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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.
11

Tissue culture studies on Peperomia clusifolia Hook. and Strongylodon macrobotrys A. Gray.

Peters, Deborah. January 1982 (has links)
Tissue culture studies were carried out on two ornamental plant species, Strongylodon macrobotrys A. Gray and Peperomia clusifolia Hook. Successful in vitro regeneration of plantlets was achieved in the latter species, using leaf and stem explants. The basal medium of Murashige and Skoog (1962), in combination with various levels of NAA and K, was utilised. Strongylodon proved refractory to both establishment of a thriving callus culture and in vitro formation of roots and shoots. Several media were utilised, Miller's (1963) medium proving the most successful for the production of callus. Different combinations of the growth regulators NAA, IBA, BA and K were used to determine optimum levels of these substances for callus production. Root/shoot induction studies were carried out using the basal medium of Miller (1963) plus various concentrations of IBA in combination with K or BA. Alternatively,the basal medium was used without added growth regulators. Internodes, nodal segments, leaves, pulvini, flower parts and seeds were used in the study. No plantlets were obtained from Strongylodon explants. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1982.
12

Peperomia blanda (Piperaceae): avaliação das atividades antibacteriana e antioxidante

Dignani, Danilo Fuin [UNESP] 15 December 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-15Bitstream added on 2014-06-13T19:53:10Z : No. of bitstreams: 1 dignani_df_me_arafcf.pdf: 773247 bytes, checksum: 12484d76e725fa6e5f7ad83c157f0655 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Peperomia blanda é uma erva rupestre, pequena que cresce em fendas de rochas, nesta espécie foi verificada a presença de componentes voláteis, associações de lignanas, flavonóides, entre outros compostos. Com o objetivo de determinar o potencial biológico de P. blanda, foi estudada a atividade antibacteriana e antioxidante de extratos, frações e substâncias isoladas de suas partes aéreas e raízes, obtidas por maceração a frio. Para determinação da atividade antibacteriana foram utilizadas as técnicas de difusão em agar e microdiluição contra cepas Gram-positivas e Gramnegativas. Para determinação do potencial antioxidante foram realizados os ensaios espectrofotométricos: radical ABTS.+, HOCl, taurina-cloramina e ânion superóxido (O2 ●-), utilizando como padrões a quercetina e cisteína. Na técnica de difusão em agar, 100μL de suspensão bacteriana a concentração de 108 UFC/mL foram semeadas em agar Muller-Hinton com alça de Drigalski. Discos de papel com 10 mm de diâmetros embebidos com 25μL das amostras vegetais foram dispostos na superfície dessas placas. Após incubação a 37ºC por 24 horas em aerobiose foram feitas as leituras dos halos de inibição de crescimento ao redor dos discos, medidos em milímetros. No teste de microdiluição os orifícios das microplacas foram preenchidos com 80μL de caldo de Muller-Hinton, 100μL de soluções da amostra vegetal diluída seriadamente de 1000 a 12,5μg/mL e 20μL da cultura bacteriana a concentração de 107 células/mL. As microplacas foram incubadas a 37ºC durante 24 horas sob condições de aerobiose e posteriormente determinada a leitura da absorbância em leitor de microplaca a 595nm. As amostras vegetais não apresentaram atividade contra nenhuma das bactérias testadas pelo método... / The species of Peperomia blanda is a perennial herb, which grows in small rocks crevices that showed the presence of volatile components, associations of lignans, flavonoids and other compounds. In order to determine the biological potential of P. blanda, we studied the antibacterial and antioxidant activity of extracts, fractions and compounds isolated from its aerial parts and roots, obtained by cold maceration. For determination the antibacterial activity was used agar diffusion and microdilution against strains Gram-positive and Gram-negative. For determination of antioxidant potential were performed spectrophotometric assay: ABTS+ radical, HOCl, taurinecloroamine and superoxide anions (O2 ●-), using quercetin and cysteine as standards. In agar diffusion assay, 100 μL of bacterial suspension in the concentration of 108 CFU/mL were placed on Mueller-Hinton agar with Drigalski. Paper disks with 10 mm in diameter embededd with 25μL samples of vegetables were placed on the surface of these plates. After incubation at 37°C for 24 hours under aerobic conditions were made the readings of the halos of growth inhibition around the disks, measured in millimeters. In the microdilution assay of the microdilutions were filled with 80μL broth Muller-Hinton, 100 μL of the solution plant sample serially diluted from 1000 to 12.5 μg/mL and 20μL of bacterial culture concentration of 107 cells/mL. The microplates were incubated at 37°C for 24 hours under aerobic conditions and thereafter determined reading the absorbance in a microplate reader 595nm.The plant samples did not show any activity against the bacteria tested using agar diffusion. Microdilution bioassay the samples showed the best results against S. aureus... (Complete abstract click electronic access below)
13

