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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.
141

Atividade gastroprotetora do óleo essencial de Citrus lemon (Rutaceae), de seus componentes principais Limoneno e β-pineno e do óleo essencial de Croton cajucara (Euphorbiaceae) /

Rozza, Ariane Leite. January 2009 (has links)
Resumo: O presente trabalho teve como objetivos testar a atividade gastroprotetora de úlceras gástricas e mecanismos de ação do óleo essencial de Croton cajucara (CC), do óleo essencial de Citrus lemon (CL) e dos constituintes majoritários de CL, que são o Limoneno (L) e o β- pineno (P). Assim, foram realizados modelos de indução de úlcera gástrica por etanol absoluto para CL, L, P e CC e por droga anti-inflamatória não esteroidal (Indometacina) para CL, L e P. Todos os resultados foram expressos em média  epm (p<0.05). No modelo de indução de úlceras por etanol absoluto, a área das lesões (mm2) foi 0.00  0.00** para CL, L e CC (100% de gastroproteção), 73.20  27.32 para P, que não exerceu efetiva gastroproteção (53.26%), 22.27  8.21** para o controle positivo (85.80%) e 156.60  36.30 para o veículo. O escore microscópico indicou excelente preservação da mucosa por CL**, L*** e CC***. A área de marcação imunoistoquímica para heat shock protein 70 foi estatisticamente maior nos grupos CL, L, P e CC e para peptídeo intestinal vasoativo foi maior nos grupos CL, L e P. Os níveis de glutationa (GSH, em μg/ml) foram 1182.00  52.47** para CL, 1316.6  67.75** para L, 1286.5  93.15* para CC, 1195.60  37.57** para o controle positivo, 982.8  79.07** para o veículo e 1704.30 ± 149.03 para o grupo branco. Na indução de úlcera por Indometacina, CL exerceu gastroproteção de 98.3% com área de lesão (mm2) 0.85 ± 0.85**, L exerceu gastroproteção de 50.1% (área lesada 24.34 ± 5.3**), P não exerceu efetivo efeito gastroprotetor (37%) com área lesada 30.66 ± 4.22, contra 66.6% de gastroproteção e 16.27 ± 4.49** para o controle positivo e 48.72 ± 6.64 de área lesada para o veículo. CL administrado isoladamente manteve os níveis gástricos de PGE2 (em ng/ml) em 18,25 ± 2,58, mesmo com a administração em conjunto com ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to test the gastroprotective activity and the mechanism of action of the essential oil of Croton cajucara (CC), the essential oil of Citrus lemon (CL) and the majoritary substances present in CL, wich are Limonene (L) and β-pinene (P). Then, gastric ulcers in rats were induced by absolute ethanol after oral treatment with CL, L, P and CC and by indometacin (non-steroidal anti-inflamatory drug) after oral treatment with CL, L and P. All results were expressed in mean  standard error mean (p<0.05). In ethanol-induced gastric ulcer, the ulcer area (mm²) were 0.00  0.00** for CL, L and CC (100% of gastroprotection), 73.20  27.32 for P (53.26% of the ulcer area was reduced, however there was no effective gastroprotection), 22.27  8.21** for the positive control (85.80%) and 165.60  36.30 for the vehicle. The microscopic score showed gastric mucosa was preserved in CL**, L*** and CC***. The marked area for heat shock protein 70 (HSP-70) and vasoactive intestinal peptide (VIP) immunohistochemistries were statistically augmented in CL, L and P groups. The levels of glutathione (GSH, μg/ml) were 1182.00  52.47** for CL, 1316.6  67.75** for L, 1286.5  93.15* for CC, 1195.60  37.57** for the positive control, 982.8  79.07** for the vehicle and 1704.30 ± 149.03 for the sham group. In the indomethacin-induced gastric ulcer, CL offered 98.3% gastroprotection (ulcer area 0.85 ± 0.85**), L offered 50.1% gastroprotection (ulcer area 24.34 ± 5.3**), P did not show gastroprotective effect (37%) and presented ulcer area 30.66 ± 4.22. The positive control offered 66.6% gastroprotection (ulcer area 16.27 ± 4.49**) and the vehicle presented ulcer area 48.72 ± 6.64. CL was able to maintain the PGE2 levels (ng/ml) 18.25 ± 2.58 near to sham group (21.14 ± 1.14), even with indomethacin (PGE2 inhibitor) administration (17.89 ± 1.55), compared with ... (Complete abstract click electronic access below) / Orientador: Cláudia Helena Pellizon / Coorientador: Clélia Akiko Hiruma-Lima / Banca: Maria de Lourdes Mendes Vicentini Paulino / Banca: Lourdes Campaner dos Santos / Mestre
142

Efeito de extratos vegetais e óleos essenciais de espécies nativas de Pernambuco sobre o ácaro rajado Tetranychus urticae Koch (Acari : Tetranychidae) / Effect of plant extracts and essentail oils of native species of Pernambuco on the two-spotted spider mite Tetranychus urticae (Acari : Tetranychidae)

