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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.
91

Antiproliferative effect of the Chinese medicinal herb, Centipeda minima. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Bioactivity-guided isolation of SFE oil led to the identification of another sesquiterpene lactone, 6-O-angeloylprenolin, containing the bioactive alpha, beta-unsaturated cyclopentenone. MTT results showed that CNE cells were more susceptible to 6-O-angeloylenolin than the normal Hs68 cells. Besides, the inhibitory effect of 6-O -angeloylenolin on the CNE cells was slightly stronger than that of cisplatin, the positive control, albeit statistical insignificance. / Both volatile oils prepared by supercritical fluid extraction (SFE) and steam distillation (SD) were evaluated for their anti-NPC potential. Results showed that SFE oil was much stronger than that of SD oil. SFE oil significantly inhibited the growth of CNE cells by dysfunctioning the mitochondria and activating caspases. Gas chromatography-mass spectrometry analysis revealed that the responsible principals in the SFE oil were likely homologues of sesquiterpene lactones. / Centipeda minima (L.) A. Br. (Compositae), a Chinese medicinal herb, is used to treat nasopharyngeal carcinoma (NPC) in the Chinese folk. However, there is a paucity of information on its anticancer activities. In particular, both of its anti-NPC potential and the potent constituents remain elusive. / In this study, the n-hexane fraction of C. minima showed broad spectrum of inhibitory effects on five human cancer cell lines, including the breast carcinoma MCF7 cells, the prostate carcinoma PC-3 cells, the hepatocellular carcinoma Hep G2 cells, the nasopharyngeal cancer CNE cells and the acute promyelocytic leukemia HL-60 cells, with IC 50 values ranging from 6.1 to 47.3 mug/mL. Bioactivity-guided separation of the n-hexane fraction using the CNE cells as the cellular system led to the isolation of a sesquiterpene lactone, 2beta-(isobutyryloxy)florilenalin (IF), which contained the bioactive alpha-methylene-gamma-lactone ring. IF significantly induced CNE cell death with an IC50 value of 3.1 mug/mL. Despite this potency, its effect on the normal Hs68 cells was much weaker, with an IC50 value larger than 50 mug/mL. Its inhibitory effect on the CNE cells ascribed to apoptotic induction as evidenced by the cumulation of sub-G1 cell population, DNA fragmentation and nuclear condensation, caspase-3 activation and poly (ADP-ribose) polymerase (PARP) cleavage. Mechanistic study showed that both extrinsic and intrinsic apoptotic pathways were activated. In the extrinsic pathway, IF activated caspase-8, which further induced the activation of caspase-3 and caspase-7. In the intrinsic pathway, IF regulated the expressions of Bcl-2 family proteins, followed by depletion of mitochondrial membrane potential (Delta&PSgr;m), the release of cytochrome c to cytosol, the activation of caspase-9 and other downstream caspases, and finally the induction of apoptosis. / Mechanistic investigation showed that 6-O-angeloylenolin caused cell cycle arrest at S and G2/M phases and induced apoptosis in CNE cells. For the cell cycle arrest, a sharp decrease was found in the expressions of cyclin D1, cyclin D3, cdc25c, and p-cdc25c, with concomitant decrease in CDK4, cyclin A, cyclin E, p-Rb(Ser780), p21Waf1/Cip1, cdc2 and p-cdc2. For the induction of apoptosis, externalization of phosphatidylserine and depletion of Delta&PSgr;m prior to the detection of sub-G1 peak were found. Other apoptotic features including the presence of apoptotic bodies, the activation of caspase-3 activity and the cleavage of PARP were observed. Activation of caspase-8 and caspase-10 was detected. Besides, 6-O -angeloylenolin induced the release of cytochrome c and AIF to cytosol. The former formed apoptosome with caspase-9, further activated the downstream caspase-3 and caspase-7 and cleaved PARP, while the latter was translocated into the nucleus and caused large-scale DNA fragmentation. Failure of the pan-caspase inhibitor, z-VAD-fmk, to interrupt the apoptotic induction by 6-O-angeloylenolin suggested that caspase-independent pathway was involved. 6-O-Angeloylenolin was able to activate Akt, ERK and JNK pathways. But only with the addition of JNK inhibitor (SP600125), significant suppression of the 6-O-angeloylenolin-induced apoptosis was observed, suggesting the involvement of the JNK pathway in the apoptotic pathway. Taken together, this study provided a better mechanistic insight into the potential application of 6-O-angeloylenolin as a candidate for NPC treatment. / Overall, this study revealed that two sesquiterpene lactones, including IF and 6-O-angeloylenolin were found to be responsible for the potent anti-NPC effect of C. minima. This study reiterates the notion that Chinese medicinal herbs traditionally applied to cancer treatment may be good sources of anticancer drug discovery, and sesquiterpene lactone may be a group of noteworthy lead compounds displaying anti-NPC potential. / Su, Miaoxian. / Adviser: Hau Yin Chung. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 100-113). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
92

Avalia??o qu?mica e biol?gica do Jambu (Acmella oleracea L.) seco com ar frio e liofilizado / Chemical and biological evaluation Jambu (Acmella oleracea L.) dry with cold air and lyophilized