Estudo metabolômico e proteômico em Peperomia blanda (Piperaceae)

Felippe, Lidiane Gaspareto [UNESP] 27 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-27Bitstream added on 2014-06-13T19:58:52Z : No. of bitstreams: 1 felippe_lg_me_araiq.pdf: 3785380 bytes, checksum: 174ccb573abb8592b9fe951b97fda87c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O estudo químico das partes aéreas de Peperomia blanda resultou no isolamento de quinze substâncias, incluindo cinco lignanas tetraidrofurâncias (rel-(7R,8S,7’S,8’S)- 4,5,4’,5’-dimetilenodioxi-3,3’-dimetoxi-7,7’-epoxilignana, rel-(7R,8S,7’S,8’S)-4’,5’- metilenodioxi-3,4,5,3’-tetrametoxi-7,7’-epoxilignana, rel-(7R,8S,7’S,8’S)-4-hidroxi- 4’,5’-metilenodioxi-3,5,3’-trimetoxi-7,7’-epoxilignana, rel-(7R,8S,7’S,8’S)-4’-hidroxi- 3,4,5,3’,5’-pentametoxi-7,7’-epoxilignana, rel-(7R,8S,7’S,8’S)-9-hidroxi-4’,5’-metilenodioxi- 3,4,5,3’-tetrametoxi-7,7’-epoxilignana), cinco secolignanas ((2S,3R)-2-metil-3- [bis(4’,5’-metilenodioxi-3’-metoxifenil)metil]butirolactona, rel-(2S,3R)-2-metil-3-[bis (3’,4’,5’-trimetoxifenil)metil]butirolactona, rel-(2R,3R)-2-metil-3-[bis(3’,4’,5’-trimetoxifenil) metil]butirolactona, (2S,3R,5R)-2-metil-3-[5-(3’,4’,5’-trimetoxifenil)-5-(4’’,5’’- metilenodioxi-3’’-metoxifenil)metil]butirolactona, (2R,3R,5R)-2-metil-3-[5-(3’,4’,5’-trimetoxifenil)- 5-(4’’,5’’-metilenodioxi-3’’-metoxifenil)metil]butirolactona), duas flavonas (5-hidroxi-4’,7,8-trimetoxiflavona,5-hidroxi-3’,4’,7,8-tetrametoxiflavona) e três policetídeos (proctoriona C, surinona A, surinona C). As estruturas químicas das substâncias foram determinadas utilizando técnicas espectrométricas, incluindo RMN 1D e 2D. As estereoquímicas relativas das lignanas tetraidrofurânicas e das secolignanas foram determinadas através de experimentos de NOESY 1D e as estereoquímicas absolutas das secolignanas foram determinadas através de dicroísmo circular. Todas as substâncias estão sendo descritas pela primeira vez nessa espécie vegetal, sendo que as lignanas tetraidrofurânicas apresentaram estruturas químicas com estereoquímicas inéditas e as secolignanas haviam sido obtidas... / The phytochemical investigation of aerial parts of Peperomia blanda yielded fifteen compounds, identified as five tetrahydrofuran lignans (rel-(7R,8S,7’S,8’S)- 4,5,4’,5’-dimethylenedioxy-3,3’-dimethoxy-7,7’-epoxylignan, rel-(7R,8S,7’S,8’S)-4’,5’- methylenedioxy-3,4,5,3’-tetramethoxy-7,7’-epoxylignan, rel-(7R,8S,7’S,8’S)-4-hydroxy- 4’,5’-methylenedioxy-3,5,3’-trimethoxy-7,7’-epoxylignan, rel-(7R,8S,7’S,8’S)-4’- hydroxy-3,4,5,3’,5’-pentamethoxy-7,7’-epoxylignan, rel-(7R,8S,7’S,8’S)-9-hydroxy- 4’,5’-methylenedioxy-3,4,5,3’-tetramethoxy-7,7’-epoxylignan), five secolignans ((2S,3R)-2-methyl-3-[bis(4’,5’-methylenedioxy-3’-methoxyphenyl)methyl]butyrolactone, rel-(2S,3R)-2-methyl-3-[bis(3’,4’,5’-trimethoxyphenyl)methyl]butyrolactone, rel- (2R,3R)-2-methyl-3-[bis(3’,4’,5’-trimethoxyphenyl)methyl]butyrolactone, (2S,3R,5R)-2- methyl-3-[5-(3’,4’,5’-trimethoxyphenyl)-5-(4’’,5’’-methylenedioxy-3’’-methoxyphenyl) methyl]butyrolactone and (2R,3R,5R)-2-methyl-3-[5-(3’,4’,5’-trimethoxyphenyl)-5- (4’’,5’’-methylenedioxy-3’’-methoxyphenyl)methyl]butyrolactone), two flavones (5- hydroxy-4’,7,8-trimethoxyflavone, 5-hydroxy-3’,4’,7,8-tetramethoxyflavone) and three polyketides (proctorione C, surinone A, surinone C). The chemical structures were elucidated by interpretation of their spectroscopic data, including 1D and 2D NMR. The relative configurations of tetrahydrofuran lignans and secolignans were determined using NOESY analyses and the absolute configurations were defined by CD spectra. All compounds were described at the first time in this species and all tetrahydrofuran lignans showed novel stereoisomers and the secolignans were previously published as synthetic products. The tetrahydrofuran lignans showed powerful trypanocidal... (Complete abstract click electronic access below)
14