PONTES, Wendel José Teles 01 February 2006 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-12-01T12:21:44Z No. of bitstreams: 1 Wendel Jose Teles Pontes.pdf: 861006 bytes, checksum: 961fa7bfa809cad4e7404803afd41260 (MD5) / Made available in DSpace on 2016-12-01T12:21:44Z (GMT). No. of bitstreams: 1 Wendel Jose Teles Pontes.pdf: 861006 bytes, checksum: 961fa7bfa809cad4e7404803afd41260 (MD5) Previous issue date: 2006-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The present work has the objective to verify the chemical composition and the bio activity of essential oils form fruits and leaves of Protium heptaphyllum and of X. sericea, and the fresh and old oil resins of Protium bahianum, as well as the effect of plant extracts of Croton sellowii, C. micans, C. rhamnifolium, C. jacobinensis and Xylopia sericea, all native species of Pernambuco, on the mite T. urticae. Major constituent identified in the essential oil of fruits from P. heptaphyllum is α-terpene (47.57 %) whereas in the leaves are the sesquiterpenes 9-epi-cariofileno (21.35 %), trans-isolongyfolanone (10.70 %) and 14-hydroxy-9-epi-cariofilene (16.70 %). The fruit oil is more efficient against mites in comparison with the leaf oil. Both oils show a property of mortality and deterrence in oviposition in the highest concentration (10μL L-1 air) and only the essential oil of fruits induces repellence on T. urticae. The essentialoils of the two resins of Protium bahianum were analysed. The old resin shows a high percentage of oxygen containing sesquiterpenes (85.40 %) with high predominance of β-(Z)-santalol acetate (83.08 %). No sesquiterpene was found in the essential oil of the fresh resin, which comprises basically monoterpenes of hydrocarbons (42.37 %) and oxygenated monoterpenes (27.71 %), from which α-phellandrene (13.86 %) and 4-terpineol (7.44 %) arte the major components, respectively. The oils show toxicity against ants, but only the essentialoil of the fresh resin show repellence. Of the studied Croton extracts, the one of the leaves of C. sellowii is the most efficient, causing 69 % of mortality and only the leaf extract of C. jacobinensis is inactive. Mites’ fecundity was affected and all extract show repellence in the concentration of 1%. The major compounds in the essential oil of fruits of X. sericea are β-pinene and α-pinene. The leaf oil is comprised basically by cubenol followed by α-epi-muurolol. Hexane extracts of fruits and the essential oils of fruits and leaves show toxicity against mites. The xylopic acid even not provoking mortality reduces mites’ fecundity. / O presente trabalho tem por objetivo verificar a composição química e a bioatividade dos óleos essenciais de frutos e folhas de Protium heptaphyllum e de Xylopia sericea, e os óleos das resinas velha e fresca de Protium bahianum, bem como o efeito de extratos vegetais de Croton sellowii, C. micans, C. rhamnifolius, C. jacobinensis e X. sericea, todas estas espécies nativas de Pernambuco, sobre o ácaro rajado Tetranychus urticae. O constituinte majoritário identificado no óleo essencial dos frutos de P. heptaphyllum foi α-terpineno (47,57%), enquanto que nas folhas foram os sesquiterpenos 9-epi-cariofileno (21,35%), trans-isolongifolanona (10,70%) and 14-hidroxi-9-epi-cariofileno (16,70%). O óleo dos frutos foi mais eficiente contra o ácaro, comparado com o óleo das folhas. Ambos os óleos apresentaram mortalidade e efeitos sobre a oviposição na maior concentração (10μL / L de ar) e apenas o óleo essencial dos frutos provocou repelência à T. urticae. Os óleos essenciais dos dois exsudatos resinosos de P. bahianum foram analisados. A resina velha mostrou alta percentagem de sesquiterpenos, contendo oxigênio (85,40%) com alta predominância de β-(Z)-santalol acetato (83,08 %). Contudo, nenhum sesquiterpeno foi detectado no óleo essencial de resina fresca, sendo este constituído basicamente de monoterpenos hidrocarbonados (42,37%) e monoterpenos oxigenados (27,71%), dos quais α-phellandrene (13,86 %) e 4-terpineol (7,44 %) foram os componentes majoritários, respectivamente. Os óleos mostraram ação fumigante, mas somente o óleo essencial de resina fresca foi repelente. Dentre os extratos de Croton estudados, verificou-se que o extrato de folhas de C. sellowii apresentou melhor performance, causando 69% de mortalidade e apenas o extrato de folhas de C. jacobinensis foi inativo. A fecundidade dos ácaros também foi afetada e todos os extratos foram repelentes na concentração de 1%. Os compostos majoritários encontrados no óleo essencial dos frutos de X. sericea foram β-pineno e α-pineno. O óleo das folhas foi majoritariamente constituído por cubenol seguido por α-epi-muurolol. Os extratos hexânicos de frutos e os óleos essenciais de frutos e folhas foram tóxicos ao ácaro rajado. O ácido xylópico, apesar de não ter provocado mortalidade, reduziu a fecundidade do ácaro.
143

Estudo comparativo de óleos essenciais de espécies de croton do estado de Sergipe

