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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Morfologia de Amaryllidaceae S.S. nativas do Nordeste brasileiro

Geyson Alves Araújo, Anderson January 2007 (has links)
Made available in DSpace on 2014-06-12T15:06:44Z (GMT). No. of bitstreams: 2 arquivo4857_1.pdf: 1653912 bytes, checksum: fa27a80f0afd0f74ec13a74b17072bdc (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Constituída por cerca de 60 gêneros e 850 espécies, Amaryllidaceae s.s. possui ampla distribuição geográfica. No Brasil ocorrem aproximadamente 15 gêneros e um número estimado de 150 espécies, das quais cerca de 30 nomes foram propostos como nativas da região nordeste. Visando colaborar para o conhecimento das espécies nativas da região, foi elaborado o levantamento de representantes de Amaryllidaceae s.s. e Alliaceae s.s. nordestinas, bem como também foram realizados estudos morfológicos, anatômicos e palinológicos como subsídios à sua taxonomia. Foram identificadas 23 espécies, sendo 21 representantes de Amaryllidaceae s.s. pertencentes aos gêneros Griffinia, Habranthus, Hippeastrum, Hymenocallis e Zephyranthes e duas espécies de Nothoscordum (Alliaceae s.s.). A forma das folhas e escapos, número de flores por inflorescências, posição do ovário, simetria floral e comprimento do hipanto são algumas das mais importantes características morfológicas utilizadas para o reconhecimento interespecífico. Estruturalmente, os caracteres foliares e dos escapos podem atuar como diagnósticos para a segregação de agrupamentos em nível de família, gêneros ou espécies. Laticíferos foram detectados apenas em Nothoscordum pernambucanum, enquanto que a ausência de colênquima nos escapos e presença de cavidades de ar exclusivamente esquizógenas segregam Habranthus e Zephyranthes candida, respectivamente, das demais espécies. Escapo biconvexo é um caráter exclusivo de Griffinia e Hymenocalllis. A forma da folhas, em ST, é diversa em Habranthus. Assim como, Hippeastrum puniceum distingue-se de Hip. stylosum por apresentar floema nacarado. A segregação do grupo aqui analisado através do conjunto de caracteres anatômicos pode ser mais seguramente empregada em nível genérico. Todas as espécies apresentaram grãos de pólen em mônades, heteropolar-bilaterais, monossulcados e âmbito elíptico/elipsoidal. Foram detectadas características diagnósticas com relação ao padrão de ornamentação, destacando Hippeastrum stylosum e Hymenocallis littoralis por possuirem grãos de pólen com calotas equatoriais. Os dados macro e micromorfológicos observados dentre os táxons analisados responderam, com ressalvas, à taxonomia do grupo
22

Studies on the anthocyanin pigments in Allium amplectens Torr

Chu, Chun-Mei 01 January 1972 (has links)
In this investigation, the basic pigment component, or anthocyanidin, of the ten most common spots was identified using paper and thin layer chromatographic techniques.
23

Deriváty Amaryllidaceae alkaloidu vittatinu jako potenciální léčiva / Derivatives of Amaryllidaceae alkaloid vittatine as potential drugs

Teplanská, Michaela January 2021 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Michaela Teplanská Supervisor: PharmDr. Daniela Hulcová, Ph.D. Title of diploma thesis: Derivatives of Amaryllidaceae alkaloid vittatine as potential drugs Haemanthamine type Amaryllidaceae alkaloids are characterized by interesting biological activity. This group also includes alkaloid vittatine with antitumor, antibacterial, antifungal and antimalarial effects. Although vittatine does not inhibit cholinesterases, its derivatives have shown promising activity against butyrylcholinesterase, which is one of the targets of potential drugs in the treatment of Alzheimer's disease. Another series of semisynthetic vittatine derivatives was prepared in order to examine their biological activity. Reactions with acyl chlorides gave 11 aromatic esters. Identification of the prepared substances was performed by ESI HRMS, NMR and optical rotation measurements. The derivatives were tested for inhibitory activity against human cholinesterases. The results show that the substances were not active against acetylcholinesterase, but almost all of them inhibited butyrylcholinesterase. The most active was 3-O-(6-chloro-2- fluoro-3-methylbenzoyl)vittatine with an IC50 value 0.29 ± 0.03 μM. According to the calculated value...
24