Peperomia pellucida L.(H.B.K.): obtenção tecnológica de formas farmacêuticas

Maria Ferreira da Silva, Rosali 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T16:24:46Z (GMT). No. of bitstreams: 2 arquivo1166_1.pdf: 4907678 bytes, checksum: 022eb5169fb973f57dfb3c991e5484ec (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Peperomia pellucida L. (H.B.K.) é conhecida popularmente como erva-de-jabuti e é usada como antimicrobiano, anti-hipertensivo e anti-inflamatório. Este trabalho teve por finalidade desenvolver tecnologicamente formas farmacêuticas à base de P. pellucida para o tratamento antimicrobiano e cardiovascular, realizando análises anatômica e microquímica das folhas, caracterização físico-química para o pó e para a solução extrativa da planta inteira, análises por espectrofotometria e cromatografia das frações flavonoídica e do extrato bruto, avaliação da sazonalidade e do processo de extração, a avaliação das atividades antimicrobiana e cardiovascular do extrato etanólico, clonagem, avaliação dos diferentes processos de secagem utilizando microscopia eletrônica de varredura e análise térmica, otimização do processo e caracterização físico-química do extrato seco por spray dryer e o desenvolvimento de cápsulas utilizando extrato seco por aspersão de P. pellucida. As características anatômicas e microquímicas foram fundamentais na identificação e caracterização da espécie. A avaliação da sazonalidade indicou que não há influência dos valores de precipitação das chuvas sobre o teor do marcador utilizado para P. pellucida, a 3 ,4 ,7-tri-O-metoxiflavona, nas amostras coletadas nos meses março, maio e julho de 2010. Na variação da concentração do solvente da maceração (50, 70 e 90%), o marcador apresentou um maior valor de teor na concentração de 70% de álcool etílico. O extrato etanólico demonstrou atividade antibacteriana contra Staphylococcus aureus e Pseudomonas aeruginosa. A micropropagação de P. pellucida foi possível utilizando-se gemas axilares jovens. O extrato seco obtido por spray dryer apresentou menor aderência ao equipamento utilizado e partículas esféricas, possibilitando uma melhor fluidez durante o desenvolvimento farmacotécnico-industrial de formas farmacêuticas sólidas. Os estudos de pré-formulação conduziram à definição da forma farmacêutica cápsula. Os resultados obtidos contribuem para a determinação de especificações de uma futura monografia farmacopeica e fornecerão parâmetros para que empreendedores da indústria farmacêutica baseiem-se para a produção de insumos, bem como para o controle de qualidade de intermediários e do produto acabado à base de P. pellucida
15