Santana, Valéria Santos 24 October 2011 (has links)
This paper reports the study of composition and variation of the chemical components of essential oils of Croton species of Sergipe emphasizing its importance chemotaxonomy. Essential oils from fresh aerial parts obtnained by hydrodistillation from samples of Croton blanchetianus (CB-GA), C. campestris (CC-AML), C. heliotropiifolius collected at different locations in the Sergipe (CH-SG1, CH-SG2, CH-GA, and CH-AML), C. pedicellatus (CP-SI), C. tetradenius (CT-SG) and seven other unidentified taxa, called CSP1-CPS7, were analyzed by GC-MS and GC-FID, such analysis revealed a highly variable chemical composition. It were identified 131 components by comparing the retention indices and mass spectra of compounds with literature data and NIST and Willey mass spectra libraries. With the chemical analysis of oil of Croton were established correlations between the taxa of C. heliotropiifolius, which can be differentiated by using their main chemical markers: (E)-caryophyllene and bicyclogermacrene. For comparative analysis of the chemical composition of essential oils of Croton species, chemometric tools as Principal Component Analysis (PCA) and hierarchic Cluster Analysis (HCA) was applied, by which it was possible to differentiate the components of the essential oil of aerial parts of Croton species grouped by class of compounds according to their biosynthetic origin (monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, phenylpropanoids and derivatives of fatty acids). With this analysis it was possible to form three groups (I, II and III), corroborating the comparative analysis of chromatographic profiles. To our knowledge, this is the first report on the chemical composition of essential oils of C. pedicellatus and C. tetradenius. / Este trabalho relata o estudo da composição e variação dos componentes químicos do óleo essencial das espécies de Croton do estado de Sergipe dando ênfase a sua importância quimiotaxonômica. Os óleos essenciais das partes aéreas frescas obtidos por hidrodestilação das amostras de Croton blanchetianus (CB-GA), C. campestris (CC-AML), C. heliotropiifolius coletadas em diferentes localidades do Estado (CH-SG1, CH-SG2, CH-GA, CH-SI e CH-AML), C. pedicellatus (CP-SI), C. tetradenius (CT-SG) e outros sete táxons ainda não identificados denominados (CSP1-CPS7) foram analisados por CG-EM e CG-DIC revelando uma composição química bastante variável. Foram identificados 131 componentes, baseados nos índices de retenção e na comparação de seus espectros de massas com os da literatura e com as bibliotecas de espectros de massas Willey e NIST. Com a análise química dos óleos de Croton foram estabelecidas correlações entre os táxons de C. heliotropiifolius, os quais foram diferenciados dos demais mediante a utilização de seus marcadores químicos principais: (E)-cariofileno e biciclogermacreno. Para as análises comparativas da composição química dos óleos essenciais das espécies de Croton aplicaram-se ferramentas quimiométricas de Análise dos Componentes Principais (ACP) e Análise de Agrupamentos Herarquicos (AAH), pelas quais foi possível diferenciar os componentes do óleo essencial das partes aéreas das espécies de Croton agrupados por classe de compostos de acordo com sua origem biossintética (hidrocarbonetos monoterpênicos, monoterpenos oxigenados, hidrocarbonetos sesquiterpênicos, sesquiterpenos oxigenados, fenilpropanóides e derivados de ácidos graxos). Com essas análises foi possível a formação de três grupos (I, II e III), corroborando com as análises comparativas dos perfis cromatográficos. Ao nosso conhecimento, este é o primeiro relato sobre a composição química dos óleos essenciais de C. pedicellatus e C. tetradenius.
144

Atividade biológica “in vitro” de extratos de Commiphora leptophloeos (Mart.) JB Gillett, Ziziphus joazeiro Mart., Croton heliotropiifolius Kunth, Abarema cochliacarpos (Gomes) Barneby & Grimes e Eugenia uniflora L. contra ixodídeos, culicídeos e nematoides gastrintestinais de pequenos ruminantes