A taxonomic re-evaluation of the Allium sanbornii complex

Denison, Stella Sue 01 January 1986 (has links) (PDF)
Allium sanbornii is a member of the Sanbornii alliance which is characterized by prominent ovarian crests and a single terete leaf. Because of inadequate material, previous investigators have confused species limits and lumped together taxa that are not conspecific. This investigation included herbarium and field studies and determined that previously ignored characters, such as the relative lengths of the inner and outer perianth segments, general attitude of the perianth segments and texture of the outer bulb coat, were useful in delimiting relationships within the complex. Based on these findings Allium sahbornii consists of two geographic variants: A. sahbornii var. sanbornii and A. sanbornii var. congdonii. The two other currently recognized varieties are elevated to specific status as A. jepsonii and A. tuolumnense.
25

Alkaloidy rostlin čeledi Amaryllidaceae a jejich biologická aktivita 1. / Alkaloids of the family Amaryllidaceae and their biological activity 1.

Mišáková, Kamila January 2014 (has links)
Mišáková K: Alkaloids of the Amaryllidaceae family and their biological activity 1. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2014, 63 p. The aim of the diploma thesis was a preparation of alkaloidal extract from Nerine Bowdenii to izolation of 2 pure alkaloids by column and thin layer chromatography. Subsequently these two alkaloids were subjected to structural MS and NMR analysis and tested for biological activity against human cholinesterases (HuAChE and HuBuChE) and for antioxidant and cytotoxic activity. Isolated substances were identified as ambelline and undulatine alkaloids, which have been already described previously in this plant. In the test for determining cholinesterase inhibitory activity of ambelline and undulatine the following values were measured; for ambelline: IC50, HuAChE = 169 ± 7 μM a IC50, HuBuChE = 985 ± 25 μM, for undulatine: IC50, HuAChE = 23,52 ± 1,19 μM a IC50, HuBuChE > 1000 μM. Galanthamin (IC50, HuAChE = 1,71 ± 0,007 μM, IC50, HuBuChE = 42,30± 1,30 μM), huperzin A (IC50, HuAChE = 0,033 ± 0,001 μM, IC50, HuBuChE > 1000 μM) and eserin (IC50, HuAChE = 0,063 ± 0,001 μM, IC50, HuBuChE = 0,130 ± 0,004 μM) were used like a positive controls. In the test for...
26

Micropropagation and pharmacological evaluation of Boophone disticha.