BARBOSA, Alan Franco 15 December 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-09-12T17:41:07Z No. of bitstreams: 1 2016 - Alan Franco Barbosa.pdf: 6969234 bytes, checksum: 6f0ea0da3698193a91ae661b3c8aee8e (MD5) / Made available in DSpace on 2017-09-12T17:41:07Z (GMT). No. of bitstreams: 1 2016 - Alan Franco Barbosa.pdf: 6969234 bytes, checksum: 6f0ea0da3698193a91ae661b3c8aee8e (MD5) Previous issue date: 2016-12-15 / CAPES / CNPq / FAPERJ / The chemical and biological properties of Jambu, as well as the evaluation of the stability of spilanthol and the procedures of isolation this amide by solvents extraction are described. Were determined the amino acid profile, fatty acids, minerals, and free polyphenols, and total antioxidant activity (DPPH and ABTS) by the processes of drying with cold air and lyophilization. Adsorption isotherms were constructed using the set of experimental data of eight mathematical models. Lyophilized capitula, leaves and stems of Jambu were extracted with methanol at 100 ?C, and 10 MPa, and analyzed by LC-MS and NMR spectroscopy. The effect of methanol extract, and of fractions obtained by partitions with hexane and dichloromethane of methanol extracts, of the Jambu on the tyrosinase enzyme such as the antimicrobial activity front against of Micrococcus luteus and Lactobacillus casei were evaluated. The activation index of NKCC2 phosphorylation was evaluated by Western blotting. The rate of aquaporin 2 apical expression was analysed by confocal laser microscopy. Jambu dryed by cold air showed higher content of nutrient, except for the mineral content, and antioxidant capacity compared to lyophilized Jambu. At all evaluated temperatures, the model of Peleg presented the best adsorption isotherms of Jambu dryed by cold air. Spilanthol concentrations in capitula, leaves and stems were 16.5, 0.344 and 0.241 mg/g dry weight. The methanol extract from Jambu and the hexane fraction (84.28 % of spilanthol) were able to activate oxidant activity of the tyrosinase enzyme. On the other hand, the dichloromethane fraction (about 100 % spilanthol) showed strong inhibitory effect of tyrosinase enzyme in the first 10 min. There was no antimicrobial activity of methanol extract and hexane fraction about L. casei. But the hexane fraction created inhibition zone on M. luteus. Induced inhibition of cAMP by spilanthol modulates negatively the urine-concentrating mechanisms. It is concluded that Jambu subjected to the drying process with cold air offers better chemical quality and antioxidant capacity. The major component, espilantol, present mainly in inflorescences, does not change with extreme storage conditions. The methanolic extract of Jambu strongly activates the enzyme tyrosinase, whereas the dichloromethane fraction inhibits the tyrosinase. The hexanic fraction inhibits Micrococcus luteus growth and espilantol inhibits the production of cAMP, contributing to its application in drugs with diuretic function. / Esta tese teve por objetivo avaliar as propriedades qu?micas e biol?gicas do Jambu, bem como avaliar a estabilidade do espilantol e isolar esta amida por extra??o com solventes. Foram determinados o perfil de amino?cidos, ?cidos graxos, minerais, polifen?is totais e livres e a capacidade antioxidante (DPPH e ABTS) do Jambu pelos processos secagem com ar frio e liofiliza??o. As isotermas de adsor??o foram constru?das usando o conjunto de dados experimentais de 8 modelos matem?ticos. Cap?tulos, folhas e hastes liofilizados de Jambu foram extra?dos com metanol a 100 ?C e press?o de 10 MPa e analisados por CL-EM e RMN. Avaliaram-se os efeitos do extrato metan?lico e de fra??es obtidas com hexano e diclorometano do Jambu sobre a enzima tirosinase e atividade antimicrobiana frente ao Micrococcus luteus e o Lactobacillus casei. A fosforila??o de NKCC2 foi avaliada como ?ndice da sua ativa??o atrav?s de Western blotting. A taxa de express?o apical aquaporina 2 foi analisada por microscopia confocal a laser. O Jambu seco com ar frio apresentou maior teor dos nutrientes avaliados, com exce??o do teor de minerais, e maior capacidade antioxidante em rela??o ao Jambu liofilizado. O modelo de Peleg, em todas as temperaturas avaliadas, apresentou melhores isotermas de adsor??o de umidade do Jambu seco com ar frio. As concentra??es de espilantol nos cap?tulos, folhas e hastes foram de 16,5, 0,344 e 0,241 mg/g do peso seco. O extrato metan?lico de Jambu, bem como a fra??o hex?nica (84,28 % de espilantol) foram capazes de ativar a enzima tirosinase, por outro lado, a fra??o obtida com diclorometano (cerca de 100 % espilantol) mostrou forte efeito de inibi??o da enzima tirosinase nos primeiros 10 min. N?o foi observada a??o antimicrobiana do extrato metan?lico e fra??o hex?nica sobre L. casei, por?m, a fra??o hex?nica criou halo de inibi??o sobre M. luteus. O espilantol inibiu a produ??o de cAMP, modulando negativamente os mecanismos de concentra??o de urina. Conclui-se que o Jambu submetido ao processo de secagem com ar frio ofereceu melhor qualidade qu?mica e capacidade antioxidante. O componente majorit?rio, espilantol, presente sobretudo nas infloresc?ncias, n?o se altera com condi??es extremas de armazenamento. O extrato metan?lico de Jambu ativa fortemente a enzima tirosinase, enquanto que a fra??o diclorometano inibe a tirosinase. J? a fra??o hex?nica inibe o crescimento Micrococcus luteus e o espilantol inibe a produ??o de cAMP, contribuindo para sua aplica??o em f?rmacos com fun??o diur?tica.
93