TENÓRIO, Rodrigo Ferreira Lima 24 February 2017 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2018-02-22T13:54:27Z No. of bitstreams: 1 Rodrigo Ferreira Lima Tenorio.pdf: 1676555 bytes, checksum: 5aef9244e7a794028037da3695731eab (MD5) / Made available in DSpace on 2018-02-22T13:54:27Z (GMT). No. of bitstreams: 1 Rodrigo Ferreira Lima Tenorio.pdf: 1676555 bytes, checksum: 5aef9244e7a794028037da3695731eab (MD5) Previous issue date: 2017-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The use of medicinal plants is an alternative for pest control, as they provide chemical compounds with potential ectoparasiticidal action. Thus, the objective of this study was to evaluate the in vitro biological activity of extracts of Commiphora leptophloeos (Mart.) JB Gillett, Ziziphus joazeiro Mart., Croton heliotropiifolius Kunth, Abarema cochliacarpos (Gomes) Barneby & Grimes and Eugenia uniflora L. against ixodids, culicidae and small ruminant gastrointestinal nematodes. The tickcide activity was evaluated against Anocentor nitens by the technique of immersion of engorged females. Concentrations of 100 % and 50 % of the hydroalcoholic extracts of the leaves of C. leptophloeos, C. heliotropiifolius and Z. joazeiro and distilled water as negative control were used. In the assay with Culicids Aedes (stegomyia) aegypti third instar larvae were exposed to concentrations of 30 mg / mL, 20 mg / mL and 10 mg / mL of leaf extracts of C. leptophloeos and C. heliotropiifolius, and for Z. joazeiro 30 mg / mL, 1 mg / mL and 0.5 mg / mL according to a methodology recommended by the World Health Organization. An biological larvicide Bacillus thuringiensis sorovar israelensis at concentrations of 0.06 ppm and 0.37 ppm was used as positive control and a negative control with dechlorinated water. Under the same conditions, the ethanolic extract of A. cochliacarpos stem bark at a concentration of 10 mg / mL was tested, and the industrial larvicide Pyriproxyfen at a concentration of 0.002 g / L and distilled water were used as positive control and negative control respectively. The antihelminthic activity against gastrintestinal helminths of small ruminants was evaluated for the ethanolic extract of A. cochliacarpos stem bark (10 %, 25 % and 50 % concentrations) and of the aqueous extract of E. uniflora leaves (concentrations of 20 %), determined by the calculation of percentages of larvae reduction per gram of faeces. Negative controls were used with distilled water and positive controls with Ivermectin 1 % and Albendazole 5 %. The species C. leptophloeos was effective at all concentrations tested against A. nitens, and the species Z. joazeiro and C. heliotropiifolius demonstrated efficacy only at the concentration of 100 %. In the A. aegypti assay, the highest mortality rates were obtained at the highest concentrations tested, being 66.5 % for C. leptophloeos, 92.75 % for Z. joazeiro and 33.75 % for C. heliotropiifolius. With the extract of A. cochliacarpos (10 mg / mL) the mortality rate was 34.75 %. In the larvae reduction per gram of faeces, larvae of genus Haemonchus, Trichostrongylus and Oesophagostomum were identified, obtaining a highly effective reduction for the 25 % and 50% concentrations of A. cochliacarpos against the three genera. The aqueous extract of E. uniflora (20 %) had no effect on the reduction of the number of larvae of said gastrointestinal nematodes. It is concluded that hydroalcoholic extracts of the leaves of C. leptophloeos, Z. joazeiro and C. heliotropiifolius present biological activity against A. nitens, and the ethanolic extract of the stem bark of A. cochliacarpos shows a better mortality activity than conventionally commercial larvicides used against A. aegypti larvae. The aqueous extract of the leaves of E. uniflora at the concentration of 0.2 g / mL is not present enough to promote reduction of larvae per gram of feces. / O uso de plantas medicinais é uma alternativa para o controle de pragas, pois fornecem compostos químicos com potencial ação ectoparasiticida. Desta forma, objetivou-se no presente estudo avaliar a atividade biológica “in vitro” de extratos de Commiphora leptophloeos (Mart.) JB Gillett, Ziziphus joazeiro Mart., Croton heliotropiifolius Kunth, Abarema cochliacarpos (Gomes) Barneby & Grimes e Eugenia uniflora L. contra ixodídeos, culicídeos e nematoides gastrintestinais de pequenos ruminantes. A atividade carrapaticida foi avaliada contra Anocentor nitens pela técnica de imersão de fêmeas ingurgitadas. Foram utilizadas concentrações de 100 % e 50 % dos extratos hidroalcoólicos das folhas de C. leptophloeos, C. heliotropiifolius e Z. joazeiro e água destilada como controle negativo. No ensaio com culicídeos, segundo metodologia preconizada pela Organização Mundial da Saúde com larvas de terceiro estádio de Aedes (stegomyia) aegypti expostas à concentrações de 30 mg / mL, 20 mg / mL e 10 mg / mL dos extratos das folhas de C. leptophloeos e C. heliotropiifolius, e 30 mg / mL, 1 mg / mL e 0,5 mg / mL para Z. joazeiro, e como controle positivo larvicida biológico Bacillus thuringiensis sorovar israelensis nas concentrações de 0,06 ppm e 0,37 ppm, e controle negativo com água declorada. Nas mesmas condições, testou-se o extrato etanólico da casca do caule de A. cochliacarpos na concentração de 10 mg / mL, tendo como controle positivo o larvicida industrial Pyriproxyfen na concentração de 0,002 g / L e controle negativo água destilada. Pelo cálculo dos percentuais de redução de larvas por grama de fezes, o mesmo extrato de A. cochliacarpos foi avaliado contra helmintos gastritestinais de pequenos ruminantes (concentrações a 10 %, 25 % e 50 %), e o extrato aquoso das folhas de E. uniflora (concentrações a 20 %). Utilizaram-se controles negativos com água destilada e controles positivos com Ivermectina 1 % e Albendazole 5 %. Contra A. nitens, a espécie C. leptophloeos mostrou-se eficaz em todas as concentrações testadas, e as espécies Z. joazeiro e C. heliotropiifolius demonstraram eficácia apenas na concentração de 100 %. No ensaio com A. aegypti, as mais elevadas taxas de mortalidade foram obtidas nas maiores concentrações testadas, sendo de 66,5 % para C. leptophloeos, 92,75 % para Z. joazeiro e de 33,75 % com C. heliotropiifolius. Com o extrato de A. cochliacarpos (10 mg / mL) a taxa de mortalidade foi de 34,75 %. No teste de redução do LPG, identificaram-se larvas dos gêneros Haemonchus, Trichostrongylus e Oesophagostomum, obtendo-se redução altamente efetiva para as concentrações de 25 % e 50 % de A. cochliacarpos contra os três gêneros. O extrato aquoso de E. uniflora (20 %) não apresentou efeito sobre a redução do número de larvas dos referidos nematoides gastrintestinais. Conclui-se que os extratos hidroalcoólicos das folhas de C. leptophloeos, Z. joazeiro e C. heliotropiifolius apresentam atividade biológica contra A. nitens, e o extrato etanólico da casca do caule de A. cochliacarpos demonstra melhor atividade de mortalidade que larvicidas comerciais convencionalmente utilizados contra larvas de A. aegypti. O extrato aquoso das folhas de E. uniflora na concentração de 0,2 g / mL não se apresenta suficiente para promover a redução de larvas por grama de fezes.
145

Potencial antibacteriano do óleo essencial de Croton tetradenius (Baill.) frente a bactérias uropatógenas e sinergismo com antibióticos