Bioprospecção em espécies de Piperaceae / Bioprospecting of Piperaceae species

Juliana Beltrame Reigada 14 July 2009 (has links)
O presente trabalho visou a avaliação do potencial antifúngico de extratos brutos das diferentes partes do vegetal (folha, caule e raiz) de espécies de Piperaceae, os quais foram submetidos ao ensaio de bioautografia frente aos fungos Cladosporium cladosporioides e Cladosporium sphaerospermum. Após a triagem biológica, os extratos brutos das espécies Piper mollicomum, Piper marginatum, Peperomia alata e Peperomia glabella foram selecionados para etapas posteriores de fracionamento e purificação, utilizando-se técnicas cromatográficas. O estudo fitoquímico biomonitorado das espécies selecionadas identificou como metabólitos ativos dois cromenos e uma di-hidrochalcona; duas flavanonas e três fenilpropanóides, sendo um de estrutura inédita, denominado marginatumol; dois policetídeos inéditos, alatanona A e alatanona B; quatro acilresorcinóis e quatro secolignanas, incluindo a peperomina G inédita. Todos os metabólitos isolados apresentaram potencial atividade antifúngica, sendo os policetídeos alatanona A e alatanona B os mais ativos, com atividade superior às substâncias controle (nistatina e miconazol). Assim, os dados obtidos neste estudo permitiram descrever diferentes classes de produtos naturais a partir de uma coleção de extratos de espécies de Piperaceae, com potencial para estudos de relações estrutura-atividade. / The present study was addressed to evaluate the antifungal activity of crude extracts from Piperaceae species in which different parts of the plant (leaves, stems and roots) were assessed by means of bioautography against Cladosporium cladosporioides and Cladosporium sphaerospermum. After antifungal assay, the extratcs from Piper mollicomum, Piper marginatum, Peperomia alata and Peperomia glabella displayed higher growth inhibitory potency and thus were selected for further fractionation and purification using chromatographic techniques. Such dereplication using the bioautographic assay yielded two chromenes and one dihydrochalcone; two flavanones and three phenylpropanoids, including the novel compound marginatumol; two new polyketides, alatanone A and alatanone B; four acylresorcinols and four secolignans, including the novel peperomin G, respectively. The bioautography indicated potential antifungal activity for all isolated metabolites and compounds alatanone A and alatanone B were found the most active in comparison to positive controls (nystatin and miconazole). The bioprospecting approach was proven to be very effective when the isolation of bioactive compounds from a collection of crude extracts is concerned, although not necessarily unraveling the major biosynthetic pathways in each plant species.
16

Phylogeny and divergence time estimation of Piperales / コショウ目の系統と分岐年代推定

Kobayashi, Yukihiro 23 May 2022 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24079号 / 理博第4846号 / 新制||理||1693(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 田村 実, 教授 工藤 洋, 教授 松下 智直 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
17

Systematic and Evolution of Peperomia subgenus Tildenia (Piperaceae)

Symmank, Lars 20 October 2011 (has links) (PDF)
The present study deals with the largely unknown Peperomia subgenus Tildenia. Chapter 1 focuses on the South American centre of Tildenia biodiversity. Initially a general rectified description of Peperomia subgenus Tildenia is presented based on the latest molecular analyses. Fourteen new species are described together with two formerly published varieties that are raised to species rank. Furthermore, for one name, basionym rejection and lectotypification are proposed. All valid species from the South American centre of diversity are treated in a phylogenetic framework. A comparable study of the North American centre of diversity is presented in Chapter 2 including a key to all Tildenia species from Mexico and Central America and the description of thirteen new species (one former variety). The new descriptions within this study doubles the species number of subgenus Tildenia. Chapter 3 is a biogeographical study comprising the whole distribution area revealing the place of origin and the age of Peperomia subgenus Tildenia. The appearance of the major lineages of the subgenus is examined against the background of orogeny and climate changes in the respective distribution areas, to retrace the evolutional driving forces of this plant group. In Chapter 4 Tildenia is used as a model group for the characterisation of a new nuclear single copy gene applicable for general use for phylogentic resoltution on species level and below.
18

Systematic and Evolution of Peperomia subgenus Tildenia (Piperaceae)