The molecular phylogeny of Pectis L. (Tageteae, Asteraceae), with implications for taxonomy, biogeography, and the evolution of C4 photosynthesis

Hansen, Debra Rae 18 November 2013 (has links)
This study examines the evolutionary history of Pectis L., a neotropical genus of ~90 species of xeric-adapted, herbaceous, annuals and perennials. Pectis is rare among the Asteraceae, as it uses C₄ photosynthesis, a complex suite of traits that concentrates carbon around Rubisco. Plants with C₄ photosynthesis do well in environments of high light and high heat, and the C₄ syndrome is thought to have evolved as a response to such environments. Pectis is most diverse in Mexico, the Caribbean Islands, and South America, and its distribution mirrors the disjunctions of patches of desert, thornscrub, coastal plains, savanna, and openings in seasonally-dry tropical forests and oak-pine woodlands. Vicariance and long-distance dispersal theories can explain the patchy distribution of xeric-adapted plants, as well as the origin of Caribbean species. To answer evolutionary questions about a group, one must understand how its members are related. The most comprehensive taxonomic treatment of Pectis is over 100 years old, and includes only North American species. Recent revisions still leave half the species unassigned to section. Molecular studies have found Pectis sister to, or encompassing, the genus Porophyllum. To infer evolutionary relationships between and within Pectis and Porophyllum, DNA from the nuclear and chloroplast genomes of 78 Pectis and 22 Porophyllum species were sampled, sequenced, and analyzed. The molecular phylogeny was used to suggest updated sections based on monophyletic groups. To infer the photosynthetic pathway of Pectis and Porophyllum species, carbon isotope ratios were obtained from 62 Pectis and 18 Porophyllum species. The timing and location of the evolution of Pectis and Porophyllum has implications for the evolution of C₄ photosynthesis. The carbon isotope data were combined with the phylogeny to determine the extent and direction of the evolution of C₄ photosynthesis, and the timing of its evolution was inferred from a fossil-calibrated analysis using chloroplast data from species across the Asteraceae. Distribution data was combined with the Pectis phylogeny to answer questions regarding the biogeographical history of Pectis, including questions regarding its disjuncted distribution, the timing of the evolution of desert species, and the timing and pattern of dispersal to and from the Caribbean Islands. / text
94

Patterns of Genetic Variation in Rosette-Brachyglottis are Inconsistent with Current Species Delimitation

Millar, Timothy Robert January 2014 (has links)
Brachyglottis (Asteraceae) is a genus of approximately 30 species in the Brachyglottidinae, a recently recognised sub-tribe of tribe Senecioneae. Within Brachyglottis is a clade of five species of rosette-forming herbs: B. bellidioides, B. haastii, B. lagopus, B. southlandica and B. traversii. A sixth species, B. saxifragoides, has recently been synonymised with B. lagopus. The rosette-Brachyglottis have historically been recognised as a taxonomically problematic group because species overlap in both morphology and geographical distribution. A recent molecular study of rosette-Brachyglottis using AFLP data indicated that genetic distances among populations of rosette-Brachyglottis in the South Island appear to be correlated with geographical distance between populations rather than taxonomic identification. This is problematic as the currently described rosette-Brachyglottis species have overlapping ranges which implicitly hypothesises reproductive barriers other than geographic distance. We conducted an investigation into the species delimitation of rosette-Brachyglottis with the aim of answering two related questions: Does the current delimitation of rosette-Brachyglottis accurately reflect patterns of genetic similarity? Do the patterns of genetic structure in rosette-Brachyglottis support the presence of multiple biological species? A total of 46 populations of rosette-Brachyglottis were represented in this study. Herbarium specimens collected from these populations were identified following the taxonomic treatment of Allan (1961). Twenty one discrete and numerical morphological characters were measured from herbarium specimens including those collected for this study and previously collected herbarium specimens. Morphological dissimilarity of 354 herbarium specimens was investigated by performing a PCoA on Gower’s pairwise morphological distances among individuals. The pattern of genetic similarity was explored using DNA fragment length variation in nine markers for 273 individuals and this resulted in a total 177 unique alleles. Bayesian clustering analysis was performed on this data set using STRUCTURE, in addition, pairwise genetic distances were calculated among individuals and populations using Jaccard and Nei’s dissimilarity coefficient’s respectively. Jaccard genetic distances among individuals were analysed using PCoA and Nei’s genetic distances among populations were analysed using a Neighbour-Net analysis. The relationship between pairwise genetic and geographic distances among populations was analysed using a combination of linear regression and a Mantel Test. The pattern of morphological similarities among specimens was generally congruent with the currently delimited species in rosette-Brachyglottis. However, many morphologically intermediate specimens confound the recognition of distinct morphological entities. Comparison of patterns of genetic similarity and the current morphologically-based species delimitation showed that the delimitation does not accurately reflect the genetic structure of rosette-Brachyglottis. Furthermore, patterns of genetic dissimilarity did not indicate discrete genetic groups at the individual or population levels. The finding of incongruence between patterns of genetic and morphological similarity and absence of morphologically or genetically discrete groups suggests that rosette-Brachyglottis are best considered a single, yet morphologically diverse, biological species. In addition genetic structure within this species appears to be primarily driven by geographical isolation.
95