Siqueira, Ingrid Borges 31 July 2017 (has links)
Urinary tract infections (UTIs) are the most common infections experienced by humans. It is mainly found in the female gender and it is generally associated with symptomatic and asymptomatic bacteriuria. The most commom etiological agent of UTIs is Escherichia coli (approximately 90% of cases); However, other Gram-negative and some Gram-positive bacterias may be involved in the infectious process. Facing the current scenario of antibiotic resistant strains selection, the study of alternative methods for the control of infectious diseases has been the object of several research groups. Therefore, the purpose of this work was to test different genotypes of Croton tetradenius essential oil (EO) against strains of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. Initially, the spectrum of the oils activity against these microorganisms was tested by the agar diffusion method. In order to evaluate the antimicrobial activity, the Minimal Inhibitory Concentration (MIC) and Minimum Bactericidal Dose (MBD) of the oils against the selected strains were determined followed by a test to determine the microorganisms growth curve. The Checkboard Method was used to evaluate the synergism between the essential oils and the antibiotics ciprofloxacin and meropenem against the bacterias used. The cytotoxicity of the essential oils was verified by the MTT method (3- (4,5-dimethylthiazol-2-il) -2,5-diphenyltetrazolium bromide), against mouse fibroblast lineage L929. Then it was observed that C. tetradenius genotypes showed activity against the tested microorganisms. In addition, the inhibition halos found higher than 9 mm and the only microorganism that was not inhibited by any of the genotypes was P. aeruginosa. Also the MIC for the microorganisms tested ranged from 1.4 to 11.3 mg / mL, while the MBD varied from 2.8 mg / mL to 11.3 mg / mL. By increasing the concentration of essential oil in the culture medium the lag phase raised while the growth rate decreased as well as the maximal DO reached by cultures. Essential oils in combination with antibiotics showed a synergistic effect in most combinations, being indifferent only to E.coli when combined with EO and ciprofloxacin. The tested oils had no cytotoxicity at concentrations of 50 and 100 ug / ml. / As infecções do trato urinário (ITU’s) estão entre as doenças mais frequentes no ser humano, sendo mais comuns em mulheres e podendo apresentar-se como assintomáticas ou sintomáticas. O principal agente etiológico das ITU’s é a bactéria Escherichia coli (aproximadamente 90% dos casos); porém, outras bactérias Gram-negativo e algumas Gram-positivo podem estar envolvidas no processo infeccioso. Diante do cenário atual do desenvolvimento de linhagens resistentes a antibióticos, o estudo de métodos alternativos para o controle de doenças infeciosas tem sido objeto de vários grupos de pesquisa. Portanto, este trabalho teve como objetivo testar dois diferentes genótipos do óleo essencial de Croton tetradenius frente à linhagens de Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae e Pseudomonas aeruginosa. Inicialmente, o espectro de atividade dos óleos foi testado pelo método de difusão em ágar. Para avaliação da atividade antimicrobiana foram determinadas a Concentração Inibitória Mínima (CIM) e a Dose Bactericida Mínima (DBM) dos óleos frente às cepas selecionadas, seguido de teste para determinação da curva de crescimento dos microrganismos. Utilizou-se o Método de Checkboard para avaliar o sinergismo entre os óleos essenciais e os antibióticos ciprofloxacino e meropenem frente às bactérias utilizadas. A citotoxicidade dos óleos essenciais foi verificada através do método MTT (brometo de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazólio) frente a fibroblastos L929. Observou-se que os genótipos de C. tetradenius apresentaram atividade contra os microrganismos testados com formação de halos de inibição superiores a 9,0mm e o único microrganismo que não foi inibido por nenhum dos genótipos foi P. aeruginosa. A CMI para os microrganismos testados variou de 1,4 a 11,3mg/mL, enquanto a DBM variou entre 2,8mg/mL a 11,3mg/mL. O aumento da concentração do óleo essencial no meio de cultura resultou no aumento da fase lag e diminuição da taxa de crescimento e DO máxima atingida pelas culturas. O OE em combinação entre os antibióticos apresentaram um efeito sinérgico na maioria das combinações, sendo indiferente somente frente à E.coli quando combinado o OE e ciprofloxacino. Os óleos testados não apresentaram citotoxicidade significativa nas concentrações de 50 e 100 ug/mL. / São Cristóvão, SE
146