Cheesman, Lee. 06 November 2013 (has links)
Boophone disticha (L.f.) Herb is one of the most widely distributed bulbous species in southern Africa. Of Africa’s many bulbous plants, it is widely known for its poisonous and medicinal properties. It is of considerable ethnobotanical interest in traditional medicine because of its hallucinogenic alkaloids and it has great potential as an ornamental due to its fan-shaped foliage and large umbel of bright pink to deep red flowers. In South Africa, many bulbous plants are used in traditional medicine which are collected from wild populations. The high demand for trade and use of such plants, that are destructively harvested, places an enormous pressure on natural populations. According to the Red List of South African Plants, the conservation status of B. disticha has been listed as ‘declining’. It is, therefore, important to develop conservation strategies for these medicinal plants, such as the development of alternative propagation methods. Micropropagation is a useful technique for rapid clonal multiplication of plant material which could alleviate the pressure on the wild plant populations, as well as potentially producing useful secondary metabolites. The in vitro induction of storage organs is especially beneficial as it can limit the loss of plants during acclimatization since bulblets are generally hardier than shoots or plantlets. Thus, the main aim of this research was to establish a micropropagation protocol which could be a valuable tool for conservation of this plant species. In addition, B. disticha plants were assessed in various ethnopharmacological assays to evaluate their medicinal properties, and a preliminary study on the population genetics was also conducted. As part of the development of a suitable micropropagation protocol, the effect of environmental and physiological factors on the initiation and growth of bulblets were investigated. These factors included the effect of various plant growth regulators, carbohydrates, temperature, photoperiod and liquid culture. Different explants (i.e. ovaries, anthers, filaments, pedicels, embryos, seeds and bulb twin-scales) were tested to determine which explants were the most suitable for subsequent experiments. Although success was limited, twin-scales proved to be the most suitable explant and it was demonstrated that activated charcoal, ascorbic acid and N6- benzyladenine were required as media supplements. Antimicrobial activity was tested between different plant parts and seasons. The plant parts (roots, leaves, outer and inner bulb scales) were extracted with a range of differing polarity solvents. These were screened for antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae, and for antifungal activity against Candida albicans. Extracts from roots of plants collected in spring and summer showed the best antimicrobial activity against B. subtilis, E. coli and K. pneumoniae, indicating that plant part and collection time do affect activity. In vitro grown bulblets also showed antimicrobial activity, demonstrating that antibacterial properties were maintained in cultured plantlets. Extracts from plants collected in summer were tested for mutagenicity using the Ames test (Salmonella/microsome assay; plate incorporation method, with or without metabolic activation). None of the extracts tested were found to induce mutations and also did not modify the effect of the mutagenic compounds (2AA with S9 and 4NQO without S9). Although the results do not indicate a mutagenic response, this does not necessarily confirm that it is not mutagenic nor carcinogenic to other bacterial strains, however, B. disticha must be used with caution, especially considering the levels of alkaloids in the plant. The two major constituent alkaloids of B. disticha were identified as buphanidrine and distichamine. In the antibacterial assay, both compounds exhibited broad-spectrum micromolarlevel activity against the two Gram-positive and two Gram-negative bacteria tested. The best MIC value, of 0.063 mg/ml, was found for bupanidrine/distichamine against S. aureus, E. coli and K. pneumonia. The isolated compounds were tested and found to be neither mutagenic nor toxic at the concentrations tested. Thus, buphanidrine and distichamine are thought to be the constituents likely responsible for the medicinal properties of the plant. To determine the level of genetic variation between different populations of B. disticha, plants were collected from six wild populations in KwaZulu-Natal, South Africa. DNA was isolated and tested for genetic variation using ten Inter Simple Sequence Repeat (ISSR) primers. The level of inter-population polymorphism ranged between 23% and 39%, showing that the populations had low genetic polymorphism. From the genetic distance results, it was found that the Midmar and Umgeni Valley populations are closely related, and these populations are similar to two sister populations. The Amatikulu and Lions River populations were similar but slightly different to the other populations. Antimicrobial assays showed minor difference in activity from the six wild populations. Although the micropropagation of B. disticha had limited success, this study did develop a successful decontamination protocol as well as determine the most useful explant and supplements. This information provides an important starting point for the development of a successful micropropagation protocol for the conservation of B. disticha. Since, B. disticha is an important medicinal plant in South Africa, this study has also deepened our understanding of the constituents that could be responsible for the medicinal properties of B. disticha and, in so doing, confirmed the value of this plant for use in traditional medicine in South Africa. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.
27

Untersuchungen zur Pharmakokinetik und emetischen Wirkung des Amaryllidaceen-Alkaloids Lycorin beim Hund: Beeinflussung durch etablierte Antiemetika