Revisión sistemática, análisis cladístico y biogeográfico del género Ophryosporus Meyen (Asteraceae, Eupatorieae, Critoniinae)

Plos, Anabela 01 March 2013 (has links)
Revisión Sistemática El género Ophryosporus Meyen pertenece a la subtribu Critoniinae R. M. King & H. Rob., tribu Eupatorieae Cass., e incluye 41 especies sudamericanas distribuidas en Argentina, Brasil, Bolivia, Chile, Ecuador y Perú. Ophryosporus fue descripto en el año 1834 por Meyen, quien incluyó sólo la especie, O. triangularis Meyen, basada en materiales chilenos. Si bien posteriormente se describieron más especies originalmente como Ophryosporus, una gran parte de las que actualmente están incluidas en este género fueron descriptas inicialmente como Eupatorium L. En 1906, B. L. Robinson realizó la primera revisión del género e incluyó 17 especies y una variedad. Este mismo autor identificó dos secciones: Euophryosporus y Ophryochaeta. En 1972, King & Robinson, ampliaron el concepto del género al incluir una sección del género Piqueria Cav. y un género monoespecífico (Trychinolepis B. L. Rob.). Como resultado de la presente revisión sistemática, todas las especies de Ophryosporus fueron descriptas e ilustradas, en muchos casos por primera vez aportándose también mapas de distribución, datos ecológicos y fenológicos, información sobre usos medicinales y compuestos químicos asociados, así también como una clave para la identificación de las especies dentro del género que hasta el momento no se había realizado. Además, se seleccionaron 12 lectotipos y se resolvieron complejos problemas nomenclaturales. Análisis Cladístico Para corroborar la monofilia de Ophryosporus y establecer las relaciones entre sus especies y con las especies pertenecientes al grupo externo, se realizó un análisis cladístico considerando las 41 especies del género. Se obtuvieron 61 caracteres cualitativos, de los cuales 24 fueron vegetativos y 37 reproductivos. Para la conformación del grupo externo, se eligieron especies pertenecientes a los géneros Critonia P. Browne, Cronquistianthus R. M. King & H. Rob., Koanophyllon Arruda, (los tres pertenecientes a la subtribu Critoniinae) y Fleischmannia Sch. Bip. (subtribu Fleischmanniinae). Se comprobó que el género Ophryosporus es monofilético y el clado se encuentra definido por la presencia de involucros de hasta 8 filarios, dispuesto en 1 o 2 series de filarios, hasta 8 flores por capítulo, apéndices conectivales de las anteras nulos o muy rudimentarios, ramas del estilo clavadas y por células del carpopodio heteromorfas. Se comprobó la inaplicabilidad de las secciones propuestas por B. L. Robinson al actual concepto de Ophryosporus. Si bien se obtuvieron dos clados claramente definidos, los mismos no están debidamente sustentados. Este hecho, sumado a que muchos caracteres surgen en paralelo en ambos clados, imposibilita la creación de secciones en Ophryosporus. Análisis Biogeográfico Se realizó un análisis biogeográfico utilizando el análisis de dispersión y vicarianza, DIVA, que incluyó tanto a las especies de Ophryosporus como a las del grupo externo. Nueve áreas de endemismos fueron consideradas para el análisis biogeográfico. De acuerdo a los resultados, se postula el origen del género Ophryosporus en los Andes Húmedos Centrales-Norte de Sudamérica. Posteriormente, se habrían producido dispersiones hacia las áreas Andes Secos Centrales-Sur y Chaco. Los eventos vicariantes principales se habrían producido en el área ancestral Desierto peruano-chileno / Pacífico Ecuatorial Seco y en el área ancestral Andes Húmedos Centrales-Norte / Andes Secos Centro-Sur. De acuerdo al registro fósil de tribus cercanas a Eupatorieae, conjuntamente con los datos aportados por el análisis de las tasas evolutivas del gen ndhF podría sugerirse que el origen de Ophryosporus habría tenido lugar entre los 7,4 y 14,8 Ma. / Systematic Revision Ophryosporus Meyen belongs to the subtribe Critoniinae R. M. King & H. Rob, tribe Eupatorieae Cass., and includes 41 South American species, distributed in Argentina, Bolivia, Brazil, Chile, Ecuador and Peru. Ophryosporus was first described in 1834 by Meyen. In 1906, B. L. Robinson carried out the first revision of the genus, with the inclusion of 17 species and one variety. Also, the autor defined two sections: Euophryosporus and Ophryochaeta. In 1972, King & Robinson expanded the genus concept by the inclusion of a section of the genus Piqueria Cav. and a monospecific genus (Trychinolepis B. L. Rob.). As a result of the present systematic revision, all the species of Ophryosporus were described in detail and illustrated, in many cases for the first time. Distribution maps, ecological and phenological data, information about medicinal uses and chemistry compounds associated is also provided. A key for the identification of the species of the genus is presented for the first time. Moreover, twelve lectotypes were selected and complex nomenclatural problems were resolved. Cladistic Analysis To corroborate the monophyly of Ophryosporus and to establish the relationships among its species, a cladistic analysis was made, considering all the 41 species of the genus. For the analysis, 61 qualitative characters, 24 vegetative and 37 reproductive characters were used. For the conformation of the outgroup, species belonging to the genus Critonia P. Browne, Cronquistianthus R. M. King & H. Rob., Koanophyllon Arruda (the three from Critoniinae) and Fleischmannia Sch. Bip. (subtribe Fleischmanniinae) were chosen. Ophryosporus was found monophyletic, defined by the presence of up to 8 phyllaries, arranged in one or two series, up to 8 florets by capitula, anthers without conectival appendices or, if present, very rudimentary, style branches clavate and by heteromorphical carpopodial cells. The infrageneric sections proposed by B. L. Robison are inapplicable to the actual concept of Ophryosporus. Even with the results with two clades, these clades lack of appropiate support. Biogeographical Analysis A biogeographical analysis was performed using DIVA, with all the species of Ophryosporus and outgroups. Nine endemism areas were considered for the biogeographical analysis. Ophryosporus would have originated in the Humid Central-North Andes of South America, with subsequent dispersions to the Dry Central-South Andes and Chaco. The main vicariant events would have occured on the ancestral area of the Peruvian Chile Desert and Ecuatorial Dry Pacific, and in other event, on the area of Humid Central-North Andes and Dry Central-South Andes. According with the fossil record of of other subtribes of Eupatorieae, based on data of the evolutionary rate of the gen ndhF the origin of Ophryosporus could be suggested between 7,4 to 14,8 Ma.
96