Avaliação da ação cicatricial da seiva do Croton lechleri

Lopes, Thiago Vaz 21 August 2014 (has links)
Submitted by Ubirajara Cruz (ubirajara.cruz@gmail.com) on 2016-09-28T16:11:03Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_thiago_lopes.pdf: 1150861 bytes, checksum: 61c7489d8ca4f7e2d1391bb122629ae7 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-09-28T17:13:54Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_thiago_lopes.pdf: 1150861 bytes, checksum: 61c7489d8ca4f7e2d1391bb122629ae7 (MD5) / Made available in DSpace on 2016-09-28T17:13:54Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_thiago_lopes.pdf: 1150861 bytes, checksum: 61c7489d8ca4f7e2d1391bb122629ae7 (MD5) Previous issue date: 2014-08-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / O proposito deste estudo foi avaliar as propriedades curativas da seiva da espécie Croton lechleri. Uma extensa revisão da literatura foi realizada, e as propriedades tóxicas e medicinais conhecidas foram descritas. No entanto, apesar do grande uso pelas comunidades indígenas, não existe uma validação acadêmica dos efeitos dessa planta na cicatrização de feridas. Foram estudados 90 ratos da linhagem Wistar, com a realização de feridas cutâneas abertas no dorso, tratadas diariamente com Croton lechleri na concentração de 0,1 μg para o grupo I, grupo II com C. lechleri a 1 μg e o grupo III (Controle) com pomada não iônica, sendo realizadas avaliações clínicas, morfométricas, bioquímicas e histológicas aos quatro, sete, 14 e 21 dias de tratamento e estudo tensiométrico aos 21 dias. Na avaliação clínica das feridas aos 14 dias de tratamento, o grupo I apresentou maior presença de tecido de granulação, quando comparado ao controle (p<0,05). No estudo morfométrico, observou-se aos quatro dias de tratamento que o grupo II apresentou uma maior média de área (32,6 mm2) e a menor aos sete dias de tratamento (10,5 mm2) comparada aos demais grupos. Histologicamente o grupo II demostrou aos sete dias, um melhor resultado de suas amostras na fase proliferativa. No estudo tensiométrico, o grupo II apresentou a maior média (4,4065 MPa), não sendo observada diferença estatística com os demais (p>0,05). Os resultados levaram as seguintes conclusões: Com ação cicatrizante, C. lechleri a 1 μg acelera o processo cicatricial levando a diminuição da ferida aos sete dias de tratamento e leva a produção de um tecido capaz de suportar uma maior tensão, apresentando resultados satisfatórios como cicatrizante. / The purpose of this study was to assess the healing properties of Croton lechleri sap. An extensive review of current literature was performed, and the known toxic and medicinal properties were described. However, in spite of widespread use by indigenous communities, there is no academic assessment of the plant´s effect on wound healing. In this light, an experiment with 90 Wistar rats was conducted. Two wound were prepared in the back of each rat, and treated with C. lechleri sap at 0.001%, 0.0001%, and non-ionic cream (Groups I, II, and III respectively). The healing process was then assessed through clinical, morphometric, and histological evaluations of the wounds on days four, seven, 14, and 21, and a tensiometric assessment on the last day. Treatment with C. lechleri seems to have hastened the healing process by day 14, when group I had a greater amount of wounds with granulation tissue than group III (P<0.05). In the morphometric study, group II had larger wounds at day four (32.62 mm²), but presented faster healing and, by day 7, had the smallest area (10.5 mm²). Histologically, group II had a greater number of wounds in the proliferative phase by day 7 and in the tesiometric assay (day 21), this group had the greater rupture strength (4.41 MPa), however, this was not statistically different from other groups (P>0.05). These results considered, it seems clear that the C. lechleri sap at 0.001% hastens the healing process, rapidly reducing wound size within seven days of treatment, and producing a scar tissue capable of resisting greater pressure.
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Atividade anticâncer de extratos e frações obtidos de Croton campestris A.St.-Hil / Anticancer activity of extracts and fractions obtained from Croton campestris A.St.-Hil

Monteiro, Paula Araujo, 1985- 22 August 2018 (has links)
Orientadores: João Ernesto de Carvalho, Mary Ann Foglio / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T07:22:50Z (GMT). No. of bitstreams: 1 Monteiro_PaulaAraujo_M.pdf: 4137414 bytes, checksum: 6e1f10348a39fe1f0f4adcd72c6f7211 (MD5) Previous issue date: 2012 / Resumo: Fatores como o aumento na expectativa de vida, o tabagismo, alcoolismo e a má alimentação, vêm elevando a incidência de câncer já que o envelhecimento do organismo, assim como a ação de carcinógenos, favorece o seu aparecimento. Atualmente, essa doença é a segunda causa de morte na população mundial. As células tumorais caracterizam-se por ignorar os sinais externos e internos que regulam a proliferação celular, e tenderem a evitar os processos de apoptose e diferenciação, sendo consideradas muito invasivas. Grande parte dos quimioterápicos utilizados hoje no tratamento do câncer advém de pesquisas desenvolvidas a partir de fontes naturais como vegetais. Dentro do Projeto Fapesp-Bioprospecta (2004/07943-9) desenvolvido no CPQBA/UNICAMP, uma das espécies selecionadas, Croton campestris, mostrou interessante perfil antiproliferativo em cultura de células tumorais. No atual projeto, extratos, frações e princípios ativos obtidos de Croton campestris foram avaliados quanto a sua atividade anticâncer em cultura de células tumorais humanas e em modelo de tumor sólido de Ehrlich em pata de camundongo. Foram testadas diversas metodologias de extração a fim de verificar, com relação ao rendimento e à atividade, qual seria o extrato ideal para início do fracionamento. Dessa maneira, o melhor perfil de atividade no painel de linhagens tumorais utilizado foi observado para o extrato bruto por acetato de etila, tanto extraído a frio (CCEBAtot), quanto o a quente (CCEBAtotq). As frações obtidas foram submetidas ao teste antiproliferativo e as melhores amostras oriundas de cada extrato foram novamente fracionadas. As frações mais ativas foram CFb96-98 e CFqb14. Ambas foram submetidas à avaliação de parâmetros de morte celular como avaliação de apoptose e necrose e do ciclo celular sendo que os resultados observados confirmam a diminuição da viabilidade celular, aumento de população celular em sub-G1 e morte celular necrótica. A fração CFqb14, testada em modelo murino de tumor sólido de Ehrlich, apresentou resultados satisfatórios de inibição tumoral, bem como elevada potência visto que a dose mais baixa de 1mg/kg foi efetiva, comparada ao grupo controle. Testes fitoquímicos indicaram a presença de terpenóides nas frações ativas e através de espectrometria de massas, foi verificada a presença de duas substâncias já descritas na literatura, velamona e velamolona, que podem ser as responsáveis ou agir em sinergismo com outras moléculas, contribuindo para a atividade anticâncer. Portanto, esses resultados tornam a espécie brasileira Croton campestris uma importante candidata a fonte de novas moléculas a serem utilizadas no tratamento do câncer / Abstract: Factors such as the rise in life expectancy, smoking, alcoholism and bad diet are increasing the incidence of cancer because the aging body and the action of carcinogens favor its appearance. This disease is the second leading cause of death worldwide. Tumor cells are characterized by ignoring the external and internal signals that regulate cell proliferation, and tend to avoid the processes of apoptosis and differentiation, being considered too invasive. Most chemotherapy drugs used in cancer treatment today comes from researches developed from natural sources like plants. Results were obtained from Fapesp-Bioprospecta Project (2004/07943-9) developed at CPQBA/UNICAMP. The anticancer activity of extracts and active fractions obtained from Croton campestris were evaluated in cultured human tumor cells and in Ehrlich solid tumor model in mouse paw. Several extraction methods were tested to verify which one would be better for the beginning of the fractionation, considering efficiency and activity. The extracts with a better activity profile in the tumor strains panel used were obtained by extraction with ethyl acetate, both cold (CCEBAtot) and hot extraction (CCEBAtotq). Fractions obtained that presented the best results in the antiproliferative test were refractionated. The most active fractions of the respective fractionations were CFb96-98 and CFqb14. Both were submitted to the evaluation of cell death-related parameters and the results confirm a decrease in cell viability, increased cell population in sub-G1 and necrotic cell death. Fraction CFqb14 tested in Ehrlich solid tumor, a murine adenocarcinoma, showed satisfactory results of tumor inhibition, as well as high potency because the lowest dose of 1mg/kg was effective, compared to the control group. Phytochemical tests indicated the presence of terpenoids in the active fractions and through mass spectrometry, it was possible to detect the presence of two substances described in the literature, velamone and velamolone, which may be responsible or act in synergy with other molecules, contributing to the anticancer activity. Therefore, these results make the Brazilian species Croton campestris an important source of new molecules used in cancer treatment / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural
148

