preparation of substituted benzyl urea derivatives using conditions optimized for benzyl alcohol gave poor yields or intractable mixtures.
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Sjögren, Martin. "Bioactive Compounds from the Marine Sponge Geodia barretti : Characterization, Antifouling Activity and Molecular Targets." Doctoral thesis, Uppsala universitet, Institutionen för läkemedelskemi, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6797.
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The marine sponge Geodia barretti produces a range of secondary metabolites. Two of these compounds were isolated and elucidated guided by their ability to inhibit settlement of cypris larvae of the barnacle Balanus improvisus. The compounds barettin (cyclo-[(6-bromo-8-en-tryptophan)-arginine]) as E/Z mixture and 8,9-dihydrobarettin (cyclo-[6-bromo-tryptophan)-arginine]) were determined by using mass spectrometry, nuclear magnetic resonance and quantitative amino acid analysis.The bioactivity of these brominated dipeptides is in the range of antifouling substances used today: EC50 values of 0.9 µM (barettin) and 7.9 µM (8,9-dihydrobarettin). The compounds were successfully synthesised and then tested in a field experiment to evaluate their antifouling properties. The compounds were incorporated in four different commerical, non-toxic marine coatings. The concentrations of the compounds were 0.1 and 0.01% (w/w) and coated panels were exposed to field conditions for eight weeks. The experiment evaluated the effect of barettin and 8,9-dihydrobarettin on recruitment of the barnacle B. improvisus and the blue mussel Mytilus edulis (major Swedish foulers). The most efficient paint was a SPC polymer, for which the reduction of recruitment of B. improvisus was 89% with barettin (0.1%) and 61% with 8,9-dihydrobarettin (0.1%). For M. edulis the reduction of recruitment was 81% with barettin (0.1%) and 72% with 8,9-dihydrobarettin (0.1%) with the same SPC paint. Furthermore, 14 analogs of barettin and dipodazine were synthesised and tested for their ability to inhibit larval settlement. Two of the analogs have a barettin scaffold and twelve have a dipodazine scaffold. Six of the analogs displayed significant settlement inhibition with the most potent inhibitor being benzo[g]dipodazine (EC50 value 0.034 µM). The effect of benzo[g]dipodazine was also shown to be reversible. Finally, an investigation of the mode of action was performed on 5-HT receptors. Barettin demonstrated a specific affinity to 5-HT2A, 5-HT2C and 5-HT4, while 8,9-dihydrobarettin interacted only with 5-HT2C of the receptor subtypes tested (5-HT1-5-HT7).
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Burman, Robert. "Distribution and Chemical Diversity of Cyclotides from Violaceae : Impact of Structure on Cytotoxic Activity and Membrane Interactions." Doctoral thesis, Uppsala universitet, Avdelningen för farmakognosi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-131104.
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During the last decade there has been increased interest in the cyclotide protein family, which consist of a circular chain of approximately 30 amino acids, including six cysteines that form three disulfide bonds, arranged in a cyclic cystine knot motif. This thesis gives new insights in cyclotide distribution and occurrence in the plant family Violaceae, structure-activity relationships for cytotoxic effects, membrane disruption and adsorption on lipid membranes, and evaluates toxicity and anti-tumor activity in vivo. A large-scale analysis was done on over 200 samples covering 17 of the 23 genera in Violaceae, and cyclotides were positively identified in almost 150 of approximately 900 known species. Conclusions are that the Violaceae is an extremely rich source of cyclotides, and that they are ubiquitous among all species in that plant family. After investigating the cyclotides' cytotoxicity it was evident that the effects were immediate and occurred at low micromolar concentrations. To understand the relationships between structure and activity, approximately 30 cyclotides and cyclotide derivates were assayed for cytotoxicity. Results showed that the overall charge is of minor influence on activity and revealed a strong correlation between an intact hydrophobic molecular surface and cytotoxic effect. The cytotoxic activity is mainly due to interactions between peptides and target membranes, illustrated by prototypic cyclotides' ability to induce liposome leakage and adsorb to lipid membranes. Cyclotides were strongly lytic against zwitterionic liposomes, less when cholesterol was included, while for anionic liposomes, activity depend on the net charge of cyclotide. A similar pattern was observed for the adsorption of the cyclotides to anionic bilayers, in which strong lytic activity was coupled with high adsorption. To further evaluate cyclotides cytotoxic effects, in vivo studies were conducted, both for acute toxicity and anti-tumor efficacy in mice. Two different methods were used: hollow fiber method and traditional xenografts, but no significant anti-tumor effects were detected. The results indicate that anti-tumor effects are minor or absent at tolerable doses and that cyclotides have a very abrupt in vivo toxicity profile, with lethality after single injection at 2.0 mg/kg.