Produção de biomassa e teor de cumarina em folhas de guaco (Mikania laevigata Sch. Bip. ex Baker) em diferentes idades da planta / Biomass production and coumarin content in different ages of guaco leaves (Mikania laevigata Sch. Bip. Ex Baker)

Santos, Dayane Graziella Pereira de Oliveirs dos [UNESP] 29 February 2016 (has links)
Submitted by DAYANE GRAZIELLA PEREIRA DE O. DOS SANTOS null (daygrazi@hotmail.com) on 2016-05-23T04:00:20Z No. of bitstreams: 1 Dayane pdf.pdf: 1015868 bytes, checksum: 6aca3f66299016c2bab0b0b8f46c4cb4 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-05-25T17:15:55Z (GMT) No. of bitstreams: 1 santos_dgpo_me_bot.pdf: 1015868 bytes, checksum: 6aca3f66299016c2bab0b0b8f46c4cb4 (MD5) / Made available in DSpace on 2016-05-25T17:15:55Z (GMT). No. of bitstreams: 1 santos_dgpo_me_bot.pdf: 1015868 bytes, checksum: 6aca3f66299016c2bab0b0b8f46c4cb4 (MD5) Previous issue date: 2016-02-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A espécie Mikania laevigata Sch. Bip. ex Baker, popularmente conhecida como guaco, pertence à família Asteraceae, é originária da região sul do Brasil e está entre as plantas medicinais adotadas pelo Sistema Único de Saúde do Brasil. M. laevigata é uma opção agrícola promissora no cultivo das medicinais, estando acessível ao pequeno produtor, tendo em vista a crescente demanda do mercado consumidor brasileiro por fitoterápicos. Uma vez que as plantas medicinais são classificadas como produtos naturais, a lei permite que sejam cultivadas e comercializadas desde que se atinja o padrão de qualidade necessário. O presente trabalho foi instalado e conduzido na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas - UNESP, Campus de Botucatu, Estado de São Paulo. O objetivo desta pesquisa foi avaliar a produtividade de biomassa e teor de cumarina do guaco colhido em diferentes idades da planta. Foi observada maior produtividade para as variáveis avaliadas aos onze meses de idade do guaco, obtendo 0,96 t ha-1 de matéria seca de folha sendo que não houve diferença estatística quanto ao teor de cumarina aos 7, 9, e 11 meses de idade de Mikania laevigata. Nas condições em que foi realizada a pesquisa, o maior rendimento de biomassa x teor de cumarina foi obtido aos 11 meses de idade do guaco, o qual possibilitou o melhor resultado para o rendimento extrativo de cumarina em folhas secas. / The species Mikania laevigata Sch. Bip. ex Baker, popularly known as guaco, belongs to the Asteraceae family and it is native to southern Brazil it is among the medicinal plants adopted by the Unified Health System in Brazil (SUS). M. laevigata is a promising option in agricultural cultivation of medicinal plants and is accessible to small farmers, in view of the growing demand of the Brazilian market for herbal medicines. Since medicinal plants are classified as natural products, the law allows them to be grown and marketed it they achieve the required quality standards. This work was conducted at the Lageado Experimental Farm, Faculty of Agricultural Sciences - UNESP, Botucatu, State of São Paulo. The objective of this research was to evaluate the productivity of biomass and coumarin content of guaco harvested at different ages of the plant. It was observed higher productivity for the variables evaluated at eleven months of guaco, obtaining 0.96 t ha-1 of dry leaf and there was no statistical difference in the coumarin content at 7, 9, and 11 months of age Mikania laevigata. The conditions under which the survey was conducted, the higher biomass yield x coumarin content of guaco was obtained at 11 months of age, which enabled the best result for the extraction yield of coumarin in dry leaves. / CNPq: 133395/2014-6
97