Ecological and Edaphic Correlations of Soil Invertebrate Community Structure in Dry Upland Forests of Eastern Africa

Mauritsson, Karl January 2018 (has links)
Natural forests are characterised by great vegetation diversity and create habitats for a major part of Earth’s terrestrial organisms. Plantation forests, which are mainly composed of a few genera of fast-growing trees, constitute an increasing fraction of global forests, but they only partly compensate for loss of area, habitat and ecological functions in natural forests. Plantation forests established near natural forests can be expected to serve as buffers, but they seem to be relatively poor in invertebrate species and it is not clear why. This bachelor’s degree project aimed at establishing the ecological and edaphic factors that correlate with soil invertebrate diversity in dry upland forests and surrounding plantation forests in eastern Africa. Some aspects of the above-ground vegetation heterogeneity were investigated since this was assumed to influence the heterogeneity of the soil environment, which is considered as critical for soil biodiversity. The obtained knowledge may be valuable in conservation activities in East African forests, which are threatened by destruction, fragmentation and exotic species. The study area was Karura Forest, a dry upland forest in Nairobi, Kenya. Three different sites were investigated; a natural forest site characterized by the indigenous tree species Brachylaena huillensis and Croton megalocarpus, and two different plantation forest sites, characterized by the exotic species Cupressus lusitanica and Eucalyptus paniculata, respectively. For each forest type, six plots were visited. Soil invertebrates were extracted from collected soil and litter samples by sieving and Berlese-Tullgren funnels. The invertebrates were identified, and the taxonomic diversity calculated at the order level. The ecological and edaphic factors, measured or calculated for each plot, were tree species diversity, ratio of exotic tree species, vertical structure of trees, vegetation cover, vegetation density, litter quality, soil pH, soil temperature and soil moisture. One-way ANOVA was used to compare soil invertebrate diversity and other variables between different forest types. Akaike’s Information Criterion and Multiple Linear Regression were used to establish linear models with variables that could explain measured variations of the diversity. There was some evidence for higher soil invertebrate diversity in natural forests than in surrounding plantation forests. The abundance of soil invertebrates was also clearly higher in natural forests, which indicates that natural forests are more important than plantation forests for conservation of soil invertebrate populations. Soil invertebrate diversity (in terms of number of orders present) was found to be influenced by forest type and litter quality. The diversity was higher at places with high amounts of coarse litter, which here is considered as more heterogenous than fine litter. The dependence on forest type was partly a consequence of differences in soil pH since Eucalyptus trees lower soil pH and thereby also soil biodiversity. No relation to heterogeneity of above-ground vegetation was found. For future conservation activities in Karura Forest Reserve it is recommended to continue removing exotic plant species and replanting indigenous trees, to prioritize the removal of Eucalyptus trees before Cypress trees, to only remove a few trees at a time and to establish ground vegetation when doing so.
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Isolation and characterization of antifungal compounds from Clerodendron glabrum var glabrum (Verbenaceae) used traditionally to treat candidiasis in Venda, South Africa