Kretzing, Sascha 04 December 2013 (has links) (PDF)
Lycorin gilt bei vielen Amaryllidaceae als Hauptalkaloid und die Aufnahme dieser Pflanzen ist eine häufige Vergiftungsursache bei Mensch und Tier. Als Hauptsymptome infolge dieser Pflanzenvergiftungen werden Nausea und Emesis genannt, aber systematische Untersuchungen zu diesen biologischen Effekten, zum Wirkmechanismus und zur Pharmakokinetik von Lycorin, das als auslösendes Agens angenommen wird, existieren bislang nicht. In der vorliegenden Arbeit werden die Zusammenhänge zwischen verabreichter Lycorin-dosis und Lycorin-induzierter Nausea und Emesis, die Beeinflussbarkeit dieser emetischen Effekte durch etablierte Antiemetika und die Pharmakokinetik von Lycorin in einem cross-over und vehikel-kontrollierten Design in vivo untersucht. Die Studie wurde an elf Beagle-Hunden beider Geschlechter durchgeführt. Die Lycorin-induzierten emetischen Effekte wurden quantifiziert und über Videoaufzeichnungen zeitnah dokumentiert. Nausea wird hierbei mittels eines Scoring-Systems quantifiziert, während die Parameter Latenzzeit, Dauer und Anzahl der Brechakte zur Beurteilung der Emesis herangezogen werden. Die subkutane Applikation von Lycorin induziert, beginnend ab einer Dosis von 0,5 mg/kg KGW Nausea und Vomitus. Eine statistische Signifikanz ist allerdings erst ab 1,0 mg/kg und ein maximaler emetischer Effekt bei einer Dosis von 2 mg/kg (ED100) zu verzeichnen. Die Ergebnisse zeigen eine Korrelation zwischen applizierter Lycorin-Dosis und Nausea-Score sowie der Anzahl der Brechakte. Lycorin-induzierte Nausea und Emesis sind in den vorliegenden Untersuchungen selbstlimitierend und dauern maximal 2,5 Stunden an. Lycorin weist in den untersuchten Dosierungen von 0,25 mg/kg bis 2,0 mg/kg eine lineare Plasmakinetik auf. Nach subkutaner Gabe werden maximale Plasmakonzentrationen (Cmax) nach 0,5 h gemessen, die mittlere Plasma-Halbwertszeit beträgt 0,67 h nach subkutaner, respektive 0,51 h nach intravenöser Applikation. Die errechnete orale Bioverfügbarkeit beträgt ca. 40 %. Das Auftreten von Nausea und Emesis, sowie deren Verlauf decken sich weitestgehend mit dem Verlauf der Lycorinkonzentration im Plasma. In keiner der untersuchten Dosisstufen sind blutchemische oder hämatologische Abweichungen aufgetreten. Um Rückschlüsse auf die Zielstrukturen von Lycorin und somit auf den emetischen Wirkungsmechanismus der Lycorin-induzierten Emesis und Nausea zu gewinnen, wurden die Hunde jeweils mit Diphenhydramin, Maropitant, Metoclopramid, Ondansetron oder Scopolamin vorbehandelt. Diese therapeutisch etablierten Antiemetika besitzen eine selektive Rezeptoraffinität und entfalten ihre antiemetische Wirkung über einen Antagonismus an histaminergen H1- (Diphenhydramin), dopaminergen D2- (Metoclopramid), muskarinergen M1-3- (Scopolamin), serotoninergen 5-HT3- (Ondansetron) oder Neurokinin-1-Rezeptoren (NK1) (Maropitant). Durch die Bindung des jeweiligen Antiemetikums an die spezifischen Rezeptoren, soll die anschließende Bindung von Lycorin an den gleichen Rezeptoren verhindert oder reduziert werden, was sich in einer Reduktion oder Abwesenheit von Nausea und Emesis auswirkt. Die Vorbehandlung mit Ondansetron ist mit einer signifikanten Verminderung der Anzahl der Brechakte verbunden und durch die Vorbehandlung mit Maropitant kann Lycorin-induzierte Emesis komplett verhindert werden. Einzig Ondansetron reduziert darüber hinaus den Ausprägungsgrad der Nausea und verlängert die Latenzzeit bis zum Auftreten von Vomitus, was eine Beteiligung von 5-HT3 Rezeptoren bei lycorin-induzierter Nausea nahe legt. Histaminerge (H1), dopaminerge (D2) und muskarinerge (M1-3) Rezeptoren sind vermutlich nicht an Lycorin-induzierter Nausea und Emesis beteiligt. Die Befunde der vorliegenden Arbeit weisen darauf hin, dass Lycorin bei Vergiftungen mit Pflanzen oder Pflanzenteilen, die zu den Amaryllidaceae gehören, eine entscheidende Bedeutung für die klinische Symptomatik und den Verlauf von Intoxikationen hat. Nach den Ergebnissen dieser Arbeit sind eine prädominierende Beteiligung von NK1- und eine etwas geringer ausgeprägte Beteiligung von 5-HT3-Rezeptoren im emetischen Wirkmechanismus wahrscheinlich. Somit erscheint die therapeutische Anwendung von Maropitant beim Hund (und evtl. Apreptitant beim Menschen) und/oder Ondansetron zur symptomatischen Behandlung anhaltender Nausea und Emesis bei Pflanzenvergiftungen mit Amaryllidacaen bei denen die Wirkung von Lycorin dominiert, wissenschaftlich begründet und klinisch von Vorteil gegenüber anderen antiemetischen Prinzipien zu sein.
28

Atividade anti-trichomonas vaginalis de alcaloides de amaryllidaceae e análogos de poliaminas : análise química, semi-síntese e investigação do mecanismo de ação