Composição química e análise biológica de espécies do gênero baccharis / Chemical constituents and biological analyses of Baccharis species

Oliveira, Simone Quintana de January 2008 (has links)
O gênero Baccharis, Asteraceae, compreende mais de 500 espécies distribuídas exclusivamente no continente Americano. No Brasil estão descritas 120 espécies, sendo que, no Rio Grande do Sul, há relatos de setenta espécies distribuídas desde a região serrana até o litoral. Conhecidas popularmente como carquejas, muitas destas plantas são utilizadas na medicina popular, apesar da sinonímia popular comum e da difícil identificação botânica. Visando ampliar os estudos químicos e biológicos com espécies do gênero Baccharis este trabalho teve como objetivos prosseguir os estudos fitoquímicos de B. articulata, B. cylindrica B. spicata, B. trimera e B. usterii, visando a diferenciação química das mesmas através de cromatografia em camada delgada, avaliar a atividade antibacteriana de B. articulata, B. spicata, B. trimera e B. usterii, isolar e identificar os compostos presentes nas frações n-BuOH de B. articulata e B. usterii e, ampliar as investigações quanto à atividade antioxidante dessas espécies. Os resultados obtidos permitiram detectar diferenças qualitativas no perfil químico das amostras testadas através da cromatografia em camada delgada e propor metodologia para sua diferenciação química. A partir das frações n-BuOH de B. articulata e B. usterii foram isoladas sete substâncias codificadas como: Ba III (4’-O-β-D-glicopiranosil-3,5- dimetóxi-benzil-tetrahidro-2H-pirano-2-il-acetil-carbonato), Ba IV (4’-O-β-Dglicopiranosil- 3,5-di-metóxi-fenil-metanol), Ba V, Ba VI, BuF1 (ácido 4,5-O-[E]-dicafeoilquínico), BuF2 (7-hidróxi-5,4’-di-metóxi-flavona) e BuT1, respectivamente. As substâncias Ba V, Ba VI e BuT1 encontram-se em elucidação estrutural. Quanto à atividade antioxidante verificou-se que as frações n-BuOH de B.articulata e B. usterii apresentaram efeito antioxidante na concentração de 1,25 μg/mL e mantiveram este efeito no decorrer do ensaio TRAP. As substâncias isoladas a partir da fração n- BuOH de B. articulata não apresentam potencial antioxidante na mesma intensidade que a referida fração. No índice TAR, verificou-se a reatividade instantânea das frações n-BuOH destas espécies, bem como da substância BuF1. Quanto a capacidade protetora contra a peroxidação lipídica, as frações n-BuOH, as substâncias Ba III, Ba IV, Ba V, as sub-frações fenólica e terpênica (B. usterii) e a substância BuF1 foram eficientes em proteger as células da peroxidação. Quanto à atividade antibacteriana verificou-se que a fração n-BuOH de B. spicata (concentração 1 mg/mL) foi ativa frente a S. aureus, E. coli, E. faecalis e E. faecium (CBM 50 mg/mL). A fração n-BuOH de B. usterii na mesma concentração apresentou efeito contra S. aureus (CBM 25 mg/mL), E. faecalis e E. faecium (CBM 50 mg/mL). Os extratos brutos (1 mg/mL) de B. trimera e B. usterii foram ativos frente a S. aureus (CBM 12,5 mg/mL e 25 mg/mL, respectivamente).O extrato bruto e as frações de B. articulata não apresentaram atividade frente aos microrganismos testados. / The Baccharis genus, Asteraceae, is native to America, encompassing nearly 500 species of which approximately 120 are found in Brazil. Around 70 species were described in the State of Rio Grande do Sul. Popularly known as “carquejas”, aerial parts of Baccharis species are used in traditional medicine in spite of the difficult botanical differentiation among them. In order to continue the phytochemical and biological studies about Baccharis species, the objectives of this thesis were to propose a chemical differentiation by thin-layer chromatography of B.articulata, B. cylindrica B. spicata, B. trimera and B. usterii, to evaluation the antibacterial activity of B. articulata, B. spicata, B. trimera and B. usterii, the isolation and identification of compounds from n-BuOH fractions of B. articulata and B. usterii and to evaluate their antioxidant activity. It was possible to propose a methodology to differentiate the Baccharis species studied herein by thin-layer chromatography. From n-BuOH fractions of B. articulata and B. usterii were isolated seven compounds: Ba III (4-O-β- D-glucopiranosyl-3,5-dimethoxibenzyl-tetrahydro-2H-pyran-2-yl-acetyl-carbonate), Ba IV (4-O-β-D-glucopiranosyl-3,5-dimethoxyphenil-methanol), Ba V, Ba VI, BuF1 (4,5- O-[E]-dicaffeoylquinic acid), BuF2 (7-hydroxy-5,4’-dimethoxy-flavone) e BuT1. Structural elucidation of Ba V, Ba VI and BuT1 compounds are in course. Regarding the antioxidant activity, it was verified that the n-BuOH fractions from B.articulata and B. usterii showed antioxidant effect at concentration of 1.25 μg/mL, which was maintained during the analyzed period on TRAP experiment. The isolated compounds did not show the same antioxidant potential than the n-BuOH fractions. TAR index showed the instantaneous reactivity of the n-BuOH fractions of these species and BuF1 compound. Regarding the capacity of to protect the cells from lipid peroxidation, the n-BuOH fractions, Ba III, Ba IV, Ba V compounds, the phenolic and terpenic sub-fractions (B. usterii) and BuF1 compound were efficient to protect the cells from lipid peroxidation. In relation to antibacterial activity it was verified that the n-BuOH fraction of Baccharis spicata (1 mg/mL) was effective against S. aureus, Escherichia coli, Enterococcus faecalis, and Enterococcus faecium (MBC 50 mg/mL). The n-BuOH fraction of Baccharis usterii (1 mg/mL) was effective against S. aureus (MBC 25 mg/mL), Enterococcus faecalis, and Enterococcus faecium (MBC 50 mg/ml). The crude extract of Baccharis trimera (1 mg/mL) showed activity against S. aureus (MBC 25 mg/mL and 12.5 mg/mL, respectively). Extract and fractions from B. articulata were not active against the microorganisms tested.
98