Masevhe, Ndivhaleni Anox January 2013 (has links)
The aim of this study was to isolate and characterize antifungal compounds from the most active medicinal plant species that could be used to address secondary infection problems in immunocompromised patients. An ethnobotanical study was conducted and 45 medicinal plant species used traditionally to treat candidiasis and related infections in HIV/AIDS patients were identified and documented. The most popular plant species used included Acacia caffra, Clerodendrum glabrum, Croton gratissimus, Elaeodendron transvaalense, Faurea saligna, Hippocratea longipetiolata, Osyris lanceolata, Richardia brasiliensis, Schkuhria pinnata, Schotia brachypetala, Spilanthes acmella, Strychnos potatorum, Vangueria infausta subsp. infausta and Withania somnifera. The plant parts used in the therapeutic preparations were roots (26.7%), bark (22.2%), and a combination of roots and bark (17.7%). Decoctions (44.4%), infusions (20%) and macerations (17.7%) were used. Most of the herbal remedies were administered orally. Chemical profiles of the plant species were established by using thin layer chromatography. Leaf extracts of these plant species were tested for antimicrobial activity against two common pathogenic fungal species in humans (Candida albicans and Cryptococcus neoformans) and four nosocomial bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa) using a two-fold serial microdilution method and bioautography. All plant species investigated had some degree of antimicrobial activity against the test microorganisms. The hexane and the acetone extracts of Clerodendrum glabrum, Hippocratea longipetiolata, Schkuhria pinnata and Withania somnifera were the most active with MIC values ranging from 0.06 to 0.08 mg/ml. The most susceptible pathogen to the test samples was C. neoformans while C. albicans was resistant to most of the plant extracts. The water extracts of Withania somnifera and Hippocratea longipetiolata (14%) had MIC < 1 mg/ml against C. albicans. C. neoformans was susceptible to nine water plant extracts (64%) with MIC < 1 mg/ml and the promising activity was observed in Hippocratea longipetiolata and Faurea saligna extracts with MIC values of 0.16 and 0.31 mg/ml respectively. The hexane extract of C. glabrum was the most active against C. albicans with an MIC value of 0.06 mg/ml and total activity of 550 ml/g. In the bioautography, most plant extracts tested had few active compounds, others had no active components at all and this may be attributed to the disruption of synergism by the thin layer chromatography. C. glabrum had eight active antifungal compounds on bioautograms and most of these components were observed in the EMW solvent system. Based on this and its wide distribution in rural areas, C. glabrum was chosen for further study. The antioxidant activity and possible immune boosting potential of the species were determined using 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH), 2, 2’ azinobis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assays. In the DPPH qualitative assay, the aqueous plant extracts had several prominent antioxidant components than the organic plant extracts. The aqueous plant extracts which had the most prominent antioxidant activity were F. saligna with 8 compounds, followed by E. transvaalense, H. longipetiolata O. lanceolata, R. brasiliensis and S.brachypetala, with five compounds each and their Rf values ranged from 0;06 to 0.94. This appears to validate the ethnomedicinal use of the plant species to some extent because decoction is the most common method used in the preparation of the remedy by the traditional healers. With regard to the organic plant extracts, only one plant extract, F. saligna had two prominent antioxidant components at Rf values 0.81 and 0.88. A third of the plant species had a high level of free radical scavenging activities in the DPPH, ABTS and FRAP assays. However, all plant extracts had lower antioxidant activity than the positive control (Trolox) used. The selected plant species were also evaluated for their in vitro toxicity against the Vero monkey kidney cell line using 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. The acetone plant extracts of O. lanceolata, S. acmella, S. pinnata and S. brachypetala had high cytotoxic activity against Vero cells with IC50 values of 13.7±0, 19.9±0.001, 21.6±0.001 and 28.34±0.001 μg/ml respectively. However, their IC50 values were higher than that of the positive control, doxorubicin (IC50 = 9.9±0 μg/ml). The rest of the acetone plant extracts (64%) had moderate cytotoxic activity (30 < IC50<100 μg/ml). The aqueous plant extracts were relatively non-toxic to the Vero cells with IC50 values ranging from 137 to > 500 µg/ml. This supports the use of aqueous extracts in the traditional medicine. However, their low selectivity index values ranging from 0.26 to 1.68 suggest that the plant extracts are probably suitable for external use only. Fractionation of the hexane extract of the leaves of C. glabrum by chromatographic techniques yielded six fractions of which fractions C and D had significant antifungal activity (average MIC value = 0.1 mg/ml) against C. albicans and C. neoformans. From these fractions, one new triterpenoid, 3-(1-oxobutyl)-11α-hydroxytaraxast-20(30)-ene-24,28-dioic acid (clerodendrumic acid) (1) was isolated along with known heptadecanoic acid (2). C. albicans was relatively insensitive to clerodendrumic acid (1) (MIC value = 125 µg/mL) and was resistant to heptadecanoic acid (2) (MIC value = 188 µg/ml). Compounds 1 and 2 were non-toxic against monkey kidney Vero cells in vitro with IC50 values of 202.6 and 108.4 µg/ml respectively. Due to its low antifungal activity, the novel compound clerodendrumic acid (1) is not a viable candidate for drug development which could be used to combat candidiasis and related fungal infections. However, due to its relative safety, it may possibly be used as a lead compound to produce new chemically modified active derivatives or could be used together with known antibiotics to mitigate their undesirable side effects. To the best of our knowledge, the isolation of a novel, clerodendrumic acid (1) and a known heptadecanoic acid (2) compounds from leaf extracts of C. glabrum is reported herein for the first time. The results obtained from this study generally substantiate the rationale behind the use of the selected plant species in the traditional medicine to treat candidiasis and related infections to some extent. This study showed the potential of studying traditional medicine in the search for effective plant extracts or new lead compounds that could be developed into drugs for combating microbial infections among the rural poor people. / Thesis (PhD)--University of Pretoria, 2013. / gm2013 / Paraclinical Sciences / Unrestricted

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