Giordani, Raquel Brandt January 2010 (has links)
A família Amaryllidaceae é reconhecida como fonte de compostos bioativos, sendo o isolamento e elucidação estrutural de seus alcaloides, aliado às avaliações farmacológicas, um tema importante. Estudos mostram que o mecanismo de ação da citotoxicidade desses alcaloides é seletivo e depende da linhagem celular. Trichomonas vaginalis é um protozoário parasita que causa a tricomonose, a doença sexualmente transmissível de origem não viral mais comum no mundo. Além de ser considerado um importante organismo patogênico, suas características bioquímicas peculiares, como a ausência de mitocôndrias, torna o tricomonas um adequado modelo para estudos de vias metabólicas de morte celular. A atividade anti-T. vaginalis dos alcaloides de Amaryllidaceae licorina e candimina, assim como o potencial citotóxico de diaminas sintéticas, foram investigados. Estudos de semi-síntese com a licorina também foram desenvolvidos. Nossos resultados mostraram que a licorina e candimina induzem importantes alterações na ultraestrutura dos parasitos e nenhum marcador morfológico clássico de apoptose, como corpos apoptóticos, foi observado. Além disso, nem a fragmentação do DNA genômico nem a exposição de resíduos de fosfatidilserina foram detectadas. Por outro lado, ambos os alcaloides atrasaram o ciclo celular do parasito e inibiram a atividade das enzimas NTPDase e ecto-5`- nucleotidase, importantes na manutenção da relação parasito/hospedeiro. O alcaloide pró-apoptótico licorina e a candimina induziram morte celular no parasito amitocondriado T. vaginalis por um mecanismo de ação que não cumpre as características morfológicas de apoptose. Entretanto, similaridades com a morte celular denominada paraptose foram observadas: intensa vacuolização citoplasmática periférica aliada à integridade nuclear. Considerando que a citotoxicidade dos alcaloides pode ser considerada moderada (250 μM), derivados de poliaminas foram escolhidos para desenvolver estudos de semi-síntese com a licorina e aperfeiçoar a atividade do alcalóide. Poliaminas são moléculas catiônicas de estruturas simples, essenciais para a diferenciação celular e regulação do ciclo celular. Neste trabalho demonstrou-se a síntese e avaliação da atividade anti-T. vaginalis de uma série de derivados de diaminas, dos quais N-hexadecil-1,4-butanodiamina apresentou CIM igual a 2,5 μg/ml, duas vezes mais ativo em comparação ao metronidazol, utilizado como composto de referência. A hibridização molecular da licorina com as diaminas foi prejudicada pela instabilidade da licorina mesilada, intermediário chave para prosseguir a rota sintética. No entanto, seis derivados inéditos da licorina, todos ésteres, aromáticos ou alifáticos, foram sintetizados. / Amaryllidaceae family has proven to be plentiful sources for therapeutic agents. Hence, the isolation, biology and chemistry of the Amaryllidaceae alkaloids make an important subject. Investigations on cytotoxic mechanisms of these alkaloids indicate a promising selective cell-type-dependent cytotoxicity. Trichomonas vaginalis is a parasite that causes trichomonosis, the number one non-viral sexually-transmitted disease in the world. However, whilst T. vaginalis is a prime pathogenic target, its lack of mitochondria makes it a suitable biochemical model to study cell death-related mechanisms. Anti-T. vaginalis activity of lycorine and candimine alkaloids were investigated, as well as the cytotoxic potential of diamine analogs. Finally, studies on lycorine semi-synthesis were developed. Our results showed that, after lycorine and candimine treatment, no hallmark suggestive of apoptosis were observed, such as apoptotic bodies, but instead several important ultrastructural alterations, assessed by electronic microscopy. Additionally, DNA fragmentation and membrane phosphatidylserine exposure were not detected. Analysis showed that lycorine and candimine arrested T. vaginalis cell cycle and inhibited the NTPDase and ecto-5`- nucleotidase activities, important enzymes on parasite/host relationship. The proapoptotic alkaloid, lycorine, and the lactone alkaloid, candimine, caused cell death in the amitochondriate T. vaginalis by a mechanism of action that fails to completely fulfill the criteria for apoptosis. However, some similarities were observed to paraptotic cell death, like intense cytoplasmic periferic vacuolization and nuclear integrity. Since the cytotoxic potential of the alkaloids was moderated (250 μM), the polyamines analogs were chosen to investigate the anti-T. vaginalis activity and to develop semi-synthesis studies with lycorine in order to improve the alkaloid cytotoxicity. Polyamines are simple structured aliphatic amines essential for cell proliferation and differentiation and it has been shown that interfering with their function or biosynthesis the cellular growth can be blocked. Our results showed the synthesis of a series of diamine derivatives, and N-hexadecil-1,4-butanediamine was found to be the most active compound in vitro against T. vaginalis with MIC of 2.5 μg/mL, twice more active in comparison to the reference drug metronidazole. The molecular hybridization of lycorine with diamines was impaired by the unsuccessful synthesis of the lycorine mesilate, a key intermediary on the synthetic route. However, six new lycorine ester derivatives were synthesized.
29