Comunidades de tripes (Insecta : Thysanoptera) em flores e ramos, com ênfase em Asteraceae no Parque Estadual de Itapuã, Viamão, RS

Cavalleri, Adriano January 2005 (has links)
A ordem Thysanoptera reúne cerca de 5.500 espécies descritas, das quais, mais de 2.000 estão registradas para a região Neotropical. Apesar da grande diversidade de tripes existente no Brasil - que engloba quase 10% das espécies do mundo inteiro - há uma lacuna no conhecimento dessa fauna em ambientes naturais e de sua biologia e ecologia. Os poucos estudos já realizados sugerem que a família Asteraceae apresenta uma tisanopterofauna mais rica que as demais e que flores e ramos são utilizados diferencialmente pelas espécies de tripes. Este estudo objetivou contribuir para o levantamento da tisanopterofauna nativa e averiguar a flora explorada por estes insetos, quanto à utilização de flores e ramos e sua ocorrência em Asteraceae e outras famílias. A área de estudo foi o Parque Estadual de Itapuã (PEI), Viamão (50º 50’- 51º 05’W e 30º 20’- 30º 27’ S), RS. Quatro saídas de campo foram realizadas de junho de 2003 a abril de 2004. Foram determinadas três trilhas de aproximadamente 500 m em diferentes tipos de vegetação. As trilhas estabelecidas foram a da praia da Pedreira (TP) (mata baixa e vegetação rupestre), a do morro do Araçá (TA) (vegetação rupestre, vassourais e mata baixa) e a do morro da Grota (TG) (vegetação rupestre, butiazais e vassourais). Cada uma destas foi dividida em quatro subáreas, de igual extensão. A cada saída foram sorteadas duas destas subáreas, nas quais foram amostrados aleatoriamente três indivíduos de Asteraceae e três de qualquer outra família. De cada indivíduo era retirado um ramo com flores (F) e um sem flores (R). Cada ramo escolhido constituiu uma unidade amostral (UA). Para o total de 279 UAs, foram coletados 1.695 indivíduos - 870 adultos (583 ♀ e 287 ♂) e 825 larvas - de 31 espécies de Thysanoptera, em 19 gêneros e três famílias. Os Terebrantia representaram mais de 90% dos adultos e 76% dos imaturos coletados e compreenderam a maioria das espécies (26). Dentre as famílias, a mais rica e abundante foi Thripidae, com 757 indivíduos e 23 espécies. Frankliniella (9 spp.), Heterothrips (3 spp.) e Neohydatothrips (3 spp.), foram os gêneros mais ricos. Frankliniella foi também o mais abundante, perfazendo cerca de 64% do total da amostra. Os tisanópteros mais comuns foram Frankliniella rodeos e Paraleucothrips minusculus Johansen, 1983, com 363 e 92 indivíduos coletados. Os Índices de Shannon-Wiener (H’) e de dominância de Simpson (D) estimados para a tisanopterofauna do PEI foram de 2,19 e 0,211, respectivamente. Foram coletados 690 adultos e 572 larvas de tripes em F, distribuídos em 29 espécies. Já em R foram capturados 180 adultos e 253 imaturos, sendo registradas 22 espécies. O Índice de Shannon-Wiener aponta uma maior diversidade em R (H’ = 2,33) do que em F (H’ = 2,01), pois a dominância foi notadamente maior em F (D = 0,255) do que em R (D = 0,133) devido a grande abundância de Frankliniella spp. nos mesmos. Em 46 das 61 espécies vegetais coletadas foi constatada a presença de tisanópteros. Entre as famílias de plantas com maior número de espécies associadas com tripes, destacam-se Asteraceae (22), Myrtaceae (4) e Rubiaceae (4). Das 31 espécies de tripes identificadas, 19 ocorrem em Asteraceae e quatro foram registradas exclusivamente nesta família. Observou-se diferenças marcantes nos valores de H’ e D entre a tisanopterofauna habitante de asteráceas (H’ = 1,68; D = 0,311) e aquela das demais famílias (H’ = 2,11; D = 0,178).
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O gênero Pterocaulon Ell. (Asteraceae) no Rio Grande do Sul: aspectos taxônomicos, palinológicos e fitoquímicos