Symmank, Lars 07 July 2011 (has links)
The present study deals with the largely unknown Peperomia subgenus Tildenia. Chapter 1 focuses on the South American centre of Tildenia biodiversity. Initially a general rectified description of Peperomia subgenus Tildenia is presented based on the latest molecular analyses. Fourteen new species are described together with two formerly published varieties that are raised to species rank. Furthermore, for one name, basionym rejection and lectotypification are proposed. All valid species from the South American centre of diversity are treated in a phylogenetic framework. A comparable study of the North American centre of diversity is presented in Chapter 2 including a key to all Tildenia species from Mexico and Central America and the description of thirteen new species (one former variety). The new descriptions within this study doubles the species number of subgenus Tildenia. Chapter 3 is a biogeographical study comprising the whole distribution area revealing the place of origin and the age of Peperomia subgenus Tildenia. The appearance of the major lineages of the subgenus is examined against the background of orogeny and climate changes in the respective distribution areas, to retrace the evolutional driving forces of this plant group. In Chapter 4 Tildenia is used as a model group for the characterisation of a new nuclear single copy gene applicable for general use for phylogentic resoltution on species level and below.
19

2-Acil-cicloexano-1,3-dionas de Peperomia trineura (Miq.) / 2-Acylcyclohexane-1,3-diones from Peperomia trineura (Miq.)

Ferreira, Edgard Antonio 18 September 2009 (has links)
O extrato bruto da planta inteira (Peperomia trineura) foi submetido à cromatografia de adsorção em sílica gel, cromatografia em camada delgada preparativa (CCDP) e CLAE semipreparativa, resultando no isolamento de cinco policetídeos inéditos em função do comprimento ou presença da insaturação na cadeia alquílica. A elucidação estrutural destes policetídeos foi realizada com base nas analises espectroscópicas de RMN 1D e 2D, infravermelho e espectrometria de massas de baixa e alta resolução. As frações provenientes do extrato bruto foram testadas frente a duas linhagens de células leucêmicas (K-562 e Nalm 6), apresentando atividades consideráveis. Já os policetídeos tiveram seu potencial antifúngico avaliado frente a duas espécies de fungos fitopatogênicas - Cladosporium cladosporioides e C. sphaerospermum - e apresentaram atividade fraca e média variando de acordo com suas estruturas. / The crude extract of whole plant (Peperomia trineura) was subjected to adsorption chromatography on silica gel, preparative thin-layer chromatography (CCDP) and semi-preparative HPLC, resulting in the isolation of five novel polyketides with variable chain lenght or presence of unsaturation in the alkyl chain. The structural elucidation of these compounds was based on spectroscopic techniques for 1D and 2D NMR, infrared and low and high resolution mass spectrometry. The fractions from the crude extract were tested against the two leukemic cell lines (K-562 and Nalm 6), showing considerable activities. The polyketides were evaluated against the phytopathogenic fungi - Cladosporium cladosporioides and C. sphaerospermum - and displayed low and medium activity.
20

2-Acil-cicloexano-1,3-dionas de Peperomia trineura (Miq.) / 2-Acylcyclohexane-1,3-diones from Peperomia trineura (Miq.)

Edgard Antonio Ferreira 18 September 2009 (has links)
O extrato bruto da planta inteira (Peperomia trineura) foi submetido à cromatografia de adsorção em sílica gel, cromatografia em camada delgada preparativa (CCDP) e CLAE semipreparativa, resultando no isolamento de cinco policetídeos inéditos em função do comprimento ou presença da insaturação na cadeia alquílica. A elucidação estrutural destes policetídeos foi realizada com base nas analises espectroscópicas de RMN 1D e 2D, infravermelho e espectrometria de massas de baixa e alta resolução. As frações provenientes do extrato bruto foram testadas frente a duas linhagens de células leucêmicas (K-562 e Nalm 6), apresentando atividades consideráveis. Já os policetídeos tiveram seu potencial antifúngico avaliado frente a duas espécies de fungos fitopatogênicas - Cladosporium cladosporioides e C. sphaerospermum - e apresentaram atividade fraca e média variando de acordo com suas estruturas. / The crude extract of whole plant (Peperomia trineura) was subjected to adsorption chromatography on silica gel, preparative thin-layer chromatography (CCDP) and semi-preparative HPLC, resulting in the isolation of five novel polyketides with variable chain lenght or presence of unsaturation in the alkyl chain. The structural elucidation of these compounds was based on spectroscopic techniques for 1D and 2D NMR, infrared and low and high resolution mass spectrometry. The fractions from the crude extract were tested against the two leukemic cell lines (K-562 and Nalm 6), showing considerable activities. The polyketides were evaluated against the phytopathogenic fungi - Cladosporium cladosporioides and C. sphaerospermum - and displayed low and medium activity.

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