Estudo químico e farmacológico em hippeastrum morelianum lem. e hippeastrum santacatarina (Traub) Dutilh : duas espécies de amaryllidaceae

Giordani, Raquel Brandt January 2007 (has links)
Os produtos naturais têm se destacado ao longo dos anos como princípios ativos eficazes e muitos deles são utilizados até hoje no tratamento de certas doenças. Considerando as informações advindas da medicina popular, o vasto potencial terapêutico de alcalóides e a quimiotaxonomia dos vegetais, a família Amaryllidaceae se candidata a celeiro de novas moléculas bioativas. Verifica-se que os compostos alcaloídicos isolados a partir desta família apresentam atividades biológicas bem reportadas, tais como, antitumoral, antiviral, antimalárica, antiinflamatória e anticolinesterásica. Assim, o objetivo deste trabalho foi o isolamento de alcalóides a partir de Hippeastrum morelianum Lem. e Hippeastrum santacatarina (Traub) Dutilh, além da investigação das atividades antioxidante, anticolinesterásica e antimicrobiana dos produtos isolados, bem como dos extratos obtidos. O material de ambos vegetais foi separado em bulbos, raízes e folhas e submetido à extração ácido-base, clássica para alcalóides.Com auxílio de métodos cromatográficos a partir de H. morelianum foram isolados doze produtos, com destaque para o alcalóide candimina (110 mg) sendo este trabalho a fonte pioneira dos dados espectroscópicos completos deste alcalóide, bem como das primeiras avaliações farmacológicas do mesmo. A partir de H. santacatarina foram isolados três produtos, com destaque para a licorina (100 mg). Todos os extratos avaliados, de ambos vegetais, mostraram potenciais efeitos antioxidante (10 mg/ml) e anticolinesterásico (0,1 mg/ml), porém não antimicrobiano. Quanto aos produtos isolados destaca-se a atividade antioxidante da licorina, verificada pelo método da inativação do radical 2,2-difenil-1-picrilidrazila (DPPH), com IC50: 112,4 μg/ml. Entretanto, no screening de atividade anticolinesterásica todos os isolados de H. morelianum, exceto o produto A12, apresentaram resultado positivo com 5 μg de amostra. Para H. santacatarina, a licorina, assim como os isolados B2 e B3, demonstraram atividade anticolinesterásica, também com 5 μg de amostra. Finalmente, não foi detectada atividade antimicrobiana para licorina e candimina, alcalóides majoritários em suas plantas de origem, até 0,5 mg/ml. / Natural products have been employed over the years as active compounds, and many of them are currently used in the treatment of certain diseases. Considering the information stemming from the popular medicine, the vast therapeutic potential of alkaloids and quimiotaxonomy of plants, the family Amaryllidaceae is known as the source of new bioactive molecules. The alkaloids isolated from this family have many biological activities, such as antitumor, antiviral, antiplasmodial, antiinflammatory and analgesic. Considering the potential pharmacological activity, the aim of this work was to isolate alkaloids from Hippeastrum morelianum Lem. and Hippeastrum santacatarina (Traub) Dutilh. In addition, we investigated the antioxidant, antimicrobial and anticolinesterasic activities of the isolated products and of the extracts. The material of both plants was separated into bulbs, roots and leaves (the last one only from H. morelianum), and it was extracted through the acid-basic method, classical to alkaloids. By chromatographic methods, twelve products were isolated from H. morelianum, with emphasis for the candimine alkaloid (110 mg). Importantly, this is the first report on the complete spectroscopic data and the former evaluations of this alkaloid. Sequentially, tree products were obtained from H. santacatarina, with emphasis on the licorine alkaloid (100 mg). All extracts evaluated, in both plants, demonstrated antioxidant (10 mg/ml) and anticolinesterasic (0,1 mg/ml) potentials, although not antimicrobial. Taking in account the isolated products, it is of interest the antioxidant activity of licorine, revealed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, with IC50: 112,4 μg/ml. On the other hand, all isolates of H. morelianum showed anticolinesterasic activity, except the product A12, at 5 μg. For H. santacatarina, licorine, as well as isolates B2 and B2 showed anticolinesterasic activity, too at 5 μg. Finally, it was not detected antimicrobial activity for the alkaloids licorine and candimine at 0,5 mg/ml or less.
30