Lima, Luis Fernando Paiva January 2006 (has links)
Resumo não disponível
100

Estudo do mecanismo de ação da atividade acaricida de Calea serrata (Asteraceae) em Rhipicephalus (Boophilus) microplus e da sua toxicidade em roedores

Ribeiro, Vera Lucia Sardá January 2012 (has links)
O extrato n-hexano de Calea serrata demonstrou atividade acaricida contra larvas de Rhipicephalus (Boophilus) microplus e R. sanguineus. A enzima acetilcolinesterase (AChE), responsável por hidrolisar a acetilcolina nas sinapses colinérgicas, tem sido alvo de pesticidas e sua inibição pelos organofosforados levam à paralisia e morte de artrópodes. O uso intensivo de acaricidas / inseticidas tem provocado resistência em artrópodes, a qual pode estar relacionada com maior atividade de enzimas de detoxicação, como a glutationa-S-transferase (GST). O objetivo do presente estudo foi avaliar a atividade acaricida do componente isolado do extrato n-hexano, o precoceno II, e do óleo essencial de C. serrata, assim como, determinar a composição química do referido óleo. Com intuito de compreender o mecanismo de ação acaricida do extrato n-hexano de C. serrata, foi investigado o efeito deste extrato sobre a atividade in vitro da AChE em larvas de R. microplus e em estruturas cerebrais de ratos Wistar machos, bem como sobre a modulação da atividade da GST em larvas de R. microplus. O óleo essencial e o precoceno II, o composto isolado, mostraram atividade larvicida. O óleo essencial apresentou diferentes sesquiterpenos em sua constituição química, além de precoceno II. O extrato nhexano de C. serrata inibiu significativamente a atividade in vitro da AChE em larvas de R. microplus e em estruturas cerebrais de ratos. O extrato n-hexano de C. serrata inibiu significativamente a atividade in vitro da GST. Compostos do extrato n-hexano de C. serrata podem ser potenciais inibidores de AChE e de GST, os quais podem contribuir para a sua toxicidade para os carrapatos. Considerando que o aumento da atividade da GST poderia reduzir a eficiência de carrapaticidas, é possível supor que C. serrata possa ser usada como um adjuvante no controle de R. microplus. Os resultados obtidos também suportam a possibilidade de que a inibição da acetilcolinesterase seja um possível mecanismo de ação do extrato n-hexano de C. serrata. / It has been demonstrated that the n-hexane extract of Calea serrata had acaricidal activity against larvae of R. microplus and R. sanguineus. Acetylcholinesterase (AChE), an enzyme that hydrolyses acetylcholine at cholinergic synapses, is a target for pesticides and its inhibition by organophosphates leads to paralysis and death of arthropods. Extensive uses of acaricides/inseticides have induced resistance in arthropods, which can be related to higher activity of detoxification enzymes, such as glutathione-S-transferase (GST).The aims of the present study were to evaluate the acaricide activity of isolated constituent of n-hexane extract, the precocene II, and the essential oil of C.serrata, in addition to determine the chemical composition of essential oil. In order to understand the mechanism of the acaricidal action of C. serrata n-hexane extract, we investigated the effect of this extract on in vitro anticholinesterase activity of larvae from R. microplus and in brain structures of male Wistar rats, as well as, we investigated the effect of C. serrata on GST activity of larvae from R. microplus.The essential oil and the isolated compound, precocene II, showed larvicidal action. Several sesquiterpenes were detected in the essential oil of C. serrata. The n-hexane extract significantly inhibited in vitro acetylcholinesterase activity in R. microplus larvae and rat brain structures. The n-hexane extract of C. serrata inhibited significantly GST activity. Compounds of n-hexane extract from C. serrata may be potential inhibitors of AChE and GST, which may contribute to its tick toxicity. Considering that higher GST activities would reduce the efficiency of the pesticides, we can also suppose that C. serrata may be at least used as an adjuvant in tick control. The results support that inhibition of acetylcholinesterase is a possible mechanism of action of hexane extract at C. serrata.

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