Alcalóides bioativos e fenólicos de Hippeastrum solandriflorum (Lindl.) - Amaryllidaceae / Bioactive alkaloids and phenolic Hippeastrum solandriflorum (Lindl.) - Amaryllidaceae

Carvalho, Kaline Rodrigues January 2014 (has links)
CARVALHO, Kaline Rodrigues. Alcalóides bioativos e fenólicos de Hippeastrum solandriflorum (Lindl.) - Amaryllidaceae. 2014. 139 f. Dissertação (Mestrado em química)- Universidade Federal do Ceará, Fortaleza-CE, 2014. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-02T18:29:58Z No. of bitstreams: 1 2014_dis_krcarvalho.pdf: 5041907 bytes, checksum: 07f047c40b792b34c1cb4331f9c7cb28 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-13T23:17:41Z (GMT) No. of bitstreams: 1 2014_dis_krcarvalho.pdf: 5041907 bytes, checksum: 07f047c40b792b34c1cb4331f9c7cb28 (MD5) / Made available in DSpace on 2016-07-13T23:17:41Z (GMT). No. of bitstreams: 1 2014_dis_krcarvalho.pdf: 5041907 bytes, checksum: 07f047c40b792b34c1cb4331f9c7cb28 (MD5) Previous issue date: 2014 / This work describes the phytochemical study of Hippeastrum solandriflorum(Amaryllidaceae)aiming the isolation and structural elucidation of new bioactive compounds, as well as its pharmacological investigation. The chemical investigation realized with the EtOH extract from bulbs, through chromatographic methods, including HPLC (reverse phase), resulting inthe isolation of ten compounds: a furan derivative: 5-(hydroxymethyl)furan-2-carbaldehyde(HS-1), two phenolic derivatives: piscidic acid (HS-2), eucomic acid (HS-3), and seven isoquinoline alkaloids: narciclasin ( HS-4), 2α-hydroxypseudolycorin (HS-5), 10α-hydroxy homolycorin (HS-6), galantamin (HS-7), sanguinin (HS-8),N-oxid galantamin (HS-9) andnarcissidin (HS10). The alkaloids (HS-5) and (HS-6) are being reported for the first time inthe literature, while the other ones have been isolated for the first time in the investigated species. The structures of all isolated compounds were determined based on spectrometricmethods (IR, HRMS, NMR 1H and13C–1D and 2D), besides comparison with published data. The cytotoxic potential of all alkaloids were evaluated against several tumor cell lines:colon (HCT-116), leukemia (HL-60), ovary (OVCAR-8) and brain (SF-295) showing IC50ranging from 0.01 to 35.7 μM. / Este trabalho descreve o estudo fitoquímico de Hippeastrum solandriflorum (Amaryllidaceae) visando o isolamento e elucidação estrutural de novos constituintes químicos bioativos, bem como o estudo farmacológico dos compostos obtidos. A investigação química realizada com o extrato etanólico dos bulbos, através de métodos cromatográficos, incluindo CLAE (fase reversa), resultou no isolamento e identificação de dez substâncias, sendo um derivado do furano: 5-(hidroximetil)furan-2-carbaldeido (HS-1), dois derivados fenólicos: acido piscidico(HS-2), acido eucômico (HS-3) e sete alcaloides isoquinolínicos: Narciclasina (HS-4), 2α-hidroxipseudolicorina (HS-5), 10αhidroxi-homolicorina (HS-6), Galantamina (HS-7), Sanguinina (HS-8),N-oxido galantamina (HS-9), Narcissidina (HS-10). Os alcaloides (HS-5)e (HS-6) esta sendo relatado pela primeira vez na literatura e os demais como sendo inéditos na espécie estudada. As substâncias isoladas tiveram suas estruturas elucidadas por métodos espectrométricos (IV, IES-EM e RMN de1H e13C 1D e 2D), além de comparação com dados da literatura. O potencial citotóxicodos alcaloides isolados foi avaliado frente às linhagens decélulas tumorais humanas: cólon (HCT-116), leucemia (HL-60), ovário (OVCAR-8) e cérebro (SF-295) mostrando valores IC50 variando 0,01–35,7 μM.

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